-:< 

# NOx BEST AVAILABLE CONTROL TECHNOLOGY ANALYSIS STUDY
fo' 

# Milton R. 

# Young Station Unit 1 Minnkota Power Cooperative, Inc.

Revised Final Report October 2006 

## 31777 

# Minnkota Power IMPel COOPERATIVE, INC. YoutTouchstone Enetgy® Partner

# ~)\ 

# -

# NOx Best Available Control Technology Analysis Study for Milton 

# R. Young Station Unit 1
prepared for


# Minnkota Power Cooperative, Inc.

October 2006 

## Project No. 31777 Revised Final Report prepared 

## by Burns & McDonnell Engineering Company, Inc. Kansas 

## City, Missouri

COPYRJGHT 2006**,'~** BURNS & McDONNELL ENGINEERING COMPANY, INC. 

# :,

-- -\

# INO, HACfAnaly>i., Sludy



### TABLE OF CONTENTS TobIe ofO:mlrnlJ;



### 1.0


### 2.0 

# " 

# " F.XJ<XUTlVr. SUMMARV.............................•••..............•...•.•..••.....•....ES-I

INTRODUCTION 1

"TOP-DOWN" NOx BACT ANAL)'51S APPROACH 2_1 STEP I -IDENTIFY ALL CONTROL TECHNOLOGlTIS

__ .. . _ 2_1 STEP 2 - ELTMrNATE TEClfNICAU.Y fNfEASIBLE OPTIONS

_ . 2·] STEP J _RANK RFMAINING CONTROLTECHNOLOGlES BY CONTROLEFFECTIVENESS 2·4 STEP

. EVALUATE THE MOST EFFEcnVE CONTROLS AND DOCUMENT RESULTS_ 2_5 S'IEP 5 _ SELECr BACr

. _ 2-6

-

# -, 3.0 BACT ANALYSIS for MRY STATION UNIT 1 NOx EMISSIONS 3-l 3_0_1 EMISSJON UNIT DESCRIPTION ._._._........... . _3.1 30.1 NITROGEN OXTDES EMISSION FORMATION

_ >0 0>

_ _ __3·3 3_1 IDENTIFICATION OF No-, CONTROL OPTIONS FORMILTONR. YOUNG STATION 3-3 J_ I. I REVIEW OF RETROFIT INSIALLATIONS ._ 3-4 _;.1.2 PUrI,NTIALLY FEASIBLE**~O,** CUN mOL UPTiONS FOR MIl.TON R_ YOUNG STATION J-5 J.2 FEASIBILITY ANALYSIS

.. _.]_6 .J 2_1 SUMMARY 01' RETROFIT INSTALLATIONS OF NO, CONTROLTECHNOLOGIES

.._ ..3_8 3.2_2 SUMMARY OF FEASIBLE NO, CONTROL TECHNOLOGIES FOR MRY STATION _.3-9 3.3 RANK OF TECHNICAU.Y FEASIBI.E NO, CONTROL OPTIONS DY EFFECITVENESS J-13 3.3.1 ESTABLISlIlNG DASELINE NO, EMISSIUNS FOR RANKfNG CONTROl. OPTIONS

..._._ _ 3-14 3.3.2 ESTIMATING CONTROL-EFI'ECTIVENESS OF NOx CONTROLOPTIONS

.... '-**~_15** 3.4 NO, CONTROLS EVALUATION AND IMPACfS ANALYSIS.. .3·20 3.4.1 NO, CONTROL ECONOMIC IMPACTS FORMRY STATION UNIT I .3·20 3_4_1_1 CAPITAL COST ESTIMATES FOR NO, CONTROL ALTERNATIVES 3.20 3_4_1_2 OPERATING AND MAINTENANCE COSTESTIMATES FOR MRY STATIONNOx CONTROLS 3-22 :1.4_1.3 I.EVELIZD TOTAL A}''NUAI. COST ESTIMAms FOR MRY STATlONNO, CONTROLS__ 3·24 3A.2 ENERGY IMPACTS 01' MRY STATION NO, CONTROLS

.. ..__ '- 3·31 3.4_2.1 ENERGY IMI-'ACI'S 01' SOfA UCHNOLOGY..... _)

..31 JA.12 ENERGY IMPACI'S OF SNCRTECIINOLOGY

.._ _ ._.. ..**_~·)2** J_Ll EKVIRONMENTAL IMPACI'S OF t--IO, (:ONTROl.S -MRY STATION_ :**3·~5** ].4.3 I ENVIRONMENTAl.I),IJPACTS OF SOFA TECHNOLOGY

__..**J·~5** 3.4.]_2 IoNVIRONMENTAI. IMPACTS OF SNell. TECHNOLOGY

_ _................... 3·36 

## tuJ;nnk"l"

## P""~r-(-·""-,-,,-,,-""-,-.ll~,::- --- ------

## --,,"o"c~~.,-----------n~"==.&'M=cDonndlNO, BACT An.lysis Sludy Table ofConltnts

----- --**-~----** 3.4.4 SUMMARY UF ECONOMIC, ENERGY AND ENVIRONMENTALIMPACTS OFMRY STATION NO,CONTRULS ,......... . _ " 3-37 3.5 BAC]" RECOMMENDATION AND CONTROL U,VELS

_ MRY STATION UNIT I _

.._._._ _, ,3-39 3.5_1 3.'i.2 UNIT I NO, BACt".. EMISSION RATE LIMITATION RECOMMENlJATION

.. .. ...3-40

APPENDIX A , 

### Technical Feasibility Assessment Details for NOx Conlrols (A1) U.S_ Coal Cyclone NO, Reduclion Pmjects Summary and Retrofit NO, Conlml Projects' Technical Lilerature Summary (A2) 

### APPENDIX 

### B EERC Report
- Ash Impacts on SCR Cillalysl Performance (B)


### APPENDIX C 

### Cosl Melhodology (C1) CapTlal Cost Eslimate Delails for NOx 

### Controls (C2) O&M 

### Cost Eslimate Delails for NOx 

### Conlrols (C3)

[JU'"S & McDollnell 'lUC-2 Minnkota Powe,Cooperotivc, 

### Inc.NOx [IACTAn,lyslS Sntdy


### LIST OF TABLES T.ble ofConlonl'

Table J-l

- Unil J)e,ib'll Pammcle,:; Table J-2

-- IhSlorieal Average Ligmte Co"1 Analysis Tublc 3-3

__ POlc'Tlli:olly IIv,"luhle NO, Conlrol Technologies Idenlified for BACT**A~alysis** Table 

### 3-4

- Idemifled 

### NOx Conlrol SySlcm Retrofils on Cyclone Coal-fired !loiler, TalJ1e 3-5 - TcdLllic;llly I'eosiblc Potcnlial 

### NOx Control Technologies for 

### M.R. Young SllItion Cyclone lloiters Table 3-6

- TecImically Infeasiblc**l'ot,-,~li,,1** NO

### x Control Technologics for M_R_ Young Station Cyclone Boiler, Table 3-7

- R,mhd No,. Control 0l'lion. Fea.ible for MRY Station Unit] Boilcrwilh Expected Conlrol PerfOmltinee T"blc 3-8

- Expeolcd Anmml 

### NOx ConlTol Performanoe [orMRY Stalion Unit I Allernatives Table 3-9 -Unit Capilal Cosl Faclors o[f'e:o,ible

### NOx Conlrol Option for MRY Slation Unit 1 TallIe 3-10

- ESlimulcu Capilal Co.ls for 

### NOx Conlrol Alternalives 

### -MRY Slalion Unill Tablc 3-11

_ Estim"lcu 

### OMI CoS< for 

### NO, Control Allernatives

- MRY Station Unil I Table 3-12

- Eslimaled Annual Em15,iuns ,md Lcvelize{] Total Annual Cost forNOxConlrol Allcm"ti"",s MRY Slation !J1ll11 Table 3-13

- Dom,nnni Conlrols CO'l Cun'e Poinls for Feasible BACfNO

### x Ahematives

- MRY Swiion Unil I Table 3-14

-**~~<tll1wted** Emissions 

### "ml Economic**Impa~lS** Summary for NO

### x Control Alternative.- 

### MRY Sl:otion Unil I Table 3-15

--**1i"p<:~lc,1 Au"ili~ry** **Iilemi~a]** Power Impacts for NOx Conlrols

- MRY Station Unil I T"bk 3" 16**cxpc~led** Eleelrical Powcr Gencmtion Availability and Capacity Impacts for 

### NOx Controls

- MRY .slation Unil 1 Table 3-17 -Expeoled Tolal Eleclrical Power Gencnltion Impacls for NO

### x Conlrols

- MRY Slalion Unit 

# , Table 3-18

- Summ.ry ofTop-Oown BACT Impact Analy.is ResuH, for Dominanl NO

### x ConlrOl Altemalives

- MRY Slalion Umt 1 Table J-19

- NO

### x Emis.ion Conlrol Technology and R.11e Recommended 3' BACT forMilton R. Young**S~,lion** Unil 1 Tablc 3-20 -Iteeommended**NO~** BACT Conlrol**M~thod** and 30-Day Rolling AverageNOx Emission 

### R"IC Limit Wilhol1t SIUr1\lpS Table 3-21

- Recommended NO, BACT Conlrol Method and 30"Day Rolling AverageNOx Emission R;'lc Limit Wilhoul**Sl'rlup~** Table ]-22

- Recommended 24-llollr Rolling; AvemgeNOx Emission IUlte LimilDuring Slartup'

MinnknLo Po\\"a ("onl'er:HJ"e. Ino.

### NOx AACT Analysis Srudy

_._

## .. LIST OF FIGURES Table**ofCon\~nl>** 

# _._--

Fl£ure 3-1

- NOx Control CO"! Effcc!iveness

- MRY Station Unit 

### J Figurc 3-2
- MRY S1alion Unil 1 NO

### x Control Altcmatives Domioant Controls Cosl Curve 

### Appendix A1 [,igure AI-I
- 

### Pul"eri7<o(1 Coal Reburn Applioalion on Cyclone Doiler With Ovcrli", Air Figure AI-2

- 

### Natural Gas Rebum Applicalion On Wall-Fireu Pulverized Coal Aoilel' wilh Ovcrfire Air Figure A. 1-3

- l-Iydrocarbnn-.enhanced**~NCR** 

### Application on PC-fired Boiler f'lgWrc 

### A. 

### I-4

- Rioh Reagent Injection App] icalJon on BoilerWith Overlire Air F,gure A 1-5

- Convenlional lligh-Dusl Sc."RArrungcIncnl wilh FGD Scrubbcr Oullet Reheal Figure A.I-6- 

### T,iP,a, SCR Ammgemenl**f'igur~** A.I-7

- 

### Elcclro_Cntalylic Oxidation (ECO") Process ['low Diagram

Dum, & McDOIHldl 

### TOC-4 MHl,1kola Power ('",opcmIive. T no.

### EXECUTIVE SUMMARY

Thc Millon R. Young Slalion ofMinnkn!ll PowerCnnperntive, Inc_ (Minnknla) and Square Bulle Electric Conperalive (Square Bulle) indullcs lwo cyclone-furnace, lignile-fired sleam-clcctric generaling unils (SEGUs). The unils bOlh fiie Nnrth Daknla lignile supplied from the adjacenl mine, ncar Cenler, North D"kol,. Unit 1 has a nominal 235 MW nCl design outpul**C~p"Cily** roling, is typically capable nfsustained nUlpul**ofoppro~im",cly** 250 MW, (gmss), and has a gmss design nUlput capacityroting of257 MW,. Unil 1 is owncd and opcrotcd cntirely by Minnko.La_ Unil2 has a nominal 439 MW netdesign nUlput capacity mLing, is capable ofsuslaincd OUtpUI ofapproximatcly 

### 460 MIN, (b'TOSS), and has a gross dcsign oulpul capacity raling of477 MWg' Unil 2 is oWIled by Square Bulle .Electric Coopcrmivc (Square Bullc), and Oper1l1ed by MinnkoLa.



### A Nolice ofViolalion (NOV) from Ihc Unilcd Slales Environmenlal Prolcclion Agency (US EPA Or EPA) was issued 

### La Minnkola Power Cooperalive on June 21,2002. 11,c NOV alleged thaI modifications had been made allhe Milton R. Young Station lhat would have required a construclion permil under New Source Review (Code ofFcdcml Regulalions 40 CrR 52.21, 

### fill! NorthDakoln AdminiSlrative Code NDAC 33-15). As a resull ofthis allegalion, a civil complaint was filed by the Unile<! Slales ofAmerica and the Slale ofNorlh Dakota againslMinnkota Power Cooperative Inc. ("Minnkol''') and Square Bulle Elcclrie CoopcTdlivc ("'Square BUlte") in the Uniled Slales Districl Court forthe Districl ofNorth Dakota_ A Consent Decree (CD) has been apprnvcd lhut rcprcsc'111s final**ne~olialed** SClllcmenl ofthe Uniled Slales' and North Dakola's claims againsl Minnkotu anll Square Hulle. The ConsC"Ilt Decree requires Minnkola and Square Butte 10 perform a "NOx Top-DoWIl Best Available Control Technology (BACT) Analysis" to describe lhe CIlllssion limil_ for NOx that will be requued al Units 1 and 2, c;\pressed as a 30-D;IYRolling Avcrage NO

### x Emission Rale [Consent Decreeparagraph 24, page 7. and paragraph 5,**p,,~e** 

### 4]_

Bums & McDonncll was**n;l~incd** lO conduct a Top-Down BACT Analysis for nitrogen oxides (NOx) 01 lhc Millon 

### It. Young Stalion_ Thc results ofthe BACT analysis arc prcsmtcd in lhis sludy report.

The procedures mandated by lhe Conscnl Decrcc forpcTforming a Top-DoWIl BAC[ Analysis are oUllined in Chapler B oflhe 

### U_S. EPA's**Ne'X.$~o_lJ~~_{~eview** Workshop Manual: Prevention of**Sigl)ific~-'lLDeterioratlon**an>! N9nallainmcnt 

### Are" Permilting, I)rafl Oclobco 1990 ("EPA's NSR Manual"). The MRY Sl;llion BACT analysis was perlonned in acconiance wilh lhi, procedurc. The

MiLlnkOla PowerCoopcmlive, Inc. ES-l Bum.> & MeDon"dlExecutive Sununory NOx BACT Analysis Study


### Ej'A 's 

### NSR Mumml oullines nve basic slGps tbal 3rC 

### 10 bc followL-<l 

### in lhls BACT analysis. Thesc basil' ,tep' (or 'UGh a RAer analysi, an:: ,umrnori7ed a, follows:
Slep I -IJenlily An COLltrol TeGhnologies Slep 2 - Eliminate Tedmictilly In[c"siblo Options Slep ] -lbnk Remainmg Cona'ol Technologics by Control Effecl, veneS.I Slt.l' 4

- Evaluale Mosl ElIc"Llive ContIoh and Document It

..,ults Slep 

### 5 - Select BACT

A nest Available Control Tcchnology (BACT) an"ly,is was per[mmed for Millon R. Young Unit 2 for NO

### xusing the EPA's "lop-down" "ppronch. De.,t Availahle Control**Techuolo~'Y** i, ,ldined 

### as "an emiosionllimilation (including a v"iblc erni,slon <Iandord) ha""d 011 the m""imum**de~'rc""** orI'edUClioll for c""ch polJul,ml SUbJecllo regulation under Act wh"h would 

### be cmitlerl rrom any propo"'d rn"Jor stalionary source orm"jor mOlEfienlion which lhe IIdministrJlor, on a G"sc-by·cuoe ha,is, taking inlo ncooonl onergy, environmenlal, and cconom;c i"'racL, and Olher CO.'I", delermines is achievable Lor ,uch

sourcc or rnoJifio" lio" Ihmugh applioalion ofproduotion prooesses or 'l\{uilabl" ",elhod." sy,tem" 

### "ml lechmques, including 

### fuel ele,minft Of tl'eatment or innovative ruel comb"slion lcelmi'lu'" tor conITol of .,,,oll po]]uLanl" (40 CFR 52.21, NSR ]vhTTlual 

### R Il.

Unit I "I Milton 

### R. Yllung SlatioLl is 

### a cyclone-fired boile, Ih"l bums North TJnkllLa lignite. The meLhOO offiring is very**si~'lIifieuIl(** TTl aTlolyzJIlg control oplions [or NOx emissions. 11 cycloneboiler produces inherently higher uncontrolku NO,**le~e1s** lhan pulverized-coal and cireulaling fluiuizeJ bed boilers. There have been no ncw ccml-buming cyelo"e-lired hoiler,; huilt and inslalled in thc Uniled SLale.' ,;ince Ihe**e~r]y** 1980's. Consequenlly, Iherc nrc no clillmplcs ofBACT cunlrol opllons 1isled in lhe RACl'lBACTfLAER Clcanllghou,e dambase for coosiueration and direct "ppliculioTl orpublisbeu NOx cmission permit**limil~** On Ihc Millon R. Young eyc1one-fireu hoilers.
Slep 

### I -lllcnii

### fy A

### 11 Conlml**Techno.loKi,~1i** The Consenl D.-cfCe requirc, Ihatthe NOx Top-Down HACT Anal)',," for the MillOn 

### R Young Sialion "mchlllc un eva]ualior\

# orSeleotn;e Catalytic Rcduction (SCR), Selc"tivc Non·Calalytic Rcuuclion (SNCRj, Overfire Air (OFII), Rich Re"gcnllnjeclion (RRI), a, well a< olher NOx conlru]tochl\ologlCs" potenlially applioahle for lignile--fireJ cyclone boilen; [O)nS'"Tl1 Decree paragraph (,5, page 19]. Olh"[ identilied contmllechniques, such as [uel swilding and Iud clenTlllIg, and combuslion-relaled "rni&sion eunlrol Icohnologic"**~uch** ", f'le! I'ehnm "nd oxygm-c"Tlhanced combuslioTl, wer"**"l~o** coll"idered.
Dums & McDonnell ES-2 Minnkolo Power COop"'"I"'", IncNOx BACTAnolysis Study Ex.o<:utivo Smrun



# l 

# , Step 

### 2

-**Elimin~te** Technically Infeasible Options 1be BAC!' evalualion dcMminc"" that nOI all the technologies idenlified were consid"",d av"ilable ond applicable. The teohnically infeaslble altemativcs wcre e1imin.tc"" from fUTtller evaluation, along: wilh feasible tedmologios with economic impaoL< thot were unrcasonable compared to olhercost·dliei"I!t alternalives to control NO

### x emissions for 

### MRV Station Unit 

### 1.

The tcohnic"1 fca,ibility ofapplying: NOx emission reduction kehniques and leclmologics atMilton R.


## , Young: Stalion is dominatcd by the comp,,-,ition and combustion**~haraelerislics** ofthe North Dakota lignite supplied solely from a**surfac~** mine adjacent to the plant. This minc is the only supplier ofsolid fuel for ,his slauon, "" there are no railroad faeililies pmvided to service the Millon 

### R. Young plant. Nonh DakoLa lignite has high moisture and high sodium content., moderate**high~'r** healing values. and can have a widely variablc and high ash conteat compared to other coal,. TheSt' characteristics Crc;Jle dirliculties in promoting co",istent, sleady eomblL,tion and slag fonnation in 

### the cyclone burners. It also**r~sullS** in producing a 11yash lhat has severe deposition characteristics.

Both boilers include a unique coal comJilioning system (drying, crushing, and feeding) for each cyclone furnaoe specifically designed to aid in proper combuslion of!he Egnite Cuel. "Ibis method offiring solid fuel si;:uificanlly influences the resulting nitrogen oxide eoncentration ofthe flue g;IScs emitted from the boilelS.

Ash dep,,-,ition in eachboiler and air prchc""",r is a significanl operational clmllengc ror the facility. SIgnificant equipment and manpowerresourecS are devoled to on·going ,emoval offireside a,h accumuJ;,tions_ Unit outages musl be conducted at regular inlCrvals (0 clean each boilcr(appToxillllltely every 

### 80-120 days).**Th~-rc** are " numher ofi<sues that make seleetivc catalylic**reduc~on** 

### (SCR) technically infeasible for NO

### x emission conlrol for Milton 

### R. Young Unit 

### 1. The con.<;stent long-term operotion of

### SCR technology on lignile-fired cyelone boilers 

### will he draslically inhibited by lhe susceptibility ofthc 

### SCR catalyst 10 severe fouling, deactivation, and crosion resulling from the aelions of the emitted llue gases and llyash, and ash deposit removal operations_ 

### SCR tl"Chnology is cornidcn"" technically infc",iblc for applicalion on the cyclone boiler1> HI thc Milton R. Young Station.

Rich Reagent Injection h"s been demonstrated on boil= buming bituminous and suhbituminous coal. Howcvor, it has nOI 

### bttn commercIally installed and placed in continuo", operation On a cyclone-Iired boiler burning lignite coal with high foul ing and slag IcmperJture sC"Ilsitivilics associated and a highly

Minnlwla Power CO"P"mlive. Inc. ES-J D"ms & McDonTIcllh,-,,"llVC SUITIffill'Y NOx BAlT ADaly,i, Sludy

variable neat comenL RRI adds ure" rc"1,,,-.,,llo Ihe hot J\Jmncc gUSe" nc,n Ihc cyclooes, which must be devoid o[frec oXY,:cn in order 10 avoid oxidation ofthe urea, and Ihus erealing; NOx. While RRI is speciflcally inlcmTcd for NOxemissions cOl\trol on cyclone boilers, RRI is considered lechnically infeaSJhle Jor applicalion on Ihe ILgnile fired eyclune bOlkrs allhe Millon R. Young Slalion due 10 the vurwbTc heal eontenl o[ Ihe hgnile [uel which allow, the creation ofoxygen-rich conJilions lD lhc boiler.

The uppll",,110n of'epamleu Ove, IiIe air (SOl'A) [or NUx emISsions control on Millon R. Young Unil I**'~** boiler wns evaluated as p"rt ofIhe BACT imalysis. Ave, sion of.,epamled overlire air speeific"lly designed [or increased NO, emission rcduelion pcrfomLa1\cc fOT lignilc_Grcd cyclone hOllets, referred 10
as "Advanced SOFA" in lhi.' analysis, can be ",slallcd on bolh unils nl M,R, Yo,mg Slnlion_ Tlli.' highc,l-pc,forming form o[ SOl'A call he applied alo1\e and 1Il combination with olhc, tcchnoloeie&. Key '''pecls o[ ,ucccss[ully applying "ml operating a separaled ovcrfire air sySIem on a cyclonc-fire,1 bOller "re Ihe ab;liry to:

• AccufaIely**measur~** the fuel heal ;npul rale (BTUs) ,mu cumbu,lion air inpulo Oil n real.l;me, inul\'idu,,1 cyclone by cyclone baSl&, 10 allow Ihe ahility 10 delenmne and control the desired ,,;rfIud ralio, especially when '",lnrvcd air' (i,e. s\lb,IOlehll)ll'Clric) eomb"sllon e01ld11101\" are I'eqlllred.

• Moinlnin at!to(lunlC mullen coal ash (,lag) fomlalion "",I now wllhin the b"rrcl, ,md**~l"g** lap.,_

The degree I" which Ihe indivIdual cyclonc [urnace, e'lll he opemled w;lh lcSS_lhan_theorelical (suh.,mic11iomell'ic) cOmbu.'lion air, whIch corresponus lu opm,llon u[ a SOl-A oy,lem, direclly c01\!ribulcs 10 lcs, combuslion-rc1aIed NO

### x formati"n and**furlh~r lI1-furnac~**  emiBslOn redueliun but nJoo nob ,0Ii,lifie;]lion o[Ihe mollc"Tl e0;11 ash. This pInee, great emphasi, on achie"ing t,ghl control over Ihc un/fud mlios on each cyclone during "ir-Slaged COmhu,lion IIp,,,alioll wilh SO!'A in order for "ir-,Iaged eombu,tioll to be .,ucce.,sful in producing signiflcanl ,,<1,liliomll NOx**c"Tl1i~sions** reduclioH On lignile-fired cycloLle hoilers.



### In Ihc c"se ofMRY Stalion Unil 1', boikr, "ir-sl"ged cOmbuslion mu,l**b~** ,ufficicm In reduce NO, emissions while relea,ing enough heal 10 continue 10 rnel1lhe [lid "sh so Ih"l il fJuws dicclively wirhm and lrom Ihc cyclone burners. Due 10 the "hmt-lelln variability ofthe combustible anu "sh eomponenLo of Norlh Dakota hgnite ,upplied from Ihe current mine ncar CC"Tltcr, NIl, and Ihc eump1cx belm"i"fofIigLl;le nsh when cxpo",d 10 high lemperJtmcs. Ihe exlcol ofair-slaging "nd IhtlS the level ,,]'NO, control while operalmg the highe"I-l'erlormlng ver.<ion o[SOFA syslem IS cxpeelc-u 10 be mode'l.

Durn> & McDonnell Minnkola Power Cnnperollvc, IDe_

### NO" BACT Analysis SlUdy aoon



### Seleclive Non-Catalytic Rce.luclion (SNCR) lechnology has been used 10 reduoe NO" emissions,
numerous ulility boilers burning: enslern biluminous coal, midweslern bituminous coal, ancl, to a 1< ""lenl, western subhituminous coal. SNCR has aloo been used On fuel oil and natural gas-fired unil SNCR docs not apPC-dr to be**cl~l'endenl** 

### directly On 'he tyPe ofburncrs (wall-fired, langentially_fin.-d. eyclone-Iired) employed in the boilers**wh~'TC** 

### il has been**ins~llled,** 

### with or wi1hout air_staged combust with ovemre air in full operatinn_

There arc siboniIieant cOncerns associnled with elTective long_term SOFA opeHlion forMillon R. Young Sinlion Unill 's boiler. The ability ofbasic combuslion equipment and improvements to precisely
measure lhe boiler's heal input rale in real-time on an individual cyclone by cyclone ba,is wi!b compensation lor lhe short_term variability ofthe combuslible content ofthe Center lignite 10 consislenHy muintnin Subsloiehiomelric opcmtion ofevery cyclone during air-Sl:lllCd combuslion is unproVCll_

Several olher lechniques and technologies were considered lechnically feasible for NO" emissions control at MRY SLation: fuel BlClldingiSwilChing; Basic Combustion Conlrollmpro"emenLs; andvarion.< forms o[Fuei R"bum. Fuel swilehinglblencling was uOI evaluated [urlher because o[expecled uillCasonably high capital and operating cosLs and no**addi~onalemission** 

### reduclion compared 10 continued lignite firing_

Othe'r NO" cmi'5ions oontrollechniquc>; "mllCohnologies JOr 

### MRY Slalion that**W~'re** 

### evaluated and dclermined to be lechnically infeasible wcre: Fuel Cleaning; Low NOx Burners (LNE); Flue Gas Recirculalion; Oxygen-enhanced ComhllSlion (OEC); Waler/sleam injeclion**(combus~on** 

### lempering); and Electro_Catalytic Oxidation**(ECO~.** 

### Step 3 Rank Remaining Control**T",lmolo~ie~** 

### by Control EITcclivmess "lbe lhird slep in !be ·'Iop-down" BACT evaluation ITlnked lhe remaining control leclmoJogies by eITecllvene:ss. Thc purposc ofranking lhc oontrol technologies was 10 eSlrlblish a hierarchy thai places at lhe "lop" lhe control teclmology lhat achievc" the lowcsl emission level. The leclmologics in order of lheir effectiveness, from highest 10 lowest, are, SNCR wilh ASOr-A; Gas Reburn wilh ASOFA; Lignile Reburn with ASOFA; Fuel Lean Gas Reburn with ASOFA; ,md Advanced Sepa11l1ed OverfIrc Air (ASOl'A). None o[lhcsc control**option~** 

### has been inslalled on a cyclonc-Iircd boilcrburning North Oakola lignile_ A< .<nch, !hc expressed control rel'cenlages reflect the me of**engineeringjudgm~"11I,** 

### bused all lhe listed teclmique ortechnolob'Y applic"lion. 

## <--
-

Minnkola PowcrCeoperative, Inc_**E~-5** 

### BmIL< & 

### McDonnell**E",,~uliy~** SmruIl"y

------_._- NOx f1ACl' AIIaly,j, SlIlJy

Slep 4 Evaluale Mru;t Effeclive Conlrol, and**DocL!rn.en!Resllh~** Addiltunal crilo,ia be,ides lechnic"l [c"sibililY were ulili7.ed for lcchnology selection in Ihis 

### BACT analysis. The"" included cslim"les 

### ofcontrol effeeli,'cnc" (i.e. percent pollul"nl removed), capilalplus upcmlmg "ml maiTLlen"nee costs, mmllalemi"t{)<\ I educlion (Ium; poryenr), e"orgy imp"els, "vc,"ge "nd incremenlal eosl effeClivene", ($/lon), "nd environme"llial i"'paCls (olher mcdi" and cmi<sions ofloxic "",1 h"z"rdous nil' pollutant,").

The economic an"ly", exammed lhe c"pilal cosl ufench feaSIble HACr allemativc cvnluated and any olher powerplanl upgr;tuc cusls neee."ary 10 llnpkmCJIt**lh~** allCrnallve. In addition, Ihc economic mmly:;i:; eX311ltncd Ihe operalill!,: amI rnamLellance cost ","OGi"lerl ""tlh the highcst-perfomling form, 0L e,ch fe",ibk RACT .llema(ive ev"llw(c,1. The,", cosL, were Ihcn**eumbin~d** mlO a levelized lul,,1 "nn""l cost for" comparalive asscssmenr ofIhe lol"l irnpJ,:mOnl:llion cosl ofeach "ltcm"live. Finally,"s part of the top-<!own analysis,,, durninnnl contL'Oh cost curvc**w,,~** plollcd and lhe unit control COol tor each**nll~m"tjve** W'S evaluated_

Two aHe,native, were on Ihe duminonl controls co,l curvc ']lid Ihu, were ;dentitied"s Ihe'**mO'~** COSI**dT~etiv~ all~m'liw,.**  The two 

### BACrNOx eonlrol ahernalives cv"I,,"ICd fur mcn:mcnl,1 Gosl, cncrl;y, .mJ envlronn""nl,,I impacL' 'I,plieable to Millun R. Young .':I.tion Unil 1 were:

•**~clccllve** NOr\_C,lalylic ReduclJon 

### (SNCR) combined wllh a spec,"l fonn ofseparaled overlire air (SOFA) specifie"lly fur lignile-lired cyclonc bUlle" (refe,red 10 as Advanceu SOFA Or ASOI'A); and

• ASOI'A alone.

TI,e lwo ",osr c,,-,t--e[feclivc fcasible conlrol aHernallves forreduelion ofNOx**cm;,~tonS** werc reviewed 10 determine iL1l1c ""e or(he lecbnique or technulogy would r"slIll in "ny slgmfie"nl or unmna] ene'gy penallies or benefits. Polen!i"l inerease in power planl encrgy eon.,uml'tJOLl 01' Llet genenllion rCdUe(lon." for ASOI'A alone, or ASOFA wilh SNCR were relalively small.

The rredicted environmenl,,! lmp"GIS from implemenlalion ufIh" lwo 

### mO,1 eo:;(_erfecrive fe",ible NO

### x emissions cuntrol "1Icm"lives from slighHy highe, unburned c"rbon in the emilled fly "sh, carhon
monoxide, and exces., ammonia (",lip") e11li&,ions was expcclc"l 10 

### he s"'ull 

### ill e"'"l'ari,on wilh Ihc

Ulllns & McDonnell ES-" MilllL,,,ld Power ('''"per.live, Inc_

### NOx BACT Analysis Study**-----------~--~~~-~~-** 

### Excmtivc Summ.ry

significant anticipated reduction in far-field ozone and improvement in almospheric visibility"s a result oflhe overall NOx emission reduclion.

Sler 5 Select BACT Taking into ,ccollnllechnie"1 [easibihty, energy, environmenlal, amI economic imp.cts "nd other costs, the recommended Best Available Control Technologies**~nd** 

### ussocialed emission ,--ales for nitrogen o:<idcs emi<sions pro<!lIced by Millon R. Young Slallon Unit I boiler urc provided in lhe l.ble below.


### NO

### x Emission Control Technology and Rate Recommended as BACT
Control Technolo and Emission Rate Recommended as BACT 12-Month Rolling Average Unit Pollutant Control Method NOx Emission Rate (Ibl million Btu) Selective Non-Catalytic 

# , NO, 

### Reduction with Advanoed 0.355 Sep"raled Ove,fire Air (ASOFA)
This ,""oomm""ded BACT 12-month

### NOx emission rale is based upon a historic pre-eonlrol 12-monlh ba,dine**"V~T"gC** 

### annu"l NOx emission rate usoo in the control amI eost-elTeclivcncss .n"lysis of0.849 IbJmmlltu [or Unit I. The baseline emission was determined from lhe ]2 

### conseoulive monlh period with lhe highest historio summation orNOx mass emissions (pounds) reported for aOlual opemlion between**Janll~ry** 

### 1,200 I and Deceml>er 31, 2005.

To complele lhe BACr delerminalion process, the Consenl Decree (CO) requires lhal '·speeific control lechnologies to be installed and a specific Phase II 30-day Rolling Average NO" Emission Rale 1 imlLation (lbsIMMBlU)" mnst be eSlablishcd Jor each subject cmis.o;ion Unit [CD**Purn~ph** 

### 66, PI: 20]. Because there are expected to be minor short term varialions in operaling condilions where Minnkota has nol, in faol, maleriallychanged any oflheirnormal daily operaling praclices, a margin belween lhe 12_rnonlh overage operaling oonditioru; and the 3lH:lay perinitlirnit is proposc-d, This reconnnended emission rale should be suilal>ly higher such 'hat operalion conSiSlenl wi,h the lechnologioallimiLarions, manufaclun:r's specifiealions, and good engineering and maintenance practices 10 the exlentpraeticablc for the recOlrnnended NOx BACT allemalive would not resnh in an exceedance (violation) ofan enforceable emission permitlimiL

Minnkola Power Cooperative, Inc.**F-~-7** 

### Bnrns & 

### MoDonnellbeculivo Sun\ln.ry NOx UAcr Analysls Sn,dy

TI,e Consent Decree also require, Ih"l the North Dalwln Departmcnl of**H~allh's** (NDDII) NO, llACr Dclmmn"lion**"~dress** <pecillc emls,ion limilalions durin!; Unil SllIrtupS "I Millon 

### R. Yoon); Sialion [CD Paragraph 66, pg 20J. The Iype aOld ,luralion of [iriLlg during sIanup" and lhe limiled ahility ofavailable and fea<ihk l<"<,hnologi,,-, m cont, 01 s!.almp NOx emis",ons, bolh sip,nificanlly influCllce Ihe 30-<lay rollm);**"~~'m);~** BACT NOx emiSSIOn nlle hrnil reeomrnembl for Millon It. YOlln); SIalion hOlkTh. A 24-hour rolling "vemgc NOx en,is.,ioo rate 1imit applJed to ,Iarlup pcriod, i, al.'o recommended for Millon 

### RYoun); SI"lir>n hoilers_

TI,e SEGlJ slurlup opl-raling period i, usually nOI defined in emission permils. Ilowever, lor the purp{lSe oflhis NO, fiACT analysis, Unil slarlup W"S**~efined** "-, Ihe period from**i~ilial** fuel comhuf;lion to the poml in lime wl,en:

• lhe measured Heat Input to lhe boiler on a 6-hourrolling average basis is greall-r lrum or ""(IU"110 2500 million 

### BTU/hr rorIJnil 

### I; Or



### • 11,,, amount oflime reporlc"{1 for the lunge,l individmtl Uml 

### 1 slarl0l' period durmg aoluol operalion belwec-n Janoary 

### I, 20Ul and December 

### 31, 2005 c!up,c" whichever occurs f,rst; or

• foe! filing i, discOHlirllled prior to "allSfiying ellherprcvlOus erile"a.

For MRYS Unil I, Ihe ,ecommended JO-day rolling avcr.lgc NOx em,ssion pcnnit limil r"te thai include, Ihe impacl ofsl"T1L1I'S is hosoo upon recogni7"d operalioll"1 r;,C\OTS and eqUlpmenidesigns Ihal inllucnoc whelhel' the**S~"lrtup** emi"ions Tesull in higkr 30-day emissions compared t" Memal conrinuous ope, alLOll ""cludlllg .,ueh sl"rtup periods;

• Tht ""wmrolled emission ralc (i.e. wilhoul**s~"P"rated** 01'A 

### or SNCR in op<Tulion) "nd ilS varinb,liIy during operJlion from a cold >!armp up lo and including rn"ximum conlinuo", raled output;

• n,e ol'emling eondllion> Ih"l arcrequired 10**~~i."** lor the ,eleele,1 NOx BACT eOr\lrol leehnique;; to bc inilinled and be cffeelive; "nd

• Thc**~ff~~livc",ess** ol"lhe,e two particolar control leclllliqucs Ifinvoked at less-lhau-Ml

### R slc"dy-sl"lo operaling condilions.

• The numberofslarlups and lbeirrange oftypienl duration, per 3D-day**perio~** limc framc.

Tbe Con,enl Deoree aud Ihe 

### EPA', NSR Manual do UOI dc,eribc lhe method for**del~TITlining** 

### a30-{luy Rolling Average NOx Emission Rate permil 1imilalion (CD Ph",c II) lhal reflcels BACT applied 10 MilloJl 

### R_ Young Slalion Unit I. The approach laken in Ihis analysis 

### W"S 10 e,lUblish a hi,lorio pre_ ""nlrol 30·day haseline ave, age NOx emi.,-,io" rate (lbfmmBlll) from lhe 30-conscculive daypenrxl with

BUIlL< & McDonOleli ES-8 Mm"ko", Power ('ooperativo, lno.NO" BACT A'lilly,is SnLdy E"ecutivc Summ,ry

, 

# ,--, 

# :**t~** lhe highest historic unil NO" rna:;S cmi&;ions (pounds) rcportl-.J for octu"l operalion bctween Janua!}' 1,2001 and Dc<:cmbcrJ 

### J, 2005. "Ibis reneels unil NO" emis.,ions thol were generated during period:; of high unil operalions, nol affected by unit shutdowns, stnrtups, ormnl[lInelions. This was lhen oomparC<l 10 lhe 12-monlh historic pre-conlrol baseline nveroge NO" c-mi"ion nile (lb/mmBlu) from lhe 12- consecutive monlh pcrio<l Wilh lhe higllcsl historic unil NO" mo.,,, emissioll5 (pounds) reponc<l for actual operation during lhe some 5-ye"r look-back period. An eSlimate ofNOxemission re<luction for Ihc prop<lsed BACT NO" allcrnalivc opcmling nt the historic prc-conlrol JO..:]ay basdine avcmge NO" emi.<sion rote (IblmmBtu) was mnde. This rate considered recognizod opemlional faclors and equipment <Icsi6'11s appliC<l1o "sleady sL:lle" conditions wilh sustained output olo"e to maximum oontinuous cap"oily ralings. The potenlial impact ofstartups, recognizing opcr<llional and lcchnicallimitations on NO" emission conlml performance, was lhen applied to the sleady-state rate, 10 establish a recommended 30_ <lay Rolling A"croge NOx Emission Rale pcrmil limitation (CD Phase II) lhat relleoLs BACT forMl!lon Il. Young Slation Unil I. This is "ummarized below.


### Recommended NOx BACT Control Method and 30-Day Rolling Average NOx Emission Rate Limit Without Startups
3D-day Rolling Average NOx Unit Pollutant Control Method Emission Rate Limit Excluding Startups (Ib/million Btu) ScJccLive Non-C"lalYlic 

# , NO, Reduclion With Advanced 0.360 Sc arakd Ovcrfire Air (ASOFA)

This**rc"ornmcn~c!l** BACT**)O-<l~y** NO" omi,.,ion role limit i" OO""d upon 0 hisloric prc-conlrol JO-<lay ba.'eline average NOxemission rate 01'0.884 Ih/mmBlu for Unit L The baseline emission was**<Icl~TIIlincd** lrom the 30-conseculive !lay period wilh Ihe highest hisooric unit NO" cmissioru role reported for aclual operalion belween January 1,2001 and Deoember 31, 2005.



## , An incrementol "djuslmenllo the proposed JO..:]ay rolling average sleady-slale unit NOx BACT emission rate withoul slartups of0-36 IblmmBlll [or Unil 1 is**re(;{)mmen<le~** for the JO-<lay rolling overage NO" emission pennit limil period" as delined and applied 10 Millon R. Yonng Stolion. This is summarized in the lablc below.

Minnkol. Power Cooperative, Inc. Bum, & MeDonnoll

# f"""",,, 0 Summa,y Re,'i'cd [01 17/}006 NO., rMCi.\n,L1y<1S**~'"dy**

Recommended BACT**30~Day** Rolling**Aver~ge** 

### NO

### x Emission Rate Limit and Startup Impact
JO-day Rolling Average NOx Impact Dn 3D-day Rolling Unit Emission Rate limit Average NOx Emission Rale Excluding Startups Limit Due to Startups (Io/million Btu) (Ib/million Btu) 

# , 0.J60 +0_041 pe,,'artup
rI,i, recumlTI"nd"d adju'llTI"nt lO [he proposed JO-d"y roll ;n;; ,", e,age <ready.'tate NO, rJACT em;s:;ion rale lLLn;, wilhLlut 'Ianup' i, !la,ed LLllOn average [,i't"';" pre-comrol NOx emission !<,,"S 0['0.766 lblmmDm t"or Unit 1**r~ported** tor Ihe longeST individual Uni, 1 £mrtup p.riOlI <luring; ",:lu,,1 opcmtion bolweon J;lTIuary I, 200 I ami [)o"embc, 31, l005. L'ho," "mi:;:;io"s occurred during Ihe 61_hourJune 27_ 19,2005 ,lJirlup fi,r Unit 1.

A N-hollr roll;ng ;I\'omg" B,\CT NUx cm;s,ion ralo lim;l uppl;cu 10 ,Iarlup po,;"d,**;~** nl,w rccoL1\",cndcd Cor each Lli" the Mil"m R V"ung SllIl;'''\ boiler<,
Thi, LS summarized in Ihe mble below,

Recommended 24-Hour Rolling Average 

### NDx 

### Emission Rate 

### Limit During Startups 24_hour Rolling Average NOx Unit Emission Rate Limit During Startups (Ib/m;lllon Btu) 

# , O.')W

Thosc cmi"iulls ooomrcu dl1r;ng th" (, I-hour JULlO**27-~9,** 1005 slurl\Jp ror Un;1 I,
Compli'Hloo wilh 111<,. "m;ss;on mte would De mo"slIrc<l at 11,0 staok oflhc Un;l, vo,;[,"d w;lh CunlimLl"" Emission Moniloring; (CE,'"l) system,;n accord"nco wilh the referoncc mOlhods ,pcciliod in 40 C.F.R. Port 75, "\ld \\0\1 Id be uOlorminc,1 On " 30 cunsoclLt;vo Op""'ling O"y "n,1 !4·00o"",ut;,"" hour rolling ","e"ge bn,;s,**""p~ctjvely.**

[)\111lS & MdlOJlLlell**~S-l** 0**~IL"nkol"** Po"e, COOp"mLLVO, 1110.

### NOx BACTAnaly,i, Study hoculivc Summary



### A t<inl demonSltslion peri<>d of 

### 18 month, after the completion ofCon""']]! Deoree Phase 

### II NOx 

### emission reduclion syslem installalion commissioning at Millon 

### R. Young Slation is recommcmJcd_ It is proposed 10 alluw Minnkola 10 demonstrate the aClual control sySlem capahililies oflhe combined NOx BACT emis..,ion, reduclion sy,tem. Operating experience during the trial p<:riod will:

• oonlirm**slc~dy-Slate** 

### conlrol performanoe ofthe combinedNOx BACT 

### emissiofis rcduelion syslem;

• allow delennination ofthe ability 10 

### furthercontrol Unit**s~,rl-up** 

### emission,;

• ullow the delcrmination ofthe pmnilled 30-<I.y rolling average NUx 

### emission limit including slartups, shuldowns, and malflUlclions; and

• addres.> the specific emission limilalion, dming Unit sLartups at Millon 

### R. Young Sl.alion**~ndlheir** 

### impuct On the proposed )O-dny rolling**uV~Tage** 

### emission role limit(withoul startups).

Based upon the information obtained during Ihe trial period, finol emission limits can then he delerminedThe mean, thai will be employed to minimize emissions during slartup 

### will primarily be bascd on**oper~ling** 

### procedures, holh before and 

### after Ihe level ofupper furnaee gas lemp"ramres "ml/or heat input rale are considered snfIiciCIlIIO "tart thc 

### NOx controls and operating conditions are conducive for erfeollve emissions reduction. These could be 

### similar 10 

### Minnkota's current MRYS 

### prncrices, or could be**differen~** 

### derending upon Ihe capahilitie. ofIheNOxcontrol. and IheirimpoclS On Unit operations.

MinnkoLa PowerCoopcrativc, Tno_ ES-1J Burn, & 

### MoDofiudl

### -,.-

### NOx BACTAnalysis Study



### 1.0 INTRODUCTION lntroduolion

,

### ... The Millon 

### R.. Young Slalion <>fMinnkola Power Cooperalive. Ine. (Minnkola) and Square Butte Eleelric Coopcmlive (Squnre Butte) inclmlcs lwo cyolone,furnaoe, Iignite-fired boilers prnducing slenm for electric generalion. Bolh units lire North Dakota lignite supplied from an adjaecnt mine, near**Ccnl~'T,** 

### North Dakota.

A Notice ofViolation (NOV) from the Unitc<l Slates JOnvironmenlal Prolection Agency (US EPA or EPA) was issued to Minnkola on June 21, 2002. The NOV alleged thal modificalions illlve been mode al lhe Millon R. Young Slulion lbat would require a construclion permil under New Source Rcview (Cnde of Federal Regubtions40CFRS2.21, und North Dakota Administralive Code NDAC 33-15). As a result of lhis allegahon, a civil complaint

# W", filed by lhe United Slates ofAmerieu and lhe Stale ofNorth Dakola agninstMinnkota Power Cooperative Inc. ("'Minokola") and Square Butle EleClric Cooperalive ("Square uunc'') in thc Uniled States Distriol Court for lhe DistrictofNurth Dakola. A Consent De=J h;1S bee'll entered lhat**rC"J,,~"SelllS** 

### a 

### Iinal negotiated selliemenl oflhe United Slat", and North Dukola's claims again'l Minnkola and Squurc Bul",. The C-onsent Decree requires Minokola and Square Bulle lo perform
a NOx "Top-Down" Besl Available Control Tc"Chnology (BACT) Analysis to dcscribe the emission limit, for NOx ibat will be required at Unils I and 2, ""pressed as a 30-D"y Rolling Average Emission Rale (lb.<Jmillion Btu)'.

Bums & 

### McDonnell was retained by Minnkolu 10 conduct a "Top-Down" BcstAvailable Control T""hoolo

.. ,!, 

### (BACT) Analysis fornitrogen oxi,les (NOx) al lhe Millon R. Young SIStion. uunlS & 

### McDonnell i, n full service engineenng, architeclural, construction and environmental firm. 

### Thc company plans, designs nnd "onSlructs electric generaling facililies and has heen providing enVlronmenl.l1 services since !he 1970s. As port ofthosc services, Bums & 

### McDonncll has ex",nsive experience in permiHing-, Best Availahle Conlrol Technology (BACT) ,Iudies and control lechnology analysis. The r"SulLs o[(he BACT

### analysis arepresented in thi., report

IIn meUniled StIllo, Districl CounForThe DiSlriCl OfNonh Dakom, Uniled Slates orAmerica and Siale or Nonh Dakola, PJ,inlilf" v. Minnkotll Power Cooperslive, Inc. and Sq""re 8utle Eleclric Cooperarive, Defe"daIlls, Civil /lclion No. \;Ofi-CV-034 '!hid -. footnule numbor t, CD pa<agr.lph 65, page 19. Mjnnkola Power COOperalive, Inc. Burns & 

### MeDnnnollInrroducl;OJl NOx IlACT Analysi.,**Sru~y**
Tile primary gu;Jnnce**ulilize~** in**prep~ralion** ofnli, BACT an.ly"," i.' the U.S. EPA', New Source Review Wor1a;hol!J0amml: Prcvenlion ofSigniILc1lnLDcterjofJliqn 

### "IllI Nnnattainment !\reaj'ermittlng, 

### DrJfi. Oclober 

### 1990' ("NSR Manunl").

In Ine next seelion oflncn·porl. Ihe appruacn 10 Ihc BACT An"lysis is de.'cribed. Folluwing Ihal, a qnick summary or Iho**pl~nl** oondJ(ions "nd ,ellOr! 1>"5i, i.' given and Ihen the HACT An"lys;s**h~gills.** Tnc impacl 1'0I1ion oflhe reporl 

### is broke'1l clown inlo**sq"mLt~** ,,,b,ccl;uns. Wilhllllhe lost scclion, (he re.,ul1s 01 all ofIhe BACT Analysi., ,(ep", "re snmrnS!,zed 

### fOi NOx control oplion, for Unit I'., hoiler Ollhc Millon R. Young .%,llUn

.

..

# __ .-

, Cloap'" n**on~e** 1J S. EPA', New SOllre, Revlo,,!:**WUTb~op** Mon",]: P'!-'Vcnlion ofSigniIic"n'**rkLoTj~mlio"** and NOnall";nm,nl Ar<;ca**~o-,n1(U;ng, D",~,** **Oc,~her** l**~90.** Du,n" & McDunncll 

# " Mirmkold**P~_r** C'ooperallve, Inc

### NOx DACT AlJ1llysis Study 'Tn[>-Down" NOxHAC], Anal,!"i' AJlPro,ch

-------

< ••,' 

## ,

# ..

-c' 

### 2.0 "TOP-DOWN" NO

### x BACT ANALYSIS APPROACH BeSl Av"il"bIc Conlrol Technology (BACT) 

### is an emission, limil"lion for**e~ch** 

### pollutanl from a SOurce deLermined to he achievable u.,ing controltechnologie..,{s) Lhal provide the "maximum degree ofemission reduolion

...**takin~** 

### inlo aooOunl encrb'Y, onvironmc"llt<ll. amI economio impuols'"'. A BACT

### review does nol result in an emissions removal efficiency requiremenL TIle gene",lly "ccepled procedures for performing u 

### BACT**3n.ly~is** 

### arC oullincd in lho EPA's ,lmll NSR M<inual. The BACT annlysis for Millon R. Young Stalion Unit I 

### 's boiler NOx 

### emissions was performed in accordance wilh this procedure. The EPA'., drartNSR Manllill OUlline., five hasie Slcps thaI are to 

### be followed in the "lop

### down" BACT eVDlu"lion. These s(;.1" are", follows:
Slcp I - 

### IdenlifyAll Control Technologies Slep 2- 

### Eliminale Technically Infeasible Option., Step 

### 3 - Rank Remaining Control Technologies by Control Effecliveness Step 4 - 

### Evaluale Most Effeelive Controls and Documont Results**SI~1'** 

### 5

- SclecL BACT



### The predefined sleps ofa BACT analysi.< are desoribed in this seelion, and resulls presented. A**~ailabIc** 

### NO

### x control leohniques an<llechnologies**~re** 

### defined, identified, "TId a l,cOOi,"1 deseriplion oflho emission reduolion process and capabililies are reviewed in the following secLion_**Subsequen~y,** 

### lhose techniques and technologies deemed feasible for retrofit applioation are ranked aooording Lo nominal NO

### x controloapability_ An engineering analysis reviews the eslimated capital and operalions and mail\Lemmoe (O&M) cosis for each feasible**allemali~e,** 

### including lakin);" look at B"l"nee ofPlanL (BOP) requiremenls. Following Ihe eOSl imp"el <!elc"TTTlinalion, lhe energy and environmenlul ilIlJl'lel' "re reviewed fore"oh feasible leehnology. :Finally, lhe re,ulls oflhe engineering analyses are tabulaled and a NOx BACT

### selection is recommended foreach unil_



### 2.1 STEP 1 -IDENTIFY ALL CONTROL TECHNOLOGIES 'lbe fir,t step in a "top-down" NOx 

### BACT analySis is 10 

### idenlify, for lhe emissions unil in quesLion, a comprehensive list ofall "available" comro] oplions_ In tho EPA's draft NSRManual, "available conlrol oplions are those air poilulion eontroll<:cOOologies Or leohniques "'ilh a practical potenlial for applicalion to !he emissions \mil an<llhe regulated pollulant under evalualion. Air pollution conlrOllcchnologies and techniques include lhe applioalion of

• Ibid f""tnole numbCT 2, NSR 

### Manu"1 8.1
Minnkoro Power 

### Coope"Ulve, IllC. 

# ,-

# , Bum' & 

### MeDonndl"Top-Du\YJl" NOx RArrAn,lysis Approach NOx BACT Anolysis**Slu~y** produclion proccss or avaibhle methods, sy,tems,**a~d** IcdllliqllCS, indwJing hid cleaning
or treatmeLlI or**"lno~ali~c** fucl combustion teGhniques for cOlllro] ot-the allecled pUlllll"nl"'.
According 10 the EI'A's draft NSR Ma"u"l, "" IcchnoJugy is considered "available" ifII can he ohl"incd by lhe aprlicant throlJgh oommcrcwl channels or is olhetwi<e avnilnbJo wilhio the COmmon seruc "'",ming ofthe lerm"'. 

### AI,o, "a**cOlltlOltechni'lll~** ii;**~onoi,kITd** "vaiJablc, wilhm Ihc conlext**pre,e~lcd** above, 

### Lfit has reached Ihe l;cen.,iJ\g and commcrGwl sales stage ofdevelopment"'.



### In**ord~r** lO idenlify ov,,,bblc NO

### x cmissioll**cOlltJOltechnolot~j~,** oml**lcchni(lU~'** appropriole forpolenli" 

### I "pplic"lion to MIlY Slalion units, the followintl**inforrn~llOn** sources were reviewl"<1 for coal-lired clcclne generaling unil powerplanl<:

• EPA's RACT/llACT/I.AER Clcunnghouse (llBLC) daLaMSC and Control Tttlm"lugy Ccnter (w<ob"l").

• Federal (EPA) and State, including North Dakot" Department ofHealih inlerne, "eb,iLes 

## roc air emis.,ion reImil, and recently-suhmilleJ applicalion" iLlciuding BACT Evalualions [ollu"Iing 

### New Source**Re\'i~w p"x~d"rc".** 

• fcdernl (EI'A and Departmem ofJuslicc) and SI"le, including North Dakola Deparrmenl 0[ Heallh inlernet websile.' lor COrl,entDeerecs ""ued as a result oflegal aclion.< laken hy lhc Uniled State, governmenl ror alleged violallons ofthe**Prev~ntion** ofSig"; [icanl Dclcriomlion (PSD)**provi~iuno** ,m,l Ncw Source Review pl'Ov;,ions uf**Ih~** Clc"n A,rACl, ;m,Vor federally_ ;Jppwvcd ,md enfurccable Slale lmplemenlalion Plans.

• Conh-ol lechnology vendm inlornl3lion.

• Pohli"hed and .vailnhle informuliun from lechlllcal, cngineering, and envlronmenl,,1 consulIanlS. • Teehnie;J1 lilewlllfC found Injournals, report" inlernel**w~b,il~",** nc\v,lcllcTS, proceeding., 0 r techmcal seminar, n"d oonli:renecs pcrlaining 10 "tudie" engince'illg, de.,igns, and le,ling ofair poj]lllion conlrob.

'Ibid, NSR Manual R_5

" Ibid, NSR Manual B.17 'Ibid, NSR Manual**8_1~** Hum, & McDonucllNOx DACfAnalysis Study "Top-Down"NOxDACfAnalysi, Approach


### 2.2 STEP 

### 2 - ELIMINATE TECHNICALLY INFEASIBLE OPTIONS The sc""ond slep oflhe "lop-down" I:IACr process is 10 evaluale lhe available NO" conlrol technnlogics and techniques ilkntific<l in**SI~1'** 

### 1 in lcnru; ofIhe**,pccifi~ fa~lors**  thaI apply 10 lhe emi"ions unit in qucslion. 

### In accordance wilh EPA', draft NSR Manual, "an available lechnology is "applicable" jfit Can 

### be re"-,onably in,talled 

### amI operaled un Ihe suurce lype**und~T** cunsidemtion. 

### A lcchnology lhat is**av~llnbk** un<l upplicable is tedmically feasihle'''.

The EPA's NSR Manuul ,wlcs a technology rnJy be determined 10 be not applicable if"a lechnical**~:;sessmcnl** eon'idering physical. chemical and engineering principles andlor empirioa] data showin!; thc technology would not work on the emissions unilunder review Or lhat unsolvable**le~hnical** difficullies would preclude Ihe successful deploymenL of'he teclmique"'. A1so, a "showing ofunrcwlvnble l"ehnieal difficulty with applying rhe conlrol would con,litule u showin!; oflechnicJI infeasibilily (e.g., sire oflhe unil, locarion ofthe proposed sile, Jnd operaling problems relaled to specific eircumswnces ofthe source)"". Allcr a**del~"ITllin"lion** i, made lhat any oflhe processes are technically inf""sible. option:; arc eliminated iftechnical challenges would preclude or prevent the suco=ful long-tenn use ofthe control optioo or lechnique On lhc cmi:>SlOn unil under consider"lion. This is perfonned prior to any economic analysis.

However, the £1'A's NSR Manual also Mates"

_ ..control oplion:; in"-llpablc ofmccling an "pplioable New Source I'erfonnance SLandard (NSPS) or SlaLe Implementalion Plan (SIP) limit would nol mcellhe delloilion ofBACT undcr any circumslanocs. Thc applioanl does nol need 10 consider !hem in lhe BACT**an~lysis"".** Also, il slatcs "An NSPS simply defines lhe minimum level ofcontrol 10 be considered in the BACT "n"lysis"". The NSR Manual further slales "When developing a lisl ofpo.'SJble BACT alternatives. lhe only reason for comparing control oplions lo 

### an NSPS i, [0 clclcrm;nc whClhcT the conlrol oplion wOlild re:;ult in un l'TIlission level less stringenl limn lhe NSPS. Ifso. the oplion is unaccepLablc"". New Source P.rfonnance Standards (NSPS) lor NO

### x emissioos from 

### EGU:; firing Nonh Dakma lignite
are**o.~** lb/mmBtu. The EPA Acid Rain Program's Tidc IV No", emission limil 

### for Group 2, cyclone-- fired conI boilers wilh oUlpul' greatcr than 155 MWe is 0_86 Ih/mmBtu.

, Ibid, NSR Manual B.17 'Ibid, NSR M.nnal 8.20
" Ibid, NSR Manual B.19 lL Ibid, NSR Manual B.12

" Ibid, NSR M.nnal B_12

" Ibid, NSR M.nu"l B. 12 Min""OI' Po"",r**Coo~eralive,** loc_ 

### Burns & McDonocll"Top-Dmm" NOx DACT Analysi' App""'ch NUx BACTAn.lysi, Study
EPA'.\ deaf I N»R Manual 0100 sinks"A source would not be requircdlo**CXp~Til'll"C** edended Lime <lelay.,
or resource p,:n3Il,es [0 allow r,,-,em-ch 10 be conducted On n new Le<ohnique. Neither's il expeclcd thai an npplic8ll1 wnnld be requireulo cxperience txlenclerJ j, iat, 10 learn how to apply"**l~chnology** Oll 0**lol~lly** new and dLs3imil"r**sourc~** Iype. Co",equenl1y, technologic, in the pilol ,""le IL"l,ling**SLa.~es** of**<levclopm~nt** would nol be considered available for 

### BACT rev,ew""-

Al,o in Lhe EPA's draft N»R M"nu"l is" <],,,,li/iealion for leehnical feasibility, as de,m!:J<',1 by lht: stalemenl ·'Commercial availabil,ty by ilself, howcver. i:; nOI necessarily a snflicieLlI ba3is for concluding

a technology 10 be "pplieahle and therelole technically [ca"bk. Teehnic.l fc"Sibllily, a, de1ermined in Slep 2, also means a conlrul oplion may reasonahlyhe deployed on or "applicable" 10 Ihe source IYpe 'mdcrcomide' aIJOn"".


### 2.3 STEP 

### 3 - RANK REMAINING CONTROL TECHNOLOGIES BY CONTROL EFFECTIVENESS Thc lhird SICp in Lhe ·'lop-down" HACT ev"luation i:; to rank Ihe oontrol lechnologies rcrn"ining 

# "ncr the fe"sibility**"n"ly~i.,** by control efleclivene.". The plIrpo,c or'rrmki"f: Lhe conlrol Iechnologies is 10 e'ta]'l"h a hierarchy lhal**"pl~ecs;J(** Ihe ·'IOp", Lh" comrol teelulOJogy th"l achieves Ih<: lowcsl emissi(lll level"".**~eJeeling** commO" unil< in order to compare emlSSlOns**pcrfonn"n"~** level, amongSI opIion3 i3 one ofIhe Lwo key is..,"es Ihat musl**b~** addICsscd in a BACT analy3ls. EPA', draft**N~R** Man"al ,1"les "il is generally mosl cJTcClivc 10**e~pICSS** cmis,ions performance as"n average ,tcady sl"tc cmi6,;ons**l~vd** p'" 1mil ufproducl produced or**proce~:;G<J"",** For fo%il fuel-lired boilers, ponnds ofllllrogen**o~idc,** pcr "lllt offuel hcal ;npul (Le. lblrnmnruj, is a common means of"ump"ri"g ""d CO!cuIOli"gNUx emis31Ons_
Mnny eontrolledmi'lucs, including both "dd-on "o"twl, ""d inherenlly lower polluling pro"C"'"S CUll perfonn "I a wille range onevels. The EPA'3 deaf I NSR Manual ,Iulc:; ·'Il is nol lhc EPA', intention IO ,equire an"lysis 

## ore"ch po,",ihle level ofefficiency for a conlrol techniqot:, as s""h 3n analysi., would

" Ibid, NSR M"nu.l B_1 S IS Ibiu, NSR M"'mal B. IS "Ibid, NSR Manual B.25 "Ibid, NSfl Manual B.ll Burn, & McDonndl M;JlJ,kola PO"""**r:nnp<mli~c,** Inc.NOx BACT Analysis Siudy "Top-DoWII"NOx BJ\CrAnalysis Approaoh

resull in a 11lJgc number ofoplions"". Also, "[lliInufaelurer's dala, engineering eslimateS, and lhe C};pericnee ofolher Sources provide thebas's for**dcl~TITlining** achievable limits"".


### 2.4 STEP 4- EVALUATE THE MOST EFFECTIVE CONTROLS AND DOCUMENT RESULTS 'fhe [ourlh Slep ofa "lop-down" BACI'**re~ie""** " to evnlt", Ie (he lechmcally-feasible emission controls, begilming wilh lhe moSI effective. Economic, energy, and environmenLal impacts are 10 

### be assessed and quanlir.ed, where possible, in Lhe oonlrol teohnology analysis. The purpose o[ Lheevalualion is to dclcTITline iflhere are any idenlified impaotS (halwonld eliminate lhe top control technology from consideration. 

### 1n the case where the mosl cffeeLive control ultcmalive is detennined 10 incur or produce adverse encrb'Y, economic or environmentnl iITflacl", Lhe ba,i, ofLhe determination is doeumenled, and lhe next mosl stringenl control allernative is evalualed. TIlis analysis process cona'mes**untillh~** eonLrol leehnology under eonsidemlion cannOI 

### be eliminaled by idenlification of"oIl' ""uree_speoifie advers. energy, economic or environmental impacL'.

The economic impuclS are ba'ed on estllllilles ofeap;ral equipmcnl prioing,**procuremen~** imaallation and estimoted operaling and mainlenancc COSts. The lotal inslalled capilal eo,IS along with the operaling COSlS [or**~.,.ch** controllechnology arc summarized in the economics ofeach respeolivc >;cclion. The Levelized Total Annual COSI (tTAC) represenls lhe levclized cost ofprocurement., construolion, operalion and mainlenauee over an assumed service life. CoSl effecliveness ($/lon) ofa controllechniquc Or technology
lS calculated by dividmg lhe LTAC ($Iyr) by**lh~** unnlUll amounl ofNOx removed (lnmJyr). Baschnc 

### pre_ control "missions are**ealclllal~d** using reali.'llc upper bunndary operaling assumptiOnS, considering inherenl physical or operational eonslr.inlS on the source. Plotting ofthe annual amoun! orNOx removed (lonslyr) ven;nS the levelized tolal ,,"nunl eonlrol co.,t ($!yr) [Or the various control options on an x_y b'f"dph anows visualizalion of**l\l~** cosl-effeoliveness. A "leasl--co'l envelope" can 

### be readily identific-d lO indicate the inferior control oplions which ,hould nO! be considered in lhe subsequent analyses. TI,e incremenlal cosl--e[[ecliveness (difference in $Iton) bcrween oonrroltechniques or lechnologies eM also be euloulaled and compared. This allows evalnalion o[ibe dominant controls includcd on the leasl-<oost envelope (curve).

LB tbid, NSRManualD.2J "tbili, NSR Manual ll.24 Minnkol" PowerCooperdlive., Inc. 

# ,., llums & MeDnnIlCll',np-Down" NOx DACTAn.Jy_';' Approach


### 2.5 STEP 5 - SELECT BACT NOx BACT AnolyslS Srudy

The f,nal slep in lhe '<top-down" eVUluaIion process is 10 ,dcclllACT for Ihe**applie~blc** pollulant and emission unit. Per lhe EPA gUJdallee**llocomell~** BACT i, "Ihe mo,1 dkclive eonh-o]ledmology not ellmin:JkJ in Stell 4'''"' The mclhodology**JC"~TlbcJ** above was applied to Ihe Millon It. Young S10llUn Unil I'Rboiler forenmsions ofnllrogcn oxide"_

_c_

ll"rJl5 & McDoTIndl 2-6 MinnkoLO Powel Cooperative, Jnc,

### NOx BACT

### Analysis Study llACT**A~alysis** 

### forMRY SlauonUnil J

### NOx Emissions


### 3.0 BACT ANALYSIS for 

### MRY STATION UNIT 1 NOx 

### EMISSIONS The approach laken in Ihis 

### BAcr analysis for Milton 

### It. Yotlng Station included a technioal analysisof demOnSIT1l1cd conlrolaHemalives for NOx 

### emissions. This upproaoh followed the predefined slep.s ofa 

### BACr analysis process as gcncrully dcscribed in Section 

### 2. POlential 

### NOx control techniques and**leehTlolo,~ies** 

### W"!'C idenlified, and a leehnical dcscription of1he emission roouclion prooess and capJ

### bib' lies were provi<k:d. SIlb6equcndy,**lho~e** 

### techniques and lcchnologies deemed available and feasible for re1rofilapplicalion were ranked according to nominal NOx 

### control capability. The enginecring unalysis 'hen developed the ,,",tima1ed c"pitJI and O&M 

### costs for each aHemalive. including taking a look al Babncc orPlanl (HOP) rcquirements. FinJlJY,!hc oosl effOClivoness poinls for each feJSible leclmology werc plolted, and !hose thul comprise lhe domimml controls curve werC identificd.

for the feasihle lechniques and lechnologies considcred 

### for deten-nining 

### NOx control cost-effectiveness for thc two steam cleolrio generating unil' at the MilY 

### Slalion, CSI;mates were produced for predioled NOxn::d"olions Ihal represent aohievahle long-term expectalions ofthe alternal,ve reduction techniques and lechnologies being-prcsCillcd in lhe tc"Chnicnl analy,i.. Each wCTC 

### lubulatcd and gnphed.


### 3.0.1 EMISSION UNIT DESCRIPTION MiHon'R. Young Stalion Unil I is owncd Jml opcmled enlirely by Minnkota_ MRY Station Unit 1 includcs a Bahoock and Wilcox sleam genenlor installed in 

### 1970_ The slearn generator is a lignile-fired boilcr with mulriple cydolle-fuffiaoes installed in parallel using bDlanced-drar, and natnral circulalion. Original unil 'lcsil,'Tl steam generating capacity is 1.714 

### million Ibslhr ut 1,920 psi Wilh Dfuel heal inpul of 2,510 mmBlnfhr. 

### The boileris fired by seven ten-foot diameler cyclone burners. arranged ··thrcc over four" ucros< lhe front wall oflhe lower furnace_ Thc unit has a tnhular airhealer ,n,lalled between lhe boileramI lhe flue gas ductwork lead,ng 10 the electrostalic prccipilaLor (ESP)_ Exhaust gases leave Lhe airheater and pass lhrough an ESP for pm1iculalc collection and removal prior to Lhe lWO induced dron fang (installed in parallel) which discharge 10 

### the stack. Unill has 

### a nominal 235 MW nel design output eapacilyraling, is typically capable ofsu.,tained outpul ofapproximalely 253 

### MW gross, and has an uHimale shorHerm maximum gross output (URGE) rJling of278 MW_

Mitmko!a 

### rowerCoopernllvc. Inc Burns & 

### McDorulellBACT An,ly<i., r", MRY Sialion Unill NO, Emissions NO, R/ICTAnaly<i, Sludy

The EPA's Tcchnical Snpport Ooc"mcnl"' puhliHhed in the E<lockcl 

### (EPA', ;nlCmcl website) lort1lc Filllli BART Guiddines li,t" nnmeplale**slcnmlurbinc-~cneralor** capacity ofMRY Slalion Unil I as 257 MW fgros,), which W:Of; a,sumcrl for calcnlating capItal cost cslimalos [0' control altel'llaliw,.

Tilo Unil 1 borle, at M.R. Yonng SI"lion ;nd"rlcs a umg"e cu"l**cumlillUnin~** 'yslem (drying, "rlIshing, and feeding) 

### for each cyclone furnace spc"ific"lIy designed 10 ald in proper coml""lion ofthe lig" ile Iud. n,is rTlClhou offiring solid fnel sit,nilicantly inlluence, Ihe rcsuhlll]< nilrop,cn oxide conoe"lrJllOn ofIhe fille g<tses emliled from 

### Ikboiler,;.

Milton R. Y**olJn!~** SI"lion Un;1 I'R hoikr <lcsign, combuslion performance, and 

### NOx emissions are**dOJ1lin"l~d** by Ihc compo"i,ion an,1**~ombu,tion** chnraclcrlSl1C, oflire North D;,kota ligLlilC sOJpplic-.:l solely frum" surface mine adjncenl10 lhc plant. Tni& mino is Ihe only sopplicr ofsolid fuel for Ihia sl"lion, as Ihcre are no railroad**facilili~s** provided 10 sCTvicc thc Millon Ie. Young plant Norlh Dokota hgnite ha< high moisture amI high so<1ium conlenl, moucrJle higherhealing values, and tnn hove a widely variablc anJ high 

# ",h eonlc-nl compared 10 olher coals. The.,e oharnclCri,llc, create difIiculties in promolin>: eon,islc-nl, slcauy comhu."jon nnd ,lag formation in ll,c cyclone' bomcn.. II also rerullS in prmlucing a TIyash lhal has ReVere <1ep"'ition charaClcrislies.

TI,e de,ign urnl upcraling condi'ion, for Ihis study are pre,eTlled in Table 

### 1·1. 'Jhe hislorioal avcnl!o'C li!o'T1llc cool nnnly", i, shown in T;lble ]-2.


### Table 3-1

- 

### Unil Design Parameters Unill lksi nllnilO**Cr~liJlu Ch~raclec;sfks**  Do,; Il noiler Type Sllbcriu"I'" O)mb\lSI;On Sy'lem Cyclone Number ofCyclnne,;**'"aJlgemL"1l~** localion 7; J over4, lmnt ULlil DOSlgn Cap,eityEleclric.1 Ou \II''', MW**(neL!~r",,)** 2)5/257 ,neod drafl sin Ie dIU 

## ,u erhealed 'learn wilh**.,in~k** .,", c o[.,loarn Ieheal. (I) Bal g Ill, P g (2) The,c values Wtre eslabhshed hy Ihe original ct]wpmcntTrulnuL.oluror.<, r,ior 10 Con>lruo[ion.

" EPA Dockel OAR-2002-0076-0446 Technio.1 Suprort Doc"lTlOfil [or BART NOx Limil' for Eleclric Genomting Units**£~Ld** Sprcuilihccl (,11512005, pO,led 011 their we!>-,ile: [WillEDOCKEr ot hllp-ff dockeLeI'•.gov/cdkpuhidolEDKslamternDo10ilView'!obj**ecild~O'lOOO** 7d4 80M562b; Ihis l' OSSO'ialoo wilh EPA Aoid fuoin Progr-"rn C1e," AirM"rkel> Divi'ion, Technical Support DocuIDenl-**Melhod010~y** Jour Developing DART NO, Presu"'pli,'e LimilS, June 15, 2005, OAR_2002-0076_0445

" Ibid, fOOlllOle number2, NSR MOIl"al**p,~e** B.ll
Bum' & MclJo"ndl 3-2 Minnkola P"WIT Cooporalive, Inc.NOx 

### BACfAnal}$is 

### Sn>Jy BAer Analysis rorMRY S,allon Unit I NOx Emi"ion'



## 3,0.2 Table 3-2

- Historical Average lignite Coal Analysis Lignitc

- CcolerMine**A~er.ge** UJiitnale Coal Analysis: 

### ("-, leceivcd) %l> IlIaSS

Moisturc 37,29 Carl>on 38,69 Hydrogen 2.50 Nilrogen 0.57 Sulfur 0.81

### ~" B,74 Oxygen ll.40 Total 100.00 Highorf10aling Value, Dlu/lb 6,662 

### NITROGEN OXIDES EMISSION FORMATION Nitrogen oxides (NO)!) arc produced when nitrogen 

### TIl the fuel and eombuslion airan: exposed to 

### high lemperature!;. There are lwo prima ry 

### sources ofNOx emissions, referred 10 a.< 

### '1henrnl" NO)! and "fuel" NO x. 

### Thermal NO

### x emissions**~re** 

### pm<!uood when**elemen~,l** 

### nitrogen in Ihe "ombUSlion airi' udmilled 10


### a high lempe' alUle zOlJe alkl 

### oxidi«ed. Fuel NO

### x emissions arc ol"C"dled**d~ring** 

### Ihe rapid oxidalion oflhe fwel containingnilrogcn compounds_ For m(}.';t coaJ_lired unils. Ihennni NO x 

### emission lypically rcpresenls a

### pproxillliliely 20"10 

### and fucl NO x 

### about 80% ofIhc 101,1 NO x 

### formcd_ Nitrogen oxidc (NO) is lypically the mosl prcdomi".nl form ofNO 

### x emissions from fossil fllel combuSlion. ,long wilh nitrogen d 'oxidc (NO,J_ "fhc fomJation ofthesc compounds in ulility powerplJnI boilers is sensitive 10 

### lhe melhod offiring and combuslion controls utili·led. The lechniQues employcd form,xing Ihc combusllon air and 

### fuel. which creales flames "nd high lempcrnture combuslion products,resulls from Ihc rapid oxidizalion ofcarbon. hydrogen, and olher exolhennic rcactions_ Cyclone-lire<! boilers, by design. ereatc inlensc hcat ",le;,se rales 10 

### mell "nd fluidize Ihe co"l ash introduced inlo thc barrel-shaped furnaces. This produces high lemperarure flue gases and ",sulls in very 

### high uncontrolled NO

### xemissions. TJ,eamounl oflhennal 

### NOx 

### emissions produced by cyclone boilers can be consid"'<lbly highcr Ihan fuel NO)! emissions.


### 3.1 IDENTIFICATION OF NOx CONTROL OPTIONS FOR MILTON R. YOUNG STATION Thc first 

### step in lile 

### MCf eva! nstion is to identiJ» sll "dernonstr:lted and polenlinlly applicnble control leehnology allernatives"" ,ccording 10 

### lhe EPA

### 's draft NSR 

### Mannal. In identiJYing control lechnologies. "lhe applicant needs to survey Ihe r.rnge ofpotenlially "vailable control oplions'""'.

,. Ibid. NSR Manual page B.11 MinllkQI. 

### Power Cooperative. 

### Inc. Burns & McDunneilNOJe BACT Analysis SJlldy



### 3.1.1 REVIEW OF RETROFIT INSTALLATIONS The BACT**Jelennina,ion~** li,le<l ill the**~.P** A', HACTITIA(:T/LAf'.lt C!eal'inp,house (RB1.C) dalabase arc 

### f<1r new faeililies. The Millon R. Young Sl<l\ion**i~** 

# 0" "",,isling powerpl"1\l beilil)'with lWO coal_fired HJUs. A BACTev"lunhon forretrofilling control equipHIL"l't 10 c""l-[ire,l i:Gl

### J, in an c""ling facili,y will be sub,lalllially dlffc'un lhan on all"ly,;i, for in,lallinfl comrol c(luipmenl on ooal·[ired EGlh LLl a
new lJcility. Con,equ""tly, in po['fo'mmgthe BACT "nuly,i, for exi,linR boiler, al MIllOn 

### It. YounR Sialion, il is imporlant lo l'C"iew pO\>lerpbnt f"cililic'",**~speeiolly** eydnne-nred coul hoilers, whiohha'" rellolitled NOxeornroI e()uipment inrecent yea".

In 1998, EPA "sued a No" 311' (Slale lmplemc"l'l,,,ioJll'lan) calL UndEr the SIP c"n, Hlilily boiler, illlhc ",a'iem Uniled Siale, were required to sllbslantially reduteNOxemi"ion' during lhe "owne ,eaSOn"_ 

### '11", tomplianco 

## wle l'or Ihe NUx SIP tall is "'by 

### 31, 2004. l\. h;flh**pcrt~nlage** ofthe 

### fIT""**eketri~** generation ["ellilies in Ihe**~~slem** Uniled 3Iale., have or**~re** in lhe luoce" o[rcllolitlingNO

### xeOlllrob to comply wilh lhc**NO~** 

### SIP c"ll. The ErA's NO" 

### Slt' call was nal aj1plLcahle 10North Dakol" ulility boilers.

There "re a numbcr o' fossil fuel-LLred EGUpowerplams around thelJniled Siale, tllatl""e imp1emente<1

or arc planning 10 ill1plemenl modificalions to reduce NUx emi"i"n,. The NUx em;"ion control syslem ".' installalions are in**r~sponse** lo ACId Itain rc-quiremenL,. EPA', NOx SIP cun, il,e Clean AIr**IDler~lale** Rule (CAlR), the Regional Hazt Rule (lll-m), und local regululioll'_

In addilion lu Ihe [aeililie, lha' have h"d 10 r",lrolil emi"'iOTI' controls"" a rcwll 

### of lheTitlc IV Pun 7(, Ao;d Rain L'CquiremenLs and/or c1'A', NOx SIP call, a few inslullahons ll"vc had l" retrofit conlrol, in recentyLllrS as Ihe res\llL ofCO\llt deci,ions resulting Itom liliRation "nd**":gul~lory** aclion. None oflhe boile" a"ocLaled Wilhidenlilied cunsenl**de~r"cs** are oyc1one_rned. They urc abo localcd in uregion requiring oompliance Wilh an EPA-Jpprovcd Slate lmplementation Plan [or nitrogen oxides emi.,ions control> (i_e. NOxSIP c"n). lis menl;one,l abow, Norlh Dakota uliliIYboiler' were nol ,utricct 10 lhe**EPA'~** NO" SIT' calL



### .,-4 MinnkOU1 PowerCoopcraLive, Inc-NOlI BACTAnalysis Study BAcrAoalysis rOT MRY Sr:uion Unit 1 NOx Emission'


### 3.1.2 POTENTIALLY FEASIBLE NOx CONTROL OPTIONS FOR MILTON R. YOUNG STATION A review ofa\'ailahle infoTTIl"(ion On relrofil imtall"lions pcrfOmled at utilily unci ind"'trinl cool·fircd powerplo.nts during the ]XISl fifteen years was undcnaken. NUx emission control lechnologies and lechni'1oes Wilh pnlenli"l**"ppli~aljon** lO 

### M Llton 

### R. Young SlUtion boilers were identified. and**ar~** listed in Tahle3-3.


### TABLE 3·3
- Potentially Available NOx Control Technologies Identified for BACT Analysis NOx Control Tctohnology
Pre-CombuXlion Controlx Fuel CleaningIBlendinglSwilching Combustion Conlrols Basic Comhu'lion Conlrollmprovemenls LowNOx Burners (LND) Sg>araled Overfire AiT (SOFA)O) 

# - Flue Gas Recirculation Fuel Rebum



# -- Oxygen_enhanced combuslioo (OEC) Walerlsle,m injecl;on (combustion lempering) Post_CamburtioD Coutrols SdecliveNan_Calalytic Re<1uclion (SNCR) Seloolivc Catalylic Reduclion (SCR)**El~lra-Colalyric** Oxidatioo (EeO ) NoleS; , >< ,. c rom", orlhe idenLiHed [ocho; ucs. he"'" b" q No' all ,ariaMo, orcombin,lion' ",e induded. (I)

- SOFA technologies ineludeBoosted SOFAaod RutaL;ng Opposed firotl Ai, (ROFA) (2)

- SNCR lechnologie, ;noludeRich Reagoo, Jnj,euon, 'nd Hyd,ocarbon.""h,n=l SNCR. eOJnOl"re,oJlyavaila hlo

.. "NO.Sl"Thi,.. (1)

- Mulli_polluLaIlL con'rol'echnologycurrcnllynuvercommercial develop""nL hy rowerspao Corp.

A compTchensive lile"'lurc sC"Tch, with sources induding**le~hnic"l** papers and present'lions mode a\**confercn~es** by nationally-reoognizc<l technical organi?.ations. utilities and olher]XIrties involved with design, oonstruclion. and lesting ofNOx**~ontrollechniqu"",** plus hardw<lTe supplier cl<pcricncc li,IS, was pc,fOTTIled. TI,e Tesulls oflhis search are presenled in Appendix A2, which indudes a summary of various selecled U_S. NOx emission TccluClioll TClrolil projects.

Minnkola PowuC'.oQpcrnLivc, Inc. Durns & McD<:mneUBAITAn,lyslS [or MRYS'a,ion Uni' l NO" Emission'



### 3.2 FEASIBILITY ANALYSrS NOKBACT An,ly.,i, Srudy

TILe second &lep of**Ih~ "lop-<lown~**  BACT rroce" i.' 10 ev"lt"Jk Ihe control rroce""es that ha"l' bcm identined and delel'lni"e iI'a"y or**lh~** processe' arc lechmeally inf"",ibk,

An availahle leehnology is "applicahlc" If11**~"n** be rc",onably bc imlulk<J 'lnd opemlcd on the**soure~ lyp~**  "ndlT**~ons](krJtion.** Also," conlrol lechnique i.' considered available ifil has' each",l Ihc 'lage of licensing and commercial avmlabil;IJI. For lhe**purpos~s** o[lhi, aMlysis, the ,erm "wmmercial" is further defined to mean "capahle ofe,tahli,hlllj{" [,,11 cOnln,"I",,1**a~'IT<mcnl** wilh "ommcrci"1 nnd perrO! mance !\uaraTl'ee.' snl'pnrted hy**apPnJpriul~** limn"ial backing" for Ihe**J1nl'lemcn~'lion** offulk"ale,**tull-,im~** oyolemS of'he leehnig"e or tc"hnology applic"lion. A technology Ihal is availablc and "pplieablc i, Icchni""lly fcusibk.

There are lhree basie**cale~orje"** ofNO

### x emission**~ontrol** leclmiqucs und**t~chn(ll(l8ics;**

• Pre-comhus'ion conlrOh;

• Combuslion conlrols; and

• Po.,t-comhuSIion controls

Uncontrolled 

### NOx cmi"ions from a coal-fired electric tL"!lcl1,ling unit al'e hJghly del,endeol OOlype of firing meIhod, amonnt ofsolid fuel Iired per "nil lime and furnace volume,**nmllh~** fuel's basic comhmljon propenie._ and elemenlill oomposilion. The basic melhod, [or rcducliuu ofsuch emi""ioos;

• ei'her pLevenl p"llUlio", i.e- 

# "'C inhcrL"Illly ]ower--emitting procc",cslpmclices wluch pr(lllucc [ewer 

### NOx emissions**durjn~** the [l<lwer**g",,~r,llion** prucess; Or

• involve improvemenls 10, 01' pmvide new add-nu coutrols IhM, reduce emiSoions nfier lhey are prodnced hefore lhey are emi'l<:,l from lhc fncility; or

• are combiillliious ofil1heremlylower--emilling

# proC""'"" al1d add-on controls.

MoSi of'he identjjied OO!lIml oplions havc bcen "ommercially-avaibbJc,**insl"ll~d,** and operati"g in m"ny full-scale, pCrrn"nL"Tl1 wal-lired ulility boiler insrnllalions**il1lb~** Uniled Slales for fiw**y~"rs** or more.
1'rc_wmbustioLl CO!lIl'Ol." snch as Iud ,wil"hin;:-, fud blending. and fuel cleaning have l,ee" pra"liced and I'e, formed nt numewus \Ilility powcrplanls, typically lor**up~Tational** and suIrur emi"ion' contl'Ol
reaoons.
Burris & McDorurcll 3-6 Minnkolrl rower Coopcrdlivc, Inc.NOxDAcrAnalysis Study BACTAnolysi., for MRY Stalion Unit I NOx Emi"irm<

CombuSlion conlrols, such as 10w-NOx burners (LNBs) Dnd ovcrfire airsysterru;, UfC vcry commonly applied 10 reduoe NO, emissions ITom fossil fuel-fired powe.. planLs. Low-NOx Burners arc lypically uppli"u 10 pulveri:led co.l, g""COUS**~nu** hquid fuel-fired boiler,;. They are not applicable to cyclonc-firell hoilers. Flue gas recireulalion (FGR) has been pracliced and performed al numerous natul1ll**~as** and fuel oil-fired ulility anll inlloslriol**powerpl~nt:>** for NOx emi:;:;ion:> conlrol reason". On**Iar~c** coal-fired utilily boilers, FGll has primarily been applied fOT sleam lemperalure conlml pmpo""s, no1lor emissions control. Conventional Gas Reburn (CGR) with overfJre air has been installcd and placed in commercial operaliOT\ on ,everal cyclone_lired boilers, primarily in ,he eaSlem region oflhe Unitril States_ Coal Rcburn (CR) with uvc"lfi,c uirhas bcc"ll su"ccssfully**dcmonslral~-o** on two cydone-fired boilers ond comme,cially installed on Ihree pulverized coal-fired boilers in the Unilcd SlateS. Comhu"lion lempering (water/steam injection) has been lesled bul has not been continuouslypracticcd on cyclone-fired coal boilers. Oxygen_enhanoed comhustinn has onlybeen demonstraled and/or in,tallEu on a limiled number ofpulverized coal-fired powerplants, nOl on any coal-fired cyclone boil"".

Selective Calalytic ReducLion (SCR) and Seleclive Non-Catalytic Rcduclion (SNCR) are posl-combuslion

. technologies lhal have been applied predominantly on eastern or midweslern bill,minous**eo~l-fi,ed** boi]",s. Others, mnsHy comprised ofa combination ofavailable emission reduclion Il"Chnologic." are oflm rcfcncll 10**~s** "hybrid" or "layered" conLrllls_ V**ari~lions** ofSNCR, such as Rich Reagent Injection

, (Rill) wilh and without SNCR, have only becn iru;lalled or demol1slrntcd on 

### ulimited numbel ofcyclonelired boilers_ Other lechnologies, such as Fuel Lean Gas RebumTM Wilh SNCR, hydrocarbon--enhanced SNCR (commercially available as NOxSlar'M), and Convenlional Gas Reburn with SNCR have only been demonstraled and/or inst.J]ed on a limi,ed numbCI of**pulve,iz~d ~oal_fired**  power plants_
Emergmg posl-combuslion multi-pollutanl conlmlledmologles, such as Powc"lSpDn'5 Elcclro-Calalytic Oxi<l.lion (ECO'"'l, which inolude NOx oonlj"ol, were also illcnlified_ lbese are lypically in the large pilol-scole**commcrci~l** lIevclopment phase, and have not been successfully demonstrnled on a full scale basis on any pulverized coal, cyclone, 01 ci,culatlng Huid bedhoilers.

In most ofthe combinalion 01 "layered" and emerging control cases, the NO" conlrollechnology has been lIemonsu-ated 10 he capable ofcontrolling lhe Largelcll pollllLanl(s) 0" either:

• a fllll-s""lc b.si" but only wilh temporary equipmenl; or

• a full-"cale basi" wilh permanenl equipmenl bUl in a limited number ofinstallalion,; or

Millllkota Powor Coopcrativo, Ino. Dllms & McDunndl!lACfAnalysis fur MRY Sialion UUil 1 NOx Emissions 

### NO, nACT An,lysis Sludy

• Wilh lef;.S lhan full-scale and fun_lime applioalion.


### 3.2.1 SUMMARY OF RETROFIT INSTALLATIONS OF NOx CONTROL TECHNOLOGIES The, e are a ll11ml,er or bcililJe, around ule cnuutry lh.l have- implemenled or are plannmg 10 illll'lemcnl rnodilic;]lions lu**rcd,,"~** 

### NOx**~mi"sion"** 

### T"ble 3-4 summari""s lhe various 

### NOx emissiou**~ontru!** syRtem inslallalion.' elll ,enLly ;nsi.alled, or lhal have !leen demollSlraled 011 a lilli-scale. shorl-lenn ba,is, in
respunse lu Acid Iz"in rc'l"lT"m"nls, EPA', 

### NOx 

### SIP ""11 am! local rcgululions, Or a ulilily invesligating Ihe Icchno!o!l}'.


### TABLE 3-4
- Identified NOx Control System Retrofits on Cyclone Coal-fired Boilers

No.ofVnllsll) C}'etooe NO

### x Conlml Teehnolol:}' Descriplion


# , Fnol Swilohing/Blending ji)V'-**~-------~** --_. --------- Sep,,,.led Ovelrue Ai, (SOl'A) 

# , Solcrtivc Non_CalalJ'lio Rcducllon, wilh or w'llwm SOFi\

-**_._----~~--** ._- . _- ...

# _._ . 

### i ') Rich Reagenl Injeclion. WIth SOl'A 

# ," Convcm;oTIal fuel rchum (pulvcTioed or mi" ollized coal, g"j, wi SOFi\

--
_ 

## .. - --**~.~** 

## ----1','1 Fuel le.n g.s**reburr~** wiul or wiUloul SOFA

-- 22(0) High-dustOT low--d1lS1 SCR, wilh OJ WIU101il OUle' lechnologl.S



# " Tail.g,; SCR, wilh or wilhout o!her leehnoloRies 

# , Th;, li51 ofkoOWil NO, <onlrol relrofil in'lall"ion, i, nmanl focused on uni"

# ,n Ihe Umled S""c, ( ) p y 

## 'n",. onay b, olher II,"allallo", Ih., 

## are "onllar bUI weo. "", ;<I"n"I'OO. (l)

- In,IAll"d 1o, NO, "ml",l (w,'houl i"d ",""m). A lisl ofknowTI cyclone bud"rSOrA m,I;,llA',"n, ;> meludoo on IIpprnd,x A2, 

## m· Rill ha., only bee" demonslrated wllhlemporary 'quilm"" r", 1",ling. S", le<l1O;e,IIII""U" "re"n'"';n APl'","I" Al and A210r "eta;I,. (4)

- So,,',,1 co;]v,nllOn,1 ct'.1 lind go>**"'~IIrn** rel'ulil, h.vc d,seontJllu,drebum demo"'Ir"io" orrolll;ne opmll;on. S"" rochnioal L,'eralnrc Rofm;]cc li51 OJ\d Append,,!d fo, r",Jheo delails. (5)

- Only one CA,mplc orfod hn**~""** Teb«m relrofrl (wilhoUI Of A) on 0cyclone-fired boilerh" bern denlOn'l,aled. Th" sySlcmwas insl,lIoo for ,hon-'crmreborn ",,'ing and ha< been ,emovoo. (6)

_ IILgb_du<1 SCR lechnology h.s bccu ,.Irofrllcd on six",," IIS "yd"nc-li,ed holl"". aJl bel;eved 10 have SO,A,**I."w~jn,l** SCR, HI U.S. I"vo only I"e" ;".<Ialloo only on pulverIZedcool-fi",d 100;1,,,,,**nO'"~** ,m 'yd"""" Ono lail_ gas SCR 1I111,llal,on on a co.l·frred eyclouc [>oiler fou"d '" (;"""ny; "one III thc U.S. Sec lecbmcoll"eoatn", "·r'",,"',,,;n Apr'''',];' Al ami AI [or d,I"I,.

A mure detniled deocriplion ofthe various control technolob'Y Tclrolils and lheir**cJaim~d** crfeCliveness I, included in lhc lcdmieal de,criptions amI**rcf~Tt-'nce** hterature In the lechnical feasibility assessment of

IJOIn, & McDolUleil M1Onkoi. PowerCoopeIllIJVe, In".**N()~** 

### HACr Analysis Study BACfAnalysis forMRY Sr-t;onUn;l 1NOxEmi,,;on,
Appendix AI, and Appendix A2, which includes a Sllmmary ofvarious seleeled U.S. NOx emi

.. ,ion reduotion retrofilprojeels.


### 3.2.2 SUMMARY OF FEASIBLE NO)! CONTROL TECHNOLOGIES FOR MRY STATION

\'-'.



# - -"'- 

### One examplc offuel swilching applied to a cyclone-fired boiler was idenlified. Ottertail's nig Stone Unil 1 wa.' originally designed lo bum North Dukota lignile and was swilched lo we,lcm subbiluminous (PRE) coal for reasons unrelated to NOx emissions redllclion. Big Slonc Unil I and MJL Young SlJlion Unil2 have ,imilJrboikr designs, and MRYS Unil I', boiler is approximJlc1y 60% as large as MRYl> Uoil2's boiler_ Thus. eonv"",ion ofMillon 

### R. Young Slation Unil I·, hoiler to fire PRE coal Ora lignileIPRB blend i, teclmieally possiblc.**Th~rc** 

### are nO railroad facililies provided to serviec lhc Millon 

### R. YolJl1g plant. Additional opernlionJI and capital cosls 10 

### bring in large quanlities ofPRE coal will be significant. BJSed on u comparison ofavsilable emission dala between Ollcr1ail's Big Stone Unit I and M.R. Station Young Unit 

### 1, lhere is no expeeled reduction in baseline (i.e. unconlrolled) NOxemissions from -,witching to PRE from lignile al MiltOn R. Young l>lalion. AlLhough fuel swilching at Milton 

### R. Youug SlUlion is lechnically feasible, lhis allernalive will notbe economically compelitive wilh**olh~T** 

### NOx control ICchnologies lhat offerbetlerresulls for J much lowcr combination oroapilJI and opcTJlional ·cosls. For lhese reasons, il has not heen cnnsidered flllther as an effcctive NOx emissions control oplion [or

### MRY StJlion Unil I boiler.
Sqmmlcd Oyerfire Air (SOFA) is the mosl commonly-applicd,**~ombusllon-fe1alcd** 

### NOxemission reduction Icclmology that has beeLl pl'Oven effective on cyclone-fired boilers. A version ofseparated overfire airspccifieally dcsigncd [or increased NOxemission reduolion perforrnunee ror Iignile_firc(l cyclone boilers, referred lo as "AdYHneed SOFA" in this analysis, can be inslallcd On bOlh units al M.R. Young Station. n,e Imtential operationallimilation, mentioncd in lhc delailed feasibiliLy diacussioru; induded in Appendix Al for deeply air-staged cyclones assooialed wilh sepaTilled overfire air are cJlpCCled to limil Lhe control eITectivc-ncss urlhis Icehniquc, alonc and in combinalion wilh other reasible NOx control options.

SeleClive Non-C".atalytic Reduolion (SNCR)**le~hnology** 

### is a [orm orposl--c:ombuslion NOx emission control thaI hus been succcssfully applied on numerous utiliLyboilers burning caslernbiluminous coal, midweslern bituminous coal. and, (0 a ksser CJlICm, "'CSlCm subbilUminous coallo reduce NO" emissions. SNCR has also been used on rue! oil and naluml gas-fired uniK SNCR doe, no! appear to 

### he

MinnkOI. PowerCoopelalive, Inc. 

# ;-, noms & 

### McDonnellnACTAnal)"';., fur MRY Smlio" T Inil I NOx Emi<,'io"-'**~--~~~------** NOx BACT" Analy'i'**Sru~y** dependenl**~ireclly** on lhe lype o[bomers (wall-fired, langent'.lly_fircd, and "ydonc-fired) c-mploy"d in lhe boiler' where il h'," heen Lnstalbl, wilh or 'vilho"l air-slaged combu"llOn wilh ove,li,e air Ln (illl OpenlllOn, Tru' conlrol lcchnology adds un.'a (or ammon;,,) rcugcnl 10 the hOl [unlace ga",,"' m the "pre, [umace to chemLcaJJy reducc nilro;:cn oxide.'. SNCR wa, consLdered l"eImioolly ro""ibl" [or apphc;llion
on bOlh "0;1$ "l M.R. Young Slation. SNr:R oall he operalerl wilh mld wilhoul SOFA VariaL;ons of SNCR technologLe., "uch af< Hydr"earbon-enhanccd SNCll (JlE-SNr:R) a"d**"RolarJli~"** have been Ln,l"llerl On pulvCTlznl coal-Iircd boilel, hut are nol I,mven Oil cyclune boile". Thi, is described in delail in Appendix Al.

Rich Reagem Injeotio," (RRl) lS" runn ofSNCR underdevelopment .,peoilically inlen,iL,,1 fur NOx emissions oonlrol On cydone boilers. A, ofOctoher 1006, RRJ has been d"",onsln'led bill has nol been commercially insl"lled and placed in conllnuous operalion On 

### ucydone-fired boiler, e,pecially one burning coal wiLh high fouling aLld .,lag**Icmp~T11l11rc** ,cm;ilivilies associated with lignLle ,ul'plied rrom lhe Center mine. RRI adds agucOllS urc" reagenl lo lhe hoi furnace ga,e., l\e.r lhe cydoncs,**whi~h** mu,l be devoid or frce oxygen ,n orUcr lu "void oxidalLon ofthe urea whioh wi]] incrcu,e NOx**<"fl1i'~lOm.** lUU '" eomi,k,"d t,'("hnie"lly infeasible for applLcalinn on the cyelone boilers al lhe Millon R. Young Slatlon al lhe present time. ThLS i.' de.'cnl"'d lJl dclail in Appendix AI.

Variou" (orms 

### uf fuel**T~bum** wilh and wllhoul overfire air are 'YPeo ofcumblislion-TClaled leehnologle" lhal have been demonstraLed and oornnlL'Tci"lly insl"II",1 on plilverized coal, filel oil-fired, .nd oydone utility and indusllial boiler,. Nalural g"f<-consumin;: vorialions BUch as Convenlional Ga" Rehurn (CGR) and Fuel-J.ean (,as Rehorn (1'LGR"") havc bcen applied 10 cyclone hoilers hw "Lng bilumiTlOU' ,md suJ,billlrn;nou, coub, High copil"1 cosLs expected for il\"la]];ng" nulu[1,1 g'" pipeline and high operaling OOSls fTOm comumplion oflarge volumes o[.,uoh [u"l makc lhese "ll("TTmtivcs ecunomically unlavorahle for bolh unils"l M.lt. Young Slation. Puh'"ri,cd orminonized coal rebllm, m combination with SOFA,
are lcohn;cally fcos;blc bllt will rc'l"ire exlensive capital, opernling and maimenance "o,ls for f"d grinding egu;pmonl and raeililies when ;nslalled and ol'ermed rorbOlh unil, "I M.R. Youn;: Slalion. Till" is**,b~TIkd** in dclail in Appendix AI.

F"eI elc"ning is 0 lechnique nonnally applied lo rednce Ihe sul[\lT or ash conlent 0[" fossil fuel prior to combuslion. No example" or ruel cleaning orNorlh Dakula**li~'IIite** or we,lem subbiluminoll.\ coal slnclly lorNO, emi."io"f> redllCiion wcre found in ;]v"ibblc technicallLtemlUtt_ This lcchmq,," is consirJered inrea"ible for NOx emissions conlrol ofM.It. ¥Olmg Slalion boikrs**~l** lh" presenl lime.

Bum' & Mellonn"ll .1_10 Minnknla Power f:oopeIalivc, Inc_NO, BACT Analysis Study BACTAnalysis for MRY Station Unit I NO, Emissions**High-~usi.** low-dusi. and tail-gas**varialion~** ofsdeclive calalytic reduclion 

### (SCR) lechnology have been applied on pulverized coal and cyclone boilers as a posl-combuslion type ofNO

### xemission C(Inlrol throughout the world and in**lh~** Unilcd States, excepl on uniL.s firing North Dakola lignile_ The severily ofcatalyst blinding and plllg!,,,,ge [rom pJrtieulale mailer and flue gas,,", emilled from**eyc1on~-fircd** boikr:s burning North Dakota lignite**precllld~s** the lechnical le.asibl1ily for :successful "pplicJlion ofsuch SCR technology On Ihc 

### EGU, .1 Ihc Millon R. Young Slalion. 'Illis i, de,cril.>ed in derail in Appendix A 

### I with supporting docum"ntalion in Appendix B.

'lbe resull.> ofStep 

### 2 orlhe

### No,. BACT Analy:sis for delermining Lhe lechnical feasibility of**rOlcnli~1 controllechnologi~s,**  including various "layered" combinations, are listed in**Tabl~s** 

### 3_5 and 

### 3-6.



### TABLE 

### 3-5 - Technically-Feasible Potential NOx Control Technologies for M.R. Young Station Cyclone Boiler.:;

In Permaneol, FolI_

Seal. S.rviee 00



# - Exisllog Coal_Fir.d Cyclone UlllilY Technically Fea.ihl. on M.R. Yonng Coolrol Teehnt>lo 

# '" Dollers? Slalioo Unill hoiler? Selecti**V~n~ ~n..caI"1**  ylic Yes!'1 Yo 

# §**R~duclion** SNCR)



# - ·Conv""lional Gas Reburn Yes' , Yes"';R uircsSOFAorASOFA Coal**R~bnm** Yes' , Yes"'; R ujres SOFA OrASOFA Fnej Lean Ga, Reburn Nn' , Yes" (wiorw/om SOFA orASOFA**Adv"nc~d** SOFA No'"] Yes'·'. Jncludes**r~locale<.lli** ilc ngvcnrpons**S~ a"'l~d**  OrA (basic SOrA Ye,'"] Yes'"] Combuslion 1m rovemenl' Yo, 

## y.,' ]; I ically included wilh se**aTil(~dOFA** Flue Gos Recirculalion Nol forNOx conlrol Yo,' ) (not ex eCled 10**r~duce** NOx furlh",) Fuel Swilch;" I**Dl~ndin** 

### Yo Yost', (not ex eCled 10**r~duce** NOx furlh",) S"" le,hTIl<ll1 f<ll.,b,hly dela,l. and Illc:rllrure Refe",n"", In**AI'pend'~** Afo, d,lalls. (I)

- All polenLi,1 ,ombinol;on, ofL<elmolos;es nOII;,IO(], Soc d,scu,,;un of"layered"' <cehnologi"". (2)

_ A"nmc, tiSe ofurea for =gcnl. Limil,d numberofaClive In'lOU

..ion, On**cyclo"e-fire~** bOllors b"ming ="l<,m ,ubbiluminous (l.e. Powder River aasln or rrlll co,I). (3)

- LimilCd numberof,Ol;v, COn""I;o",1 !%

...bum (CGR) in.tlilalions on cyelone.-fired Doller>bum;ng PR.ll c"l. (4)

_**~;mil"d** number ofuomon,lmllon. or ,oLivo inSfal]"'on. ofpulverlzed 0' m;trOm'.e<fcoal rebum cyclone-firod boil=- Oned,monstr.ll;on ofpulvorize<f ,,,,,I "bum;ng wilb PRB COllI "

.. he," perfo,,"",d on , eyolone-n"d Doile,. "0longer acl,vc. O"ly une 0<1;"" porrrunenL coal,cbum insLall"ionOLI cyclone-n,ed ho;l,r ,LIming ",>Iorn bilum,"ou5 ooal, n"""**bumin~** "",",em .ubbiluminou, coal orligni"'. (5)

- Only one .hon_lerm "'" d,,,,,,o,,,aL;on ofFtGR"'" on 0cyclon"fiTO(] boilerhuming coal with "I"'''''''d overfirc ,ir. (f,)

- No cyclone boil"'5 firing Nonh Da'Ola ligniLohave in",II'd ha,;c 0' .dv-dnc<d SOFA. SecAPJlond,x A. (7)

- Con.idered panofSOfA insl,tlaLion [o<coal hoilcn; wiLhoUl combu",i"" connols for**NO~** redLlo,lon. (8)

- No e"lIl'pl« o[L1singrec;""I,tod nllc**~05** on COlli_fired boile", forNO, 'rniss;"ns e""ITOI**w<-~o** found in ,,,,,il,hle 'echni",,1 1;lor,'urc. Zoro addilion,1 No" red"Ol;O" pOle"li'l "'peel<d from In15 lcohniquo .Ione [or MRY51OI;on Unil I 12. Polenlial NOxreduo,ion improvomeo, on MRY Un;l I 12considcIO" p,rro['"oilvo",rn"' SOFA_ (9)

- z.,,,, add;,i"",1 No" ,w""ion poleoli,1 c'pcoled from ,hi, ,cohmque (.""",Loh,,,g from lignile 10lignilclF'RB hlend, Of IOO%PRB) alono for MRY SIO,ion Unil 112.

MinnkolO PowerCooperolive, Inc. 3_]] Bum. & McDonnelln,\CT Andlysis for MRY Slalionllnill NOx Emi",iOIlS NOx BAC r AIlal}"i, Slnuy



### TABLE 3-6
- Technically Infeasible Potential NOx Control Technologies for M.R. Young Station Cyclone Boilers

Tn Perm"nCIlI, FIlIIS""I" Service on**EIi.'lin~ Cn"I-Fi~cd**  C)'dnne Vlili'y Tochnic"ll)' Fe"s;ble nn lI-I.R. Young Cnnlrol Tochm,lngl""**Iloil"r"~** Sl"lion Unit! hoilor'! Seleclive COLalylic RtdUCLioll No'"

- IJnrc,ulvaLle fOllling "nJ c"laly" (SCRl: convcllliunal (high d."ellVDlion proble,,'" ""1'CClod. See**d;.'ClL~,ion** uUSI); Low-du.l; Toil-gn, Yes'" I No I Yc,'" ofSeR fe",ibilily ForND Ii nile. EltCI,0-CalalyI1c OxidOlion No, ha, nol Leen domomlrdled fu]l-{;Colc nor (ECO"') 

### No roached c01JUlIerc;al availabililY lIE-SNCR (osi" ammonia) No' , No'''. 11., not beon dcmonst,med on eydono. ROlamix(ROFA'SNCR)**N"'~** No'''. H.s 1101 becn dcmunstmled on eycluno. R;oh RoagcnlllljecLion (RRI) No") No' J. Roql1ires oxygen-free fllmaoe CIlvirumne'lI, wilh ASOFA var ing air/fuel would illcre"se NUx emissions, rrm + SNCR ","h ASOFA No" NoL ", See foollloic alld feosibil;ly u;,cussiorJ. AdvanceJ ConveniiollOl Ga. RehuOJ (ACGR) + SNCR NO'" 

### No Bo, nol hccn uemonstTalou 011 c clone, CIlOIll.churn , SNrR No'"' Nu. 110' nOL bccn ucmoJl5IT"tod 011 c ·Jone. Fucll.oan Gos Rebum + SNCR Nu'" 

### N" Ib, norheell uemoll,<ITaled on cyclone. ROLaI;ng osed-F;rod A,r No'" 

### No. Jlos nol boon uemunSIJOied 011**cyclon~.** Oxygen E!ulOllood Combu,lion N""" No. ll" uorhoon dOIJlOn,"aled on c clune. Waler**Inj~clion** No""' No''"' hel Ck"n;nJ!. Not for NOx c"nlml No" I ' (nol ex ocleu to reduce NUx fllrlll",) Se, leohmoul**f~,~'I"llly** deL",l, ,ml 1,1,,",u,e j(dcrene,", '0 Aprend,x A fo,**~oLa,l,** (I)

_ All po"nli,,1 oombioaL;ons of[<chnolog;c, n"llisted, Sec oii,,",,-,ion nr"!oyer",l" lech"ologies, (2) -lim,i,-,I "llmbcr o[,c,;ve ,,,-,m!laLlon, on ey,lone_lired boiler, bmn;ng wesLcrn**s,,~h;,"llli"o",** cool. (J)

- No Idonl;li,d Lns",ll"io", "" ,,,.I_flredboile" no ,"e lJn;led Sidle>. One lall_coo SCR "" oyclono**bOlIc~** io C;",,,,,ny. (4)

_ S"" dLSous;iu" orSCR fcallb;I;ly Ii" ND Ilgnile '" App,,,dlx Al "n" App""li, R (5)

- Hy,J","", Ilon_enh""c<1 SNell h" nOL**~c'n** ,J,,,,onsrraLoo un " ,yclone-flred 00;1", no, an)' bOllcr Ii,;"g ",e.sLcm .lUbb;IUm;nU"' 0001 orlign;lc (6)

_ RotaLlng Oppo,ed_l'ired Air**w,,~** '" w;LI,ouL SNCR h" ""' bee" demon>Lr_Iod M 0ey,lone-firctl "nil,f. No "PP''''O' ';S",I;''''I ,dvanl"S" over SOFA on cyclnne_nrc<! boilcrs- (7)

- R1eh R'''g''"' Injeo';"n h< """0 'neeess[\llly**~o",n""ralCd** fOT brid**~"iods** wllh SO,;\. w;ll, and**wi'~o"l** SNCR aLTWO cyclonepoworplo,,1S- Thcrc "" n" po"".ne"1 RRI in'I"II.,iOLJS oompkl"d "nd operaL;o",1 "' o["May 2006, D;[fien!L;e<;n**m,;nt,,;nnl~** '0**o,y~'"1l_f,ee** rn,",o<: env;",n"'''''' '" MRY SI"I;un 

### [,,,,1,,, where the ",ea**Ica~cnL** wuvlrl he inject'" duo Lu eyclono "rll'el imh,l,ncc, <I",;nB alr_>L"TVcd 'omIHL<I,on would ;ne'''''''' NO:< em;,,;"",. (3)

_ No known "e""''''lmllOns UT l""'''",''"1 ;n",lla<ioo, "rAd"anced eon"enl;"n,,1 B" rebum (CGR) 01 fLGR'M or plllv,,;,cdlm;oTon;",J ooal rcbllm (PeR/meR) In oombi""I;"" w;lh SNCRoa eydone-nredbOllers CGR and I'LWmCR requiTe ocp"aLcd overn,c air. fLGR'M he> heo" arplLed Lo**plllvc~;"d** coal**f,nn~** "';10 a",j wiLhn", SOFA, w;LI, a"d w;Iho"l**~NCR;** FLGR'" wiLh SNCR;, ,Iso ""lI,d anl;n,-enl,a"ced fuel Jean g"**,e~,,,n** (AEFLGR'M). (9)

- Nu kmn,n demon>!"I;"'" or pcnuancn' ;"<I,,llol;on, ofo'YE,n-.o"I'aJleed comb",t;"o (OH;) on cyclone-ii,a! bol"". (10)

_ No**pem"In""II~** IIlsL,lIe" e'"nJ),Ie<**of",,"~** Ihi, Led'n;qu,**oo,"iouoLlsl~** On ""ai_fired oo;k" were fOlllld in av,il"blc le'''"kalli,«aL",e. NoL sui'able rm h;gh_mo;sture l;gn;Le fuels. (11)

- No kno"" demon,i""ion, orpc",,"oenL i",,,,lIaLlOn, ofL"i"S II"., L""h"<q\lo eonlinu"".<ly 00 oo,l-Ii",1 100,1", for NO. em;s.sion' ronLrol were fo"ml III 'Y:lil,blc ,c,h",,,,,1 IIlCTlILllTC, '7, 

## >. '> 

## ,<
• 

# •


# . '

Bum, & McDOIJlloll -1- 12 Mimkko", Power em'p",ali,,", Jne.NO" BACr

### Analysis Study BACT**A~.lysi,** 

### roc MRY 5,a,ionUnil I NOx**Em;.~,i"",**


### Addilional crileria besidcs**te~hnical** 

### feasibility 

### are ulili7.ed for tcchnology**sele~lion** 

### in a BACT 

### analysIS have been indudcd in Ihc following seclioIlS summarizing conlrol effectiveness estimalCS, capital plus openlling and mainlenance coSI**cSlim~lcs,** 

### energy imp_cIs, and environmental impacl.S:

• Conlrol effcCliveness (i.e_ percent pollulant removcd)

•**Exre~led** 

### emission ralc (scc Tables 3-7, 3-8) and cmission reduction (Ionspcryearj

• Economic impncls (Iolal cost and incremeLltal cost eiTcclivcness)

• Energy impacls

•**E~viro~m~ntal** 

### impacts (oilier mcdi" .nd**~missions** 

### ofloxic and ha:7.ardous air**pollut>onl~)**


### 3.3 RANK OF TECHNICALLY FEASIBLE NO

### x CONTROL OPTIONS BY EFFECTIVENESS The lhird Slep in**Ih~** 

### ''1op-<!ownn 

### BACT evalu"lion is to rank the remaining:**co~tmltechnolo~ies** 

### by effeclivencss. The**purpos~** 

### ofranking the control Icchnologies is to cslublish hierarchy thaI '»laces al lhe ''lop'' lhc conlrol lcclmology that achieves lhc IOWCSl**~mi""ion** 

### lcvel."

The

### ~;;'ission reduclion (oontrol elTcclivcncss) percenlages developed for mnking the "vailablc

## No,. emission conlrol oplinns considered feasible forMillon 

### R. YOllnl;**Sl~lion** 

### Unit 

### Iare shown 

### in Table 

### 3-7.

## ThCS~ ai'e estimales bas"d upon

## engi~eeringjudgmenls wilh considerations of,



## , • 'Boiler**h~al** 

### inputmles a,sociat"d with**r~a1islic** 

### uppcr boondary operaling assumptions;

•**bas~line ~mission**  

### rales correspondmg 10 

### the realislic upperboundary**np~1** 

### aling assllmpliun:;;

• lhe gencrJI combostion properties ofNorth Dakol:llignite;

•**I'ublish~d** 

### and availablc cmi.sion reduclion performance**achi~ved** 

### al**olh~r** 

### similar u,ility powerplanls (cyclone-fired boikTh);

•**compuler-d~..-ivcd** 

### prediclions; and

• inclusion ofperform.ncc margins 10 

### allow for variu!iens in**fn~],** 

### wealher, equipment condilion, and othcr factors lhat prevenl the ullimalc peak short-lerm performance from**h~ing** 

### reliably ,uslained over 

### Ih"**cours~** 

### oflong-Ierm**op~ralion.**


### These NOx 

### emis;ion level and reduction percenlage cs!imalcs include adjuslment. ofpreviously**lkmo~strated** 

### or predicled performanoe Ihnl**reI1~o(** 

### diffelenccs bClwem North DakoLa lignite "fill e"Slem
or midw",lcm bilumjl\OlL< and weslern subbiluminous coals.

Minnkola Power 

### Cooperative, Ino. 3-13 Bums & 

### McDmmdlBACT Amly,i., rOI MRY Slation Unil I NOx Emi,.,iull.' NOxBACT Analy'l' Sludy



### The**numb~n;** "ssume lhc cslimate{J capabiliIy orIhe cmployed lechniqJlC is achievable and**sJlslain~hlc** (Innl\-lc'r111) and Ih,,1 polentinl operalionHI limilation, menlooned in Ihc feasibilily disclL%iom allow the succe"r"l praclice orIhe ledmi'l"e or leehnology. None oflhe remaining conlrol oplio", 

### It"S bcen illslallcd on n GycJone-t'r("d boiler burnmg Norlh Dokol" lil,'llilc. As ,;nch, Ihe exrress<:d conlrol pcrcenlagcs reflect lho usc ofel\ginccringjmJ!,'ll1cl1l, bosed on the lislcd Icchniquc or lechnology Jlpplic"lion. Thi, 

### is pat1iculurly**periill~nllo** all control oplions Ihal involw alr-slagcd conlbustion associalc(] wilh variouo funns ohcpamled**o,'~rfire** aiL SO!'A-ba,cl!**~ontrol.,** for cyclone-Jire<1 <:oalburning boilers have typically reduced NOx cmi,,;ion levels sinni[ic"nlly from Ihe precontrol baseline, nnd whIch allow 

### or enhance furiher reduclions when combined wilh olhe, cuntrol tec1mi'l"c, and Ic<:hnologie,.


### 3.3,1 ESTABLISHING BASELINE**NO~** 

### EMiSSIONS FOR RANKING CONTROL OPTIONS Bcfore Ihe**V~nous** fea.,iblc 

### NO, emissiun**con~-ol** allemal;ves can be estimaled nod ranked in order of erfecllven<:ss, Ihe preconlrol baselinc level ot·cmisoioll.< and**i~** b.sis must be dClcTIllined. n,C EPA'a NSR Manual rrovidcs genelal guidance for c,IHbJishing eSlim.lCd b"selme CnUSSlOns 10 b<: used for Ihc purpose ofcalclilaling and comparing Ihe control and cosl_effeclivel\e&, ofa coolrol oplion: "The ba>elinc emo."i"ns rate rel'rc>enls a renlJ,lic scenario oful'rcr boundary unconnoned emissions from lhc ,ource_ Thc NSPSfNESHAP requiremellts or the 'I,plical,on ofcOlltruls, induding olhcr conlrols nc'Ccssary to comply Wilh ,%llc 

### or local air polMion regulutions, al'e nol considered in ca1culalmg Ihe basdinc emissions. 

### In othcrword." baselllle emi"ions ate e,"ellliall

### y llnconlroJlco cmissions, calculaled**usio~** rcalislic uPl'er bounda,y**0p~'n'l"'g** as.'LJmplions_ WlJcn calculating Ihe co'l efli:c(ivcnes3 ofa<1,bl posl-pIoCe" emi"ioll" conlrols 10 cenain ;nherenHy lower polluling processes, hnsclio<· emis.sions may he "",umed to bc lhe emi,sions from Ihe lower 110Illllmg proce" il\clf. 

### In olher wortls, em",iun Ieducliun credil can he laken for Ihe use 

### 01'mhcrcnily lowel' polluling r"'<:Gsses''''.

Also "Ialed in Ihe EPA's NSR Manual: "E,timaling- reali'tic upper bound case scenario <1oes not me'n Ih"llhe sourcc operales in an absolule wor'l_cose manner ail Ihe lime. For**c~ample.** in dcveloping Jl rC"lislic uppcr buundary casc, baseline emissions calculalions can also consider inhcft-nl physieul or orem1iom,I "onsb-ainls on lhe "OllrCC. Such con'lr.inls should ac<:mately reflect the true
"IbId, NSIl Man",l B.37
3-14 Minnkora Pow", Cool'omlivc, loc.NOx BACT All,lysis Shldy IJAC1.· Analy,is for MRY StationUnit I NO" Em;ssions



# ,**~,** upperboundary ofthc sourcc's 3bility to physically operate alld the upplioant should submit documentation to verilY these constraints""'.
Establishing estimated baseline NOx emissions for a new or existing; sOurCC involvcs detcnnining the desib'll or operation"l b"is ofthe emission rate. A ugcful meanS ofcomparing such emission rales is to cstablish the unit emission rate, expressed in pounds ofpollutant per UT1it o[process oUlput Forprocesses such as Slcam·electric gcnerating powclpbnts utilizing comlmstion in boilers, the desiled prooess output (kilowalls or mcg"waUs) can be related to the**pollu~,nt-bearing** nue gas eleatc<! by Ihe combustion of fueL Units offuel heat input (millions orBnl.,) required to create a Ullil ofdcslTOO electrical outpul (kW) and thus the efficiency ofc:onverting the fuel heat to suoh eleotrical oulpU! (unit heot ralc, BtulkW-hr) are irnportanL

A review ofreported hourly NOx emissions for MRY Station Unit 1 boiler, including uni! maSS rales (lhlmmBtu and lblhr), boiler heal inpul (mmBtulhr), and gross electrical OUlpul in**mcg~w'dUS** (MW

## J, "IuS

,**p~Tform"d** for Ihe operatiog periods in years 2001-2005 inclusive. A rcali"lic upper bound emission case

. ieCll"rio for eoch boiler's lxtselinc cmissions "I Milton R. Young Station detennined the highest

"ummalion ofany rolling 12·month period NO" muSS emissions (pounds), along with the ,mmma,ion of '[he glOSS heat input (mmBtus) and Ihe boiler opef3ling hours 

### for thc some rolling] 2-monlh pcriou 'corresponding 10 lhe highest NO:< pounds. Dividing the summation ofthe rolling I2-monlh NOx pounds by he.t inpll! resolL, in a average unil emissionratcs (lbfmmBtu). Likewise, the summalion orthe rolling 12-monlh grOS" heal inpul (mmBtus) divided by the boiler operaling hoUls yields an**u~cmgc** gross heul input ",te (mmBtulhr). 'This emission evaluation levC"Jled that;

• Unit I al Millon R. Young Station is l}'pically operated in a base-loaded manner;

• MRYS Unit 

### I 's highest 12-monlh NO" m".,; emissions summalion divided by the summation of the same 12-monlh period's he'dt input avelJged O.8491blnunBtu at 'd eorre'l'onding avernge unit heal input rate of2,744 mmBtufhr and unit gross electrioal oulput of244.5 MW•.


### 3.3.2 ESTIMATING CONTROL-EFFECTIVENESS OF NO. EMISSIONS CONTROL OPTIONS The degree o[success in operalion ofseparated overfire air alone "nu in combi""lion with Ihe other Selecled feasible**ahemali~es** is imporlanllo Ihe amount ofNOx cmission reduction achieved. The emission oon(rol perforrmmee [rom the advanced version ofsep"ratcd ovedirc air (ASOFA) is highly
"Ibid, NSR Manual B.37
Minnko!a Power**Cnnp<ra~vo,** Tno. J-15 Burn, & MoDonnellNOx BACrAtllIly>i> Stlldy
dependent on lhe degree ofsucc"" in admitting combuslion air**inBu[ficl~.,,1** for complete combu,l;on in Ihe cyclones wilhoul caming relaled negalive impacL,. Tbc eunlrol percenlage, es!imn(ed tor 

### fi, mg North Dakola Iil\nile in the 

### MilY Sialion boiler.' reflect Ihe belidth"l ope' atm!,: Ibe c"i,lmg cyclone, mucb below "n "vCrJgc cyclone ,Ioichlomelric 

### ,;,110 ufupproximately 

### 0.95 (95% 

# or !hc lhc<Jrcli",,1 "mOLlIlI ot· comboslion air required for complelc combustion) will nul be succee.sful. Thi, IS due pnmarily to Ihc c"p"clcd ",Imv"d ui," combu."ioll causirl).';" rcdtlclion in cyclone f"mace gas le,nper.l(urc", IIHl' clearing
a Sllong poten!ial for**molt~"ll** sIal; solidifying III Ihe cyclone harrel" slug; I"p', and lower [umaee Iloor ope"ing". TIlis would impose a grcat ,merruption 10 slcam pTOduclion since forced oUlages would be fl'quircd 10 Te'rlOVe 'hi" physical ObS""llCliOn helore full load boiler ope' allOn could he ree'lahli"hed. The lc!'A's dmfi NSR Manual SI"I"" "It i.' llol the "EPA's intenlion to reqlliTe nnaly"i, nfouch pOS>lbk Jewl of efficiency [or a conlwl tcchni'l"e, as "uch un al1lllysis would ,esull in a IUTge numb", ofoplions''''.

Thc polenlinl operationallimi(alions [or deeply alr-slaged**eyc1on~s** a"ocialed wilh separated o"erll,e air and Go"l**r~bum** alIemati"e, are expected to Iimil the amounl ofNOx conti01 pntenlial possible from "ucces"[ul rractlcc o[Ihe parliculn, lCehni'luc or 1<-chnoloID'. TillS i, 'lcscrib<xl in Ihe ,klmle,1 ["",ibilily**~i.,eussio,,-,** inclnded in Appendi" iU.

The**a,lv'Jl1"e~** form of.,eparaIed overlire oir is expecled 10 be effccllve in NO

### x emi'sion re<1ucliorl alld

can be combmcd wilh olher fensible**c"mbu,lion-rdole~** and po.<t--combu,lion conlrol**"li~TIlativc~** [or**Ihes~** lip;ni 1e_lired cyclone boilers. The basic form o[SUFA in combinallon with coal rehum, ga" 'ebnm opliuns, and SNCR, was not included in lhe delailed conlrol cf[ccliveness analy",s ill order 10 limit Ihe number o[ oplions lhat were evalua(ed.
n,ing an advonced Conn o[SOFA 'yslcm, M,lt. Young SlnlinJl's Unit 

### I', boiler operJling al 

### MeR i"**e~pecled** 10 achieve a NOx emission level 0[0.51 IblmmBlu when operating modeslly ail-"(aged cyclone fumaees with ,ull;,b1c eomb"slion COJllTOls. This level ofNOx reduclion Ii-om ASOFA opcr"tion, approximatcly [orly**pcrccn~** IS based on Ihe**~~pecled** ahiliry 10 reducc cm""ion, witboul incurring pOlential sigmficanl negalive ;mp"cts o[Ihis tcchnique_ This reduction estimale inclndes Ihe addilional amonnts ofconlwl pOlential "vailnble fTOm operaling with relocated lignile drying 'ysl',u**v~."t** ports nssociated wilb ASOFA opcr"lion wilh modcstly "ir-staged cyclooe [umac"". - 

# ...

Dums & McDonnell ]-16 MinnknLa Power Cooperative, Inc.NO" BACfAnalysis Smdy BALI ADaly,is for MRY Slalion IInitl NOx Eml."iom



# ------

!f. 

# " Coal reburn with ASOFA is estimated toreducc 

### NOx emi:;..,ions for M.R. Voung Station'sUnit 

### I's boiler opcrating at MCR slightly less lhan 

### 55 perecm from the pre--conlrul baseline NO" emission rate, cOLlsidering similar control levels demonsualed by previou, coal_reburn re!Tolits on cyclone-fired boilers and limitations previously discussed with ASOF

### A.

Cunvcntionul Gas Reb"m and Fucl Le;rn G'H; Reburn oplions were both assumed 10 be instaned with ASOFA. NO" reduction from CGR with ASOFA operalion is expecled to 

### be approximately 

### fifty six percent. l'LGR with ASOFA is expecled to reduce NO" cmissions approxim"tcly forty six percent Es,imales 10' NOx emission" 

### for M.R. Youog Stalion's Unit 1'5 boiler considered similar c:onlrollevels dcmonslrated by previous gos-rebum reu-olils On cyclone-fired boiler:; wilh modesHy air_st.aged cyclone furnaces "mllimilalionspreviously clisc"'scd wilh ASOF

### A.

The NOxemission rule for**Selec~ve** Non-Calalytic Reduclion (SNCR) (nsing urea) wiLh ASOFA 

### is expected to be approximately 0.J55 I 0.3J, re.,uHing from a reduction in NO" emi

..ions ofapproximately 58 percent from lhe 12-monlh avemge prc-eontrol baseline NOx emission rale.

Included in the feasible con!Tol oplion ranking ofTable 

### 3-7 are layered allcrnalives lhal were shown in Tahle 3_5. The highest-perfonning NO" control**altema~ves** remaining in consideralion are ranked in declining: order ofexpec(ed emission reduction. These combined conlrol oplions re["er 10 "adv;meed" SOFA, which is c)[pcclc"{] 10 huve significantly I01,VcrNOx emissions lhan" lypical SOFA "yslem as applied 10 the MiHon 

### R. Young cyclone boilers.

MinnkOIO Power Cooperarive. Inc. 

## J-n Bum' & McDonndlHACT Analysis Ii,rMRY SlallUn Unit I NOx Emi"ion, NOx BACT Analysis SnLdy

------------ 

### TABLE 3-7 - Ranked NOx Control Options Feasible for MRY Station Unit 1 Boiler with Expected Control Performance

(I) AI' "oIOWC5<\"" 0, ml (2)

_Con1rol pereenLages are relaLive Lo an**a\'IT1l~C** prc_oolltrol cmJSSlon baseline 0[0,849 Iblm",mu ],,,,,.1 on annulli opcr"ion "L h,gl,e" IHc_control 12_mooril ,oiling NOx so"""a'i"" ,,"'"**em,~,io",** drvlded by 'he 12-mo"'" he"L mpuL ,u",maliOLl. All. ROl;s,ion llal. Conlrol Lab'l'" NO, Conlrol T<chni( ue (lblmOlBlnl**Pore~nla** c") 

# , SNCR (usjng 11ITa) 

### wi ASOFA IU55 58.1 

# " Go< Rehum wilh ASOFA 0.]74 56.0

- - ---- - - -- . C LIgnilo Rcbum wi ASOFA 0,3B5**5~.1l**

---- 

# " Fuel Lean Gas T!ehnrn wilh ASOFA 0.460 4').9

- ..

# __. -- 

# , Advaneeu SCp"Talc<! O\'edlTe AlT (ASOFA) 0.513 395

--- - - _. _. - - ._--

- lJaseliue 0.R49

- em,,,i,,,, ,b",,,,'i,,n "-,,ic'",,1 fmm In**'h,~** 

## , 

# " ,-**.~""n** ,are.

Thc annual e",i",ion levels dcveloped lor T"bk 3-7's ranking lhe feasible allernalives assume IhJL Ihe highest 12-monlh "vm'f\c prc-rclrofillcvcJ ofunil 

### NOx emissium fur

### M.R. Young Slation's Unil 

### 1',**~.~-""** hoiler J< a baseline of0.849 Ib/mmTIm. TIli< wa, delermined from Ihe highe,l Toporte,1 rolling 12**con~,'CuIive** momh period's .,ummaLion onourly 

### NO

### x emissions (Ibs).

The hourly "'TOSS fuel he«l inpllt (mmBtu) was summed over llml same 12-momh lJme pr:riud, ;md ,lividcd by lhe numbcr ofboilcr upcralmg hours 10 yIeld an annual JVeT"gc**~""** fuel ],eaL inpul wlc (mmBllllhr). Mullil'lying lhe 12-mo011h avel age heat illpUL rate (mmBtu/hr) by the baoclinc ur contwl ahemallve's 12- munlh avcrngc u"it emi.<sion rnle (lblm",)3lu) c'lu"ls " 11-rnunlh avemge hourly NUx emi<..,iom rnte (lb/hr), Annuol 

### NOx emissions (LOns) ror lhc ba,elinepn'-cunlml cn"d,lion were cJlculated 

### hy multiplying lhc J2-monlh sumrnallon for boiler operaling honrs durin!; lhe ,,",me perind as lhc hIghest 

### NOx cmi"ians by Ihe 12-monlh**UV"""g~** cmi,sionmtc (lblhr). The annual Ions for lhe conLml oplions
were ealcubkd by m[J]Liplying Ihc allomulivc's "vmrgc 

### "nnm,1 "",is'ion raIe (llJl)'Tl hy 

### arednclion**f~clor** (i t·2wilc"hle) for heal il1pnl or running plant capaclty and adjoslin!; l>oileT opcrol;ng hours by an annual uplime (availabilily) fucior. nOlai],; for**Lhe,~** udjuslmenl> aTc includc-d io Appendix CJ. Ba,ed un Ihosc calculations, lhc annw,] cmissiofi> far 

### M.R. Youn!; Station's Unit 1

### 's boiler are shown io 

### Tnble 3-8.

nun" & McD"nudl M;Illll<Ola PuwerC""peraoIV', Inc.NOx BACfAnalysis Sludy BACfAnalysis for MRY Slaliuu Uni, I NOx Emissinns



### 3.4 NOx CONTROLS ANALYSIS AND IMPACTS EVALUATION The fourth slep ofa '1op-<lown" BACT review is to evaluate the mosteffeClive emission controls.**En~w,** ccunomic, nnd environmenIal impnGls arc 

### 10 bc con,idcrcd in the Gontrol technology evaluation. The purpose ofthe evahmlion is to determine ifthere are any energy, ecunomic 

### or environmenl"l impacts thalwould eliminale lhe top control tcchnologies from consideralion.



### 3.4.1 NO

### x CONTROL ECONOMIC IMPACTS FOR MRY STATION UNIT 1 An cvalu"tion was pcrformffi. 

### to delennine thc varioug COgt impactg ofinsLalling f""siblc 

### NOx control alLematives on Millon R. Young Unil 

### I. This evaluation includcs cslimaled:

• Capital costs;

• Fixed and variable operating and mainlcrmncc eosts; aod

• Levelized lolal annual eosts 10 engineer, prooure, construct, inslall, startup, teSI, and plaoe into Gommcrciul operation lhe parlicular eomrol technology. The re.,ull" ofthis evalu"lion are summari'.ed in Tables 3-9 through 3-13.



### 3.4.1.1 CAPITAL COST ESTIMATES FOR NO

### x CONTROL ALTERNATIVES The capiLaI cosls 

### 10 implement lhe various 

### NOx cOIltrollcchnologies were largely eSlimaled from unil oUlput capilal cosl faGtors 

### ($IkW) published in technical papers discussing those oontrullcchnologles. Tn the cases ofSNCR. preliminary wmTor budgelary cost informalion was oblaioed and used in place of, or to adjusl, lhe published unil outpul cosl faclors. Thcse coal e.,timales were eonsiderffi. to be sludy gm<!e, which is 

### + or -- 

### 30% aeeuraoy_

The unit nameplate output cnpaeity (gross electrical output in megawatts) assumed for thc 

### NOx oonl.-ol lL"Chnologies capilal oosl eslimatc basis was 257 MW. for MRY Station Unil I".

A review oflhe 1mil**C"pil~l** WSI factor range and single poinl fnctors applicable 

### 10 MRY Station Unit 

### 1 NOx eonlrolleehnoJogie, are presented 

### in Table 

### 3-9. The estimaled inslalled and levelized capital coats for the highest-performing form 

### 0Lthe various feasible 

### NOxemission reduolion technologies evalu"lCd for cool-cfIceliv"Tless are 'hoWll in Table 3.] O. Thc,c are 1isled in order ofconlrol elfeclivcness, wilh the highe.,t mnked oplion allhc lOp.

"" Ibid [0001010 number 23.
Minnkol:l Power Cuuper.l;"•• lllC. 3-20 

### Bums & McDonnollIJACT Allaly,j, fur MRY SL:l,ion UniL I**NO~** Emissions NOx BACT AIl'lysis Siudy


### TABLE 3-9
- Unit Capital Cost Factors of Feasible NOx Control Options for MRY Station Unil1 Single Po;,,( lJni! C"pi'al**COl"~** Fac(o,"', AU.**R~ngel1l** ($lkW)**La~<J'"** NO, Con(rol Tc<ln,i 

# "" (SlkW) MJl.YS Unit J



# " SNell.**(u,in~** meo) 

### wi ASOI'A 20-.15'" .11.fo"').'"

.---. 0 Go, Reb\lI11 wi ASOFA 15-)0,0) 

### 70.1"""""**~.** C Lignioe Reb"", wi ASOFA .10_(,0'0) 1g1.51'"''

... - 0 Fuel Le"n Gas Rcbum wi ASOF/\**~~** ('" 41.4"'-""01 ---'" A**/\d~al1ced** SepMaled Overfire Air (ASOfA) 5-101 ') 

### 16.d" (I) AlLem",ve**d,,,~nAlIon** h,,, Pc( n .""gnc" from hlghes' '0 low'." u",I)\O,**em'~""n** r_'e. (2) II,,,, q,P""! eo" f,etor:s (YkW) onhe.'" ""h,-,<lo,1**kch"olo~ic~** combined by**"m~le** ,ddllion MtIl,1 ,,,,,,,11,,1 "0'" nlOY <liffor LhlS due '0 r",;';ve ,n ",'gaLlv,**'yne,~;,,;e** effec" I(,ngo 0"-,00 0"**pn~I"h'~** valu," or v,",dor [''''ro,.I," (J)

- Smglc po;," co"' (;"Ior is be,' ",1;m"lc [OfdeLorminaLio" ofLo"l**m~"101** coS! foe" PdTlicul"**l,,"hn"lo~y** or cOIllO;"allOn,**"-"nm;n~** m"imllm nnit capoclly " ooscd on EPA", "",""pia'" ,,"ng, Single pomL eosL ligure, in 2006**doll",~** (4)

.. r",;",,"OO capilOl coS! for**~NCIt** rO'"L """,,,Je ami rLGR pOlO' c,"mOlc demed from December 211114 budgeL"" prop"sol hy foci Tech. Sec Appendi, C2 for d"aik (5)· 'Ille**<;n~le** POIn' uoi, copHal eo" foe,oT shown for LI," ",,,Iv,"e,'(]"" vc"ion ofSOFA derived from Bums & Mdl"nTwH inle",.1 daLabase ,nd cost «LunaLe "" NrnLl, J)ak,,," l,gniLc.IiTed cyclone bo,I,,, (6)

- NESCAIIM**20~"\** Techm,,,1 Paper. p""ed ,,' Lheir web.lL," See leclm;,.1 ,e['<enc" m Append" AI rOT**dcL"il~** (7) TI"**.',"~Ie** po,"L "niL e,piLoI cos, foeLor ,ho"n I,,, a eonv'"O';"",1**~"** "bum sys<cm ,"c1udes the e",maLed**,,,~i",1** eo" 10 ,",1,,11 " high**~,e"",e** "a'm,,1 g" 'ul'ply I"pelino (J I,4 >!kW), and II", bOLh bo,I,", ,I,are the "'1',"1 co,, rn pr0J>O"l0ll '0 ,hc" ,0.'I'"""v<

## r",oo MW gro50 ",Ilp," cop,ei'ic,. (8) Th<**"n~'"** poiOL umL capirol coS! CacLo, ,bow" lilt ,**li~ni<c** ,eb"m S)'S'em " highly ,"e_speeific, ond**'~I"',"",** Ih" new p,II""i,,,, anJ**h",IJ",~** e"dos,,,,"f" rcqllired, The geoe,,1 co.«**'d"~e** f", pulv"i,,,1**,",I-[iTC~** b"ilers 1S InCluded 'n ,he NESClo,llM 2005 Technic,1 P'per: [or cyclone bOil",,;, inclH"c'(] io ,he 2005 WRAP DralL Repon, p:>.lled" ,he;, \I'd",," Th," ,i"gle porn' ULlH mpllal

# co" CaeLor lor 'h;> ,I""m,,,,,c fOT ,"c",,,sed PM eoHcc"on e'paCJly i"c1ud," io**II~,,;'e** ,,"bum opllon is**~L** 7 $lkW.**~ee** "d"","1 ",ferenc" i" AppendIX AI for del,il,. (9)

- The unll "'1""'1 e,,,' f"do'**Ta"~C** fOT fLGR ,pplicollon, on ho,le" w;'h"u' ""**",;"io~** "**h;~h-p""u,o** naL"ral R'" '>"I'I,ly Wa.1 no' f<lll"" 1Il "vailable Lcchnical li'eraL",e 11,.,**';,,~Ic** ....'n' lmi, C'pH'! C(';( Cacom shown for a C",I Icon );'" reb"m 'Y"eon includes 'he e«;maLed ""p;Lal

# co" '0 in",,11 ,**h,~h-prc"ure** o","ml gos .uWly r'pcl,"e (15.7 $I"W), ,nd 'hot bo,h lH.oilc" sh"" the eap''''1 eO.1l ;n rmpm';on ", ,he;T r"peel've raLcd MW gfOSS ou'puL "'I'"ci",".

IllU'L' & McDonnell
.**~_21** M"mkolu PowC''-**(:oopordll"~'** Illc

.**NO~** BACfAnalysis Sludy llACf An.ly,is for MRY Sl.lion Unil I NOx Eltllssions



### TABLE 

### 3-10

- Estimaled Capital Costs for NO. Control Alternatives
- MRY Station Unit 1

Iml.lled**Anllu~[Iz.d** Capil.1 Capilal AU. NO" Conlml AU.rnaliv. Cos,flI COSl'" L.bel'" SI,OOO SI,OOU 

# , SNCR wi ASOFA 8,l1J 

# '" D Gas Rebu," wi ASOFA(') 18,006 1,570 

### , C Lignilo Robum wIASOFA'" 46,656 4,068 B fuel Le.n Gas Rebum wi ASOFA1 ') 10,639 

# "" A Advanced SOFA (ASOFA) 4,277 

## m llaseline 0 0 (I)

_Allen",I1V< label h" been**=l~ncd** from hlghcSl 10 lowe>l 

# U"" NOx <m">IOn nllo. (2) • 1",,,,llod ""piral co,l i, <>iim,loo [ordolmnin,lion ofloral car,"l <,,<1 [ora parI;oular 'e'llnoloBY Or eombm,uotl, assuming 2S, MWg uni, cal"'ci'y fiLmg. All "",I r,gllTC> in 2006 doll"", (3) • Allouali?<d ""pi'al eo,1 In,i,llcd ClOpilal co," , O.Oll7l**an"ual;,~d** car,L,1 00" facmL (4)

- Co'" [orgo> robum opLioos include hiSh_p,,",uJe nal

..",1 gos**,up~ly** plpclinc in"",llcd capH,1 CO>l ,f**~S,07S,OOO** for CGR '0" $'1,0.13,000 fo, FLGR; and ,"nual,zcd capiLaI co," of$71M,OOOlyr fOT CGR and $J52,000 ro, Fl.-GR- Sec [""'nol",, #8 .no 10 undcrTobie J_9. (5)

_Co,sLs for i"crea,ed PM ""lle<lion**,",~<;ly** inch<doo in lJgoHe 

## "b"", op,ioo ore S2J,56l ,UUO for LruLalled ""p,'al co,", ,nd**~2,054.000lyr** annualized capiLaI co,'-



### '3:4.1.2 Operating and Maintenance Cost Estimates for MRY Sta1ion**NO~** 

### Controls 'The oper;uion.l amI maintenance cosls 10 implement the vario,," NO" conlroltcchnologies were largely estimated from COSI u,clors (percenlages ofinslalled capi!;}l co,!>;) c,lablishC<J in lhc EPA's AirPollution ConlTol CO,1 Man"a] (OAQPS) for SNCR", alld from publi,hed in lechnical papers discussing thosc controllcchnologies. In lhe oases induding various forms ofSNCR, preliminary vendorquoles WCre oblUincd and used in plaoe of, Or 10 adjusllhe OAQPS cosl factors_ These COSI eslimates were considered [0 be study grade, which is 

### + Or·· 30% uccuwcy.

Fixcd amI vari"ble operaling and mamtenance CO.'13 considered and included in each NOx conlrol lechnology's**annu~J** O&M GOSlS ure eslimales of:

• Auxiliary eleclrical power consumplion fur operaling lhe addilional cOnLrol equipmeni;

• Reagenl**con~umplion.** and reagenl unil COSI for SNCR**"ll~TImlivcs;** and

• Reagenl dilution walerconsumpliun und unil cost for SNCR oHemalives.

?) EPA Office ofAll Qualily Planning m,d Slandards (OIlQPS) pUblicalion EP**A!~52fB·02·00** I, Seclion 4.2, NOx Controls

- NO, Posl-Combu.tion, Choptcr I

_Sdeclivo Non-CalJlylic Reduclion, d.lecl Oelober 2000, po,led at**l~eir** website: hllp:/Iwww.cpa.govlllnle.toluiTile>4_2**e~** l.pdf
Minokoln Powor C""'pem'ive, Inc. 3_22 Dums & McDonnell!JACTAnalysi., LorMRY Sla,inn Unit 1 NOx Emi"ion, NOx BACT An,lysis Sn1dy

• lru.-n.;1Se$ orsavings ill alL"iliary ek<:",call'ower cO"-'umpliun lor chan£cs in cool**prcp~ralion** equipmenl and loading,**prim~rily** for 

### fuel reburn cm,!,;l,;

• Gcneral operaling lahor, pillS mainlenanee labor aod lI1<Ilcrials devote<J 10 lbe addilional eillission control cquipmenl and ii, impact nn exi,ling boilerequipment.

• Rc,luelions In rev!,:nue expected 10 res"ll limn los, ofunil a\'",lablllly, i.e, onlage,,- allribut,obk: 10 Ihe conlrol option, which reduce annunl nel electrical genemtion aV<lilablc [or sale (revenue).

for economi" evaluallon pUlpo,es, an anumll "verage runlling planl oupacity faolor of%.6 perc"nl compared 10 a nominal unit output eal,acity of253 MW, combined will, nn overage nnnual oV<lilability (uplimc) IlfS,52H opm,ling hours (91.3 porcellt of8760 hOI"'; pel' yeor) resultulg in an "nnual ullil capacity [""lor**ot'9~.I%** wc!" a<3mncd for Unil I's pre-control hasel;ne mmu"loporation. A henl inplli rale 0[2,744 mmBlu/hr anu" NO" emlssion**r~IC** of0_849 Ib/mmBlU were assumcu [or calcllialing conlrul and cosl..,**ffcclivcn~s** Irom prC_oonlnll11UlXimurn ",l1illl\ 12 moolh**~um",alion** ofnilrogen oxides' mass cmi"ion' ror MRY SlatlOTllJllit L

Tahle J-Il show the et;limalcd anllual Ilremlinl; and mailltenance cosls "nd levelized "nnual O&M cosl vailles for lhe hJghest-pcr[orrning furrn o[ 11,e various fGHsible NOx emission H'<lLJClion t",·hnO]Ol;ic&. Tlle,e are il'lcd m order ofconlrol effeclivcnc,s, willl Ihe hlghcst mnked optlOn,"t**Ih~** mI'. The cost methodology summarized In Appendix C3 provide, more deL'lIls [or Iho levelJzed onnual O&M cos, ""leulnlions and <usl [1,eIO,.".



### TABLE 3-11- Estimated O&M Costs ror NOx Control Alternatives
- MRY Station Unit 1
A"n".' Lc\'cli,O<! Annual All. O&M CO\I'" O&M Co'l'" Lobol'" NO, Conlrol AHem.livo SI,OOO $I,OUU C SNCR wi ASOFA 5,417 6,764 D {i

.., Rcuwn wi ASOFA**2~,641** 35,765 C Lignil< H.ebum wi ASOfA 5,362 7,320 

### n FUjRwi ASOFA 12,86.1 16,062 A Adv.need SOFA (ASOfA) 1,695 2.117 Baschnc 

# " " 

# , _Aile 

## " I I,,, bo, ','"edf,o","i h

.. '0 low," u";1 N n ,al". ( ) m,""" I I:>c n "'" g <;>1 0, cm",," (2)

. Ann"al "p""I",g andm"in""'"O< co>! fu' pMlCU lar l<Cloloklgy orwmomaliOLl '5 comp,",d '0 ""il O,L'c\U'O o»Crolion01 

## ,n """gc """ on'p"' (244.5**MW~)** and 

## "",n"e<a01.J%**av,r.~,** "",,",1 "",ll"bilily, which i,**h;~h"-'I** "'''£ocUli"" 12_mOlllh, or"I",,"on em", 20111-1005, All e,'" figure, i" 200r, dollaLs. (3)

- Level",," anllu,l O&M co>' AIl"u,1 O&M coS!, 1.2,87] ,nnu,h,",1**Q&~l** 00" rac,",


## nnm, & M<llonnell 3-2.1 Minnkula Powe,-**C"up"r"llv~,** Inc,

# ! I 

# ,



# , , 

## , 

## I 

# , j 

## I 

## j 

# j I 

# , , 

# , , 

# ,**-~** 

# , 

# ,

• • > 0 

## • 

# , > 

# " • 

# , •



# " > 

# " 

# • 

# , • • • • I 

# , < 

# ,

, 

# ! I 

# " s 

# • 

# • • • • 

# " •



# , • w



## , 

# • • 

# , • 

# , j 

# i ;> 

### i'i 

# , , • > , 

# , • • • • • 

# ,NOxBAcrAnalysis Study**----~~-~--** !lACrAnalysis forMRY Sr.lIionUnill NOxEmis,ions



### 3.4.1.3



## ,,'



# , ,; (4)

_COSI' ro, increased PM collection ""I"',ily incl"d," in lignile r<b"m nl'Lio. are**~2,024,OOO1)T** for ann",1 O&M '0'1, a.d S2,S27,OOOlyr aonu,lj""d O&M coSl.



### LEVELIZED TOTAL ANNUAL COST ESTIMATES FOR MRY STATION 

### NO

### x CONTROLS In order 10 comrare a particularNO

### x emission reduclion allemnlivc during the inilial engineering annlysis portion ofIhc BACT scleclion rmcess, lhe sum ofeslimaled annualiud inslalled capital plus kvdized annual operating and maintenance cosls, which is referred 

### to as "Leveli7.ed Total Aonual**Cosl~** (LTAC) ofexpecled rollulant removal by implemenling Lhal**~ll"malive** was**ealculal~d.** nte LTAC lor aU NOx conlrol**allcrrwtiv~s** WtlS calculated based on the "arne economic condilioIlS and a 

### 20 yc-Jrprojecllife (see APPc"Tldix 

### CI formelhodology). The unil contml cnstwas then delennined as the 

### LTAC divided by annualloIlS ofpollulunl emissions that wouldbe avoided by implementarion oflhe respeclive alternative. The control**ahema~ves** were also compared by culeulnling thc**ch~nge** in unil cosl (incremenLaI OOSl) per incremenlallon removed for Lhe next mosl stringenl allcTI1"live. This idcnrified which alternalives produoed lhe highesl incremenl ofexpecled pollutanl reduclion for the c,timnlCd loweslavemgc unnu"1 cost**inercm~"IIt** cumpared Wilh the ba.<elinc emission ",te. The expected annual numberofIons of pollUlanl removed versus eslimatcd 

### LTAC for each remaining conlrol allernalive was lhen ploned.

Thc**comp~rison** of[he oost--elfect;veness ofthe remaining NOx emission reducl;em K-chnologics was made and is shown in**T~ble** 3-12 and Figurcs 3-1 and 3_2 

### for 

### MRY Slalion Unil I. These figures plOI eslimaled annual "mOlmt ofNOx removal (emission reduelion) in tons per year on Lhe ordinate (horizonlal axis) and Lhe eslimaled leveJized lowl annuul coSI in lhousunds ofUS. dollars peryearOn lhe .bseissa (vertieal axis), 

### for each ofthe remaining NO

### x control technologic'S. Points em thc gruph lhal are f;trlhcslto lhc righl and do.<esllo lhe hori7.ilnlal axis are deemed more cost-effeelive, since they represent controls lhal**achiev~** more NOx removal per dollarrequired for lolal annual cosls ofoperalion, mainlenance, and capilal recovery (depreciation).
Although the NSR Manuul rcpcale<1ly prescribes.following a "lOp down" analysis approach for BACT deleITIlinnlion, lhe developmenl ofa leasl co.,lenvelope wilh dominant controls**(~s** SeC"Tl in NSR Manual Figure B-1,**pJ~C** B.42) cle:lrly labels poinlS wilh lower emissions reduclions and lolal Jnnual cosiS lirsl. i.e. "A", '·U", elc. Lhen procccding wilh labding and connecting poinl' ploUed LUriher away from Ihe zero emission rcd"clion poinL This "bonom,up" approach is for plotling the leJSl--cosl (dominant) control
curve. The**bbelin~** ofeuch unit's NOx oontrol lechniquc allernative 

### ha., followed lhis approach.

Minnkola Power Coop."'Live, Inc. 3-24 llmn, & McDonndlDAcrAnaly,is lor MRY Sla,ion Unil 1 NOx Emi"ion' NUx BACT Anoly,'i' Smdy


### TABLE 3-12

_ Estirnaled Anllual Emissiolls and levelized Tolal Annual Cos! for NOx Canlml Alternatives - MRY Station Unit 1

( ) (2)

. EsLim'"cd ann",1 omission 'OJLI**"-~'",""** "n ann,,,1 c'l",i'y [."OTsjl<elfie Lo <,oil OILem,""" 94.1% wss a"",,,,,d [or Lhe oo.«I,,'e '""'. (3)

- EsLHT,"'<d annual LOO' ofrm,s<Lon "du<',"" ;, Lhe ,Iiffo'on"e**1>,,~·lO'"** ,nnuo! bss,linlO Lon, 'nd <alOh ol"",,'i,·e.' "nn"a! ,miSSlon, ([om). (4)

_u-vcli",d To,,1 Ann",1 CO" = 1Innu,I1700 1","'II'd 01,;1;,1 'W;L + LcvdizlOd A"n",1**O&~l** cost. Sec no'e**~J** I", Iobles 3_10 ood ]·11 for a"<\",I,,,," <c"L foe'''''' Emi»lOn,",c calcubLoo from "n" ,on;",,,,, raLe', """",1 l,erw,Lage, houdy I,o,'-,,,p,,,, "n(1 ,'n"",,1**hr:s!~f** operat'on eoonr",,1 '" ["o.,,,,,',,,II.,,,,·li,,,, t"',nl on "nnu,,! opera"""

" highest allow'ble pre cOnTrol NOx**em,~<i""** Cd'•. (5)

_Ave",g, Cu"L,u[ CU51 Cfl,,,,ven= (Slt"n) 15 Lhe LeICI".ed 10,,1 Ann",,1 Cu" (I OOOSlyr) u,.'Joo by A""u,,1**~m,,,i"n** ROOll"'O" (10",;1)7). All cosL flg",cs;n**2"[~r.** dolla,-,. (6)

_LTAC lor g"-' ,eb,,'" "I'L"m., i"cI",l. h,gh-p""""re n""ml gas ""I'I,ly ["I'"Ii"" d",,,,al,,,,d G1p"dl "", "fS704,OOOlyr I"r CGR. ,n,[**>J51,O~O** [orFLGR. See fooLLlO«'**#~** "," I[I ""dcrT'blc )-9.! (7)

- LT1IC lor "'0""-,,,0 I'M '011«'"," c"I""'y included in hgni'c reboo" 01""'" oc" '1'1","im"L"ly**~2,(I.l4,OOO** for d,,,,",,I,,,,-,1 ""piMI ,u,1 pILI, S2,527,OOOlyr for ,",,,u,,li,,d O&M ''OIL, [OT. LTAC >lIbtu,,1 uf14.581 ,000lyr. U""Ji,od Am","l NOx Tulal**Avee.~o** Ann".1 NO" Emissions Annual Cnntrol All. F.missions'" Rodudion'" CO'I'" Co,I'" Lab,I'" NO, Conlnll Allocnalive Ton,lvr Tun,lye $I,OOU S/Ion C SNCR wi ASOFA 4,02S 5,909 7,4 ,2 1,26S D Gas Rebum 

### wi ASOFA 4,275**5,65~ n,33~«"**  (,597 C Lignile Rebum wi ASOFA**~,34.1** 5,591 11.338'" 2,037 

# " FLGR wi ASOFA 5,260 4,674 16,990"" J,6.15 A Advanood SOl'i\ (ASOFA)**5,~74** 4.060 2,439 

## on B,scIiuc 9.9J4 0 0 

# ,

_AIL.","ivo 101>,,1 

### na, hecn ''''' ""d from hi hcsL '0 lowest unLl N(h c**'''~,;''"** '.'0

]Jurns & McDullncll 3_2.1 MinnkOl' Powe, Coopcmlivc, In<.NO" BACTAnalJ"lis Study BAcrAnalysis for MRY lit-Ilion Unil I NO" Emission'



### 30000 35000



### Figure 3-1
- NO)( Control Cost Effectiveness

- MRY Station Unit 1 11)



### Milton R. Young Sialion Unil1 NO" Canlrol Annual Removal V5 Levelized Total Annual Cost 

# 40000**TC---c--'==========CC:·===-~-c-~** A

_ Advanced Sep;;",led O\ertirelIir (IISOFA) D. B = Fuel Lean Gas Reburn wi ASOFA 

### c= Lignile Reburn wi ASOFA 0= Gas Rcburn wi AOSFA E = SNCRwi ASOFA

Annual NO" Removal, lonslyr

-------- ---- (I)

- All cost**fi~UTCS** in 2006 dollar.' Numhe« are li"ed and qn,liiicrs aTO not,," in Table )·(2.



### The purpos" ofFigure 3-1 is to show the rnnge ofcontrol and cost for un feasible**NO~** 

### reduclion alternalives evaluated. A dominant "el ofcontrol al!emalives were dclcrmined by generaling what is oalled ti,e "envelope ofleaSl_cost a](cma(i,,<:>,". Th" <lominan( control" cosl curve is the htl'l fit line through (he points forming (he rightmost boundary of(he data zone on a**SC~l(cr** 

### plOI of(he unnual NO

### x rernovallonnagc
versus LTAe for Ihe various remaining BACT alterna(ives. Following a "ootlom-up" graphical oomparison approach, each oftl'e NOx 

### control Ic"Chnologics**~epresented** 

### by a data pointlo (he left ofand**~bove** 

### (he least cost envelop" are inferiorcontrol alternative, per LI1e NSR**M~nual** 

### "n<l should be ""eluded from further aLl,lysis on a eos( efficiency basis.

Minnkola Power Cooperative, loc. 3_26 Durns & McDonnellUACI' Analy.i., rorMRY Sialion Unil 1 NOx EmissioTl-' NOx HAcr ATllily,i, SLuJy

Orlhe lechnically fea,ihle 

### NO

### x coolrol ;llIemalive, considered for MRY Stalion Unil I, dala 1'01Ilt. for convenliormll';%**r~b"m** (Poml 

### D) ami foel-bm gas "'hurn (Poinl 

### B) wilh advanoed separaled**ov~rfire** nir, and IrgllJle rehu'n wid, ASOl'A (Poinl C), lay di&linclly left and ahove the olheJ poinl' ot'the control co"l poml"**s~"ller** plol ofFigure J- L rhese control oplion, arc inferior "mllbercfore were eliminaled from further conlrol co,'l_efreclivenes.' a"alySJS.
Average a"d iLlcremenlill annual co,l" and 

### NO

### x emi"io" reducIion, tor Ihc domioant lea,l-co.l co"lrol allernali,'es remaining**an~r Ih~**  dirTJinaliun ofIhe Ohvlllosly inferior opllons are ]JSle(\ in Table 

### 3-13,**Th~** ,mnu,,] NO

### x eunlrollons pCT year, dJvided by lhe lolal kvdized "noual cool, yield,"n "Ver"gc 11ml cosl (S/lon). Incremenlal cosl effectiveness is a measurc uflhe increase in margmJI cosl effectiveness bclween lWo specific allemalives. The additJOIlJl Ions per yeJr ofNOx control relalive 10 the previous appJrenlleJf>t-co'l curve point, divided hy the increa,e;n levelized Jnnual 00,.-[, yields an incremenlal rmil C"'l ($/10"). Allerrrnlioc]y,**lh~** ;"cremenl"l eo,1 cileoliveness analy.,is idcnlifieo Ihe**rnl~** "I'change ufeosl effecliveness wilh respecl [0 removJI benefils (i.e., the slope ofIhe envelope ofleasl-cost control allernalJves, also called Ihe domlllam conlrols cost curve or DCCC) belween .,uccessively more effeolive nlLemnlive.' which arc con,;dered lechlllcally I""sihle lur Millon R. YOUTlJl S 1;lI;un boiler,_



### TABLE 3-13

- Dominanl Con(rols Cosl Curve Points for

Feasible BACT NOx Alternalives

- MRY Slation Unit 1

() po () g ( 3·12,**"n~** on 'he£,"ph, rh" ,,,"'ornp,my 'his "blc (Poin" B, C, "nJ D were o1im;n"I"I), (2)

- All oost (igmcsio 2006 doH,,,. (3)- A"nu.,1 'n';.";"" "due,;o" ,no level;'," ,'0""01 00.11 ofLhe'" "I1","a"""s " "Io""e 10 ",rrron[ co,l,**"n~** pre-cunlnl! uniL MCl( bllSdinccLmssion raLc. (4)_ In''''IT,,,,L I",," ")XIn cO"'I,ar ;'0"' berwe," oo""cuL,"" ,lremaL,."" (In'",',) I'<lm 10""''' 10 high,.", ",epl " noL,J, IncrcmCUlol Levelizod Lcnli'-cd In<romcnl.r

Tojal Annual Tolal Annual lore.menlal Annual Emi";r,,, Annual Emission Control Cost All.**NO~** Co,jr"'" Reducl;on'" Cnsl""')

### Rrd,rl':~lon("**E,~.cfiwn"",** I.ahol'" Conlrol T..,hni 

# "' I 151,0001 r) 

# " ) ($I,OOOlvcl $!lon)"M'1 ( SNCK 

### wi -"SOFA 7,471 5,9U9 4,n2 1,849 2,694
A AdViUl<ed SOl-A 2,489 4,U60**2,~M** 4,()6U 613 (ASOFA) 

# , Dom"""L conlrol, eostcurvc in" rrom lowest ASOr" 'oh, he" SNCRwIASOJ.A are l,b,ko Lh, 

## "m, lIS '" Table

The incremenlal coot analysis indicales lhat from a cool elTeclivelles< viewpoiol, lhe SNCR WJ;h ASOFA**aUC"ma~vc** i"ours a "'gnilioa", aLlLlual (leveli,."I) incremenlJI cosl comparcd 10 Ihe ASOl'A NOx comrol

Ilum' & MoDonne1l 3_27 Minnko13 Power**Coopeffiliv~,** lno.NOx BACT Analysis Sludy BACT An'ly,is forMRY Smlion Unil I NUx Emission.
technique (slope from 7.ero baseline 10 ASOFA, I'oinl A was $6n/lon for MRYS Unit I; the incremenlal co.t (,lope) from ASOFA, Poinl A to SNCR with ASOFA, Point E was $2,694/ton for MRYS Unit 

### I.
Figure 

### 3-2 ennlains a repelilion ofthe levelizcd lOlal annual eUSI**~nd** NO

### x control inform.tion from Figore 

### 3-1 for MRY Slation Unil 

### 1, wilh Point 

### B (FLGRTM wilh ASOFA), Point 

### C (Lignite 

### Rcburn with ASOI'A) and Point 

### 0 (conventional gas rebum with ASOFA) removed. This i, Ihe dominant cOl\trol, eosl ourve for MRY Station Unit I NO

### x emi".ions alternative•. 

### Figure 3-2
- MRY Station Unit 1 NOx Control Altematives BACT Dominan! Controls Cost Curve(l) 

# ----==
Millon R_ Young Station Unit 1 NOx Control Dominant Controls Cost Curve 6,000 

# I Slope = inorem8nlal $/lon 7,000 A= Ad",,"c'" SOFA 

# i**,~** 

# " E SNCRw/ ASOFA 

## , 0 

# ! >1 z 6,000 (POint. B, C. and 0 ferm""') 

## " 

# • '" $2,694/lon

### ~' 

# • 0 5,000 0 

# .. 0 0 

# " 0**~~** 0 

# - 4,000 0 

# • 3,000 0 

# , " 0 

# • " 2,000 

# .. $6131100 , 

# , '\. , " 

# " 1,000 ,,'
, 

# c"

" , 

# ... ' ' ' 

# "" 1,000 2,000 3,000 4,000 5,000 6,000 Armua! NOx Removal, tonslyr
(I)

_Ail oost**fi~UT<'** in**~OO(,** dollar

.. Numb<:" aro li>t,d and quali"crs OTe """d in Table J·1J,

In the U.S. EPA's NSR Manual, the EPA does not specify ueceplahlc or**unacc~'pluble** ranges for avcrnge (un;l control eo,t,) und incremenlal eosl cffC<:livcncss values. As can be ""en from a review ofTable ]-**]~, Ih~**  average levclio<cd control cosl effeclivcnos" (e"lled lhe unil conlrol COSI in Ihis report) r"nges rrom approximalely $613!lon 10 $6,597/10n ofMRYS Unil l's NOx emissions removed. 

### It should be nOled,
Minokola Power Coopera'ivc, Ino. 3-28 Bums & McDonncliBACTA".ly';, for MRY S"'-llOn Unil I NOx Enn«;on, NOx BACTAnalysis Sn,dy

however, lloullhc**hi~cSl** eBt;malcd average control co.'L< inoulvc 

### gas rcbum lechnnlo"ics lh"l were .,hown 10 be ",ferior oplions (nol on lhe dominunl conlrols cost curve) and lhus wcre elimi"aled from further iml'acl$ onnlysi,.

The iLlcrcm"nlal cosl dTecl"

..eLless 

### i, " measure of**Ih~ ,n"r~u,c**  m marginal cost el1tclivcnc" belween lwo spccific alternalives. AIltmalively, lhc incremental cost ell"clivene,> analy,i, idenlilles Ihc ratc of chan"e 

## or,·u,l effGct,veness Wilh rc'l'ccl to rem"vnl benefj ls (l.G., lhe ,lope of**lh~** lea,H,o,l envelope of dom",anl contlOl aILemallvco or dom",aJll conlrol; co,l curve) between <uccc,-,ivdy more ejjtclivc allcmalives. Thc economi" impacl analy,i, indicale.' lhal 

### f, om a co"1 efftcli"e"e" viewp"j"l, lhe highe.,t performi,,?, nllmmllvc i, SNCR willo ASOFA {Poinl Fl. 

### This conlml oplion "co""i,krc,1 lc-dmically 1"0.11bk fOT Millon R. Young Swtion Unit I**boil~r** bllt incur, a sigmfic"nt an"",,1 (kvclized) i"crerncn",1 eOSI relative lo the next highest fc"sible NOx cOnlrOllCehnique, ASOFA (PoinlA) when ASOI'A is comp"rcu again"**th~** pre-eonlroJ**b"Belin~.** Thc Ad",mccu**Sep"rat~d** Overr,r<: Airallernative Ioa$ "n av"rage unil conlrol eo,l ($613/10n) appruximalely 48% ofthe highe.'l p"rlunning I"asible nhnnalive on lhe domlll"nl control, cosl curve 

### (SNCR with ASOI'A, $1,265110n). ASOI'A also 

### 10", a much lower iJlcR"ITll"llWI cosl per lOll**r~lnliw** lu Ihe**pr~·cnTllroJ** bu,clinG ("lope from zero 

### 10 Poml A., 

### SG 13/10n) compared 10 SNCR wilh ASOfA (Poinl E) "e",,1S ASOFA (Poi", Al; Ihc ,Iupe from Poinl A 10 Point E

was .n,694/10n.

The otkr c!<om''''l' ofthe fourIh 'lep ofH BACT a"oly.,i, followmg: ,·conomic**ilTlp~"I,** "rG 10 cvalun1e thc fullowing lmpJcls oft"o.,ihle cm"sion conlrok

• The energy impacl".

• The enviLon",ent,,1 imp"cls.

Dums & MoVunndl J_19 Mi'mkobl Power Cooperrll;.e, Ille

# i i 

# , , ] 

### I 

# I I

> 

# ! " 

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# ,NOx BAC!' Analysis Snody**----~-~----** BACtAnalysis for MRY Slalion Unil J NO" Emissiorn



### 3.4.2 ENERGY IMPACTS OF MRY STATION NO

### x CONTROLS



# • r.; '1

';.**~<** 

# • OpeI1ltion ofthe most cost-effective NOx tonlroi technologies considered feasible for potenlial applioation at tlte Millon R. Young Station impo,c direcl impatts on the tonsumplion ofenergy required for thc prodnetion ofc1eclT-ical power at the facility. The details 

### ofestimated energy usage 

### "ml costs 

### for the various 

### NO" control nltomnlives arc s\lmmari7.ed in Appendix 

### C3.

Control aItemative., for reduction oENOx emissiqns were reviewed to delennine ifthe use ofthe teohnique or lechnology will resuh in any significanl Or unusual energy penalties or benelits_ There ore several basic kinds ofenergy impacL' for NOxemissions oonlrob:

• Potential inecc"se Or decrease in power plant energy consumption resulting from a ehJnge in lherm"l (heat) energy to nel eleClrical oUlput conversion efficiency ofthe unit, usually eJ<pressed
as an hourly unil heat rale (BlulkW

### -m) or lhe inverse ofpounds ofpollulanlper unit eleotrical power OUlpU[ (MW-hr)_ This mayor may not ch"ngc thc nel eleclrical output 

### (MW) cnpacity of lhe 

### EGU, depending on iflhere are physical 

### or imposed limits on lhe lotal heal inpUlto lhc boiler


### or ckclrical powe, outpUl. Polenlial increa.,e or decrease in net electrioal oulput ofthe Urnl, rcsulling frum changes in physical optn>lional limilalions imposed on lhe ability to sustain a fuel heat input ralc (mmBtulhr) which results in a polenlially lower 

### or higher unit nel eleclncal output (MW) capacity_ This is effectively" changc m net declrical output (MW) cnpacity oflhe 

### EGU_ Potential increase or decrease in nel electrienl ompul oflhe unil, resulling from cl,anges in auxiliaryelectricnl**POW~T** demand and usage (kW, kW-hrs)_ This 1S effcetively a change in net electrical output (MW) capacity ofthe EGD.

• POlenlial increase or decrease in reliability and availabilily to generate electrical powcr. This results in a crumgc to lhe number ofhollis ofannual operalion, nol necessarily a change in nel electrical outpul (MW) cap""ily ofthe 

### EGU.



### 3.4.2.1 ENERGY IMPACTS OF SOFA TECHNOLOGY 11,ere should not 

### he a major imp"cl on energy eon,umption resulting from the opcr"lion ofale advanced varinllon ofDsepariltc<l ovcrfjre air sySlem. SOl'A does nol signific"ntly change lhe tolal "mount ofair introduced into lhe boiler, only lhe location where it is inlroduced_ Damper re,islance and supply pressure imp"clS oflho SOFA system on fan power consumption should be insignilicanL The am"un! "f flyash emilie<! from lhe ooiler is expected to be rcducell 

### (b' than fivo ]>CTccnt) from the baseline level
Millnko!a PowerCouper'live, Illc. 3-31 BUm5 & McDOllllellBAcrAnnly<i.' rorMll.Y Slalion Unll 1 NOx Emissions NOx BACT An.ly,is STUdy

when tl,c SOFA syslcm is 

### in [\ill operalion. Slighlly higher levels ofunnun,ed caL'hon III lhe llyn,h may**o~cur** wilh the operalion ofa SOFA syslem. This could have a smull ncgmivc impucl on Ihc planl heat rale (higher lltu!kw-hr). The.,e change, nrc**c~JlC"ted** to bc wilhin the lypical range ofcurrent operalion.

There i< a rmenlial reduclioLl in ,eEahiliry und**u~uilab,lily** of" lib'llilc-fircd cyclone l,oiler to gencrale Hleam 'Or productiun ofekclrio"l power a< a resul! o[ ,,]Stalling and ol""rarjng a .,epnrated overlire air sy'lclll. Typical SOFA operalion on hitum",!)u, 0'**w~,tcrn ~uLLitunn"ous**  wal-f'rcu cyclonc bOIler, does nm carry 11 sib'llilie,'''l ad,lilionul risk ofcall,ing insufficicnl or exee",ive accumulation ofslag wilhin lhe cyelonc barrels Or furnace bollom compared wilh non air-staged comhu'lioo. Reliahle hOlier upLTJlion depends on avoiding <uch adver.<e condjlions In the cycio<\e, and lowcr rurnacc, whIch cuuld reqlllre a forced outage to remove the ,olidi (lcd ,;lag prior 10 rcwmmg Ihc boiler 10 generalion production ,ervLce.

Thc eh"lknges ofmainlaining adequate slag layer deve]ormen1 and now "'hile liring Jignil" in MRY Um t I', cyclones under cxcc"" air conditions h"vc bOL'T1 signiIicant during lbe operaring history oflhe powcrpl,ml, Minimizing forccd oUl"ges resulling from cyclone .,lag ;"ues have Iargdy bc"" ,;ucccssful lhrough operatIOnal praclJce., that do not affecl day-lo·d.y boilcr reliab;lity anu availabIlity. Due 10 lhe va, iahjlJty ofCO",h"Slion**chamClcriSli~,** uflignite ,upplied from Ihc Center mine, and lhe dependency of lhe slag now onlhc lC'T11pCTalurc wilhin the cyclone bJlTels or furnace bollom, condillOn,; may OcCOr dUTing ASOFA operallOn Ihal exceed Ihe ahility to adjuST operational

### praelic~, suffioicntly 10 aV<J1d forccu 

# .1; oulages 10 remove the solidjfLed ,Jag.

The polential iml'aCl on annual unJl**oper'~ling** time dllc to**~ydone** ,lug issues associated wilh air-staged cydones!ASOFA**sysl~m op~mlion**  was eslimaled to he approxllnntely 2% n::uuelion from Ihe assumod pre-control baseline availability. i.e. 0.97-0.02=0.95. n,e e.'ljmaled eleclrical gcneralion produclion lost due 10 the reduclion in MRY U",l I's a"nual availahil;ly is shown;n T.bIc 3-16.



### 3.4.2.2 ENERGY IMPACTS OF SNCR TECHNOLOGY For SNCR, lhe injeclion of" diluled urea solution wllll'equire some addilionul ",lXlliary power for hearing and pumping the hquid and (I,;mg eomprc"ed air [or alomiz"lion and conling Ihe**rc"g~nl** mjocl,un nozzles/lanccs, on Ihe order of70 to 100 kW. The injection ofwatcr (uscd for urea dilulion) illIo lhe bo'le' flue ga, also wi]] have 

### 3**~m"ll** ncg"livc i1111"'cl On Ihc pIanl heal rare (hjgher R!r'!kw·hr), "llhough lhc vendor ofSNCIl <ystem., advise,; l1,allhe heallelea,ed from thc o"idalion ofa portion oflhe 

# Li",," &. McDun"ell J-J7, Min"kolO**Po~'er Coupcrdliv~,**  Inc.NOx BACr Analy,i, Study BACIAnaly,is for MRY S,"uon Unit I NOx Emissions
injected urea compensates for this impact. The impact of**~dditional** nue gas created by operation ofan SNCR-rclaled system on fan power consumption should be smaiL

There i.' a polenlJal reduotion in reliability and availability ofa lignite-fired cyclone boiler 10 generalc slcam forproduelion ofeketrioal power as a resull ofinslaJling and operating a SNCR-rdated sy"temTypioa] SNCR operation wilh low ammonia slip when llring low-Rulfur weslem subhituminous coal in cydone_Jired hoilers doe:; not carry a significanl addilional risk ofeaLL,ing**exces:;iv~** fouling ofthe lubul"r"ir prehe"lcr compared with non-,SNCR operalion. Reliable boilcropcmlion dqx.-"T1ds on avoidjng adverse fouling; conditions in lhe air preheatcr, which could require a forced outage 10 remove lhe ash deposits prior 10returning the boiler 10 gencralion production "ervice.

The challenge" ofmaintaining open pasS'Jge" lhrough thc**~ir** prebealer tube.' wbi1c firing lignile in MRY Unit I's cydone:>**uu<l~T** typical condilion:; have been minorduring lhe opcT.ting hislory ofthe powerpbnt. Minimizing forced oUlagc"S rc:>ulling from a:;h deposits wilhin lhe air preheater have largely been**suo~=,fullhrough** operational praclice" that do not nITect day_l.o-<lay bOIlerreIiabjlity and aY!'iJ.bllily. Due to lhe variability offouling**~haracleristi~"** oflignile supplied fTum lhe Center mine, and**th~** dependency oflhe fouling wilhin thc airprehcaler on wdium, 'ulfur, and ammonia slip cmi,sion levels, condilions may occur duriug SNCR openllion thaI exceed lhe "bility to adjust opernlional**pr~eljces** suf;fi.cienlly to avoid forced oUlages 10 remove thc nirpr<'healer deposils_

The pOleminl impacl On annual unit operating time duc lu "irprebcaler lonling and Olher rotential issucs ossociolc<i wilh SNCR syslem operalion wa"**~stimaled** 10 bc an incremenlal 1% rcJucljon from the assumed pre-control b"scline Or ASOFA availability_ The estimated cleclric"l geueralion produclion lost due til Ihe reduclion in 

### MRY Uni!]'s annu.1 availability is shown in Table 3-16.

Minnkolo Power Couperali"e.1nc. 3-33 Bnrn<&McDonnell[lACr Analysis lur MRY SLaLion Un'l 1 NOx Emissions No... BACT Analy,is Sn,dy


### TABLE J·15
- Expected Auxiliary Electrical Power Impacts for NOx Controls

- MRY Station Unit 1

E,limnlcd Allnual**Avera~e** Auxiliary E1C<',ri<al Pnl>er Demand and COnS""'pli"n 

# ,,, N(h C,mlcol F. 111 mCnl All. Gro,s**J)e",and~l** Power (hage'" Labd,n NO <Co"l rol Tc<hnique 

## 'W kW ImJ c 

# , SNCR wi ASOFA 

## n**582.~11** A Advanced SOFA (ASOFA) 

# ,**8,O5~** (I) Al'o,",,,.vc nu",be< 1,,,-, b,"" PTcv,ou,ly m,g,len f"'m h'gl",," 10 IOWO<l uoHl NO< O""'>r"n role. (2)

_ The "PC NO, "1"ipmcnL gro'-' ,uxlli"y dc, ,nc.1 poword,,,,,u,d nr"I,e",",iv,." " 'he 'u"' o[ ,,,,I;v,<1L1,1 «chonlng,,,, combJllcd by ,m'ple ",1,hL'on, AcLUal POW", d,m,md, ro"y d,f[cr fmm '1\;< 

### .I,," '0 po,H,VC 0' ""I}'l;vc ,ynorgj"" <fTc"". (J)

- nc annual 'ha"ge in APe NO, <qUlpmoll' "",iliary e1wricol power dem"",1 eI'c1ric;lj' u"'go in k W-hrdyr for Lh<.", ""'''"''Iivo> " the oct power der",,,d mulupJ"d by LI,o eSI;m,tlctl a"ouol op<m'lng limc "nd rullmng 1'1,,,, o'!",oily faClor whiel\ 

### ,,,11,,,,, 'n" A<tiu"mcnL rot 

### "ny 

### "'pcrlro rdi'biliry and eap'"'Ly imp,cls fmm 'h, ;mplomcn""o" of Ih" ,onlrol Lcchniquo. A**"c~""vo** "duClion m Boo,o,tt'i"n " ao in'''''' JO ,,,,,,,AI ""'" 01""[1'1001 I'''WO; .v,ilabk [or ",Ie. 

### TABLE J-16
- Expected Electrical Power Generation Availability and Capacity Impacts for NOx Controls

- MRY Station UniL 1

yg gl p g (2) O""I;ne ,vollob,lily 'S """"cll aL 97,3 poreenL ncsc v,lues 

# "fl"" ",,,,,,,,,,,1 ""oun" ofnogaL,ve rcl"biJlLy ,mp"L "'I'CClod fron' ,I" ""pl'm'n,"Lion oflilo i",li""lu,1 NO>: conleol [ech"i,!"c, (J)

- Annual 10<1 "perdl;ng 

### "01>0 Tc,ol'lng ['Om 'hc impl,men",,,oll on],e "idiv,do"1 NO, co'''",1 'c-c"mqoc is Ihe d,n",o"," beTwoen 'hc ""seline ,,,d e<pe<"d 

### a""",1 OULogo' 

### '"ne<. (4)

_ ll",di", ru,mi"e pl,nl C"l"'cHy faClm "''''omcd oL 96." I,e'<e'''. T'h"," v,luc:s ",fi,eL "lr"""cd anlOU"" of"c!:,,',vc rdi,I"li'y 'mp,cL ",poeLed lr"m 'hc ,mplom,n"L,,'" "r'h" indiVidual NOx ,,,"[rol kchnigLic. (5)

- A""""I dCClriciLy gel",'L,,," rctIocLion lS on"u,1 ,,,locMn o[opem'ins Li",e "'ulJiplied by Lho ann"a' "'nning planl ,,'p,ciLy f'<lor**,,,-,ulrin~** fmm Lhc ,mpl,,,,e"'.l;"" o[lhe indJVid"al NO, 'onlroll"hnJque m"I"pliro by 'he Mel( C'I""'y r.llmg nr 2,3 MW (Mel( gro« 

## ""it dwncol OULp,L cal'"cily),**E'lim~led** F.'Hnmtcd Eslim.ted A"nnol AnnllO[ Anl1l1.1 Average Avecoge**Aveca~o** hlimaled Operaling Running EI"d.-idly

Annual Time I'lon' (;ener:alion All.**Av,ca~e** ll.edlldioll, Cal'adly K"t1udi"n L.bel,n 'NOxCo"lnJl. Tedm; 

# "' A

### va;labj]i~",') brslY"'1 F"clm") kW-hnly,-J" 

# , SNCR wi "SOFA 0.956 273 0."65 67,660,606 A Advancod SOFA (ASOFA) 0.952 

# '" 0,%6 4fi.586.546


# '" AlLornaL,"" "limberhos ""eR "ev,o",1 

## '55' nro 1'0.0 Ie-A,L <cm"v,1 '0 hi "," Tomoval "rccn", 

# ,

Hum' & Mdlormdl ]-]4NUx BACTAn,lysi, Sludy 8AcrAJllIlysis for MRY Slalion Unill NUx Emission;


### TABLE 3-17 - Expected Total Electrical Power Generation Impacts for NOx Controls • MRY Station Unit 1

() nmbr I y g g»C B (2)

- Thc ,nn",1 eltonge in APCNUx cqnipm,nl '"'iliarye1ectricol [!<'wc:rdemand cl,clricilyr""E' in kW-hrslyr for Lhese ,lLom",i"", L, Lho ,,", [!<'werden"'nd mulLiphedhy the estimated ""nual operaLiog Limo and runniog pl,nrcapeolLy f,o,", which ",n,cl, the ",ljU>L,,-.,n' ro, 

## '''y e<poOled ,elJabili'y andcap,cily imp'"" r'om**~"** impl'meo,"LJon o['h,**conL~\1** lochniquo, AnogaLl'O Tcu"c,ion in g,ner"'ion i,"n in"",,,o in ""ouol n,w <Ioclri"'l row" '''''il"blo fOT ""I<, (:l) -l\onu,1 ol""LridLy genom'ion rednoLion " ,nnual roduellon ofopmlLing 'ime mul[ipliorl by Iho ann".1 running pl'n' o'raci1y 10""' ""ulli"£ from the Jmplomcnr:IliQJl ofrhe iedividual NO:< oon[fol occhnique mulriplied hy lJ,e MeR "l",oily r.[rng of2,) MW (MCR**~ro""** "nil <l<o"io:1l "ulpuL <op'cily). (4) -l\onu,1 eh,nge in ne' dCCLocal powergcncr;Ilion avail,blc [or "Ie 

### ;s ,riLhmclic ,nm ufann",1 powergenr:",rwo reduelloll due Lo , change ln Ihe a"xili,')' elewkal !'Owerc""'timed pi", dIe 011"",1 ge"eraLion rOO"Ol;O" [rom, deore"e m'nnu"1 o>'CTl'ling lim' ,nd """go anno,' ,unning pl'n' c'r,city r"lor "'Stilling rTOm lho impl,m,nt"ion orthe**in~iviun,1** NO. oonlrol [cohnique, eompllrOO wil" oo,olin"- E,lim,ted Annual**A~e.,age** ESl. Tot,1 Annu,1 Elootririly Ch,nge. in Power Gonera,ion Nel £1'0"'0,1 PDwer All. V••go'" Redu<liun'" Goner.lionA".ilahle fo' Label{l) NUx Cmu",l Te<lmioue

### kW-~"lvr kW_ltn/ r Sale'" kW-lt,sf 

# , 

# , SNCR 

### wiASOFA 582,411 67,660.606 68,243,017 A Advanced SOFA (ASOFA) 8,058 46,Sg6.546 46,594,605 

# , AlrernoL,," 

## " e 10,,-, b,e" >reviou'] -; Red r'Om 1""-,, ,.."..,,,,,1 [0 ili he" "mo",,1 rcenLa e.



### 3.4,3"-0 ENVIRONMENTAL IMPACTS OF NOx CONTROLS - MRY STATION NilrogC"Tl oxidc" [C"et wilh oxygen in the almosphcre lO produtCC elemental nitrogen amI OZOnc 

### (0,). This is one ofthe common caus,," ofviSIble pollulion in the atmosphere**rcf~TIcd** to as "smog"

_ Operalion of lhe variO)-lS NOx eonlrol technologies considered lor polenlial ,pplic,tion ,t the MiHon R. Young Slation impose direcl and indirecl impacls on the environment. The most pronounced direct environmental impacl cxpcoteu [rom operelion ofany or(l\e NOx COLlIroI options considered is tile reduotion ofozone 

### umJ improvemenl in almoJ.',pheric visibiJily (i_c. rcuucc<l visibilily imp.inneut) downwind orlhc facility_



### 3.4.3_1 ENVIRONMENTAL IMPACTS OF SOFA TECHNOLOGY The operation of, separaled o"erfire air system is expected to slighlly inere"se carbon monoxide concentration, in the slack flue gas. The advanced [mm ofSOFA ahem,tive is expecled 10 slighlly lower Ihc nmounl ofparlicu!"IC mailer cmiued from thc boiler**~nd** mIly mise the amoum ofunbumeu carbon in lhe Jlyash collecled for land disposal and emitted to lhe almosphere by small incremenls. Allernatives involving fonns ofgos rcbum should c:<pcricnee lower parliculate emissions, 3m! , reduelion in the
amount ofhoilerl'ollom and flyash requiring disposal.

Minnkola PowerCot,pcrali.<, lnc_ Rum, & McDoundlBACT AnalY"i., fOJ MRY Slolion IJnil I NOx Emissions NOxBAcrAnol)"i., Stndy

The**envirOllmcll~11Imp~ct** limll**potenti~l** reduclion ofannual unil operaling lime by approximately two percellt clue 10 cyclone slag issues associated wiLh**~ir_slaged** cycloneslASOFA ,yslern opcl1llion will 

### be 10 n;ducc the annual amnunl (10m) ofnitrogen oxides emilled. "nd thcreforc Iho annuul number ofNOx 10m remov"l1 wi]] inc",""", by approximalely Lwo perceLlI.



### 3.4.3.2 ENVIRONMENTAL IMPACTS OF SNCR TECHNOLOGY 0l'emlion of;, eonvcnLiom,1 SNCR syslem is not expecled to sigLlificanLly impact emi"ions ofCO Or vol"lile organic compounds (VOCs).

Orel'ation or**~n** SNCR**~y'l~rn** w,ll normally**er~"le** a small amounl ofllnreaoteu ure" or ammonia to be emille,!. The amounl ofammuni" siJp produced hy SNCR depend.< on the amounl orreagent ul,h""lion
nnu locaLion oflbe injeclion poinls. [[igher SNCR NOx rcduoIion**p"rronn~nce** involves b'I"C"ler amounts ofreagenL usage and ammonia ,III'. Thi, " lypieaUy conlrolled (o!c" lh"n 10 ppmvd, especially when Lhe ro.,.,'hle fOTIIllilion of**wlfllle~** weh "' ammonium ,ulrate l(NII,),SO,] and ammonium bisullale fNH,HSO,] 'vill be more problemalic at higher .,[ip levels. Sullur lrioxide (SO,) fonnecl during "OmbU"lion iLllhe boiler CO" combine Wilh ammunia during p""agc lhrough Lbe nue ga, ducLwork 10 (0"" lhe s"lf;,ICS.

Some ofLhe unreacIed ammonia from SNCR operal;on WIll**b~** eollecled wilh Ihe flyash in the electrostatic rl'ecipilnml'. A"y remaini"l: ammoni" ,lip IhaL i, not collecled or conden""d in lhe a;r poHulion conlrol syslem ""ill 

### be emilled from the stack as an aerosol or condensable parlieulale. This h,," Lhe**POl'-~'li~1** to iuerc;"c almo,pherie visibilily impamnent downwind ofthe facility eompaccu wilh a pri'lme conclilion. Ahhough lhc predicLed amounl of,uell pOlenlial impact from ammonia slip emissions has not been determined, il is expecLed 10 he**~m"ll** in eOmPllriSOn wilh Lhe sib'llificanl anlicipated reductJon In fal'-ficJd O7<.>ne a,;d improvemenl in almospheric vislhJlity as a resu[( ofIhe overall**NO~** emi,"iOrl reduelion.
Delivery ofLhe urea reagent lO lhe powerplanl f"eilily and sLomge ofaqueous mea reagent on-"ilC CCC"le, the pOle"lllial fur "ccide'llLs, leaks, and subsequent releases 10 air, ground, and surla"" W"ILT immedialely surrounding the f"eili ly. Ure" i:;**""J~h** !cos VOl"liJe than anhydrous or aqueous ammonia, and Ihe."c mks ale expecle,llo bc manageable. Emergency plaLlnm!\ alld communiry communiea!lons are part ofLhe m"nagement Illan requiremerll, JOI' such reagcnl usag-e.

UU'"s & Mcllonndl J-,6 Mmnko", Power Cuuperalivo, Inc.NOx BACrAnaly.i. Sludy BAcrAnalysis for MRY S",tion Unll 1 NO" EmissiollS



### 3.4.4 The environmental impact from potential reduction ofannual unil operaling lime by approximately one percenl dne 10 air prehealer fouling issues as..'<Ocialed wilh SNCR syslem ope"'lion "Vill 

### be to reduce lhe annual amOUn! (IOns) ofnilrogen oxides emilled, and lhercfore lhe annual numberofNOx Ions eliminated rd"live to lhe conatant pre-control emi"ion baseline will increase by approxirnate]y one percenl.



### SUMMARY OF ECONOMIC, ENERGY AND ENVIRONMENTAL IMPACTS OF MRY STATION NO

### x CONTROLS The economic, energy, and environmental impacts ofeach feasible 

### BACT allernative evalualed for lhi, S(\ldy is ,ununmized in lhis Seclion. Tablc 

### 3-18 aumm,,,izcs thc various impacl' discussed in Sections 3.4.1 lhrough J.4_3_ n,e economic analysis el<amined lhe capilal cosl ofcach feasible 

### BACT alltm"livc evaluated and any other l'owerillant upgrnde costa necessary 10 implemenllhe al\(:mulive. 

### In addilion, the economic analy.,is examined the ol'e",ting and maintenance cost associaled wilh the highcsl-performing forms ofeaeh fca,ibk 

### BACTallcmulive evalnal,,<L These eoslS were lhen combined inlo the levelized tOlal .nno"l "0'1 for a comparativc asscssmcnt ofIhc lol"llmplemcnlalion cosl ofeach alternative. Finally, a, part oflhe top-down analysis, a dominanl controls "ost curve was plolled and lhe unit control cost for each allernative was evaluated. Two alternatives were on the domin"nl controls cosl ""rve and lhus were ioJenlifi"d .s Ihemore cOSIefieelive ullem.lives. The IWO BACTNO, control a](ernative., evalualed for in"rcmrnlal cosl, energy, and environmental imp;lcls applicable to Milton R. Young Slal,on Unit 

### 1 were;

•**SeleG~ve** Non-Calalytic Reduclion (SNCR) combined with a special form ofscparutc-<l overIire aIr(SOr-A) specifJcally roO" hgnite-fired cyclone boilers (referred 10 as Advancccl SOFA or ASOr-A); and

• ASOr-A alonc_**Min~kola** PowerCoop''''li,e. Ine. 3-37 F1ums & MdlonnellBACT Analysi., [orMRY**SIa~oo** Uni, I NOxEmi"ions NO" BACT Aml)"is Study

-----------------------

( ) B g (2)

- E,timaled NO, controllevcl reduction, relalive ro ayr. :md aMu,1 hrd'/T opennion compared ro pre-control oo,.lino bose<! on (3) -lnslollcd capilli! costi, ostimaled forclet<rmination oJ capacity included m hgniLe rebum opLion are**~23.S61.000** for inmillcd C[ (4)

- Annu.l opmlling and mainlcml1lco co'l [or aplIrticuloh i, Ill. high,,, oonscounv. 12·momh, of**opm~on** from**2001_200~** (5)

_u.velized To

..l Annoal Co", An"!l2li",d 1",""led LIIal O&M cost" 1.24&73 ammalizcd O&M costfuctOT. (6)

_Average Conl",l CO'1 ElIer:Ijv"",,,**(~llOn)** is Ille Lo' (7) ·!ncrelTh."II'ol Control eo" E!!',erivcn= (l>Ilon) is Lbe (8)

_Energy jml'Ool' are inorcmrntal auxiliary oleeltio.1 p.(kW.blSlyr). (9)

_ Environmenllli irnpam ,ullllTIllTiz<: expcdcd non·oi, cenlr:llion, Ilk'ly will

inc"""," willl ai,_.=ging oy<lones. Ex""ss umea"., 

### TABLE 3-18 Summary 

## ofTo -Down B l''\.CTS ENVIRONMENTAL IMPACTS Inerement,l I.nnll.1**AII~.** o...-er Usage Emission- Generalion 

# ,,"- R.t.**'l.edl1C~onl"'** , Noo_Air ToxieAir Labelll) NOx Comrol AUHualive Ib/mmBtJ.I<W hrsl T Increase Iner""se E SNCR 

### wi ASOFA 0.355 68,243,017 Fly.,h UBC eO,NH,
A Advanced SOFA (ASOFA) 0_5 13 46,594.605 Flyasb VBe 

### CO Ba,eline 0_849 

# , • Al'e,nal;"e l.bel hos !><eo ""i ned [romh; he" ro 1<



### Burn. & McDonnell Minnkola Powo, Coopomlivc, loc.

### BACTAnaly:si., forMRY Srnlion Unil I**NO~** 

### Emissions**NO~** 

### BACrAnalysisStlJdy



### 3.5 BACT RECOMMENDATIONS AND CONTROL LEVELS - MRY STATION UNIT 1 This repOrl prcoC'1lts lhe analysis ofcontrol technologies for nitrogen o"icles (NO,,) forMinnkOla Power Coopcralive's (MPC's) Millon R. Young Sialion Unil 1 using lhe EPA's "lop-down" BACT appn>Hch. BACf is an emissions limimtion for each pollulant from Hsource cletermined 10 be ;Ichicvahle using control**technolob~es(s)** 

### that provide the ,.mH"imum ']cb'reC ofemission recinclion

...taking into account energy, environmental. and

### e~onomie impacts"]'. A BACT review docs not resull in a percent removal eITieiCTlcy requirement. The generally acceplcd procedures for plTfonning a BACT analysis are oullincd inl1,c EPA's draft NSR Manual. The 

### BACTanalysis for Millon R. Young Station NO" emissions was performed in accordanec with lhi.' proccdure. The EPA' ., drafi NSR Manual outlines five basic slcps Ihat are 10 

### bc followed in tl,e "lOp-down" BACT evahmtion. The.,e steps were a, follows:
Slep I - Iucnlify All Conlrol Technologies Slcp 2 - Elimlll3tcTcdmic:ally IIIrc"sible Oplions Slcp J - 

### Rank**R~'1l1aining** 

### ()lI\!rol Technologics by Control Effectivcness Slep 4 - Evaluate Mo.,t Effcelive Controls und Oootlmenl Re..'tllts Step

. ScleclBACT

n,e unal restlll ofthis analysis is a recommemblion ofIhe BACT allcrn.live and the associated NOx cmission rule lor Mmnkola Power OJ<Jp=tive's MiHon 

### R- Young Slalion Unit 

### 1. The emissionlimilalinJlS ror a generation fucility are expreo:sc<l ;n a pounds per million Brilish TI\ermal Unils (lb/mmBm) basis.



### 3.5.1 UNIT 1 NO

## x BACT In slep one ot'the tcehnology evoluatiun. three basic calegories ofNO

### x controls for EGUs were_ identificcl: pre-<:ombu<l;on, combustioll, oml posl-<:ombuslion. Elcven basic types ofNO

### x control prnce«,es were iclentiued wilhin lhcse three ealcgorios. Twenty fourvanations ofthese elevcn pmeesses wcre reviewed roravailahility nncl Jpplicability to cyclone-fired EGUs burning North Dakola lignite. 

### An ·'Juvanced" form ofSeparatccl Overure Air. alone and 

### in various combinUlioos with Lignile Rebum, Sck..:tive Non-Cal<llylic Reduction (SNCR). Conventional Gas Rebum and

JO Ibid. 

### NSR Manu.l D. I 

# '.', 'i

## ':~'<>~:-S~h

Bums & 

### McDonndl 3-39 

### Minnkol, Power Conpe",livo, Inc.NOx BACT ALlal

....JS Srudy nACTAnalysis fnrMRY StatioD Unil 1NOx Emis.:;inns

------ 

## -------_....

## _- Fuel I,ea" 

### Gus Reburn

### TM, was evalualed for eosl-effectiverlcss. TI,e cOHt-eITecllvene", analy.;i" indicaled that ASOFA alone,:mJ ASOFA wilh SNCR were cost effeclive allcTIllilivcs for

### l'VIRY SLalioTi Urlill NO

### x cmmoL The energy and environmenl.1 imp.cL, .,,"lysis for MRY StaliolllJniI I '" cosl-dTcellvc NO

### xconlrol 

### allernmive., we, 

### e gencrally**insignific~nl.** Ba,ed upon the defimlion of

### BACT and lhe re,ullS oflh" 

### BACT "n.lysis, Sele<Olive Non-Calalyllc I(edocllon (SNell.) 11\ comblllulion wilh •**spcci~l** form ofseparaled**oV~Tfirc** air (SOFA) specifically Ii" lignile_I,ml cyclonc hOllers (referred 10 us AdvaLlced SOl'A or ASOFA) is recommended a, Ihe Bc>l Avail"bk Control Tcchnulogy I,l' nitrogen oxide6 cm,,>ions from Minnkola Power Cooperalive's Milton 

### R_ Young Siulion Unil 

### I. The lInil BACT NOx emi"lOn, ralC fllr 

### MRYS Unil I i.' O.3S5 IblmmHm, determined a, a roiling l2-momh average. ThLS is shmvn in Tahle 3-19.

TABLE 3-19

- NO

### x Emission Control Technology and Rate Recommended as BACT for Milton 

### R. Young Station Unit 1

Control Technoloqv and Emission Rate Recommended as BACT 12-Month Rolling**Ave~age** Unit Pollutant BACT Control Method BACT NOx Emission Rate {lblmmBtu) Seleclive Non-Cutalytic 

# , NO, Reduclion wilh Advanced 0.-'55 Sep,naled Ow'din:**Al~** (ASOrA) '.'

## , ,

3.5.2 EMISSION RATE LIMITATION RECOMMENDATION Til complcle lhe 

### BACT dererminalion process, lile Con.,enl Decree (CD) require, that '·,pecil'o cona'ol lcchnologies 10 be insi<.llkd a"d " spooific Ph",c 11**~O-Juy** l\olling Avcwgc NOx Emission Rule limilalion (lbsIMMBIU)"" (pIlun,b; po, mlllion FlllI) musl bc e,l"blishcd 

### fur c"oh subjecl emi.<>ion Unl!. TI,e CD also slales lhal "a "30--<Jay Rolling Average Emi""ion Rule" shall l,e delermine,1 

### by calculaling an nrilhmelio average Ill' all hourly emi,sion miLo in Ib:>IMMBlu for lhe cun'enl Operaling Day anJ lhc previous 29 Operaling Duys. An,,'" 

### 30-<l"y Rolling AVC"T"ge Emi<siOLl ROle shall he calculated**fo~each** new Operaling Day_ Each -,O-day Rolhng Average EmisslOn Rate sh,dl include slurlup, shutdown, and Malfunelion 

### p,-nOlJ> wilhin cuch Operating 

### Dayn"_

"Ibid footnole ",.nlber 1, I"",graph (,(" page 20. Il Ibid footnole number 1, P,,,,graph 5, l"ge4. IvIinnkolu PowcrCoopcrulivc, Inc. 3-40 B"m, & MoDonnell

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A**r~eenl** SEGlJ proposed PSD permit has included" uefinilion "fsl:rrtup a, "the period**b~ginning** wllh ignilion and lasling ULllil Ihe c'luipnwnl has reachcd a conlinuou, opcmlmg; level 

### "00 opera/ing**p~rmil** limils"'". Simibrly,,, shuldown is defined as "lhe period**b~ginning** wilh Ihe lowering of "<Juipmem from busc load and lasting unlil 

### fuel is no longer added 10 Ihe hoiler and eomb"sli"n has eea"e,l"". Based on Ik n;fel\-"nee<l definllions ora Slarlup peL'lod und u ,huldown perioo, the ammmt of**lim~** required [or" SEGU's load (boiler Sleam OUlp'" Or generalor eleclrical OUlpul) 10 Increase Ilcyond such minimum .,mmi"uhle opcmtlllg level, ean be considered p'lTl of,wrtup evenL, ifthe SEGU " typically b",,-Iuuded al 

### full load 01' MeR O"lpUL Thi, is Ihe ease with both MRY Sialion SEGlk

51aliul" ofSEGlh may he lnhderl us cold, warm, and hollo accounl ror thc amount ofre.,idual hem remaimng ill lhc buikr "nd ste"m l"rbine equipmenl. The various lypes ofstart, ore depen,knl upon Ihe amounl oflimc lhe SEGU has been out"uf-scrvice (i.e. wilhoulhailer ruel firing or generator megnw"U outpul). Cold .aarlS have 

### been del1ned as slarts arter lhe boilerhas been wilhoUl fllel firing fOl' mOre Ih"n 

### 72 hOIlT', warm ,"'rt$ or" more lhan 

### 8 hours and less than 

### 72 hOllTS, and hot slarl'; are less ihan 

### 8 hours".

Althoul;h lhc definilion ora :;Iarlup ewnl and tile col'responding s!arhlp period IS not required by lhe Consenl Decree, defining slurl-llps is**recomme~ded.** 1"l1i, helps to address !he speoi fjc emission limilllion., during Unit slartups at Milmn R. Young Slation and determine lhe imp,,"l ofsllch operations On 3U-day rolling average 

### No" "mi",ions. ['or Ihc**purl'0;;~** oflhi, 

### NOx BACT analys is,
a Unil Slariup was deJined as Ihe period from inilial fuel combuslion lO lhe poinl in lime when:

• the measured IleallnrullO the boikr on a 6-hour rolling avel'age b,,"i" is greater Ihan Or equ;]l lu 250U m,llion 

### BTU/In- for Unil 

### 1; or

• Ihe amounl oflime reported for rhe longesl individual Unit 1 slartup period dming aclual opemlion belween January 1, 200 I and December] I, 2005 elap.,es, whi"hever occurs l1",r; or

• [liel firing is rli,eonlinued prior to ,ati.,Jying**~ilhcT** previo,Js crilcria.

This 'larhlp definil,on Jor MRY Smliou Uml 1 account, [or "ondi,i01l, where eyclone refraclory malerial._ repbtt,] during boiler overhaols must be cured 

### by**e.~lcnded** low-firinghealing cycle.,>

,. Do,cr1 Rock EnergyCenlcr (A7P04--01) 1-'lOp05CJ Pl;1l Pon"il Condilinn<, page 7. (IJlip:!Iwww.epa_goy/rcgion09/airipelllliLlJ

...orlrock/llJ1<.mliL) J7 Jhin, p<lge 7.

" Applicalion for PrcyenliOIl ofSi£uilicanl I)denora,ion Pelmil fnr Ihc D'Sert Ruck Energy Foollily,

Docnmelll Numl>or 094 17-JG0-250RI, May 20114, page 5-1. MillJlko(a POWeI Cooper"lwe, Inc. BUlm & McDunneJl

### HAC[ Analysis roc MRY Statim' Unll I NOx Emissions NUx !lACT Atlillysis Slody

nnitconlmls arc upgr-aded and mu,t

### be "djusled during**low-lo~d** 

### opemtion, or forboiler feedwaler qualily 10 improve after boiler mainlenance h"s been perfonned Ih"1 "ffccls lhe inside' oflhc Wlllerw"ll und superheated slearn tubc". II also allows for a failcd or inlerruptcd start <equence which Can require consi<!cwbly less Or more time 10 elapsc lhan an averal;c s\flrlup duralion.
Analysis orMRY SlationUnit I opernlion, d"la from 2001 through 2005 revealed:

• ThLTC**"'~'Tc** 

### 60 lolal slartups in Ihc five yearperiod;


# •

• Minimum slartup was 10 hours ror a ··hot" slart li>lIowing a boikrmasler fuel inlerruplion (Vnil "[rip"); Mnxirnum Slartup wilh an exlendcd ramp-up period lmlil full load was reachc-d was 61 hours.



# ,'. '" 

## . Unil] had a SLart_up Ihat began On June 27, 2llO5 Ihatlastcd for 61 hours_ This startup included inilial firing in the 5" hour of6127 (0500 hours being Ihe beginning uribe slartup period), and which endcd "lthe end oflhe ]7'" 

### hour (i.c. al 1800 hours) On June 29", 2005 upon reaching a l;cllc,-awr output of245 MW (gross) rnlher thon a 6_hour average heat inp'" rale ofmore Ihon 2500 million Btu per hour.

TI,ere are cerlnin hoiler operaling conditions thai need lo**exi~1** 

### before Ihe BACfNO" control Icehoiques and teclmologies can 

### be effeclively operated:

1_ The rurnace ga, lernperlllurc in lhe region wbere Hurea reagent solution is lojeoled for SNCR-b-

...

'>ed 

### NOx control musl**b~** 

### belween 1700"F and2JOO"L TIus region is expeeled 10 be in Ihe vicmily oflhe furnace exil, whioh is oommonly defined as eilher lh. horiwnlal plane extending from Ihe furnaee rear waH arch C·nose") 10 Ihc fronl wall o[lhe boiler, Or Ihe vertioal phne from Ihe nOSe up 10 the furna"" roof, upstream oflhe gas mletlo Ihe superhealer lube banks. The gas lempCl"llture (FEGn I"llnl;c in lhis fumace rcbrion is dependenl on boiler heal inpulrale and cleanliness oflhe firesides ofthe [umoee walls, which orrecL, the amoun( ofradiant energy absorbed by lhc wall tubes an<! lransferred 10 Ihe waler within. 2. The numbers ofaclive cyclones and conlinuous coal firing rales musl 

### be enough 10 establish suffioienl:
a. coverage ofmollen slag on !he actively-fired cyelone barrel surfaces and drninage of lhe slag from the bOltom ofthe boiler; and

Bums & 

### McDonnell Miruokola PowerCoopcrdtive, loc.NOx BACT An.lySlS SIUlly BACTAnaly,is for MRY S[",;on Unil 1 NUx**Emi.~"ons**
b. combustion air/low through lhe aclively-fired cyclone:; 10

..llow a pOl1ion\0 

### be diverle<l to Ihe scparated owrlire air sysLem abo"c lhe**amountrequlT~-.J** for idle cyclone cooling and SOI'A noz:-dc cooling. 

# As prevIOuslydiscusscU, [unlace eXli

# n",· gas lemperam",:; (FEGTs) win ne"d 10 be mea,urcd or delermined empirie"lJy during opc",lion oflhe MRY St"lion boile" in order 10 be ahle 10 etleolivdy control 

### NOx emis",on' ming 

### SNCR lechnology_ Th,- 'ksign and opwLlioll oftl,e 

### SNCl{ oy,lcms "t MRYS for CD Pha,e 11 em,,,ions eont, 01 .'],o"ld inclnde fealures Ihat aecolllrnodale cyclone hoiler :;I"rl"ps "Lld ]ow.10"d operat,oLl Wilh "dc"n" or '"dirty" boiler heallronsrc"T sLlrface"
"s ,nOLl n< conditIOns OCCUr Ihlll "re lechnically procll"able, i.e_ w,lhin Ihe SNCR 'yslcm vendor's**recomm~nded** opemllng guidelines, os ",

..dl "s fulT-load con,hlions in orde, 10 mil1lllli7-" No",

Tile amounl and duration nfsusl"inod boiler henl inpLJI required ill eSl"blish lhe operaling condilion:; dcscnT:>ed In item 

### 2 "bove J" more ,liflicu]1 10 1" eci.,ely ,!ctem'ine. Lignitc heal conlenl v"TillbiJity ""d iLlahihly 10 "ccuralely <1clermine Ihe acmal aiTff"cl rolio on cyclone-by-cyelonc b"sis in real-rime, "nd Ihe slaggi"JS lind fouling characlerislics oflhe lignile "sh, came (and are expected l<)**~onlinue** to cause) ,!lflicullie.' Willi Sl"bk eombusIion performance. The minimum nriJlg**r"lc~** ofthe 

### MRY Slalion boile," required to**~lIccessjilT1y** inilillte the effedi\'c operation oflhc SOFA sy"lelll are 'pecifie 10 eac1, i"dividulli bo'ler, aLld a,e nol currently known. Due 10 Slleh Opelaling pr<Jblcms "nd emi,;-,wTI eunlrol limitalions, Ihe abihly 10 dkclively Iimil 

### NOx eml"JrIn' during slarlup periods "nd low·lu"d operalion following implemenlalion ofadvanccd SOFA (CD Pha"e I conlrol) "ndforan SNCR system (CD Ph"sc II conl,ol) is "nccJ1ain_

Bcoause lhe,e Jre expecled 10 be minor short lerm variation' in operaling condition" durin!; slartups where MiLlnkolll hll' not, in**fae~** m"lcTIally ehonged nny oftheir normll] slnrtup oremling prneliccs and crileria, a margin belwcen lhe Jll-day rolling average**"lendY·'~"lte** 

### NOx """",ion rote (which doc, nol include lhe impnct, ofslartups) anu Ihe proposed 30-day roTTing avcrage 

### NOx ellli&sion pennit lim' tlhal includes slartup emi"ions is recommended. 1bi' role considered 'eco!;nized operalion,,1 factor" and equipmenl de"ign" apphcd 10 sleady .'laLe eondilinno wilh suslained output close 10 maximum continuous eapaoity ralings. The recommcnded 30.day Rolling Aver"gc 

### NO, Emi"""ltl Rale pC1"nnl limilation exclu,ling Ihe impact ofsl"rtups lh"1 reneols BACT IllrMillon R, Yo"ng- Slalion Unil I '" shown in lhe lable below.

Mum!."I" Puwcr CO"l"'rmive, Illc. 3_46 

## num" & McDonnellBACT**A".I}~i,** for MRY Sialion Unit t**NO~** Emission'



# -------------- 

# - NOx llACr Analysis Sludy



# --------
-----

.-

## ,.,., TABLE 3-20

- Recommended 

### NOx BACT Control Method and 30-Day Rolling Average 

### NOx Emission Rate LimitWithoul Startups
30-day Rolling Average 

### NOx 

### Unit Pollutant Control Melhod Emission Rate Limit Excluding Startups lib/million Btu) Selective Non-Culalylie 

# , NO, Reduolion with Advanced 0.J60 Sepurated Overfire Air IASOFA)

This recommended BACT 3D-day NOx emission ralC limit is hased upon a hisloric prc-conlrol30- day baseline avCrdgc NO

### xernis<ion rate of0.884 lb/mmBlu for Unil I. The ha.seline emission was delennined from the**30-eonseculiv~** day period with the highest hisloric unitNOx emi"ions rnte reporled lor aotualopcration bctwceo January 1,2001 and December 31. 2005.

A recommendcd 

### BACT 30-day NOx emission rate limit llmt includes !be impaol ofslartup emissions should be suitably highc, soeh lhm opemtion consislonL Wilh lhc lechoological JimiLalion". mnnulaolurer's specifications, and good cngineering and maintenance practices to !be extenl praclicuble fur the MRY Slalion hoiler' would not resulL in an exeeed",ee (violation) ofan enforceable JO-dayroHing; average NO

### x emission permit limit

For MRYS Unit I, the recommcndcd 30-<lay rolling average NOx emission pennit llmil rale mal includes the impaci of"Iurlup' is bascd upon**rccogni~ed** operalional faclors and eqoipmenl designs thai innuc"TIce wheiJler lhe startup emis.'ions resull in highc, 30_day emi""ions compared to normal conlinuous operalion without Or cxcluding such stllrtup peliod,; 

### 1. The uncoilirolled cmi"ion rate (i.e. withuot scparaled OFA or 

### SNCR in oper;ltion) and its variabililY during opemlion Irom a cold, wann. or 

### hO[ slartup up to and mcluding maximum eonlinuous raled oulpul; 2. The opefming oonditions lhallU"e required 

### 10 exist for the selecled NOx

### BACT conlrol techniques to be initiated and be effeclivc; and 

### J. The efTeetiveness 

### ofthesc two panicn]a, control techniques 

### Ifinvoked al 

### kss-!hon"MCR Sleady-sLate operating conditions. 4. The numhcr o[slartups and the,r range oftypical dumlions per 30-day period lime frame.

Butn, & McDo'mell Miaakola PoworCoo[>Crativo, Inc.**~(h** BACTA,,,I}',i., SLuJy R"·i.,,,J 10, 1);:'.000

-----**-~ Th~** **Jun~** D-29, 2005 <Ianup was ehmen [()J' additional evohWlio" a< tho ,(,,[I-up fOf )vJRY SI>llion U"it 

### I.

An ineremenlal odjmlmenl 10 Ihe proposeJ 30-day rolling;**llver~g"** ,Ieadj' -'lale u"it NO., llACT em!"ion rate wilhou! stamLp5 or0.36 IblmmFllu rnr UniIii, recommeLlded for Ihe 30-,lay rolling Jverage 

### NO.• emission permit limiI retiod< "-, detl"",1 nnd arplicd 

### 10 Milton 

### R. Yo""g Sialion. Thi, is >lmum"i,ed in Ihe miJle below.


### TABLE 3-21
- Recommended BACT 3D-Day Rolling Average NOx Emission Rate Limit and Startup Impact 30-day Rolling Average 

### NOx Impact on 3D-day Rolllng Unit Emission Rate Limit Average 

### NOx Emission Rate. Exc:[uding Slartups Limit Due 

### 10 StartLips (Iblmillion BtLl) (Iblmillion BtLl) 

# , 0.J60 

## I 10.041 

### ror ,tJm1r

Thi, rccommeaded adjustment m the IlrOpo,ed 30-da)' rolling average <wJd}'-stJIe NO, nACT emission ,"Ie limiIwilhull! slartups is**b";~d** upon average hi,roric pre-eolllrol NO.\ elllissicll L7LI'" ot·O_766Ibimm[Jlu for ULtil 1**rCjl(]rl~d** fur lhe longe" indi\'id"aIU"it 1 'l:lrILLI' perin,1**dllri\l~** ",Il,"l operation**betwc~n** January I, 200 

### I a"d Deeo",ber .11, 2005. The,e emi,.,in..., uccurrcd**duri,,~,** Ihe 61-hour June 17-29, 2005 ,mITUr for lJl\il I.

. -'t. l'l-hour rnliing**avc,,,.~e** [IA(T NU, emission "He limi! applicd 10 ,Ia""p periud, i, abo ['ecommended for enell 

## orIhe !vlihun 

### R. YOULlg Siniion boilers.
Thi, i, summari,cd in (he**("iJI~** below. 

### TABLE 3-2.2
- Recommended 24-Hour Roiling Average**NO~** 

### Emission Rate limit During Startups
24-hoLir Rolling Avarage 

### NOx Unit Emission Rate Limit DLiring StartLips (lblmillion BtLl) 

# , o.no

Mino,ota r"werCo"pcml;Yc, Ino. 3--18 BUlll' & "101)""0011BACTAnalysis rOT MRY Sullion Unil I NOx. Erni,,-,ion<**NO~** BACT Analy,;sSludy

-

# ..- These emissions occurred during thc 61-hour June 27-29, 2005 startup for Unit 1.
Compliance with Ihe-Ie emission rales would**b~** measured at**th~** stack ofthe**LJni~** verified wilh Continuous Emission Moniloring (CEM) sySlems in aceord"nce wilh Ihcrcfercnce mClhods specified in 40 

### Cr:_R. Part 75, "nd would bc delcrmined on a 

### 30 conseculive Operaling D"y and 24-consecutive hourrolling average basis, respeclively.

A trial demonstration operating period of 18 monlhs ufier Ihe complelion ofConsenIDeoree Phase 

### II NOx emission redoetion system inslanalion commissioning al Millon R. Young Stalion is recommendcd. It is proposed 10 

### allow MinnkOla 10 demonstratc the aclual oontrol systcrn capabilitics oflhc comhined 

### NOx BACTemissions reduction syslcm. Operaling experience during Ihc trial period will:

• confirm steady-slale conlrol perlonnance ofthe eombincd 

### NOx 

### BACT emissions reduclion syslcm;

• allow determinalion oflhe abilily 10 furtkT control Unil slart·up emissions;

• allow the dClermination ofIhe permitted 30-day rolling average

## NOx emission limil including startups, "hutdowns. and malfunclions; and

•**~d<!n:ss** the ,peeifie emission limilalions during Unil slan"ps at Millon 

### R_ Young Slation nnd their impaci on Ihe propo.sed 30-day rolling avcrJgc emi""ion mle limit (without slartup")_

Based upon Ihe .information oblained during the trail pcriod, [inal emission limits Can Ihcn be determined.

ThemeanS Ihal will bc employed 10 minimize emissions dUring slartup will primarilybe ha,ed on operaling procedures, bolh before and. rLer the level ofupper fumace gas temperature, and/or he.1 input rale arc eunsidored sufficienllo slart Ihc 

### NO

### x conrrols and opcr.Jling oonditions are conducive for effeotive emissions reduction. These could be similar 10 Minnkota's cum-'Tlt MRYS practice" or wuld be differenl, depending "pon lhe c.pahiljli"" ofIhe 

### NOx controls and theirimpacls on Unil**OP~T'lions.**

Bums & McDonnell Minnkola Powcr Coop<:ralivc, Inc,NOx BACrAnalysIs Smdy

Referenc"s: [IACT Anoly,is for MRY S'aLion Unlll NOx Emissions

I. III the United Statcs Dislrict Courll'or The Di,trict OfNorlh Dakola, United SLales

# or Amcric" ,md Slate Of North U"kol:t, Plaintiff" v. M,,'T\koLa l'olNcr Coopcwli"c,lnc. ami SqU"TI: Bulle: Eleenic Coopemllve, Defend"nl", CIvil Action No.I:06-CV-034.
2. EPA New Sourcc Rev;ew Workshop Manunl, Prevenlion ofSijlnifLcJlll Delcr;",aIJon aod Nonall"inmCul Area Pernullillg, Draft Oclobcr 1990 (The uNSK Munuol").
J. EPA Docket OAR-Z002·0076-0L\46**T~cl",icol** SUPP0l1 D(JCumem 

### for HART NOx Limits lor Jokelne Generaliog Units Excel Spreadsheel 6/1 512005, posleu on lheir wcb,ilc: [rom EDOCKET at hIlI';

### IIuoekCI.epo.govlcdkJlubl

### dolEDKSto[[]IcmDclui

### IV,ew'Iob 

### j colId**~O** 9000

### 7<14SO84562b; Ihi.' i.' ae..,oeioled wilh EPA Acid Rain hOb'rum C1eaLl Air**M;JTk~t"** Divi"ioll, Tecll"ical Supporl Ducume",

- Melhodology I'or Developing BART NO, l'rc>umplivc Linlil>, June 15, 2005,OAR-2002_0076_0445_
4. EPA Office 

### ofAir Quality Plarmmt and Siandards (OAQPSj puhlicat;on EPAI,1521ll-02-00I, Scclion 4.2, NOx Controls

- NOx l'osl-Combll"lion, Chapter 1 - SelecliveNun-C"I"lytie Redllcliun, d"leu Oclobcr 2000, posted allheir webSIte: hltp,llwww.epa.gov!ttn!cJtcldLrlfcs4- 2chl.pdf**MinnkO~1l'Owcr** CO"l'c"TIIl1vc, 1m;. 3·50 Bum, & McDonnell

## ,.,-, APPENDIX A Technical Feasibility Assessment Details for NOx Control Technologies (A1) U.S. Coal Cyclone NOx Reduction Projects Summary With Retrofit NOx Control Projects' Technical literature Summary (A2)AI'PENDIXAI Toohnical FClISibility Assessmcnl**Dda~,** fOI" NOx Conlrol Technologies NOx DACTAnalysis**Sru~y**



# A.1 A.1.1 Technical Feasibility Assessment of NOx Control Alternatives Pre-Combustion Fuel TreatmenUSwitching

,

## ... Fuel swilehing can be a viable melhod of

### NOxemission**rc~uclion** in certain ,ilWllions. Olkn, coal combuslion facililies are construcled 10 lake maximum advanlage oflhe particularcombuslion charJclcnslics ofa specific fllel. 

### In lhe Case ofMRY SMion, the Unit 

### I and 2 boilers were designed and constructed ,,.,-cifieally lor firing North Dakota lignile, which has a fuel higher healing value (Blullb) approximalely 20% lower ,han typical Powder River fiasin 

### (l'RB) cool. 

### A cyclone-fired boiler (Oltertail's Big Slone Unil 

### I) Iha, is similar in gcometry and steam geoemlion design lo MRY Slal10n Unil2 fires 

### PRR coal. Based on a comparison ofavailable emission data belween Big Stone Unil 

### 1 amI MR Young Unil2, lhere is no expecled reduclion in baseline G.e. uncnnlrolled) NOx emissions from swilching 10 1'ItB from lignile al Milton R_ Ynung Slalion.

Conwrsion o[Millou 

### R. Young Sialion Unil 

### I boiler 

### 10 fire 

### PRE coal is technically possible. 

### II is expecleulhal major planl modificalions will be required. Rail service is nol prcscnlly inslalled at lhis silc, 

### so the addilional opcmlional and capilal costs to bring in Iargc 'luanlilie., ofPRE cnal will be "ignificanL Invesligaliou of!hc sp"Cifie source, dl"rnnCe, and cosLs for supplying nccessary qunntilie" of

### PRB coal via rail or lrocks to 

### M_R. Young slal,nn has nOI hecn perfonmiL With zero baselineNOx cmisslOns reduction c"pecled li·om application offuel swilching, lhis ahernalive will not 

### be economically compelillVe Wilh olher NO

### x conlrol ledmologie< lhal offerbelter resulls 

### ror a much lower combinalion of capilal and operalional eosLs. Although fuel Swilching is technically**fea~ible,** il has notheen consldered further as an effecllve NO" emissions conlrol oplion forMRY Stalion Unil 

### 1 boiler.


### A.1.2 Combustion Controls Combustion conlrols comprise !he mosl num,.nus calcgory ofNOx emission rcuuclion lc-chnoJogies. These lechniques cmploy methods lhal reduce lhe amounl ofNO

### x emissions crealed in [he combuslion
zone oflhe boilerprior 10 e>JJausling lhc /lue gases from the furnace (up>;ITcam ofthe eonvccliveheat trausfer zones). The.e coutrols resull in fcwer emissions 10 almnsphere or lhal may reqnire subsequenl rccluClion from addiliun"l applicahle comlmslion andlor posl--combuslion lechnique,.

As lhe boiler>; in queslion were desigoed for firing North Dakola ligoile fuel, lhey wcre furnished wilh suilably-sized furnaces "nu bmiled hack-end economi7.er heal transfer sort,ecs upstream ofIhe air prehcalCTs. This provides high lemperalure air 

### 10 aid [he evaporalLon ofexcess mniSlure from lhe crushed coal partides in lhe pre-comhuslion drying systems, and long residence times lor solid and gaSC(lUS fuel
MmnJrola Power Cooperalive, Ino. At· t Bums & McDonnellNOx BIICTAn,ly,i,**Stu~y** APPENmXIII TechnicalF,-<",biJity A''''>SIUenl DoLail, for NO. Conlrol Tcchnologio,
parlicles 10 bum es.,ent'ally to colltl'letioLll'rior!o kuving Ihc lilmace,. The laller fe"-tnre i,**~'"P"eiajJy** advanlageon., for applying "nrio"s rorms "reombuslion moJili,'oti"ns which are cond<Jcivc in rcducJng 

### NO, emission.'.


### A.1.2.1 Basic Combustion Improvements Combllslion improvemenls a, e commonly·:>pplicd Ic"hm'l"'" wo,ch may produce mode:;! im:n-mental NO

### x emi.""on, rc<1lJCI10n,_ In Ih"iT**mO~1** basic fonn. these lypically pwv,d" improvcmcnls to com],uSI'OJl**~ir** now dislribu('on, mC<lsun'm"nl, "nd prcssure. logclher wilh Iilel now mca,uremC'TI1 and metering, [0 promole consistenl combnstion**~eJi("** mane" by Imming rud w,lh more accuracy ill mainl<lining a desired fUel/aJr ralio.

Thc," improvcm''TIl>; m"y lIUOW, or bc combined with. the praelice or,,'vcral olhcr

### NO" control lechniqucs, SqJaTIllcu ovcrlirc mr (Jiscll3Sed helow), "',lh or wilholll "low cxec,," "ir" (LEA), bLJTTJcr, out-<If-service**(BOO~)** and h,"sed**firin~** (IW) opcrnlicm ofIhe cyclone" e"use a decreasc in lhc ralio of comhustlon all' to iilel supplied to lhe cyd"n"" (burners), Ihlls reJucing the amount oflhermal NOx**"J11iSoion~** produccr! J"ring "QmhuSlion, Thc "mounl 

### ofp"lenli"1 

### NOx em,,,ion rctluelioLl achiev.hlc from lhese b",;" lechnique, is highly-uependenl on the specitic IYpe offiring, fud. "nd condilions which apply 10 lhe b"iler(,) heing, reviewed.
M"king lif,",ile ,Irying 'yslem air aJjuslmenl' and adding improvements 10 lhc boiler comlmSl'un controls anJ reJncing combuslion "ir inplll" have "Iready reduced uncontrolled 

### NOx emi",ions al Milton 

### R. Young**~Ialion** boilers "pproxml"lely 10%. l'uI'lhcr inc"'me",,,l ,mprovements flOm add,lion,,1 eOlllhu'liorl conl",l, Ihal allow operalion with mouesl mnounls orcyclone oir .,raging, "imilar 10 Ihe**err~cl** or" sepor"ted overfirc a" "y<lem, OrC po,;,iblc, Incremenl"l 

### NO" lwis,;on, reduclions are expecletl from slll'h impr(lvcTllenl, bClng 'ncorpowle"l inlo "nother fea.<lble "ltemalivc,**~uch** '" scpar::Lled overfirc air. Tnis altenmlive W"S not considered"s a srand_alonc uplion ror odr!ilional NO" reduclion

.. 1Millon R. Young StatiOLl for lhe Uni! I hoiler.



### A.1.2.2 Low 

### NO

### x Burners (LNB) Low 

### NO" bllmcn; (LNBs) 

# orvoriou, <!c,i,,'Tls have heen commonly applieu 10 pulveri7.ed coal-fireJ ulility and mduslri"J boilers for morc than le'TI years. llowcwr,**lh~y nr~**  not i,,"lalled on cyclonc"fire,,1 GOller.<. Thi" IN,Imology is ,Il**r~a"hI~** On cyclone boilers', and WliS eliminale,1 from consi,lcrnl,on for .dd'llO"al 

### NOxrcduclion atMillO" 

### R. YolJng Sl"licm Unil I's hoiler.

[lum, & McDunndl Al-2 MinnkOla Power C"opcr,Uiw. IllcAPPENDIX Al TochnioaJ**F~as.ibi~ty** A""ossmem Detail, fOT NOx Control Tecllnnlngic'


### A 1.2.3 Separated Overfire Air (SOFA) NOx BAG[ An.lysis Sludy

Sepnrated overlire air(SOFA) is a combustion-related NOx cmission rcduclion technology frequentlyapplied with and without lowNOxburners to utility .nd indmtri.1 boilers for more lhan 

### twenty live years_ Separated Overfire Air (SOFA) is an air-smging NOx emission reduclion combustion teclmiquc that is typicallybased on withholding 15 to 20 perccnt oflbe lotal combustion**~ir** conventionally supplied to tl,e liring wnc. Thc diverted combustion air is then injected in the uppcr [umao., where combustion is complded_ For typical cyclone coal-fired boilers, th,s invotves diverting approxirlliltely 20 percent ofthe secondary combustion air, forcing lhe cyclones to ope,"te fuel_rich. Starved-air combuSlion causes fewer NOx emissions to bcproduced.

At k-"Sllhirty nine existing cyclone-fired boiler" firing eastern biluminous, midwestern bituminous, and weslem subbituminous ("Powder River Basinn ) coals in unil' ranging in size from 

### 50 to 

### I 150MW, have been retrofillcd with cOUllllen:ial SOfA since 1999. A sumrllilry ofscvc,-al ofthe first SOFA (amI rcbum) retmfits to cyclone-fired boilers is described m published tcchnic.1 papers'·'. Cyclone boilerrctrofit SOFA installations <ITC included 

### in the EPA's BART lechnical support dooument' and listed later,in Appendix A2.

A hasic form o[scpa,-ated overfirc air (SOFA) can be applicd and**in.s~Jllcd** on MRY StationUnits 1. Therc are polenlial irnpacIS and limitations uniq\lc 10 'he firing or-Nortb Dakola lignite in cyclone-fired boikrs that should be recognized as part ofthis emlSs,on reduction technology application.
Kcy a.,pects ofsuccessfully applying nnd operaling a separatex! overfire "ir system un a cyclonc-fired boilcr are the ability 10:

• Accurately measure the 

### fuel heat input r"tc (BnJs) and combuslion air inpul' On a real-time, individual cyclOne 11Y cyelone basis, to allow the ability to determine and control the dcsired air/fuel mIlO, especially when "starved air" (i.e. substoichiomelric) combustion conditions arerequired_

• Mainlain adequate molten coal ash (sl",,) formalion and now within the barrels and slag (ar-'_

The dcgree 

### to which the cyclone furnaces can bc operated with less than lheoretical (SUbSloichiometric) combustion .ir directly contributes 

### to less NO

### x formation and further in_furnace emission n:duction bUI also risks solidifioation ofthe mohcn coal ash. 

### In the case ofMRY Slation Unitt boiler, cyclone combmlion must be sufIicicnlly air-staged 10 n:ducc

### NOx emissions while releasing enough he;)t to**con~nuc** to melLlhe fuel ash so lhat it 110ws effectively within and from the cyclonc burners.

Minnko13 PowerCoopcralivt:. h,e, AI_3 Burns & McDonnellNOx DACrAnalysi, Study APPENDJXAI Teclmio.l Feasibility 1\.,,,""'""1 Deloils forNUx ConlrolTeohnologic,

In lhe oase ofMIlY Stalion boilers, lhere i, a sigllllJoanl ml100nl ofvariahility inlhc eornhu,'lible Jnd w'h componenls ofNorth Dakota Iignile ""ppJied from the cll'Tenl mine near Center, NO. Aoaly"is ofseve,.."l [mndr",l cu,,1 feed san'pk> L,ken "irnullaneouslyji'om mulliple cyclones ofMRY Station Unil 2's lJOilcr ITve.led that ll,o rrr"ximum dilT"ren[ial or [l,e ligmle healing val",," from cyclone-to,cyclone w"s

### ju"
over 12% ofIhe average healing value of"11 lhe sampk". AssUilling all opcruling case ooctJrred wkrc Ihe maximum cydone-lo-cydunc differerltJn1 he;Jling**valu~** W;JS fur lwo cyclone" m Ihe uppo"ile enu, 0r' Ihe fuel he;JI eunlent**rang~,** Ihc'" would be" plus Of rnin,,> 6%**vari~lion** in f"ellll'''1 contenl fur**eid'~r** uf nl<' individual cyclones frum the**oV~nill** "verage. I[ Ihc ues" ed**"v~rng~** cyclone**"ir/fu~1** (sluichio",clrie) mlio wa, 0.95 when operaling wilh alr-s[Jged cyclones a""ooi_[cu wilh separaIed ovcrr,rc "ir, and Ihe amouLll of,ccQnd"I)' eomhustion air 10**~aoh eydon~**  wa, "'1",,1,**lh~rc** would k a**"IOlchlOm~lrie** rallo or Jpp,oxlTnalcly 1,01 in one cyclone and a ,'IO,chlOmetfic ralio "round 0.89 '"**anolhcreycJon~** a[ lhe Same lim"

..fhe modes(]y air-'l"ged**cydon~** would pI**odu,,~** higher lhan averar.c NOx CTJ1lssioJls.**'j"h~** deeply sl"geu**eyclon~** would produoe**l~",** !han**Jver~g~** NOx elJll"",ons alld pOlenlially in,ulliciL"Il1 amounls of heal**releJs~,** and raise Ihe ri.,k of,0Ji<lifying the fuel ash "0 lhal il accllmllbles will,in lhc cyclone**ball'~L** Thi, could T(,,,rll in firing**~u~ili"'y fu~1**  oil in lhc**de~ply-Sl"geu** cyclone or taki"g Ihc boiler**o"l-of~'~r"ie<'** 10 remove lhe pluggnr.c. Neilher**ofthe,,~** eondllionl- lS**,lcsirabl~ l,eo~u,",**  llwy [(·,,,11 in low<:r cmi.",om**r~moval** pericrmanee ,mu**high~r** opcT"ling cose,. Thus.**du~** 10**lh~** variabilily ofthe fuel heat**conle~t ~nd**  the complex beh_vior o[**li~ni** le aoh when**~xro,e<llo** hJgh kmpcn'lures, lhe exlent ofaTr-slagrng and thus Ihe lewl ofNOx control in MRY Stalion hoikTS is**~xl,"el",llo b~** **1J10d~st** wl,ile firing lignitc coals.

ln order 10 pOle[\linTly**nchi~ve** lower NOx emi,<sion mles w,th morlcotly "ir-slJged cmnbtlslion [or MRY Slallon boiler", addillOnal comhuslion imp, ovelllClIls can be 1l1'I"lled.**On~** potenlial irnpro"ernc"JJl is 10**LJnplCrll~"1** " unique form ofSOFA for Norih Dakola-lignile-fired**cydon~** bOlle". This includes relocaled lib'llile doying syslem venl pOrlS. This will bc rderred [0 "-, ·'Advanced SOFA" (ASOFA). Tl'<:rc arc several de"ib'll challenge$**anlieipal~d** for impkmenting the advanced versioLl (wi[h Ihe descrJl>ed porl rcloealions) ofseparated OFA. These**ar~** khcve,1 10 be**solva!>I~.**
nOlh lorn}>**ofs"parat~d** ovcrfin: air as a COmbllslion-rd"IGtl NO, oonlmll"chniqllc are considered**fc-asihl~** lor apl'li""llOl1l0 Millon R. Young Stalion cyclone bOlkr", Since lhe advanced SOFA is**lh~** highcsl-pcr[omling I'lnn oflhi, leclmology, only Ihis ASOFA version ofthe allcmJlive**w~o co",id~rcd**  [or audilional NOx**r~dlJclion** al Milton 

### R. Young SI"lion boilers.

MlIlnkola**Pow~r** Cnore",live, Inc,APPENDIX 

### Al Technical F"",ibiJi,yA""e",mcnl Del.ils [orNOx 

### Control Tcchnologies



# ------------ NOx BACI'Analysis Study

.,'-' 

### Another fonn ofseparated overfire air being markcled commercially is "Rolaling Opposed Fire Air" (ROFA)_ Forulility applicalions in Ihe United Siales, this ha' onlyheen applied 

### to pulverized coal-fired boilers, prim,nily langenlially-fired uni",'

_ 11 

### is diffcrenl limn basic SOFA in thai il 

### includes a hoi air booster fan, and injects Ihe overfire air in an offset rashion 

### from opposite sides Oflhc furnace al high**vdocili~"** 

### with mulli-ponnOZl'Jes localed at high eh:valions relalive lo Ihe lOpburnerrow.**Th~** 

### vendor**(Mobole~** 

### USA) claims ROFAmaximiz

..:s**air-~Laged** 

### in-furnace combu.'lion NOxreduclion while minimizing negativc impacts on carbon monoxide and flyash unburncd carbon.

While Lhis varialion ofseparaled overlire air could pOlentially bc applicable to cyclone boilers, i1 has nol been markeled 10 

### Serve such applications. Because cyclone boilers do not reqnire Ihe addi1i,!n ofhot air booster lims for 

### SOFA, Ihis technique 

### i, nol distitlct enough from basic SOFA from fimclLonal andair_ staged cyclone NO

### xreduction performance slandpoinls 10**W~mltlt** 

### individual cOtlsideration. ROfA ledmoJogy lacks demonslratd cyelone---lired boiler experience,**~nd** 

### thus was oonsidered infeasible and not included in !he conlrol effeolivencss and cost--effectivene'" sections ofIhe main report.


### '-A.1.2.4 O:Kygen-Enhanced Combustion

A supplier ofliquid oxygen (Praxsir) 

### has developed a meLhod ofreplacing somC ofIhe combuslion air -supplled lo 

### Ihe burnen; wilh pure oxygen. Combuslion aLr, which i' normally input Ihrough (he sc"Condary

'air system duclwork downslream 01" the forced draft (FD) fun lind air healer, is supplemenled wilh pure oxygen dircClly injected inlo thc burners_ Oxygen-enhanced combu,tion (OEC) can reduce boilerNOx 

### emissions =ulling from .• Ihcrmal NOx", a reaction ofIhe nitrogc"ll in the combuslion air admiHed to the burners wilh tho available oxygen in Ihe air in lhe name or peak lempcratllre region, oflhe fuel combuslion process. The use 01" pure oxygen instead ofain-educes the availability ofnilrogen from Iho air 10 

### bo oxidized in Ihe high Icmpern1ure regions. Ihusreducing rormation oflhennal NOx

_ 

### This lechnique has only been demonslrmcd in a boilerwith pulverized fuel burners firing 

### biluminous coal'_

The lack ofadequate experic"llcc On any cyclone-fired coal-burningboiler, on a tcmpo""ry demonstralion


### , orpermanenl full"scalc basis, and for a eoal_fired faeil ity ofIhis size, precludes coosideration ofoxygen· enhanced combuslion atMRY Sialion Unit l's boilcr. This is deemed to be infeasible technology at lhis localion allhc present limc.

MinnkOla Power Coop"rolivo, Inc_ BunlS & 

### McDonncHNO. [lAC!' Analysis Sn1dy APPENmx Al T""hnical Fo.,ihilily Assessment Derails fot NO. COnlIn! Technologies


### A.1.2.5 Flue Gas Recirculation Flue gJS recircul.tion (FGR) h;," bcm commonly applied to coal-flred boiler,. primarily lo inject into lhe lower furnace.jmt ,h'lVe tlie b"m","", '''Wlic",l from Ihc boiler', economizcr fl"e gas outlel YJa n bol gas homTer lim. Thi, modifies the amounl and temperatme ofhOl fumnec ga, eilher in lhe lowlT-middle Or "ppcr f\lmoce ond convecTion heallransler ZOnes. 

### As Ihis flue gos lypically 

### h"s an oxygen conle"l ;lrolmd 2-5%, II limit" lhe avnilabilily ofoxygen 1Il a Illgh lemperatu,.e, l'O."il>ly liJel_ric1, lower f"maee zone. Flu,' gas U'CITCulJtlOn for NOx conlrol i< mO.'t oommonly upplicd wilh gascoos or lJ'IlIid fossilliJcb III rcduec the high Iemperalores w],ioh OOllverl nilrogen inlhe eombuslion air 10 nilrogen oxides. No examplcs ofusing or in'lalling FGR on cyeJone-fired boiler.' s"iclly 10,. NOx**e"'L~,inll'** c,mlwl we, e lound in uvailable technicolliternture.
}'or MRY Slolion Unit I 's hOLler, I'GR was origin.lly supplied from lhc oullet ofLhc induced d"'fL f;ms, but has .,LLlce !leen disconliTlue,] nnd removed. Sinec it i" llol operntionJI on Unit I, and Therefore does not "ITeot thc polcnlinl pCTform"ncc ofocpJITIted overfire Jlr (in an '"advanced" li)l'ln), il would not he cxpecl,·,1 10 ""luGC NO" cmissions ifrelll,lalled alone or Ln cocllu;"nli(lTl WiTh 501'A. Allhough FGR i, technically feoSlble, Ll bas Llol heen com;dere,l further US"n cff,-cllYe 

### NO. cmi,,;,ms control opIion for MltY Sralion Unit I 's boilCr.



### A.1.2.6 Water/Steam Injection (Combustion Tempering) When npplicd 10 old.T g"J'-fircd am! oil-fired ulility ond indus"i"l boiler.', WalCr .nd/or ,tc;lm injection adds**m(l;"ILlr~** i"lo Ihc low.T furn;lcc, GOnClIlTent wilh or near (10 lhe .,ide orshghlly ab<>,'c) lhe burner" supplieJ from Ihe boiler'" trealed feedwaler 01' am"liary slea", sy"lcm" via" mcl<Ting-pllmp or valve. "lbeIe has hee" sornc li",ilC,llc,ling "fwaler injcelion for NO" emLssions collIrol on ""lural ga,-fired and coal·fired cyclone**h"l1cn;~'.** I'or ""ul-{i[(·J cyeJones, Ihis technique is mosl elTecli\'e On hoilcrs bllming hil"",in(lus co"l; howcver, il has nor been pemlanenlly inslalled and co[\linuouoly "pcr"ted in "'ell appILcaILon.,. Suocessfull(>ng-term 0l,erot;on llfwmCr in]celion would 

### be difficull for IlgnJte-lircd cyclone hoiler:s, due to the high moi,ture Icvcls in lhe coal and Ihe need 10 Ieadily ignile ,"d s"'lain slable eOlnhu<lio" a"d mohcn slag fonnaiion III Ihe eyclone fiunaee". For lhese reason" waler/sIC"", injection. is conSIdEred lechmcally infeasible 

### for NO" conlrol application al Millon 

### 1<. Young**~IJlion.**

BUlII' & McDonnell A 1_(, Mumkula Power Cool"'Ialivc, IncAPPENDIX 

### Al Techmcal Fca'ihHil)'As,",,,mcnlDclail' for NOx 

### Control Technologic.,


### A.1.2.7 Fuel Reburn NOx BACfAnalysi, Study

Anolher comhustion ledmology lhat may be applicable 10 conlrol

### NOx 

### emission" from the Milton 

### R. Young Stalion unils is lilel rebum_ 

### In a similar mUnner lhat OVerfire air diverts n 

### portion ofthe combuolion air inpul 10 Ihc main firing 71>ne, lhe rebumingproccss iLwnlves snpplying a portion oflhc fuel heal inpul 10 lhe boiler al a highLTelevation in lhe furnace_ 'Ibis crcales**~n** 

### upper furnace atmosphere where the rebum fuel's combUSlion produot. causes somc ofIhe 

### NOx fnrmed in thc main burner cOmbuSlion**~nne** 

### and reburn zonC 10 bc convened into molecularnilrogcn. Depending on the amount of reburn fuel uddcd and the amounl ofoxygcn aV;lilable in ille furnace gascs 10 

### combine wllh the reburn fuel inlroduced. addilionul combustinn air maybe supplie<l uS 

### supplemental nl 

### overfire air. Downslrcam ofIhe air injeclion e1evalion, the inlenlion is to complele the reaction ofany remaining carbon monoxide (CO) 10 earbnn dioxide (Co,), plus reduce lhe amount ofeombuslible mnller remaining 

### in lhe entrained 

### flym;h.

The most commOn fOrms ofrehum lechnology applied to 

### utility powerpbnt boilers nre:**·~6'·** -. - -

### PiiN'eri:iooor-rilici'oi'iiztd coo:rrehuh'-(1)Clt"or**MiCR);-~n;j** 

### - -- -- .. -- -. ---------------


## • Gas rcbum (GR)_

Pulvcrized coal**reburnin~** 

### and microni?.ed cnal reburning havc been applied to pulverized coal and -cyclone-firedboilers_ 

### NO" reducti,," cffiniCllnies of50 10 60 pelnenl have been demonstraled on ea,lern

biluminous coal and mldwestern bituminous and Powder River BJSin (pRB) western subbituminous coal. while supplying up 10 approximately 20-30% ofthe boiler's Lolal fuel heal inpullo the reburn ?one7
,,_

For ulility powerplanl boikTapplieaLions, natural gas has been utilized as rehum fuel 

### most onen, demonstrated in two basic approacbes;

• C.onvenlional**~us** 

### reburn (CGR); and

• Fuel_lean gas rebum (FLGRT"')_

Eilhcrnatural gas or pulverized coal (lignile) can be used as lhe rehum fuel. A sufficient quanlily of natural gas is nOl eurrenlly availablc al lhe Millon R_ Young Sl:llion planl sileo Supplying enough natural gas Lo provide 6 10 25% ofLl'e toial heal input lO cilher Or bOlh boilers al MRY Station is expeeled 10 bc lc-cbnicuTly feasihle, although transport pipeline inslallalion capilal coslS, ami eurrenl and predicled unit nmural gas eos!s and operaling economics, are likely 10 he unfavorable_

Minnkola Power Coopenllive, lnc_ !lurn' & 

### McDonodlNOx IJAlTAoolysls Sludy APPENDIX A] Tcchmc"l Fc.,ihili'Y Assessrnenll>tlaib for NUx ControlTechnologle,

-------- VarlO"'; forms offuel I ehumlng hnvc Ixen Je1l1onstraled and operaled roullnely on cyclone boilers for NO

### x emission conLrols_ This has been applied 10 unjl.S Jiring**c~slem** bituminous coal, and we3lern .,ubhiwminous 

### or I'RIJ/biluminous eo<1I blendR, using pulverizeu ormicronized eo"l ornalural gas as Ihe 1I10s1 COlnnLOO rcbllm fucL ReblU "ing lilr NOx cmisoions reductJon has nnl been**deTnOIl~lrJ** l(oJ on a unit filing high moislure, low ileal conlon1 North Dakola Ilgnile_**Pulv~riz~d/m,~roniz,,<l** co"l, "long Wilh conventJon"1 an,l fuel Jeau g", reburn**ted",ologie~,** "f{' dlscussed below_



### A.1.2.7.1 Coal 

### Reburn 10 Lhe cusc ofapplYlllg cooveoliollal e();JI rcburn 10 cyclone boiler., the exisling**~l"'lones** ore Sllpplied wllh the majority ot-rhe 

### Iud, with <,Iher nalural gas or**I'ulveri~c~l** co"l (ligllile) used as Ihe rehum r,,,:] ,uch Ihat the 100al heaL I"pullo lhe boiler is eRsenlially the same 

### uS wilhoul fuel rebum_ Separalod 

### OFA ports are localed abllvc lhc rcb1l1l1 fuel injection secl,on orIhe f,<mace. TheRe SOl'A POri, pruvidc .mflicienL oxygen in a convenlional fuel rehum ill"l"llHlion 10 complele Lhe cornbmlion procc" thai begi", in Lhe m"in combustion zOl\e 011<1 i, ,upplcmclllcd in the ",burn and b,rn](}ul zones. This is shown ,chemalically for a pulverized CO" 1rcburn applicalion 01\ "cyolone--fir<.,j boiler wilh SOl'A In Figure A.ILFil::ure 

### A.l-l J'uh-erizcd Coni 

### Rellllrn**Appli~"lion** on

### C~'ololle Boiler Wilh Ovtrfirc Air'

- " 

# --\

\ BOILEll 

# """"-T

, BURNOUT 

# i

..

lONE ELECTROSTATIC 

# , cc PRECIPITATOR 

# I (
" 

# F" - C**REBUR~** 

### ( AIR

### E~ ZONE 

# V PREI1EATER 

### L
" 

# -**S~C<lNDAR}---/** J 

# . COAL STAG

- 

# - VVV



# - 

# '"

- 

# lJj '---'


# --- 

# . . - :_;:::, • PRIMARY 

# '-'- ' ". AI" {'



# - - 

# - -----,



# - -

# -~~·~~~~~f -- 

# ,;J CYCLONE BURNF.R DRY WASTE TO DISPOSAL

### _~JQLTEN SlAG**~'"** COMBUSTJON ZONE

WATER
--- OVF1FIRE 

# "" COAt REBURt"'N BURNE;R$ 

# '" PULVERIZED COAL

SLAG TO DISPOSAL

Burm &. McDonnell A 1-8 Minnkolo Power Coopcr"livc, Inc.APPENDIX AI Technical Fc""ibil;ty AssessmeJlt Delll;J, [orNOK Conlrol Technologie, NOK BACfAnalysi, Smdy

ltllhe Uniled Siales, pulverized coal rcbuming and micronized coal rebuming techniques for ulilily powerpbnlNOx emissions re<luclion have been applied on a very limilcd full-sca]e, full-Lime basis 10 cyclone-fired boilcTIl in field demonstralion le,ls and longer-Ierm demonstralion opcntlion, respeclively. There 

### h"ve been only two known pulve,i.fi'{i or micronized coal rebum msTallations in !he Unilccl SlalcS

on cyclone boilers, one On a uLility boiler in Wisl."(lnsin, and one On a small industri"l_sizc cyclone boiler in Ncw York sLale"'·"''''''·''·''·''. NOx emi,sions reduclion efficiencics of57 percent h"vc bCI."Tl demons 1mled on CYclone boilers firing "asLem hituminous coal. ormidwcslcrn biruminous and Pow<ler RiverBasin 

### (pRB) western &ubbituminous coals while supplying up 10 approximalely 20-30% ofihe boiler'& total fuel heal inpuL to lhe rebum zone. Wilh Ihe exception ofthe U.S. Departmenl ofEnergy's (DOE) Clean Coal Tc"Chnology Program demonstration projecls""', nO known cOinmerc,ally-avC11able coal rebum syslems have been inslllllcd and areroulinely opernled on cycloneboilers in 

### the Unilccl States 10 date. The DOE-COP projects foccoal rcbum applied 10 cycloneboilers are dc>cribedbelow.

···..P!,lveri"ed. coal rebuming for NOx emissionsrecluclion-'n a.cyclone-firedboiler!Nlls dc;nonslraled on lhe 110 MW Nelson Dewey Unit 2 for Wiscoosin Power & l.ighl in 1991-1992. Reburn fuel prepHm\ion and handling, rcbum burners wilh fluc gas recirculalion, oncl a -Se[llilllled overfirc air system were addecl. Coal reb.urn lesls were eondncred on this lIJlil while firing biluminous and PRll coals. NO" emis.sion control dlieieJ\cie.' of50 to 60 pCTel.lll, with reduclions from 0.75--0.83 Ib/rnmBllI haselines 10 around 0.)8 IblmmBtu, bul as low as 0.29 

### lO 0.32 IblonmBtu, with 

### PRE coal al full load wilh approximately 25-30% ofthe lotal fuel heat inpul from rcbum fuel were demonstraled.9,11,1I The rcbum syslem is no longer operaled on Nelson Dewey Unil2.

Micronized coal reburning has been demonstrale<! in 1997-1998, and continues to operale year-round on a sJII:lH indu'lrial cyclone boiler (400,000 lblhr sleam outpul, 50 MW gross equivak"Ill) lor Easlman Kodak Compauy at thcir Kodak 

### Park raeility in Roche&ter, 

### NY. Thi, unit (Boiler #15) achieves a NO

### x reduclion eflicil."Tley orapproximalely 57 percent on eastern bitumitlons coal, involving limited oyelonc air-staging (cyclones believed 10 

### be ,lighlly above 0% exce.,s air) and 

### amodesT amounl ofov"rlirc air injeelion clownsirearn oJ!hc micronized reburn fuel input nozzles. ApPrOximately 17% oflhe boiler's 10lal ruel heal input is tyl'icaHy supplied 10 the reburn zone. This coal 'ehurn syslem conlinues to operate roulinely althis facilily. This inslallDtion i& reported \0 use a FullerMicroMill 10produce micronized coal wilh 80% passing Ihrough a 325 mesh screen'···u.

MionkotaPo""" Cooperalive, Inc, AI-9 Borns & McDonnellNOx HACrATIolysi' Study APPENDIX AI TeclmicoI Foasibilily A"c",mcnl Dolail., 

### rorNOx ConTIol 

### T""hnolegio'
]fa coal rcbum ,yslcm w"s uppli"d 10 MRY**Sla~on** boilers, Ihc cxi"ling; cyclones would be .,upplied w,lh Ihc majorily oflhe fuel in Ihe Conn ofcm,hed coal, and the halance offuel would 

### be supplied 10 apair of ,lcd,c"lcd pulverizcr>; 10 fl'Cd Ihe rehurn injectioLl p0l1" such thallhe lolal beat inpnl10 Ihe boiJcT is essenlially Ihe .'arne a, WiIboul fud r"bum. In a convcnllOn"1 fud rebum insl"ll"I,on, UFA port' locale,]**abo~c** Ihc rcbum ""clion ofIhe furnace prov,de ,ufficiem oxyge" 10 complele Ihe C(lTnbmlion proo"" thai hegin., in Ihe main cornlm,tion ZOnC oml '" "Jpplemcnlod in the rebum und bumoul zones.

Similar 10 Ihe "pplie"lion of,ep"mled ove, Ilre air,**~lere** are polential impacl, and lim;IUlion" unique 10 Ihe liring ofNOlth Dakota jignile in cyclone_fired hoikn; u,al ,hould be rt:eOb'J1izcd as pari ofIhis emi"ion reduebon teehnology applicalion. 

# A"" rcbllm f"d,**hgnil~ i~**  expecled 10 behave approprial<:ly upon inlroduclion in the lower middle furn"cc 10 help**reduo~** NO

### x emissions. TI,e concern, are ihallhe diversion of" sib'J11lie"nl amount ofheat inpullrom Ihe cyclone barrels 10 u,e as a WlIree ofrebllrn fuel in the fonn ofpulverized or micronized lignile may reduce eyclone lemperalures C"Ilough 10 inhibil sJag Iormalion and now, e,pecially a, boilcr lo.d i, reduced. AJr·Slaging lhe eycJones with Ihe use of ,ep"raled owrfire air 10 furlher tOmpk"Illtnt combustion NOx rcduclion as part orthi, rehum**l.<:dlT\"lLl~** will furlhcrnsk sl"g; ·'frc"{·zmg" in Ihe barrels and lower lu",ace. Redtlcll1g lhe number or-aelivc cydones whIch are air- and fuel-slaged to accommodale**redu~ed** firing rare, while opcrdling a co"I-Jired boiler Wilh rebum and ,eparaled ove, IJre air is**lh~ Iyp;~al** **"ppro"~h** to avoa] sbg I"pping problems.
]'olenlwl NO" cmi",wm rcducllOn performance lS expecled 10 be limiled 011 lignilc-fired cyclone boilers with a basic fonn ofsepamled overlire air**sys(~m, <in~e**  lhe rehum fuel mjeclion localion is expected lo coincJde with the eXlS(ing liguile pre-dryin;: "y'lcm venl purlS. The arno,mt ofoxygen introduced bytl'e ,'enl perl\ will be rlioruplivc 10 'my convenlional rebum process ill Ihal it would require mueh highc"]" rcburn rucl**inje~lion r"t~s**  lO "n:ate a subsloichlOmetric atmosphere in Ihe lower**sc~ofi,bry** furnace that is conJueivc to promoling in-furnace NO" reduclion_
SigniIiCOfil addilions lO the fuel prt:p"nrlion equipment ill the cxisling plam faeililies will he rcquired. The cool rt:bum sySlem expc'CI"dlo bc "pplied to MRY Sialion boilers may use Iwo new finc-b'lind pulverize" and dynamic cla"-" lier< 10 aehi"vc**Ih~** level ofCo"Iparticle size dish-ibulion required.
11igherunb"mc"{l**~,,,bon** levels in the ilyash exhamled Irom Ihe boiler may occur, espeoiallywhen Ihe rdmrrt fuel i, coal, and Ihe regular burners art: fired with Jess Ih,rn Iheort:lieal amouIlL, or comb"Slion air comrrtonly pmcliced with the u,e ofoverflrc alL Lowering, Ihe reburn fuel injeolion clevalion, JC'Cfeasing

Burn> & McDonnoII AI-IO Murnkela**Puw~r** Conpo""i,'", Tne,APPENDlXAI Technioal Fea,ibility Asses,ment Dolail, for NOx CcOlrol Technologic.,; NOx BACfAoolysis Study

!he amount ofreburn fuel, and grinding: lhe rebum coal 10 a greater degree offineness can hclp 10 offset
sume ofthe increase in Ilyash unburned carbon conlc'TI!. Rue gas opacily from the slack may inorease if the panieu]ale removal equipmcnl is an elcclro,llIlie precipitalor, due primarily to reduced resislivity and ,mailer partiele sizes ofthe Ilyash.

An issue that ulTeclS the**fea"bi~ly** oflignite reburning is 1he uplime required fur the lignile rdum fuel pulverizing systcm, and impaci oflhe rebllnl sySlem on effccliveness in reducing 

### NOx emissions during: load changes and lowerloads. Typicully, one new pulverizer is dediculcd 10 prqmrcrebllffi fuel in exi"ling pulvcri7,.ed fuel-fired boiler upplicalions. Cyelones may 

### be fired with less fuel ordeactivated during boiler o""ralion in order to accommodale ohanges In fuel combustion characteristics, boiler load, and for schcduled or unsoheduled individnal crushermuintcnance. Milton R. Young Station Umt l ha.,

scvcn crushers for cyelonc coul grinding, cach dedicaled to one oflhc seven cyclone furnaces. Diverting
as much as 30% ofthe total heal input as reburn fuel could require lwo oflhe exisling cyclones 10 be deactivated, and two new MI'S-89 pulverizera to bc dcdicated to rebum fuel preparation. As each of

. Ihesemills requires periodic·maintcnance"boiler emissions and/or.load cnuld 

### be negatively.impaoled during'individual rebum mill outage periods while the boilerremained in sCTviec. 

### A high level of fineness ofcoal p.rtieles from (he rebum mills is important (0 achieve and maintain in ordcT to limit incn::ase, in flyash combustibles. A minimum of60 percenl passing through 200 mesh fineness is**recommcnd~..:l** by One ofthe reburn technalogyvendors (B&W) for pulverized lignite rebum. Mieroni7.ed coal reburn requires even greater finene.,,: 70"80 percentpassing Ihrough a 

### 325 mesh screen.

Pulverized or micronized coal reburn with Ihe advanccu form ofseparaled overllre air (ASOFA) oan be applied and inslalled on 

### MRY Silliion Unit I's boiler. These combined lechniques arcexpeoled 

### (0 reduce 

### NO, emissions npproximalcly**5~%** from currentpre--conlrol buscline levels (down 10 0.385Ib/mmBtu) for Ihc 

### MRY Sialion Unil I boiler. These levels of

### NOx reduction depend on the advanocd form of separ.lcd overfire air lechnique 10 achieve the expected 

### NOx reduclion percenlages when applied 10 lignile-fired eyclonc boilers, which may nol he successful given the conCernS expressed aboullhe 

### • pOlcnlial impacts ofIhis lechnique. Uaing finely pulverized lignile forreburn fuel is considered lechnioally fcasible for 

### NOx emissions control under ev.lu"lion for applicalion 10 

### MRY Stalion Unill 's hoiIeL

MCnnkol' PowerCcopornli"". Inc. AI_11 

### Bums & MoDonnellNOx BACT Anoly,is Sn1dy Al'PENDIXAI Technical FcosibiJily A>se»m<I11 Dtlall, r<lT NOx Control Tcdmologie3


### A.1.2.7.2 Conventional Gas Reburn Nal"ral**g~s** hn, been prcfCITC,1 as the rehurn fuel (Ifch(lice. Naruml ga, h•., bec-n <Jlilizcd forrcbum fuel In [I\'O**ha.,i~** apl',ooche" o(l"wnlion"l rebllln and fuel-lean gas relmm. In lhe conwnlium,l "pproach, up lu 30% oflhc bollcr'" lolal fuel heat inpul '"**"upplic~** 10 lhr rch"m zone,**followc~** by a ,ignificant 'muunl ofoverlire air for complelion orcomhllSlion plior 10 flue gases exitmg lhe hOlier.

Conventional gas reburning in a cyel(lnc-fired boiler has been available al Tenne'5ee Vnlky A" Ihurily's Aile" Sialion llnileL' #1 (JOO MW)**~inc.** 1998. The reburn lechnology provider**(ven~or)** claims NOx emissions WeT" ITduccd 67% from" full-Ioa,1 b;"eline of 1.29 (down 1(> 0.42) Ib/mmlltu when tiring;! blend ofweslern biluminous and PRB eu"I,", Conve"Dlional g"' rebum fuel input rales were rlOI availablejrom lhe ledmology vendor's lilc,"lure. Anolherreference source ofinformolion sliLled NOx em;f;.,ion' 

### were reduced 65% Ii-om a f"U-lo"d baseline of0.86 (down to O.JO) Ill/mmBlu wilh 7 percenl of d,e 101,,1 fuel henl**inpUI.'[jppli~<1;,"** rcbum fuel'.

A schemalicgmphicofconvenlionalgasrebllmon;lp

..**lv~riz("(1** coal-fire,1 boiler;" "hoWTl in fiRIlre A.I- 

# , Figure A.I-2**N~tnr~1 G~s**  

### Rebllrll**Applic~tion** nn 

### Wnll-Fired Pulveri7,cd Coallloilcr willi 

### Onrlire**Air~**

Bc>LER 

# <.

ECoNOMJZER OVERFlREAIR**NAlUR~L** GAS RECIRClJlATfD

HUE GAS WNOIl°>:**c~,** 

# "" LOW-NO, BURNERS 

### • • -**R~RURN**
,**ZON~**



### • • 

# . '"'}**"""T'T';;;~**

### ~I.LL~ "**W""":'-~""'''''.'**

TO OISf'OSA,

BIIm., &**~cDuItndl** Minnko," Po,",,,, CoopeT.Jlivc, Inc.APPENDIX AI Tcchnioal Fcasibilil}'Assessment Detail., for NOx ControlToehnologies NOxBACT Analysis Smdy

Similar 10 !he applicalion ofseparaled ovcrfire air, there are polemial impacts and limilations unique 10 Ihe firing ofNorlh D",kola lignile in cyclone-fired boiler>; Ihal should be rectJgniZ<...:J as part ofIhis emission reducllon technology applicalion_ l'or Ihe moSl cJTeclive NO" Teduction by npplying Ihe various available fonns offuel rebum, lhe injeclion offuel is usually pLTformed using recirculaled flue gas as a**,hlu~"t** al\d carrier media lo "id dispm;ion and avoid completely oxidizing Ihe oarbon nnd nilrogcn componenls in lhe**fu~** 

### 1and furnace gases from "taged burnersfcyclones_ Illl'roved gas reburn**d~signs** have**r~duced** or elimillilled FGR wilh higher gus injection pressures. For lignile-fired cyclone boilers, rebum fuel firing with a basic form ofseparaled OVLTfirc air is exreolod 10 be much less cffcclive in reducing NO

### x emission:; than previously demon:;lraled**ds~whcrc.** This is related to the likelihood Ihal !he injection of reburn foci will he near Ihe elevation oflhe existing lignile drying sy&lem vent ports, and !hal lhe oxygen inlroduced w;lh Ihe lignite drying &ystem's venled moisture win disrupl the**d~.,ir~d** infurnuce nitrogen oxides reduolion process.

11 should bc recognized Ihat application ofair-staged cyclones wilh hasic oradvanced forms ofSOFA '<c.,. with rebllrn leehniques will require**th~** overfire air injection ports to bc.Joca1ed at a somewhat lower clcvalion of!he furnaoe compuTcd wilh uir-slageu**cyolon~s** wilhoul reburning. TIus mCanS Ihat 

### less airslaging ofthe cyclones may be**pmc~oed.** or thai less**resjd~nce** lime will be**~vailahle** for Ihe in-furnace

..NOx reuuetion process 10 OCCUL

Similar 10 coal rcburning, lhere are COneernS !hal wilhholdlOg a significanl amount ofhcal inplll from the eycl"ne barrels to Use nuturnl gas a, a source ofreburn fuel may reduce cyclono ll'Illpernlurcs enough to inhibil slag formation and Ilow, especially as boiler load is reduec-d. Air-staging Ihe cyclones for use of separaled ovcrfirc air 10**funh~r compl~menl**  combu'lion NOx reduction as part oflhis reburn leclmique wi]] further risk slug: "frcC',,;ng" in Ihe barrels nnd**low~r** firrnace_ Reuucing thenumbcr ofactivc cyclones which "TC air· and fuel-staged 10 accommodale reduoeu firing rale.1 while op=ling a coal-fired boiler wilh conventional relmrn and separated overfire air syslems is !he typical approach 10 avoid slag lapping problems. Natural ga,rebum wjlh Ihe ndvanccd form of&eparaled ovcrfire air (ASOFA) Can be applied and inslallcd on Millon 

### R. Young Sialion's Unit 

### 1 boiler.
Although the unit opcmting and c"pilul cools 1<> supply large qnantilies ofgaseous fuel not currenlly available allhis**sil~** are economic di."dvantages, using high-pressuTC natural gas for rebom fuel i, considered rechnioally feasible for

### NOx emissions control under evalualion for application 10 MRY SLaI;on Unil l's boiler.

Minnkola Power COOr."liive. lno. At_13 Bu",s & McDonnellNUx BACT**A~"lysis** Srudy APPENDIX AI Teohnic"l F"",ihiliry A

...,""mcnl Dcl"l, for NUx C'.ontml Technologic.,



### A.1.2.7.J Fuel Lean Gas Reburn ALlolher approach 10 Pi'S "ebur"iog is "flld-IcHn gas rebum" (FLGR"") lechnology, which injcclslimllc<l amounls ofnalural gas (opproximalely J-I0 perce", ofIhe tolal fuel he"l mpul) "hove lhe humer., (or cyclone.,) wilh 01' without .,ignincant**oir-sl~eing** ofIhc**b"m~n;** (cyclones) or lhe addilion ofovcrfire air**up~lream** of**lh~** fuelmj"clion dcvalion. FLGR'R Ijest neld-leRI on 0 cyc!om'-fired boiler

## wa" at ComillonwealLh Edl,on'" Joliet Unit (, (J27 MW), "**9_cy~IOl"".furnace** bOiler"

_ NO

### xemi",;ion, reduclion with I'I.GR (wilhoul SOl'A) was believed 10 he approxim;llc1y 35.-10% wllh 7% ofIhe boiler',**10~"l1** fuel hcat inpul**suppli~cl** in Ihe rcbum zone. This test yielded**O_5~** Ib/mmBlu 

### NO

### x emission, jj-om a ha,eline of**O_~810** _ One othercyclonc hoiler has been modeled using computational fluid dynamic> (CFD) '" p"rl ofa sludy looking at applying FLGR at Owensboro Municipal !JrililieR' Elmer Smilh Slalion Uml 1 (150 MW .,illgle-wan, ea,tern bituminous coal_lired bOller). Thi,; morlel predicled tharNOx emissIOns coulcl be reducedby 25·30% Olver thai aohiev.ble from ove-rfirc "ir and SNCR "_

More commonly. FLGR'" h"s bce." applied 011 medium lo large pulvcrizccl 

### co"1 wall-fired hoilero hurning ea.,rern hltuminous orwe,lem suhbiluminous eo"]<;_ On Wioconsin Electrjo PoweTCompany', (WEPCO',) PJcn,'ml Prairie Unil I, a 620 MWg 

### Riley lurho-r,,,,cl wOl·bollom (slagging) boiler, FLGRTM alonc was prcclictcdlo r",luce 

### NOx ,missious by J5-]9 rercenl at a !l'LS rcbLlmlale of7-8 I,e,cent hul only achieved 20% tl-om a baselinc of0.45 Ib/mmElu"-"_ Tllis lS pre,umably wllhou[ burne" "ir-sl:lgm£ or SOFA. II has also boen applied in combimllion ",ilh SNCR allh" WEPCO silO.

A poll'llli"1 adv,mlago of!'l.GRTM over convenlional gaR rehum is th"1 the furme, is generally comralLble wllh, lml does notrequire, lhc instalblion and opemlio" of.sOFA_ The slaged reburn 

## r uol**i~** inlmducorl inlo an oxygen-rich almo,pherc dO'Vllsh-eam 0 f Ihe humers and any OFA injeclion**poinl~.** Thc "mmllli of "olmm ruel jnJecled is typically limiled hy acccpl"hJc carbon monoxide levels in lhe boiler exil nIle gas.

There are**poten~al** impacls and limilaliom unique lOlhe firing orNorth Dakota lignM in cyclone-fired hoilm lilal should he recognized as part oflhi:; emissiun reduolion technology applie<'lion. This is .<ignificanl, c'"pccially for**aliem~li** ve, wilh FLGRT

.. technology when cumbined wilh hasie Or Hd\'HnOccl .sOFA 10 aHow lhe nalural g"s introcluced ahove Ihe SOFA port" In bum completely prior 10 Ihe furnace**c~il** plone_ In eilhercase, lhe amounl ofaddilional pOlenlial NOx reduclJOn I'",sible with FLUR I>t is limilcd_ sincc the rehum lilel injeclion lo,alion is expected 10 coincide wilh Ihc exisling lignile prc.,lrying "yslem vcnl porto. The arnounl ofoxygcn introduced by the venl port, will be di=pllVC 10 Ihc fud-lean

Ilum, & McDon"ell AJ_l4 Minnko," Power**COop~,"live,** lnc_APPENDIX AI Teelmi"al F,.,ihilityAssessmeJlt notail' forNOx Conlrol Technologios NO>< BACT Anal"..;, Study

reburn proeess in that it would require much higher relurn fuel inJeolion rates in 

### Lhe lower secondary furnace to promote in-furnace NOx reduction. There are reduced concerns thatth. wilhholding**of~** modest amount ofheal input from the cyclone barrels to usc natural gas"s" source 

### ofreburn fuel may reduce cyclooe lemper"lurcs enough 10 inhibil slog formation and flow, especially as boiler load is reduced. Air-staging the cycloncs with the nse ofsep"raled overfire air 10 further complement combustion 

### NOx reduclion is an oplional part oflhi, reburn technique which will f"rthcr

### ri,k slag ·'freczing" in lhe harrel, and lower furnace.

Fuel lean g"S reburn can be applied and installed On MRY Slalion Unil I·s boilcrwilh or without SOFNASOFA. This lechnique is considered lcclmica.lly feasible for appllcalion 10 MRY Slalion Unil I's boilcr_ Expected 

### No", reduction will be modesl forFLGRTM without SOFA and FLGll"" with" basic form ofSOFA. Unil opemting and capilal cosl, to supply large quantitie, ofllaseons fuel**~ot** currently available .1 lhis site are economic disudvanLageo. "Because ofthe,e fscton;. lhesc varistions ofthis technology will nOt be cost-effective compared lO olher allern.lives wilh simibr OOntrol effeclivcne's. ".-**-FLGR~"** witho-ul SOFA and-FLGR"" with a basic form ofSOFA wcn:'not'included-in-lhe-conlrol ',...**effectiv~"ilcss** and cosl-effecliveness seclions oflhe main fl.."porL

.Olhcr demonstr"lcd forms offuelle"n gas rcburning in comhination wilh po>t-combuslion lec1mologies,

.such a, amine-enhanced fuellc"n ga' 'eburn (FLORI>< wilh SNCR). are di,cusse<! under lhe layered lechnologics seclion_


### A.1.2.7.4 Fuel Oil Reburn Fuel oil h"s ken SUbsliluled fornaruml gas in a convenlional reburn applicalion. This is much 

### 1c" cOmmon in the UniK-d Stale, lhan u,ingnalural gas as a reburn fuel, due to lhe genemllack ofdem"nd "nd difficulLie' in supplying lhe volume offuel oil which would be required. II ha' been insLalled commereially on three 350 MW oil-lired boilers in New Brunswick (Canada) allhe Colcwn Covc plant NOx emission' reduclion with reburn and SOFA was**7~%** with 25% ofthe boiler's lotal fuel heal inpul supplied in the reburn zone. This yielded [}_22 n;/rnmBlu NO

### x emis-,ion' from baselinc of1.0 Ib/mmBru'. No cxamples of**conv~"illional** fuel oil reburn applied 10 

### acoal_lired cyclone boiler were found in av"ilable likralure.

Fuel oil reburn could pOlcnlially bc**consid~'rCd** for application to MRY**S~lion** Unit I and Unil2 boilers_ Invesligalion ofthe specific source, dislancc, and 

### costs for ,upplying si6'11ificnnlly increased quanlities of fuel oil vin lransport trucks hauling lanker trailers orunderground pipeline 10 M.R_ Young slnlion has nOl
Minnkola POw<'1" Cooperative, lno_ AI-15 Doms & McDonnellNOx BACT Analy,is Study APPENDIX A] TechnioalFeasibilily**A""ssm~nt** Del"il, forNUx ConTrol Technologies

been p<-Tfomled. The umt operaliLlg oml capital co,ts lo sllpply large quanliIies ot"high-volume liquid ro"il fuel al tl", silc me economic disadvanlage,. The concern,;**r~ganling** polenli"l imracls ;md hmilatlon, uniqlJe 10 the firing ofNorth Dakola lignile in cydo,",,-lircd boiler>; lhal "hould be nxogni'"d a, pan oflhis emission**rL~lue(jon** lechnology "pplicolion UTe Slmilor lo lllo,e expre"eu for**conv~nlional** I:ns reburn_ H i,**hch~ved** lhal**1'01~llliul** NOxconlrol wilh oil**t~bum** would hc slighlly less Ihan comparable convemional AUs [{·bum 'y,I'--n18.
Although fuel OJI rebllm could pOlentially be coosi,bed for apillioalion to MRY Sialion Unit 1's boiler, lhe lack orany di"linct pOleul;.1 NOx redUCli\m .dvantages "n,l demonslral,on on cyclone-frred llOilers doe., 1101**"pp~ar** 10 sUIlPOrl ii, eonsideralion, 1'h1, aJlemnlive w"s nol included io lhc NOx conlrol and cosl-effccliveness analysis.



### A.1.3 Posl-Combustion Controls Post-combuslion cOlllrols dcal wilh Iechlllqlles lhatlhcmmlly or chem;c"Jly_lrenI Ihe Due ga.,es 10 reduce NOxemissions .ner lhey have exited Ihe boile,'s lower fUnlace_ III Ihe**C",~** ofMIllon R.**Yo"n~** Station Unil I, lhi, t'nmurily involve.' forms of""leclJ"" calal}1JC r"lhJclion (SCR) anu ,eleCI;Wnon--caUilYlic teducliQn (SCR) lechnologics. Another emergmg lechnolol,'Y that has recenlly eLllored Ihe comm"rcia] markcl is Powe"'l'ao's Eleclro CailllytlC OxidaIJort', WhlCh treal' nlilityll(11!cr 

## nIl" gas fo,· removal 01' nilrogen oxide.', ",lfll[ oxide" and mercury. Another emerg;TIR lCchnolo;,')' Ihal has recen(]y enler"ll Ihe**com",~rei~1** ulillly air pfJJlution contrQI morkd is Powerop"n'" JOleetro Calalytic lliJdation"'. which lreals holler nllc 

## ),'<," for removal ornitrogen**oxirl~"** sulfur oxides, anu mercury.


### A.1.3.1 Selective Non-Catalytic Reduction (SNCR)**Sel~Cliv~** Non-Catalylic Rnl)lclion (SNCRj, and val'lalions such as hydrocarhorHnh,mccd SNCR (sold under Ihe Irade name ofNOxSlar'fM), nnd Rieh Reagenl Injeclion (RRl), aIT 

### "II posl-comhnstion lype., o[ bfJiler NOx**~mi"ion** commk Whde lhe,e tcchnologies**ar~** in,cn"live 10 the specific flld type, whose COmbUSlion proullcl' are being lrealed. lile largo l)lajority ofboil

### er"pplicaliom 10 dalC have been On pulverized coal-fired unilS burning eamen' hituminous ["ds. SNCIl has httn tlS",llo reduce NOx el11;."ioll.' 011 numerous**u~llty** hoilers burning ea,lern bituminous coal, midweslern biruminous cool, "nd. to a lesser exlenl, westem suhhirum;nolls ooaL SNCIl hos also been used wilh fuel oil and natural g"'- r",,-d llnil,. SNell (and hydroe.rbon--enhaoe",l :'>NCR) l"Chnologies can e.ch he applied [0 cyc!<lne boile" Wilh or wi'holll lhe u,e ofa SOFA 'ystem, SNCR docs nol "ppcarto be del'''wknl directly on the 'Yl'e ofburners (wall-fired, langenlinlly-fired, and cyclol\e_r,rcd) employed in the !mllers whe", il has

Bum, & Md)unndl A 1-16 Minnkulo Power Cuopcrotive, Ino.APl'ENDIX Al Toehnieall'easihililyAsses,mOI" Detail, 

## roc NOx Control T<ehnolog,", NOx BACfAnalysis Sludy



# , ' heen installed, with orwithout overfire air in full opcnttion. Opcrallon Ul th"", plants has demonstrated thal SNCR can decrense NOx emissions as much as 15-40% at full load, mo,l typicallybctween 25_35 percent".

In the conventional SNCRprocess, urea or ammonia**i~** injected into lb.e boiler in a rcgion where the combustion ga' tempe",ture is in the 1700 to 2100 degrees F range. Underthese lemperature condilion" the urea reagent lCO{NH,), 

### Jor ummonia LNH,] reae!$ wilh Iho NOx, forming N, and water, reducing NOx emissions.
Long·tctm examples where SNCR has been 'Ised to reduce NOx**emis~ion,** on two oyclone-fired boilcrs
are on a 

### 13& MW uni' 

### and 160 MW unit burning ea,tern bituminous coal al Cone'Ctiv's B.L Englaml Slalion (Units 1 and 2) ,inee 1995 and 19%, respectively. Tests u( these planls demonstrated that SNCR
can decrease NOx**emission~** as mueh**a~** 30-36% at full load, rrom uround 1.3-L4 IbfmmBlu respectively to uS low as 

### O.gS IbfmmBtu (without ove-rfire air)"'''''". ThesehoHen, located nea, AtlantiC CiIy, New

.Jersey, con-l,i,u'eLoopei':iteSNCK(with-Of"A) roi""Jlili,ual'NOx'CmLs,ions- around 0.55 and OA5'lb/rnmBlu,

. '. 'respeotively.

SNCR oan be 3pplied and inslalled on MRY Station boilers. EslirnulCd NO

### xemis.'ionrnlCS for osirt&

. SNCR wilh North Dakola lignite considered published levels achieved by cyclone-fired units firiTIg

weslem suhbilnminOll' coal, and vendor prediclions. SNCR alone is expoeted to reduce NOx**emission~** "pproximJlcly 37% from MCR bJseline levels (downlo around 0.5lh/mmBlll) for lhe MRY Slalion Unil I boikr wilh ammonia slip limi[Cd 10**appro~irnately** 5 ppmvd. Becall,e orlhe opc,-ating costs oflhe consumed reagenl, lhis lechnology w,ll not be LOsl--effeclive cOTnllaroo \0 Olher allcmalives with similar control**elTcclivene~g** (i.e. SOFA), SNCR alone wus not included in the control elTecliveness and costelTccliveness sections ofthe main repon.

Other dcrnon.'lntc<! form' ofSNCR-reIJled lcelmologies, such as Rich R""genl Injection wilh SNCR, and "mine--enhJnced fuellcan 

### gas reburn (FLGRTM with SNCR), are discussed under Ihe layered technologies seclion.


### A.1.3.2 Hydrocarbon-enharu:;ed SNCR (NOxStarTII ) HydmcJrbon--enhanced SNCR lechnology, commercially markeled as NOxSlurTM, is offered by a single vmdor (Mil,ui Baboock) as a poSH:ombuSlion type ofenhunred SNCR lechnology, whereby an

Minnkol' Pow.:rCoop<ralivo, Inc. At ·17 Dums & MoD<JnnellNOx B/ICT AlInly,i

.. StlIdy /lPPENDIX/l1 Tednieal Feasibilily**/I"e.~,men'** De,"ils for NOx CUlIlml Tecllllulogie'**~mmunia-based** re"g:cnl 

### is conlinuou,ly injecled inlo lb<: "upc'Th""ler/rehealer pass of an opc'TIIting boiler wilh small "muunls ofga.,eous hydrocarbon (typienlly either namrnl 

### gos or propane) and air or ,tC<lm 10 provIde**Jnn~,-** cuuling and aid reagenl di,pel ,ion. The targeled COmhUf;llOrl r.ns ImlplTulure rang" is hel we<." 

### 1500"r: nnd 

### 2000"1'. The allluuni ufg",COU' hy,Jrocarbon inlrooucnl " 'mall erou(lgh 

### (0. I I" 

### 0.2% OflOLOI f(ld heal input) lhallh" is nol intende<110 "01 as a form 

### ot·rehum Or "Iuged fllel combuslion. All "'THy of**l'ermnTl~nlly-illslalled ijJie~lion**  hmces aI e**10tal~d** wllhin Ihe boiler conveclioTl pilS" divided inlo numer1)", <hserele zone" across Ihe full widlh nn<1 hcighl orIhe dUCL**Th~** hy<lru<:arbon aUlo-igmtes. forming hy<lroxyl (011) rad,cals which reaCI Wilh the NO, and ammonia 10 produce elemenlal nilrogen (N,) und waler vapor (A,O).

NOxSlarTM was demon,lmled alTennessee Valley Authority's Kingston Power Slnlion Unil 9 (taLlgenlially_fired 200 MW lwin-furnace hoiler firing ",,"Iern biluminou, coal) 

### in 2002". Tllis technology was "uh.,equCT1tly pcrmanen1Jy-inst"lled"1 TVA's Colberl SI"llOn Um14 in late 2003 on a 192 

### MW wall-fired hoilcrburning easlern billlminous coal". NO" rcdu<:lion wa, ,taled as 

### 68-80% 

### fOl' Ihcsc "pplicat,oLlS, which included the imp<1el ofoverJire air and <lir_slaged comhustmn "pstre<lm oflhe ammonia**~nd** propane iLljeclion loealions_

An example ofa hydroearbon-enhanct:o<:l SNClt insLallaliOll On" wall-IlTcd pulverized fud boiler is ,huwn as" secliorlal**sid~** c1ev<llion view oflhe (lpper Jumacc in Figure A_I-J.

flm,,, & McDon"dl AI·IS Mi"nkoLa Power Coupera""", Ino.c - APPENDIXAJ Technical FeoslbilityA'<essmeJll Delails for NOx Control Technologies



### .",...-,--- 

# ---- NOx BACT Analysis Study

NOKSIOTTIt ammon;alhydrocarbonJ,loam injeclion lanoe, {venical lanto, bohiod secondary superhealerinlel rubes



### Figure A.1-3 Hydrocarbon-enhanced SNCR Application on PC-fired Boile,-22

The supplier (Mitsui Babcock) ofhydro=bon-enhanced SNCRtechnology claims there is liltle sensitivity lo the type fuel (coal) or burncrs this lechnique can be polentially applJed to in order to reduce NOx emissions_ The chemical reagent injection forhydroearbon--enhance<l SNCR (NOxSlarTIt) NOx control technology must be precisely locaLed 8Ild carefully controlled 10 be effective. Operation outside ofthc required operaling muges can even resulL in increased No" emissions. EXlenslvccompUlalional fluid dynamic (CFD) model simuJlllions are needed to delcrmlne lbe optimum injectionpoinls and spray patterns_ Boiler operaling conditions change wilb unilload and varying fuel characteristics. The NOxSlarTM process con

### 001 system musl be able to a<!jusl for lbcse changing conditions in order to be eJTeclive lhroughoulthe inlended load range and firing C<lndilions encountered. Non_relractable ammonia injcction lances arranged in a parallel-series m\inner 

### are pcimanenlly mounted inside lbe upper furnace zone, attached 10 conveclive lube elemenls. DiITcrent sections oflhe injcclion "grid" can he turned offor on, depending on load and firing condilions and amounl ofNOx reduction required. Injection nozzles are continuously purged and cooled by exlmcted superheated steam from the boiler's main steam outlet, whelher ammonia reagentis being inlroduced into the flue 

### gas stream or 

### not. Ammonia slip 

### can be minimized by Injceling less reagent, allbough 

### NO x conlrol performance will be reduced_

Miankola Power Co",ernl;ve, Inc_ AI 19 Bums & McDonnellNO>: RAC1 Aual,.,i, Srudy APPENDIX AI Ttthnical FeaslbJlly A,,<ssmenl Detllil< lin NO;< Comrol TeeJmologies

.._-- There are a number ofissue, wiih tiriug Norrh Dakola hgniteIhat make !he applicability ofhydrooarbonenhanced SNCR iufeasible compared to previous expericnce m olher ooal-fired**p"wel'Pl~nls.** These issue" iuclude:

• Hydrocarbon-enhaneed SNCR (NOxS tar''') lcchnology has nol beGu applied to cyolontboikr,; (wJIh or wilhoullhc uoe ufa SOFA**sy~lem).** II ha, b""n only '1'1,licd lo dale On pulvenzed coal. firetl bOlkrn burning ea31em 

### III tumino,," fuds.

• There i, no sucoessful u<-1llomlr"le,1 full-scale cxperiencc In 00111 inuous SOn'lCG ofhydrocarbon" l"1lhuuee,1 SNCR (NOxSlarTM) leclmology on lllll1s finng high-slagging coals such as we.slem subbilllmiuous (PIlB) and ligni,e. The heat transfersurfaces in lhe conveclive heal tTnu,fer zone where the rea.gem mixture lS mjcclcd**~re** prone 10 severe fouling fl'Om Hyash con,liluenls**~ummOu** in North Dakoia lignite coals. Fly"sh deposit**"c~umulalion** on lhe oulside oflhe NOxSlarTM Junees in Milton R. Young Sla1ion Unit 1 boiler'snpper furnace is expected 10 be significant, potentially occurring within a matler ofa few weeks from slartur and nearly imrO",hle to prevent or remove efJecllvdy dunnghoiler operation_ Sueh bUildup is expected 10
eanse rnaldislribnlJon oflh. 

### NO

### x reduction chemical reagenT from ihc mjeelion nozzles.**EITe~ll V~**  ou-hnc removal oflhese deposits from lhe injectiou**nozzl~s** is anlicipaled to 1>e insufficient to maintllin**effec~ve** injection di<iribntion and volume COnTroL his anlieipaled thar 1hJ$ would significantly reuuce Ihe NOx emissIOn reJuclion**perfonn~noe** eonsi;tcnlly "ChleVed On
a SUSLainabJe basis.

The lack ofexperience wilh oyolone boilero,**~specialJy** lhose Gring coo.l wilh**SO~Cre** deposilion oharaolel"istio, such as NQ"h Dukola ligmie, makcs thi, leehnolugy leclmiOillly**infeabibJ~** 

### for application

on**Lh~** MiHan 

### R. Yuung Slalion Unit I boiler.



### A.1.3.3 Rich Reagent Injection (RRI) Rieh Reagent Injection (RRI) is 

### a

### NO

### x control process thal**h~s** been developed and demonslraled specifically for use on cyclone boiler,. Rich Reagent Injection IS an SNC'llprocess thaI iovolves lhe injeclion ofaqueons urea into lhe lower furnace belween Ihe oyclones andthe SOFA pOri(;. RRllmgels a high**1~1llperntllre,** fuel·rich ZOne wilhin lhe boiler-fumace enviromnml imrrn:<lialely adjacenl to**lll~** oyclone hurners, and requires tempernmrcs in the**rang~** of

### 2400 (0 3I00 degree, 

### F.

The three zones ofa Rich Reagent Injeclion SNCR applieauon on a hoiler wilh sep"-rnled overfire air are shown as a ,ectioaal side e1evalion vi",,' of!he n.lmace in Figure 

### A_l-4.

Dum, & McDunndl AI·2U Mllwkola Power Cuuperative, loc.APPENDIXAl Technical Feasibility Asse_"mentDetails forNOx ('.ontrol Technologies NOx HACTAnalysis Study



# OFA BumoufZone 

# N
Chemical Injection Fuel Rich Zone



# Fuel Staged Combustion Zone

Figure A.1-4 Rich Reagent Injection Application on Boiler With Overfire**Ai~**
The Rich Reagenl Injeclion 

### (RRI) process has been successfully demonslrnled On al 

### least two eyclonefired hailers, wilh Ihe mosl recent installalion at Amercn's Sionx Unill, a 500 MW hoJlerfiring a hlend o[PRB and mIdwestern bituminous coals, Generally, the heal content oflhese coals typically varies very lillie- ShOrl-lerm lesting ofthe RRI process has been performed alone and in comhination with SNCR on 

### B.L England Unit 

### 1 in 

### 1999"''', and more rcqmtly alAmeren's Sioux Unit 

### 1 in 20022l.l', 

### in 2004" (alone), and in lhe flfslhalfof200S" (alone, and with SNCR).

The 

### RRI process is intended to be used only with air-starved (suhstoiehiometric siaged-air) cyclone combustion, in conjunction with the installation und operation ofan 

### OFA syslem. 

### The RRI process ha. nol been demonstraled On any nnilthat fires North Dakoll1-lignire. As ofMay 2006, no commercial installalion ofa permunent Rich Reagent Injeclion system has been made al any cyclone-fired boiler_

MiImkola Pownr Coope,rnive, lnc_ Ai-21 

### Bum. & McDonnell**NO~** BACT AnalySIS Sludy APPEi\'DIXAI Tedmic,j FeasibIlity Asse"mcnl DetaIl., for NOx Control Technologic, 

# -._-- TlKTe" only OIle holder o[a comrnenaal license fOl modeling and cOIlcepluaily designing: RRI (Reac1ion Engineering- InlernUlion,i), wllh lWO vendors sUh-lieensed to design and sell RRI cquiprnelll (Fuel Tech and CombnSlion COlnpom;nl' Assoeialcs). Since these heense agreemcnl' me in place, and considering lhal**:;lIc~cssful** dcmonsh'alion IcsImg ha:; bcm performed ullWO cycinne,lircu bOller powerplanls. lhi, technology i:; considered to be appheab!e and commcrclally av"l.blc for potenli.l applicallOn on cyelone boilers winch burn coals wllh hcal comcnls lh"l are relatively constant. Howcver, due lo lhe ,'"riahle hc,.l content or 

### Iignile coal, 

### RRI is conOldcred to he technically-infeasible for "ppl**ic~twn** on Norlh DakOl<! lig" ilC·fir"J boilers. Tcchmcal Lca,ibil, ty ami expecled NOx emissions from 

### RIU for appJicatlon On the Millon 

### It Young Slntioll Unil 

### I boiler are induded in lhc "Luyeroo NOx R"ducIIon Tcchno]ngid'
seclion.


### A.1.3.4 Selective Catalytic Reduction (SCR) The lowe..,t MOx emisRion levels from coal-fired utilily boilers are rypicaHy achievecl by in,lalling and operalmg ocI""live cal>llyli" reducrion (SCR) ledmology. In ll,e SCR proc,,"'s, Ihe gaR slream iR pa"ed thL'ough 

### u calaly,t bed 

### in U,. presence of**ammoni~** lo rednoc NOx 10 moleonlur nitrogen and w.It.--,-. The process is lennoo ">cl ective" lxx:anse the anunonia preJCl\:nlially reacl' M(h the No,., ralher thun with lhc oxygen in thc flne ga,. 

### Acutalyst is lIsed 10 enhancc NUx reduction ancl ammonia ulilization at aPPrOpriale fine gas lc'TI1peramres. SCR is u:;ually applied 10 Due gas in lhe 600°F to 750"F tempemtlue range. There are**vnria~onR** in Ihe SCR proccss for ooal·fired bOIler<; lhaI mostly Involve locations In lhc Jlu" gaB path wh"re the calalysl is plao"J in order 10 promote Ihe desirecl NO

### x emISsion I'educliou erfed. These are dcscTibed below.


### A.1.3.4.1 High-Dust Selective Catalytic Reduction (HD-5CRJ Forcoal"fired hoil"'s, • convenlion.l SCR reaclor nlilize:; readily-ava,lablc**c~l>lIYSl m~lerials**  and reagent In lhe form ofarnmonia_ 

### Aconventional SCll reaotor '" commonly ins",Hed in ahigh-dnst, hal-side**aIT~ngemenl.** located bClween the ecunomiZi'r ouJe[ and air healer inlel where lhe nne 

### gus lempenllure;s within the de."ed operallng 

### ranI,'" for lhe SCR catalyst The convenlionn! SCR reaClor arrangement is preferred 

### for mo,[ coal-fired applications in nlilily boilers hecan<e ilnvoids lhe aclJed expen:;e of rehea1ing Lbe nue**g~s** ifplacoo alIer the air heatel'S whi"h cool Lbe flue ga,. and down, [ream of.ny flue gas treatmenllO remove aCid gases_**Conven~onal** SCR technology uses an ammonia injeclion grid (AIG), which consist, ofmnltiplenozzles, [or dislnhuling lhc reagent inlo lhe flne gas al lhe boiler's economizer fine pis onllel.

Burns &0McDonlloll Al_n Minnkola PowerCoope",'ive, Inc.APPENDIXAI Technical Feasibility A"c<smenl Derails for NOx Control Teclmologies NOx BACTAnalysis Sludy

A schemnlic graphic diegrnm for a conventional high·dusl, hoi-side SCR system on a boiler with a flue gas dcsulfurizalion systcm and stack 

### gas reheat is provided in Vigure A.I-5. 

### Figure A.1-5 Convenlional 

### High-Dust SCRArrangemenl with FGD Scrubber OutJet Reheat 

# High DustArrangement 

# CD Steamgenerator 

# ® Regenerating heatexchanger 

# @AJr 

# o Electrostaticprecipitator 

# ® S02

-Scrubber



# ® SCR

-Reactor 

# ill Catalyst 

# ® Vaporizer 

# ® Ammonia 

# IAir

-Mixer 

# @ Ammonia storage Lank

(figure copied from vrheelahralorAirPollution Controlliternrure)

Conventional high-dust, hoi-side SCR technology has heen installed on severnl pulverized coal and cyclone boilc<ll firing bituminous and subbituminons coal in lhc Uniled Slales. There are ..Iso a limiled number ofEuropean SCR iu

.....lla!ions on sleam eleclric generaling units (SEGUs) firing lower grade (brown) coal. Thcre 

### are, however, no existing full-scale SCR installalions on units lhal fire North Dakota

Minnkot. Powe<Cooperative, Inc. AI-2l Bums & McDonnellNO, BACT "'nalysi' Shldy APPENDIXAl Tttl1J1icol Fe.sib,liIj' Asse"monl Dolail. JorNOx COlllrol Tcclmologio'
lignile. There are approximately 50 cyclone-fired uroit, 10Clltcu 

### in lhc SMe,;**~lTccleu** by EPA's NO, SIP calL Over halfofthe.,e units nre**pl~nning** to**insl~ll** convem,oLlal high-dust, hot-side 

### SCR systems in rc'l'0nse 10 lhe SIP call, The in,tallalion ofconventioml 

### hi gh-uusl, hul-SHk SCI< 'Y'lems has heen**cornplcl~d** on apprnximtllcly 

### 22 ofthe'e unit,. Appendix A2Ii'IS sew",l eonvenlional hIgh-Just**hot-sid~** IJ.S. SCR inSlOll"lions on pulvetiu:d coal anu**cyclon~-lircd** utility boilers, along with measured NOx cmi"ions. Inilial dala fmln Ihese unils indicate thm conVenIlOl\a] high"dusl, hoi-side SCR syslems operaled on .'Ullilhlc cyclone-fired**unil~** muy bc ublc 10 reduce NOx emi'''ons to as**low~,** 0.07 IbsfnlTnBlu, Several SCR iLlSLallnlions have been retrofit on eXLSling cyclone.fire,l boilers buming: we,lem subbituminou, coal (or 

### PRE blended wilh midweslem b,luminou:; coal). For cyclone coal-nred utility boilers rell'Ofitled wilh SCR technology, all wcre ong:inally dC3lgned 10 burn h' tummous coal.

Thc EPA NOx Sil' call only applies to units in lhe eastern Uniled Slalc.,. Th= are no facililies firing Norlh Dakola ligmte in Ihe EPANO

### x SIP can region. SCR sysLem operution is currently only needed during the ozone seaWn (June

_ Septemher) for units insl"lling: eonlrul equipment "olely to meel lhe EPA NO

### x SIP call requirements. Limiled annuuI op"'Iation is a ,ignificant factor WJth respCCI 1o SCR equipm:nl reliability, mamtenanee, op..,,;llonal cos'.s, and catalY't life. The**dem~n<l"** on !he SCR By,tem

are much**mor~** severe irlhc C<luipment is required 10 OpetOlC On a full-linm, annual basi,.

Two hyprnduc!:S fromlhe high-dusl, hOI-side SCRprocess are ammonia slip and SO,:

• Ammonia Slip, Slip is ammonia lhat is unreacted in Ihe NO, emission reduction proceQ;. Maximum ammonia slip for a gas !ired unil is "sually 

### 10 ppmvd whereas, on a coal fired ""il. ammonia slip below 5 ppm i.' desire,l Forcertain applications, this concentration Can be problemalic, therefole requinng more catalysl to reduce slip. MoO' new 

### SCR "pplications have ammonia slip**gu~run\ced** at a 2 ppmvd mnximum for an inili.l opemling period.

• SO,: Due to lhe compoSltion oftypieul SCR calalysls, a small percentage or**mh~TI:nl** 

## so, w,11 bc o,,,dizcu 10

# ,,0,. This oxidation can he controlled by carul)'s1 sekclion anu can he Ie,s thon one percenL SO, 1o SO, oxidation mUSI be carefully controlled to avoid crealing SO, levels suf1ioienll)' high to rai,e**th~** possihility ofaIrhealer fonling. A unil filing high_sulfur**~oaI** with SCR tedmology is cspcci'dlly vulnerahle [0 SO, oxid"llon and ammonia slip.related fouling problems. Tho deposition and fouling is dne to formation ofsolid ammonium s"lf.le «NlI,},SO,) and liqnid ammoninm bisulfalC (NH.HSO,). The most important de3ign variable is optimi2ing lhe oaralysl seleotion**~nd** amonnt ofoal:ily'llhat will reduee NOx emissions, conlroI "nllllonia slip, and minimize SO, oxidalion.

Burn< & McDonnell AI_24 Minnko"'- Power Cuope, a!lve, IncAl'PENDlX Al Technical FC"-,Ibility Assessm""t Dctail, for NOx Contrnl TcdmologioOS NOK BACT An.Jy,i, Study



# -----------
Recenllechnology has allowed cUlalysl suppliers 10 makc mOre rigorous amI lenglhy guarantees. A reasonable inilial operalingperiod lor convenlional cataly'ls in high-<lust rcacLor ammgemenls on boilers firing eastern ormidwcstem hiluminous coal is uround 24,000 activc opemting houn> (Le. when ammonia reagent is being injecled). F"cIOrS thai need lo be laken inlo aooouni in**dc~ib'll** ofa high-<lusl, hol-side SCR application lhal affcolthe neoo for cawlysl replaoement are:

• Pressure drop: The ,mount ofre.,lriction 10 flue gas flow through Iho SCR inlet, OlIJImonia injeclion grid, SCRr03Clnr, and**dOWT1slrc~m** ductwork directly incrcase.s induced dran ran horsepower required lo mainlnin adequale boiler clrnfl. This is an importamparameter to consider**~nd** minimize cluring the design stage. Pressure drop is a function ofthe avemge and maximum SCR reactorducl velocities, the amount ofrc.striction caused by flow distribution com:Clion deVices (bames or vmes), and Ihe number and gcomelrical aspects oflhe c"lalyst layers. Many retrofil SCR inslallalions Tl.XJuire a booster f"n or upgraded induced dmft fan 10 overcom" the added now resistance. This increases operating cost for the increase in auxiliary power consumption and loss ofsaleable electric J:'0wer

..TI,e type and pilch oftho catalyst arc factor< mosl influenlial in delermining lhe amounl ofpressurc**dMt~**



### :>- CalDly" tYPe: The mosl commOn lYpe, oc fonns ofca1.:l1yst material arc honeycomb or plate. The fonncr offer< more surface area pec volume, bul can be more restrictive and pron" 10 pluggage from ash deposits. TIle luller is usually les.s restriclivc but requires more catalyst per layer or more layen; to achieve Ihe active surface needed 10 "chiove the intended NO

### x cmission reduction.

"**Ca~-l1ysl** Pilch: The pilch oflh" cUlalysl, a tenn u..ed 10 ,Iesoribe Ihe size 

### oftho gas patb openings IhlOUgh lhe catalyst, varies**,Jcp~'Tlding** 

### on U,e manufacrurer and dc:sign duslloading. Pitch is generally On lhe order of5 10 7 millim"lers. POlenlial pluggage offlow channels wilhin me cataly,ts layers is thercfore an issue thai muSIbe dealt with during design.

• Calalvst performance' Tbc amounl of

### NOx cmission reduction e>:pccled is a funclion ofIhe specific activity level ofIhc calalysl rnalerial and the arnoum ofcalalyst installed, over a given period oftime. Calalyst (onnulalion selcclion and fealures ofconslruclion bavc a signifi"ant impact on long.lenn 

### NOx emission reduotion and**subsequ~'Tlt** cosls for**=g~"TIl** and cala]ysts replacement. 

### The frequency ofcatalysl replacemenl is influenccd slrongly by:

" Calah.;t ern.sjon: Erosion ofIhe calalyst mnlcrial in coal 

### fired units from entrained nyash or scotblowing action reduces thc amowli ofactive surfaoe available forrcacting with thc reagent amI flue gas, and can cause distonions in gas distribulion**(~challllcling'')** through Ih"

Minnkota PowerCooperative, 

### Inc. AI·2S Burn, & MeDonnell**NU~** BACT Analysis Srudy APPENDIX Al Technical Fca,ib,li'y Assessmenl Demils rOT NOx Conllol**Tco~nologies**


### SClt**r~""c(or.** Ca(aly.,t mnler",l is fwgilc and can 11e easily damaged. Some caLalys( is provJded with =ion-resislan( top edges 10 miligntc (his ("I\dc"cy. 

## :>- J'\:loistur_e nhsoQl(;oo: Many types ofcalalyst are**~nmnge~** hy ah,orrtioo ormui,lure. Tho reae(or mllsl 

### be kept above "",hien( dewpom( (emperalures orprotecled from Ii**ee~ing** during outages in Older 10 l'rollL"ellhe eata[y,( from moiSlore damage. Spore calalyst mllsl be carefully p"ckagcd lD keer il dry and mu,( bc handled deliealely to prevent**danmg~.** 

## :>- Thl"Trrml degradi'.IJl'ln: TI,e :;peeifie aelivc demenL' "I· the carnly.'l Hurlaec, o. lhe malrix struclure il,elfupon which the calalysl malenal is "pplied, ean dcgw,lc when exposed lO flue ga, lellLllemlllrcs grealer Ihan lhe IIlleLlded <IeSll;Il ofthc formulation. J-hgh flue gas lemperulures wilhm tile reaclor causes oinlering, leading to a permanent 10""' ofcntalyst "OllVily due 10 a change ltl the poro siruelure orlhe catalysL Proper ,eleclion und manufac(uriLlg eonl",1 ofthe cat"lysl slructure nn,1 formulalion can minimize Ihennal degradatiO<\. 

### ;» CaLalYSI poisoning: The los" ofperlonn"nce or acllvily ofIhe calalyst overtime C"n 

### be due 10 chemical damage or 1'0;""niTlg. Two clements e.,pecJally derrimenlal to Ihe life ofcommOn**ti~mium-surponed vana~ium**  pcnl()xi<!e seR oaLalystare arsenio ami zinc. Vanadiallunf:.\len_bascd calalysls are I'arlicul"rly**susc~"pllblc** 10 rapid deaclivJIioH duc 10 gaseous al1>Cnie poisoning. In some German sen. inslallalions, a 50% 10.'.' ofaOI;vity ha" betn reported wllh", 10,000-15,000 upcf"ling hour.<. Addilion ofmolyl"fenllm 10 a**vana~;n"** lil"nium SCR calaly.'l On Olmilar apphcaliom "hows relalivc oClivily TC"{llIchon" of20_25%. Progre"sive loss ofSeR NOx redUClion performance from C<1lalysl deactivalion due 10 pOl"OnJrlg is nul possible 10 re.,to, e w;lhoul dTecllve cleaning 10 remove the deposils, or evcnlual replacement. )- Catalyst fouliJ)g: The surface me" polenlially oxposcd 10 the**rc~g(."Tlt** (ommonia) and nitrogen oxides in lhe flue gas**t~n** bccome fouled w;lh flyJsh ur ,ulfllr-relaled compounds_ The presenoe ofexCcss calcium oxide", Ihe presence ofsulfur in lhe flue gas can jonn a calcmm**~ulf"le** surface coating Ihol Con be eXlremely densc, Tll,,-,king Ihc pores ofthe c<,llllysL**Pro~e"sive** 10"" ofSCR NOx**r~d\lclion** perfnrm"nec from calalyst deaelivation due to fou]inl\ is diJIic\l1l10 re"lore withoul dTcclivc cleaning to remove the deposits, Orevcnlunl u-placement.

SCR lcehJlology**],n~** boen inslalled on numerous eo_l-fired ulilily boiler meililio, around tbc world nnd thc,c "re " I"rge numb"r ofmanufacturers lhal m,uke! lhe onlalysls_ Tile queSlion i, ",hclher SCR is a 

# i;·

BUIlL' & Md)om,dl At-1G Minnkul',lPOWl., Cooperdlivc, 1"0.

### APPENDlXAI Teehn;",,1 Feasibility A,.,e"mem Delails forNOx Control Tedmologies NOx Bilef 

### An,lrsi, Study

feasible lechnology for a unit firing North Dakota lignile. There are scnous concerns whcther insl"llalion ofSCR leehnnlogy On " North Dakola lignilc"fired unil ean be successful, cspeeially in a convenlional "hOl-side, high-dusl" configuralion_ Thc effectiveness oflhe SCIl proccss is highly dependent upon the abilityofIhc nitrogen oxides in the nue 

### gas being able to eonl"Cl the aolive siles wilhin microscopic pores orthe catalyst in lhe presence ofammonia reagent with minimal interkrenee from conlamimmLs.

A recenlleohnic.,l puper "A'h and Mercury Behavior in SCR Calalysls When Firing Subbituminous and Lignile C""ls" by the Energy & 

### Environmenlnl Rcsearch Cenler (EEIlC) ofthe University ofNorth D"kol" was puhlished in lhe FebTllary 2005 issue ofFucl Processing Technology mugao,ine"_ This paper summarized Ihe resuhs ofSCR 

### slipslream te.,tmg al two PRE-rITe,1**p]an~'** 

### and one Norlh D"kol" lignilefired powcrpbnt. The evaluation incloded delenninalion ofimpacls ofa<h on SCRplugging and blinding. Flue gas WaS isokinelically exlnleled from lhe convective pass oflhe hailer upstream ofthe air h"ater. Pressure drop across the calalyst was measured during lhe initial two-monlh teSl 

### period, and lhe two conseeulive two-monlb leSl periods following lhe**ini!i~llrial,** 

### while holding fluc gas flow and

,**"~~empernturcs** 

### Constant. Ammonia WaS 

### injecled dOWIlstream ofa screen, ul'-,tream ofa flow stmighlcncr

c

### -and air pulse scclion. Compressed air**w"~** 

### i'liected ahead ofthe reaclor, and was 

### periodically pulsed 10



### simulate sootblowing to minimize ash deposit aecumulalion_

.This slipslrC-llm SCR lesting examiTIed the significanee ofash accumulations on SCR calillysl on botb lhe macroscopic and microscopie levels. Very small flyash particles ",ere found bonded logelher 

### by" matrix ofsodium-, calcium-, and sullur-rieh materials, likely in lhe fonn ofc"lcium sulfale. North Dakola lignile coal contains mauy alkali and ali<aline--earlh clemenIS,**~nd** 

### suIfur. The firing oflignite coal which produces fine ( less lhan 5-/tm <liameler) l1yash particles creates condilions lhat enter th" pores (IfIh" catalyst, rc,ct with SO, 

### in the flue gas, and form sulfates which bind olher ash particles into lhe matrix.

As poslcd On Electric PowerResearch Inslilule Inc. 

### 's (EPRI's) website regarding the impacl ofeoallype
on SeR 

### calalysl 1ife and penorrnancc, a recenl EPR! 

### sludy'" produccd field dala 

### analyzed from an 

### ''InSitu Mini SCRReaclor" system installed in 

### a typical ''!ligh-dust'' location al seven differenl lesl sites, inclucling four firing PRB coal, one firing Texas lignite, onc firins high_sulfureastern biluminous cool, and one firing 3 

### PRE/easlern bituminous coal blend_ ·!he PRElbituminous coal blend lest was performed**~t** 

### ArnerenUE's Sioux Slillion, on one oflhe lwo 

### 500 MW cyclone_firedboilers_ This sludy found Ihal Ibe cyelone unit firing lhe PRBlbiluminous coal blend exhibiled the fastcsl ratc ofcatalyst activity degradation. Also, the higher deactiv.lion rates seen at this SilO were due lo 

### economizer exil nue gas

Minukola Power**Cool"'rativ~,** 

### Inc. AI·27 Bums & 

### McDonnoli**NO~** BACT Analy.,;, Siudy i\T'T'ENDlXAI Technical Fea,ibilily Assessmenl DeLail, rOTNOx Control Teoh"ologies**I~mp"njl"r~"** bcmg >l!,'11ificanlly high" Ihun nl**Ih~** other Sile.,. 

### Acomrariwn of

### U,C Texas lignile and**on~** ofthe l'llli-fired sHes wilh Iwo differenl catalysis, deaclivalion WHS mOre 

### n funelion oflrace**el~m~nlS** in Ihe [Jut**ga~** unu flyash Ih"n Ihe "pccific c"wlysllype Or formulation.

Norlh D"kol" ilgnilc prouucc""n "sh th"1 i> vc-ry >Iicky and**CT~"I<:S s~v~re**  a,h depo,il;on**prohl~ms.** There**hav~** heen l\0 inslallatlOns ofSCI{ systems (filII-seale) on unils lhat fITe Norlh**D"ko~,** lib'llilc. A Icchnioul ''"S''"mcnl wa,; eon,!<wled for 1l1e iTl,;lalloliOJ\ ofSCR lec1mology on a North Dakola ligLlite uml. ln orueT 10 further cvalualc Ihe fcaSlbihly ofin>I"lhng" convention;!1 SCR**~ySlem** OIl a Norih Dakol" lignLre fired unil, the Energy & Environmenlalltesearch Ccnler (EERC) "Ilhe**Univ~TSily** ofNorth DakoLa wa, eon,ulled. EERC has exte",ive experience Ulve'l;galing lhe deposilion characterislics of Norih Dakota**lignil~** a,h.

Tedmical difficullies anu anlicipHlcu operalmg problems thai arc**"mCbolv~u** w,lh TI'&pc",llo imlalling convenlional SCR technology al Millon R. Young Stalion include lbe imp"ols ofcTOsion, ,evere ash deposition, and "popeorn ash" on the oatnly,L According the EERC" study (""e Appendix 

### il), '1he mOSI >ll;flificunl problem,**Ih~** Iprohibillhe**,uc~C$\ful or~rntion**  orSCR cnLnly.'l' LO lignire eoal " the rormation oflow-lemperature sodium-<:alcium-mab'lleaillln sulfales "nd pho,phalc" Ihal will form on Ihe "mf"ces or' calaly,ls and the earryover ofdepo,lls Ihat will plug Ihe calalyst openings, Tesulling in inereased pres..,u'e drop and decreased etfJcieney". For the,e reowns, aprliealion ofavailable convenl,onal hlgh--dusl SCR kohnology is oonsi,jere<l Leolmieally infeasiblo lOrMillon R. Young SLalion Unit land Unir 2 hoiler>;. These concerns oan be divided inlo four categoric,

..bch c"legory is addrcssed below. An cxplanalion or the faclors lhar make eonv<:JIlional SCR lechnology infcasible for Ihese boilers follow",

1. A,h Deposilion: Norlh DakOla hb'11ile conlains a vaTl"b1c .n(l eomplex variety ofinorganie compoun,],; Ihal conlribule lO a,h depO';lion. This fno]**prod"e~,;** a&h wilh**,~vere** del'0silion eharaclcTislics lhal ore nol Iypical wiLh olher coals. When cxposculo the hc"1 ofIhc combustion process in"de the eydone burners, the majomy or ll,e rud ash**h~"ome.<** molten and flnw:; into Ihe bOllOm onhe flJnJoco. A**.,ignifie~nl** portion oflhe fud nsh is enlra;n",l inlO the**nu~** go,; exiting lhe cyclone barrels at high velocity, wheTe it comes inlo conl"cl wilh lhe lower fum"ee waterwalls. The porlion lh.l is curricd wilh Iherio,ing IIue gas**~oob** and SOmc is d"f'Osilc<1 on he"t Imn,fcr suTfuec, in the**upp~r** fum"cc .ml boik, conveclion pas>. Ash depo,ilion on heat transfersurfaees is a subslanlial p' ohlem for ulllL, lhat fire North Dakola lignile. The problem is
so ,eve,e aI Millon R. Young thallhe Unil I ho;ler rllOsl1Je shul down nl 120.dny inI<:rv,,1s [0

Bum, & McDonucll AI-28 Minnkol' Po"'e, CoOp,,,.llVC, Inc.

### APPENDIX AI Tcrbnic,l FoasibilityAssessment DClail, for**NO~** 

### Control Tcchnologies**NO~** BACT

### Analysis**~ludy**



### a]lo", for cleaning ofash deposits from Ihe boilcr healtrnnsfer surfaces in order 10 reslore r"asuIlllblc fumace exit gas velocilies lind lempernlUI"S.

Sodium lS a signifi"an\ contributorto the ··slickines:;" ofthe ash pro<!ueed from firing Norlh Dakol;] lignite. Sodium contenl ofthc lignite ash av"rngcs approximalely4.4%, and can nearly double this value for Wme oftbe lignileproduced from the**Cenl~T** 

### mine_ PRE coal lypically avcrages around 1.5% sodium conlenL Boilers firing North Dakota lignite typically have. 2.5%**high~T** 

### heal rale (million Bill perkilowatt ofelectric gencralion) than a typical boiler firing PRE coal, thus ICquiring more heal input and firing more fuel permcgawalt ofelectricity oulpUl. A cyclone boiler ruing Nonh Dakota lignite also converls approximately 50% ofLhe fuel ash to nyash, compared wilh 35% conversion ratc for PRB co.l-fired cyclone boilers. Overall, Lhis results in an amount ofsodium**~"TT1ilLed** 

### from a cyclonc boiler firmg NorthD-dkuta lignite of approximalcly**7.31b<!M~-hr** 

### compared wilh 0.9 lb,.lMW-hr for a PRB_fired cyclone boiler.

## (-~ 

# i'a;0-

## ;~.:; :'(, I 

# r t',

## ~< t

## r4r-·-~1 ,

.... -'

__•.. The calalysls 

### in coal-fired boiler SCR "",cion; are highly susceptible ).0 

### ash. deposilion_ 10 a lypical ""nvention.l high-du'l SCR reactor, lhc flue gas !Y]Jical1y passes Ihruugh two 

### to four layers ofcatalyst modules. The c"lnlyS! modules have numcrous narrowpas",gcs 10 provide inLimal" comaCI between Ihe flue ll"s, ammonia and catalyst The clearance (pilch) in thesc 1'''-'--'<3ges is typically 6-10 millimeters. A Iypical calalystlayer is approximately I lo 1.5 meters deep_ The calalysts in "<lUl-flred hoiler SCR reactors mUSI be cleaned frequco,ly using soot blow"" andlor sonic horns. This is lrue even on illlils firing fuels thal do notpruducc slickyash lhal contribulcs to ush deposition. A>;h dcposilion on the calalysl in a high-dusl SCR appliealion would be severe fora uni, liring North Dakolu lignile.

Sulfur

### in thc coal is oxidized dunng excess air combustion to form sulfur dioxidc (SO,). nnd a small .mount ofsulfur lrioxide (SO,). Some oflhe ammonia-bnsedrcagcnl injecledupstream of lhe SCR reactor will combine with So, lo form ammonium bisulfate. The CatalYSI in 

### the SCR reaelOTwill also oxidize a portion oftlle SO, lo SO,. Excess unreacted ammonia**r~<Ig<:m** 

### carryover (Uammonia slip") from the SCR rcactor will also reacl wilh Lhesc sulfuric acid compounds in a similar fashion. The deposition eh"rnelcriSlies for a unit burning North DakOla lignile will C"<Ile difficull-lo-remove ash dcposils nnd plugg.ge ofa conventional high-dusl**cnlalys~** 

### and increase the probability Lhat Ihe air prchcalcr downstream and fluc ga, duclwurk win bc pronc LO accumulalions which could be severe. High-dusl SCR performance and calalysllifc

Minnkota PowcrCooperalive, Inc_ AI·29 

### DllIns & 

### McDonnellr-IUx HACr Analysis Smdy APPENDIX AI TedUliool Fcosihilily**A.~,c"mcn(** Dcloil" lor NOx ConlTol**Technolo~ic.,**
will 

### be ,cvcrely impacted, U is anticipated Ihal a high--<Jusl Sell',**ca~,lyst** lifc will bc shorlcncd from J-6 years (lyrical) lO as linle as 2_12 monlhs, requiring ""'ended, freqnenl oUlages for rcpJacrmcnl.
Hol-,idc "iT pTchealers me suscepl,ble 10 fooling. 

### Tobol"r air prc hc"lcrs originally ,upplied wilh all cyclone 110ilers alw loleratc mu<1cmle duslloadings, since Iheir heir-hi and .,ize make Ihem ,hffieull lu m"inlain clcanliness, Leak lighlncss ofIh,- "iTprehc"lcT IS imporlanl on cyclone-fired boilers w,lh relalively hJgh forced drafi: iim discharge (combllslion air supply) pressures, A highdust SCR installation will be prone lO aJr I'reheaIertube ioulmg and I'luggage, requinnJi e'<lended, ircqut-nl uul"I,'Cs fur ckamng.

2. ·'Popcorn Ash": A second con,ideration in the "pplication ofconvenlional high-<lusl SCR technology on a ligniIe--lired "nil is Ihe 1'01enlial ofthe SOl reacmr caruly,tl'lllggage re,ulling I,om carryover of"l'opeom ",h" from Il,C I>o;le"- nOJlers iiring Norlh D"kola lig";le h"ve ,cvcre problem,; wilh ",h oqlOsilion on boiler smfaccs. Norlh Oak"I" lib'llilc h"s a high propcnsily 10 form d,·po,ils on Ihc bOller's furnace and convcction p"" fIreside ,udaees. For hgnile-fired umts, the hoiler'., heal lransl"r sul'isce' 

### .om, he cleaned by s""lblowing and Olher method" (",I;, waler lances) Ireqll"nlly 10**m",n(~in** SOli.iaclnry holler oper-cilloo Some ofIhc removed dcpo:;ilS Tc1ea""rl by Ihc clc"ning "clion wilhin Ihe boiler and COl1vcciion pH&<:' form ·'popcorn ash", whleh wlll bc lTllrnillCd in Ibe flue gas. Cany**OV~T** ofb01 kTash deposits wil! conllibute 10 pluggage ofthe ·'popcorn

..,h" sereen ahead ofIhe top layer oiSeR reaclOr CaLaly'L This Can call,e diSlOl'liOnf. in gas di<lrihutlOn ("channeliLlg") lhmllgh the SCR r""clOr, which will agj,'r.,v;,le erosion in Ihe high vcloelly arcas ami ineffcclivc perfor","nee ofIhe**~"t"IY'I.**
3. Temperature: A Ihird issue Ihat impacls the feasibility ofinslalling high-dust SCR lechno]ogy OJ\ lhe North Dakola 1ignile-Jired llnils is**"al~** lyst ope' aling temperature. TI,e perJormancc "fany 

### SClt cululysl is highly clcl'endenl on Ihe lempcn,lurc "f**Ih~** flue gas passing Ihrough Ihe reaclor, Typl"aJJy,;, IcmpcTalun; of600

- 750 deb'rees F is Tequircd lu obl.in salisfJclory operalion ot'an SCR reaclOL Operation ofoommonly supplicd cnLaly,t SllJt:lblc 

### lor a high-{h',1 SCR Tcaelor al Icmpcn,lures above 750 degrees resuUs in severe and mpid delerioratiou ofIhe caLaly.'l "rid SCR re,clor·s NOx emission ,eduolion perlol'mance, For bituminous and suh-hilununoll, coal_r,,,,,l uniL', hoiler Iluc**,~a,** pussing belween Ihe**cconurni~~r** o,nkl unll air**hl"I~T** inlel is**~l'I1e]'Jlly**

Bum, & MeDoJllldl 111-30 MinnkolD POWIT r-nopeoalive, h,e.APPENDIXAI Technical FeasihililyA,sessmcnlDelail' fotNOx Conlrol Technologies NOx BACf**Aoaj~sis** Slndy**~.,**

..**~._-** -. 

## .**~-** within a lenlpernturerange acceptable furconvcntional SCR cUlulysls without auditional heating
or cooling oflhe 

### flow stream.

North Dakota lignite-fired cyclonc boilers, including tho,. al Millon 

### R. Young Station, have high temperatures at thc cconomi.",'s flue gas oullet by <lesign. The highcSl g"-'**temper~tur~."** downstream ofthe cnnveclion pass cconomi:zt:r sections and upstream oflhc "irheater inlets in Mihon R_ Young Unit l's boiler are much higher than 750 degrccs,

Iligh gas tcmperatures at the air hc-ater inlet arC required to produce 

### the high air temperalures (700°F) needed for the pre-combuslion lignite drying system, ulo"S wilh primary and secondary combuslion "ir supplied to the cyclones. Such air preheatcr ;nnmgemenL, and c"pabililies have**be~Tltaken** into account in the de.,ign OIlhc North DakOla lignite-fired cyclone boilers. Reducing this high gas ",mpernture to accommodate conventional catalysts for a convcmional high-<lust· SCR**r~-aClor** would result in prc-combuslion air tempcrntures thaI are too low 10 provide

..**_.~~lisfactory** <!..TY!ng**a.!'~** rapid**~~~~on._?~~":e_h!gh-moislnre** fucl. This will ,e,;ous)y impact reliable combustion, ,lag formation ancl tapping in thc cyclone burners. Consequently, it lS not fcusible tel medlfy the MillOn 

### R. Young Unit 

### I's boiler 

### 10 opernte wilh the lowereconomizo.."T oullct flue gas lemperaluTC,
C.talysts for a convenlional high-<lus" hol,-side 

### SCR 5)'.,tem havc nOl been installc<l nOr successfully demonstr"lc(1 in 

### a lull-scale installation ofan operaling soli<l [oeHired unitlh"t 

### are designccllo conlinuously Opl,"te al the high lcmperatures (above 750 degrees F) lhat exist between the conveclion pass economizer and air heater on lhe Millon R. Young Unil l's boiler.

4_ Erosion: A final considcmtion on whelherhot..o;ide,**high_d~t** SCR technology can be succcssful
on a North DakOla lignite-fired unil is lhe potenlial for**ero~ion** oflhe SCR calalyst. North Dakola lignite supplied from lhe Cenler minc has an avcrugc fuel ash contcnl of 10.5%,.Jtd can have an ash contenl upto 

### 25.5 percenl_ 

### PRll coal fuel ash content lypically averages approximalely 

### 5 percent. As previously staled, a cyelone boiler firing North Dakota lignile converts a sign,Jicanlly greater amount offlyash than a PRE-fired cyclone boiler. 

### OVCT1!II, lhis results in a flyash oUlput mle from a cyclone boiler firing North Dakota lignile ofapproximately 

### 83 lh.,/MWhr compared wilh 

### 21 IbsfMW"hr for a PRB_fired cyclone boiler. High ash eunlenls in the flue gas stream can result in physical erosion ofthc calalyst. In addilion, effective on-line cleaning oflhe

Minnko,a Power Cooper.rivc. Inc. At_3t Burn' & McDonnellAPPENDIX Al Tochnicol l'eaSlbililyA.,,",,,,menl Delails for NOx Control Toohnologies**high-du~1** c;ll"ly,1 will likely**r~(l"irc** stc"m oreumpressed mr soolblowing. Cle'nint: cydes of Ihe ealolysr will be required much more frequently lhan a typJcal convenlion,,1 SCH. in"(.llalion due to Ihe ",h dqx),i(ion**ehar~~(LTislies** ofthe Nor(h Oako(" Iigni(e**~nd** rhe expectoo buildup an<! plll!!".gage re.,ulrirlg from lbe caroy**O~er** of"p"peom ",h". FTe(jllcnl sootblowing ,,) Ihc c;,("ly'l lo remo\'e fouling deposit" arid ;"h accumulation" will conlribu(e (0 erosion ,md dccreased ca(alySI lifc. '] here '" .wme E"rop""n experience wITh**hil~h** "sh brown eOill, thal calalY"l manuf"c(mers WJIl he abk lO umw upon. ·n,i.,**e.~pcrien"c,** however, 

### ""II not be direcrly 'pplic"ble to lhe.,e Unite,,1 St,,(cs um ls beeau.,e oflhc severe deposition chaJ<lcleri"ies of(hc North Dakol1J lilllll(" osh comp.red (0 brown eo"t.

The EPA's N,sR**M~nllal** ,I"lcs (hJ( 1,,1' n lcchnology (0 be k"siblc ,( must "av.iloblc "nd ;,pplJcJble". SCR lochnology i" "n JVJilable technology which hJ" been instJlled on numerous powel'jllam faeililie, around (hc world "nd lhere al'e a l;Jrge number ofmanufacml'er.' lhal marke! the technology. The q"e'lion 

### is whclher SCR (echnology" '·applicable" Ii'r a unil flrinR Norlh [)akOI;,**li~ute.**

In accordance with EPA·, NSR Man",I," (cchnology i" ""pphcablc" 

### if Il has htL"Tl msl<llled on a ".,imil"r
urnl". HOl-side, hIgh-dust ,sCR 'cchnology hoo been I'el[olll 0[\ coal-lir",l "IIlls fealuring**oyc1"n~** bOllers. However, there are no ,sC.R m,lall"llOns in**op~mllOn** Orpl;Jnnod On unit, (h"t include cyclonc burners firing North Dakota lig"i", wllh severe "logging ,mu foulmg 1"ndcn",C' combined wilh ",ch hIgh boilel' economizer outlcl gas lemperatures (over 150°]-') rcquired for high-mOlslure 

### tue] prc-dry;ng sy"(ems anu (ububr "irprehe"lers_

The EJ'A's N,sR Manual abo sl"tes a tec1mology m"y bc ,lctemum;d (0 be nOl applicahle

# ,f'·" ledm;cal a"",---ssmcnl**~onsidcTing** physicJI, d,eml";l! Jnd engineermg pnllciples andlor empiricJI data showing Ih" ",chnology would not work on the emi"ions unil**und~r** review or Lha( un"oh'"blc (edmical dJijicullle, would prccludc (be "ucce""lul dcploymen( orthe technique_" Tn (hi.' ,sCR lechnology apphcntion, i( appeal" lha( a faeili ly ulili(y powerplant llring North Dako(" hgnilc wOllld experien"c extended lime delay" or he requirc,! to devote signilioanl intcrn,,1 resource" and engJge ontside rescm"h, followed by extended field (riJI" to leam how lO "pply a conventjona!l,igl,-dust, h01 -side SC'J, (echno] ogy on 'J stich a Iud sonroe.

Based upun lhi, lechnical**a",e.\.Sm~nl** that looked allhe \'ariolls de,ign ilnu**op.ralion~1** i",ucs as.,ocialcrl wirh the 1Il,tJllJlion ol"hol_",ue, high-dusl 

### SCR teclmology on a Nm(h Dakota lib'Ilile-fired sle.m_ok"lric

Al_.12 MilUdwla Power rooper.llivc. Inc.APPENDIXAl Technical Feasibility A",e=tDetail, for NOx ConlrolTechnologic, NOK BACTAnalysis Srudy

generaling unil, lhis conlrol oplion is considered technically infeasible for Unit l's**boil~T** al Millon 

### R. Young Stalion.


### A.1.3.4.2' 

## low·Dust Selective Catalytic Reduction (lD-SCR) Low-cluSl SCR (I.D l>CR) lechnology could**potcnti~1Jy** he applicable 10 North DakoLa lignite-fired boilers lor NOx emission control. Low-du<I SCR refer< lo the location ofthe SCR syslem dUWIlslrcam ofa**p~rticolate** colleclion syslem, such a, an electro,tal;C precipirnloror a fabric filter. IfIlle low-dusl SCR is dOWIlslream ofa hoi-side eleclrrn;talie precipilalor and prior to the air**prehc~ler,** nne ga., reheating is unnecess"JY. TIris hagbeen the prevalenl fonn of**altemaliv~** retrofil SCRs in the Uniled Slalcs fur coolfired utility boilers. 'rherc arc len known hoi-side low-dust SCR inslallations (willloul flue gas reheat) opemling in the Uniled Slales ag ofJuly 2005. The

. ..., are listed in Appendix A2. Ifapplied lo MRY Slalion Unil I '.' hoiler. lhe low-dusl SCR equipmenl would be downslream ora cold_side electrostatic precipitator, nue gas reheat prior to the 1.0 SCR reaclor inlct would be nX]uired forproperNOx erni&,ion reduclion pcrfoITIlllnce.

For 

### ucold_side 1.0 SCR, the ESP oullel flue gas passes lhrough a low-dusl gas·to·gas heal exchanger 

### (ill GTG-HE), prior to passing lo the low-dust SCR reaelOr. Aller the 

### LD GTG-HE, Ihe flue gas will travel lhrough lhc new duel, receiving hot nue ga"es from a direel-fired gas burner or set orhigh-pressurc Slcam coils, leading lo an ammonia injeelion**b";~,** lurning vanes and Lhcn inlo the I.D SCR reactor. The flue gas eniding lhe inlellolhe 

### LD GTG HE is expecled 

### [0 be near the air heater OUllellemperalUre (330-J40"F) in a cold-side 

### I.D SCR application. The supplcmc"1Ilal heal added dOWTlSlream Oflhe 

### LD GTG_HE can be 

### SUl'rlied from high lempernture slearn coil., (indirect beal e",ehange) or directly from naturdl g;,s-fired duct hurners. The flue gas must be heated [0 a minimum ofapproximately 600"F for lbe 

### ill SCRNOxammonia reaction lo be effective. The LO gas-m-gas heal exchanger is wed lo recover pari ofthat supplied heal, prior 

### to exhausting to Lbe FOD syslem (ifapplicahle) and stack. The usc ofrol<lry regeneralive-lype heal exchangers has been applied in European 

### LD SCRs. With this design, lherc will 

### be leakage helween the untrealed**~nd** lrealed gas streams such lhallhe eX;l flue gas has higherNOx concenlralions lhan lhe 

### LD SCR outlel gas. TIle'direcl-fired flue gas reheat ducl burners will also**"r~-~le** No", emissions, which will udd lo the amount emilIe<! Ii'om the boiler and input into lhe I.D SCR ,eaclOL The LO SCR reaclor, GTG 

### HE, and conneeling**~uClwork** will increase lheprcssure drop lhrough rhe nue gas syslem. This nonnalJy require.., an induced draft fan UPb'f1lde or a boosler fun addition.

MinnkOla Power Coopera';=, Inc. Al·lJ Bum, & McDonnell!'lOx BACT Annly,;, Siudy APPENDIX AI Technl""ll'e"ibiliIY Asse"menl Velails for NOx ConlrolTcchnologio'

TIlt I"dun; IhJt mJke l(lw-dusl SCR leclmology infeasible fOl' Il,e Millon R_ Young; Slation Uni[ J':; boiler with exi'ting pnrticlIl"le collecliOIl vi;1 c!ce[roslnlic prcclpilnlurs "rC as follows:

• CalalySll'uuJing 

### muJ Deactivation: An exi'ling electrostJtJC rlecipitalor UpSlre"m ofJ low dusl SCR reJclor will still expo.,e Ihc "alalyst In 

### 11", acid**gn~** conlenl ;md finc p"rlicul"le conl:lining; trJce metal.' and Ihe l\lgh nJbli mmeral conlcnl ofIhe entrJined IJgmle {]ya,h**nollemoy~d** by Ihe ESP upSlre"m. Ahbough Ihe 10lal a,,":mnl ufllyssh canyovcr i"IO the LD_SCR**r~-Jclor** '"**~""atly** reduced compared wilh a hlglHluSl dc:;]!,,,,. illS Jmioipolctl Ih"llhc low-dllsl SCR cotolysllife will slill be**unacoepl,~bJy** 'hOrl. TI", small pOrlicle flY".,h passing inlo the reaclor will be suffioien! 10 c<mse pluggagc ufIhe ealalysl pures, resulting in dcacllvat;on ofthe ca,al)'M. TI,e flrillg orJiWlilc coal produ,'c' flne (less**Ih~n 5-~lm**  diameter) llyash particles, which are alSllltIlSllJkdy 1(> be rcmoved by the exisling particulate coneclion cXluipmcnt (e.g. ESP) upslre"m ofa ]ow-uusl SCR. Thi., erc.les coodition., Ihot allow lhe.,e ,mall fly",h partIcle., lO enler theporcs o[lbe cJrnlysl, react wilh 

### SO, in Ihe J]ue gas, 

### amJ furrn sulf"te, wh,ch bind olher ash parlicles inlo a malrix ofsodium-, cakium_, and sullur-rich moleriJls (likely in a lilTTn ofe"kium sulfale). Onee sud a matrix form,; "'ilhin Ihe cal"lysl, il can he exlremely lenaciouo ;m<l difficult 10 remOvc.**On~** c"laly,1 "emlor's has slaled iIis Iheiruexperience [h,'l low-tlu'l c"I"ly,1 is mOle d,ffl",dl [0 clean Ihan that froOl high-dnsl" In. Low-du>l 

### SCR pcrfurmonce and calalysl life could 

### be severely negalively impacled. Shurtened Iitespan, ofLbe LO SCR calalySI will "equlre premalure, extended, Irequenl oul,,);es furreplacement.

• Sile Space COI\<lrninlo; The inslall,lion of" low-III"1 

### SClt systcm 'vith Due g"s n:heal require, 0 sub,l"nli,,1 amuunt ofspace lor in';lallalion and opelalion. A low-dml SCR syslem wll1hkdy use a rcg;cncmllvc £"s-Io-gas heal exch"nger (reheaIer) In Iaise Il,e lemporalure ofIbe nue P)-l' "t Ihe SCI{ inlet. A GTG IIE win lmn,fc, heal li'om lhe llue

### ps al Ihe SCR re"clur outlel 10 Ihe flue ga.' ellte"'n" Ihe SCR renClor in unb [0 mi,UmJze Ihe supplemenl"l SCll energy usage. Thc l;os-I(I-ga< heal exchange, diclalcs Ihe foulprillt (IfIhe eold-,ide Jow-uusl SCI{ system_ SI,aee '" required [(Ir lhc GTG 

### HE "nd fur duclwork in and on! uflbe rehealel. Sulliclenl free space around Ihe reheMtt and SCIt is al.'o requiled [or mainlcnonec.

The"",;] around Unil' I and 2 

### a[ lhe M.R. Young slmion 

### is eXlremely conge.,lcd in Ihe Jrea, wbere 10w_duS! SCR <ySlemo must belocaled. 

### The siluation is particulJrly severe fur Unit No.2. Equipl11enllhat imp"cls Ihc fe"ihiliIy ofinstolJing J low-dusl SCR sy.'lem un UniLs 

### I a"d 

### 2 includes Ihe Uuil2 absorbers, lJni12 nue!l"S de,ulfuri7.alion (I'GD)**~cw"lcrin);** cquipmenl, ny ash haudlingequipmenl, fuel storage a"d I"msfer equlpmcnl, 'I"eks, fmlS**an~** ductwork_ II would l,e eXlremely

DUnl' & McDomlcll Al·34 MilulkollfPower**('O{Jp~ralivc,** Ino.APPENDIX Al Tcchnical Feasibility Assessment Details for NO" Control Technologies NO:<. BAC[Analysis Study

disruptive to the continued economio operation ofbolh boiler>; 10 relocate all the memioncd equipment 

### to Greale space for lhe low-dust SCR systems alllle M.R. Young Stalion. Slades, fans and duclwork and lhe Unil2 FaD system oannot be readily relocated <Iuc to adjacent structures and the need 10 conlinue operation whilo constructing the retrofit installalions_ The fuel handling equipment includes a coal stomge bam and the main conveyors snpplying lignilC 

### to lhe units. Relocating the coal handling equipment currently occupying >paGe needed for lhe low dusl SCR sys\Cms would be quite difficult given the site configuration. It is conceivable lhalthc ny ash equipment located west ofUnit I could be relocated to provide some ofthe "pace needed for the low-dust SCR_ However, the availability oflhis space is doublful, sincc**~voidjng** the likelibood ofsevere SCR calalyst sulfutc fouling will require a new Unit I FGD syslcmto be installed. Ifanew FGD system is inslalled for Unit I, lhe FGD syslem wnuld need 10 occupy !.he space thaI can be made available by relocaling ash handling equipment This space subsequently would nol be avaliable for a low-dusl SCR syslem.

Based upon a teclmioal**as~sment** lhal looked at lbe various design and Of"''''-tional issues associaled

. c'·, wilh_lhe-instaliation_oflow.=dust.SCRtechnology_on_a_Nor:th_D_aJmJ.aJimiJ01Ll<':tS!=e_am-dectric

_ - - ----------- gen",atingunit, lhis oontrol option is consideredtechnically infeasible for the Millon R. Young Station Unit l's bOiler.


### A.1.3.4.3 Tail-Gas Selective Catalytic Reduction (LD-SCR) A tail-gas (TO) SCRis a low_dust SCR system where the LD SCRreactor is installed downstream ofa FGD scrubber_ The FGD outlet nue 

### gas passes through a gas-to-gas heal exchmigcr (GTO-HE), prior

### to passing to the !ail-gas SCR reactor. The nue gas will trnvel throughnew or modified ductwork kading to
an ammonia injection grid, turning vanes and then into lhe TO SCR reactor_ The TO SCRreaclor, OTG HE, and connecting duolwork will increase the pressure drop through the nue gas system_ This nonually requires an induced draft fan upgrade or a booster fan addition.

A schemalio graphic diagram for a low <lust anangement is shown in Figure A.I-6.

Minnkola PowerCooperative, lnc:_ Bums & McDollJlellNOx BACT IInalysis Study APPENDJXAI -Iechnical Fea>ihill(yAssc>smcnl Deialls fur NOx Conl",1 Technologic, 

### I<'igure A.1-6 TlIil_Gas 

### SCR ArrJlngemcnt 

# Low Dust Arrangement 

# CD Steamgenerator 

# ® Regenerating heal exchanger 

# ® Air**(~1** 

## F.lectrostalic precipilator 

# ® 502

- Scrubber 

# ® Burner! Heal Exchanger 

# 0' 

# -7.) SCRReactor 

# @


# -**"~~>./,**

# ti~ l;/"- I , ....**,k~/ ~v"**  

# ,!lY" 

# ® "**-~',** 

# 1f"@t,f"y@ ® Catalyst 

# ® Vaporizer 

# @ AmmoniaJ 

## Air

- I\Iixcr 

# @ Ammonia slOHlge tank 

# @ Fuel J

## Ste"m (1Igu," COplecl 

### rrmn wneemOrniorAir 

### I'ollu,""n Control lllefTlrurOJ
The tlue gas Ii-om a wei ron scrubber oulle! c"lering U,e inletto lhc gaS-\O-g.lS hear cxeh"nger is expecIcd lo be "e"r lhe ,arurnlion lemperallirc (14 WI') in a cold-side TG SCR applicalion. The supplemenlal heat addcl! downsIreatn oflhe '['G GTG-HE enn be supplied from high leml'crnlure sleam coils (indireclheal exchange) or direelly Ii-om nalurnl g,as_lirccl duel burners_ The flue 

### ga' musl bc healed 10 a minimum ofapproximately 600°F fur the TG SCR NOx- ammonia reaction 10 be effcclive. 'lbe TO gas-tn-gas heat exchanger is lL'<Cd 10 r""overpnrt oflhat supplied heal, prior 10 exhausling 10 the Slack. Wilh a rolllry regenerative-lype gas-lo-ga, heatexchanger, lhere will be inlcnlalleakage hClwcen lhe unlreated and lreated gas Sireams such lhat lhe slnck exilllue gas has higherNOx concentralions lhat! the

Bums & 

### McDonnell IIJ-J6 Minnkola Puwer Cooperotive. 

### Inc.APPEND1XAI Technical Feasibility**A,,,,,,,men~** Dclail. rOTNOll ConlrolTechnologics NQx BACTAnalysi.**Slu~y**

, 

# .. TO SCRreactor oullel gas. Using direcl_fired flue gas**r~heal** duct burners win 3100 creale NOx emissions, whioh will add to lhe amounl emitted from lhe boiler und inpul into the TO SCR reaclor_

There is limited technic"l information pUblished in English for co"l"fired steam-electric g<:nemling units (SEUU) wilh 10w-dusilloil-gas SCR !eehnolob'Y in npplicalions requiring full flue gas reheal prior 10 Ihe**r~."elor** inleL There is no**e>:p~.,-jence** with TO SCRon**~;)s** Lem hituminon<;, we.,lem ",ubbiluminous coul or lignite-fired SEOUs in Ihe United Slates. As of 1997, lhere was one low-dusiltail-gas SCR on a 220 MWe Oerman eydOne-fired hoiler with a 

### 1988 retrofit installation_ This boiler W"s reporte<lto he opcmting wilhout combustion control" Or FGO, burning low sulfur, low ash, moderate moislure bituminons coal with an avcrage pre-SCR NOx emission role ofapproximately 1_07 IbfrnmBtu, and wus mceting :l 30-d"y rolling avemge emission llmit ofapproxima,ely 0_16 IblmmHm (85% leduction)".

Millon R. Young StationUnit I does not currently incorporate any flue gas desulfuriZ>llion equipment, which would place thc Te"CIOr catalyst in a low-dust SCR configumtion, which is considered infeasible when-buming-NOlih-Dakota lignile.-A-new_FOD system for_Unit-l_would 

### be required in ordeLto avoid or.

_ _ _ _ signific"ntly reduce expeoled sulfale fOITn"tion within lhe**ea~~lyst** and g,s-IO-£us hcu!**e~ehanger** when combined with ammonia required for the 

### 1'0 SCR_ Unit 

### 2 currently employs a welscrobber which cllITeLllly treats approximalely 83% ofllte total fluc gus flow flOm the boiler. Flue gas rche.t is currently provided by the FGD bypass (i.e. wann, nntreated flue gas is mixed wilh Ihe cool scrubbed gas)_

The faotors th"l m"ke lail-gas SCll technology infeasihle for bolh Millon 

### R. Young Slation boilers with existing particulate collection via electlO<talic precipit"tors 

### are as [ollows:

• CatalyslFouling and Oeaclivution: The TG SCR reactor downstreum ofu flue gas desulfuri•.aliou (1'00) scrubber will 'Iill be susceplihle to fouling, contaminalion, pluggage, and catalyst dcactivalion.
o An**~"Xisling** cleelro<tatic precipitator (ESP) upstream ofa !ail_gas Sell. reactor will slill expnse the calalysl to fine particulate contaiuing lrnce metals and lbc high alkali mineral content ofthe enllained lignite flyash nol**r~"TTIovcd** by the ESP**upstr~-dm.** Allbough lhe IOIllI umounl ofijyash cmryover inlU lhe TG-Sellreaclor is grcatly reduced compurcd with a high-dust d",ign, il is anticipated thai U,e tail-gas SCR catalysllife will slill 

### be unacceptably short.
o The firing oflignite coal produccs fine (less than 5-jlm l1i"meter) flyash partieles, which are also least likely 10 be removed by the oxi,ting particulate collection equipment (e_g_ ESP) upstTc"m of

Minnkolll PowelCoopcmti"e, Illc. AI_37 Bums & McDonnellNOx nACT An,lySlS Srudy APPENDIX Al Tochnical FeasibililYAsses.,menl Delails for NUx Control Technologies

a TG"SCR. Hue ga" with entrained line paniculale mOiler, includil\g ,OmC involving wdium and ,ulfm-conlaining coml,ou"ds, will pass lhrough and be carricd-ovc, from a well'GD scrubbcr. This IrC<Llcd gas ,tream w1l1 carry sodium s\llfn1c**p~rlicIcs,** formed by 110mogL'TlOtl' coll(\ensnlion afler exiting llle bOller Hnd nol removed hy the ['UO syf<1em. into lhe calalySI**];,y~rs** ofthe 

## n,- SCR**r~uclor.** A dry FGD syslem followed by" f"bric Iill"r "pSlre"m ofIhe TU-SCR will slill allow sulfur-beoring nuc 

## g'" ,md fine pan,cles 10 enler the calalysL There is 'LTIO"S concern thaI fi"e p'rlic1cs P"S>lllg inlo lbe reaelor will "ee"mul.k within the**eOI~]Yol,** m,d be ,e.,isl",,1 10 rem(}V"1 by "onvenl,onal 300thlowc,-,; "nd olh"r ckming leclmolog:i",. Thi,**crealc~** comhlions th"l allow Ihese ,man nyosh p"rlicles 10 enler lhe pore, oflile calalyst, ,eact wilh SO, and/or SO, iulile Hue WlS, 'nd fonn**~ulfatcs** which bind other ash parlicle, iL1IO a malrix ofwdium-, calcium., 'Inri ,ulfur-rich malcrial, (l,kely in a fom, ofcalcium .,ulrote). Once ,uch a mal"" fonn" wilbin Ihe calalysl, it en" he cXlTcmdy Icnaciou' ami diflicuillo remove. C"I,dysl lhal is cxpo",·d 10 such**condilion~** w,ll bc incfleclive almamlaimng aueqllale aClivily upon whIch lhe performance orlhe TG-SCR's NOxremoval i, based.
o TI,e,e enlraincd purlicles will also del'o:;; On Ihc fI,S-lo-.I;a, hear exchong:cr "head 01" 11te lolil 

## .1;"' SCR**r~""clor.** Th'," ueposlllOn wiII (1CLT""'C hcal Imn,fcr belwcen lhc mcoming (cool) flue 

### ga, ",,,I lhe oUlgoing (wa, m) Ilue gu,. Soolblowers could be used 10 remove the accumulated depos,ts from lhe GTG HE, bul the SCR reaclor could 'till 8uJl"cr calalyst fouling fmm lhe deposic, dislodgcd from Ibc UTe; IIE cleoni",; eycle becoming r"""lmincd in Ihe**reh~,lt(1** n",: ga.,. T**~il-:;J'** SCll pcrforTnance ami e"I"ly"1 l;fc co"I,1 be sevcrdy negalively impacled. Shorlened life,pan3 01" lhe TG SCll calaIY31 w,ll require p'em.lure, eXlended, frequenl oUlages for replacement

• S,te Space ConSlrainls;**Th~** in"lallalion 01"n**1:lil"g~s** SCR sy:>le", willi nIle gas reheat**,equirc~"** subst,"lial**~rno\lnl** ofspace for in,tallallUn "nd opcmlion. A tml-lWs SCR "y'lem wi1l1ikcly use a**rq~l"IIcmlivc** gas-to-gas heal exch'nge, (rchealer) 10 mise the lempcralure oflhe Iluc g"' at Ihe SCR inlet. A GfG lll'. will Irnmfcr ru:"l from the Huc gas a1 Ihe TG SCR reaoloroulJel lo the senlbocd Iluc gas c'Tllcring the SCll r"ador in oakr 10 minimize lbe snppkmL"rlI"1 scn energy usage. The ga3- lo-g""**hea~ ~x"h"n~cr**  diclales the roolprint oflhe TG SCIl sysl"rn. Space is requircd for the

## on; lIE and for dUOlwork in oml uul ufthe ,cheater.**SujT,~i~,,1 fr~c**  spaee amunulhe ,eheatcr und SCR 8ystem is also required for maintenancc.

The area around Uml, I and 2 "l!hc MJt. Youog: "'.l,on 'S eXlremely eoogcsled in**th~ aT~-clS**  where TG sell 'y31em, musl**b~** localed. A Hue gil" uesulfunZilliOJ1 syslcm will be neede<J for Unit I in lhe 

# n,,,", & McD<lnndl**Al_3~** MinnkOla PowcrCool'emtive, Inc.APPENDIXAI Technical Fea,ibility A",essmeOl Details for NOKControlTccllllologie, NOxDACfAnalysi, Study

near future 10 comply wilh lhe Consenl Decree. When a new FGD system is installed forUnill, lhe FGD system wouid need to occupy !he space lhat canbe made avallable by relocating ash handiing equipment_ This space subsequenlly wonld nol be available for" tail-gas SCR system_ 'mus, the availabihty ofadequale space for all lhcnew FGD andTG-SCR system equipment and structures while accommodating**exls~ng** coal slorage andhandling needs forboth exislingboilers at Mihon 

### R. Young Station is doubtfuL

The challenges for installalion ofnCW ductwork, SCR reaclOrs, and fluc gas rehealing equlprnent and lhe lack ofpertinent experience with all aspcclS ofdesign. construction, operation and mainlenance oflai1-1}" SCRs on suchhigh_fouling coals as North Dakota lignile are significant. The flue gas oondilions thallhe TG-SCR oatalyst will be exposed 10 will crealC unresolvable fouling andblinding !hat makes successful applicalion ofthis technology diffioull, expensive, anduncertain.

The risk offailure and uncertainty ofsuoccssfully applying Jow-dust, tail-gas SCR teohnology to a

---::_'- cyclone-fired utilItypowerplant-firing-North-Ddkota-lignitc appear_subst=tiaL

Based upon a technical assessment thai looked at lhe various design and opcrational issues associated 

### with lhe inslallation oftail-gas SCR technology On a North Dakota lignite-fIred steam-electric generating unil including a cyclone boiler. this control option is considered lechnically infeasible for the MillonlL Young Station Unit l's boiler.


### A.1.3.5 Electro-CatalytIc Oxidation**(ECO~** Powerspan's Electro-Catalytic Oxidation (ECO"') syslem is a mnlti-pollntanttechnology designed 10 control emissions ofNO

### x, So,,/ine particoble, mercury and certain Hazardous AirPollutants (HAPs). The 

## Eoo'" process has two main process vessels, a barrierdiscbarge reactor, and a multi-level weI scrubber. Thc barrier discharge reaclor ntilizcs an electrical disoharge 

### to create oxygen and hydroxidc radicals ""hich lhen react with NOx, and other eonstituents in the flue gas stream. The flue gas stream lhen enters lhe bollom ofthe ECO'" scrubber where the lower loop eools the flue gas and reOlov,," a portion ofthe acid gasses [sulfur trioxide (SO,), sulfuric acid (H,SO,), nitric acid (HNO,)] produced in the bamerre.clor and oxidi7rd metals snch as mercury, with a low pH aqueons arrunonia reagent A second sCt1lbbing loop is then entered where addilional SO" NO" acid gases and oxidized metal" are removed wilh an aqueons ammonia reagenl. though at a higher-pH_ Above the second scrubber loop is an absorber seotion for absorbing fugitivc ammonia from thc first and second SCt1lbbing loops. The fmal

Minnkola Power Cooperative, Inc. AI_39 Bums & McDonneUNO, BACl Aoaly,i., S'udy APPENlJIX A] Technical Fe"slbili'y Assessmetll Delalls fur NO, ('oulro] Technol"gie<
Slep io the EC'U'" proceS" is a wet declJaslatic precipilator (WESP) which collecl" fine (XI11ieuiaie maller, aerosols generaIed in Ihe**serubbc~** "nd "ddilional mercury. An updated sebematic**rroc~ss** flow diog, am fur Ihe ba5ie EC'U'" pmccss i, shown in Figme A.I-7. 

### Figure A.1-7
- Electro-Catalytic Oxidation (ECO®) Process Flow Diagram Ico!'I "I [rom hnD:!/"""''', 'I"'.goy/.oped"",,_w/"p.'l>IEPA611111WJj 1O_]1!ID 

# ECO" Process flow

!: 

## "**""~'!'"'Jm** 

## ,. Hr,,,,,"

...**~--"-·** 

# 10",·, 'H..-

£00

### R,a,lIJ, Ablllb" v",,,,,] 

### W,IfliP 

### r..-l'roiDa

### 8",,1I'''Y 

# i

" ,J ., -, 

### .rcl**.~**

Puwerspan has been involved in an extended**HC[J~** proc","s demon.,tralion**~"ing** a 

### 28 MW Commercial Demomlmtion Unil(CDU) al R.E. Burger »lallon Unils 4&5. The ECO'" COU projecI**lr~alcd** a slipslream and demonstraled**r~rrormance_** reliability and economics for apprOximately**On~** year. Thc demonSlrnlion progmm slMCd in January, 

### 2004. NO" removal is Slalcd 

### 10 be up 

### [0 90% w,lh u claimed 

### 0.05 lb NOx1mm Iltu oull.tcondilion achievable for**lh~** fronl--end orlhe 

### ECO'" process. Further ,uslained op"mlional le,;1s orlhe ECO" COU are unMrway during lhe second and third qnancrs 0[2005.

As this i, a posI-eombuslion mulli-pollutanl controllechnology, il is elaimc<.llhat lhere is little**S~"T1sili,'ity** 

### to Ihe lype boiler 

### or bnrner>< lhat Powe"pan'. Eloctro-Catnlytie OXiu"lion (ECO") process cun be


### Bums & 

### McDonnell AI-40 MinnkQla Power Cuorermiye, Int'.

### APPENDIX Al Technical**Fca,ib~i,y** 

### A.,c.smcntneroil. forNOx Control Teclmologie, NOx BACT Analysi. Study

polellliony applied to 

### in order loreduee No" emissions. The effectiveness o[lhis ECO"'process forNOx 

### control has bc'Cn dernonslmlcd on a sliIKlream commcTcial demonstration unit (CDU) assooiatoo wilh pulvcrized fuel hoilers firing midweslern or eastern biluminous coal.
J'owcrspan'8 published dUIll from Ihe commercial dcmonstralion uni('8 performanoe ofup to 90% 

### when treating flue 

### b"'S with an inletNO

### x concCnlnllion around 

### 0.5 Ib/mmBtu. 

### Thi, wouldrcsult in" slaok NO:. emission around 

### 0.05 Ib/mmBtu.

The ECO'" process 

### ha' not been demOnSlrJlc<1 in a full-scale configumtion on anyunil, nor Icstcd in a slipstream configuralion on any boiler that 

### lires western subbilUmjnous coals or North Dakota lignite. II has al80 not been applied to emissions 

### from a cyclone-fired boilcr. Accordinll111e EPA's Drnfi 

### NSR Manual, "Technologies which have notbeen applied to (or permiUcd for) full scalc opcnnion, need nol be considered ;,vailable: an applicant should be able 10 

### purchuse Or construct a process or 

### conlrol device Ihal has already**bc~-n** 

### demonstraled in pTaelice".

There arc Dnumberofissues wiih firing North D"kota lignite lhat make Ihe applicability ofthe ECO'" proc,,",s lechnicany infcasible for 

### MRY Sialion boiler;;_ These issue, include:

• Deposils und Pluggage: Tne Dyash dcpusition charaoleri,tics ofIhc North Dakola lignile arC 

### cxtremely severc. Anything Ihat contribulcs 10 

### nyash depo,ition and pluggage within Ihe barricr rcuclOr i.' expecled 10 

### havc a detrimental impu"l On the mulli-pollntanl controlp"r[ormanoe ofthe ECO"'proec.s, and Ihns coul,l havc u serioll.' impacl on 

### MRY Stution opernlions. Thc luck of demonslnncd opernlion on trealing lbe emissions from a boiler firing coal wilh a high slagging index precludcs Ihc use ol"the ECO"'proocss as technically feasible for 

### BACT as applied lo" boiler firing Norrh Dakota lignilC.

• Reliability und 

### Availabilily: Millon R. YOUng Sialion's major planned oUlllges l"or each 'mil f\rC 

### schcduled 10 

### occur OnCe everythree y""rs. AnyNOx oonlrollechnology sckelcd as BAC'T will 

### need 10 

### operate year-round, ycnr in Dnd year oul, on a routine basis, while performing at high Icvels ofpoHutanl rcduclion. The Powerspan ECO'" 'yslem is a new technology and is nol as highly developed us olhcr mOre 

### common NO" and SO, oontrollechnologies such as SCR or SNCR plus WCl Or semi-dry flne gas dcsulfuri7.lllion (FGD). II 

### is**e~pc"I~-d** 10 

### require a full-limc, full-scale application with sustained conlinuous operation 10 

### confirm levels ofcmrc"Iltly dcmon,l",led reliabilily and Dvuilability from Ihe ECd" CDU arc acceptable lo meet !hc

Minnko'. PowerCoopem,ivc, Inc. A1-4l DUITlS & 

### McDonnellNOx DACr Analysis Slody APPEN0IXAI Toehnie"1 FOa<ibiliry M,e"menl De",il, fOT NOx Cnno-ol TedUlalogies
expeclalian ofinfrequent majorOUl"gc" ovcr lang time periods while maintaining high level, of controL

TIlLTC aTe addilium,1 faclun; lhal**m~ke** the apph"," lion oflhc ECO" procc"**pol~'Tllially** more difficolt lhan othel' eSI"blJshcd emission conlrollechnologies available fol' coal-Jired pnwel'planlo;

• TI,ere " a Jack ofexperience wilh lhc ECO" dowmtream ammonia .,crub\>er'" coproduol cry"lalhzalion and**gr.lnuli~alion** equipmenl de.,ign, ope,-a'ion, 'Illd m"inlcnance, which was not included Wilh lk inili,,1 commercial demon,lmlion lInil. The coproduci slream lh,,1 would 

# 'w, mally [<:<:<1 inlo Ihc cry"lallizalion und gnmulalioll processes was colle<ole<1 "nd tran.<[lOfled ofrsilO fOT lhi, process step during COU operalion. Because c,ystallJzalion uml granulalion of ammonium sulble from an ammonia scmbber solUllOn i, l\ol a new lcchnological proce"" lhis
was nol cOllSJdered a ledmic.1 feasibility deliciency. For inSlanee, the D"kota Ga,iIic"lion Company (DGC) in BeuJ"h, NO cun'el\tly 0pcl1ll<:s an SO, scrubbcT ulilizing 3<hmonia as a ,eageoL Following- Ihc g-eocralion ofummonium sulfaIe, OGC crystallize" and**b'TIlnulale~** a f"lili",rprodllCt Oll Hite. IIowcvcr, al MRY ,stalion, conHiderahle COSl$ would be ",currcd [or mlenm 'lorage and shipmenl ofIhe ECO'" proee", ,cwbbcr's l"IUid blccdslream unlll sufficient expe, ;cnce has "lenlilicd ,,"d eliminme(l polcnlial failurcs "nd repain; for lhe cry"I"Jlizalion aod granulal,on c'llPipmcnl should lll'roV<" 10 be unreliable.

• Siz{' oflbe baniel' reaotor: Puwcn;pan recenlly JlldicOlCd lhOi Ihey would sc"le the r<--Jetor far optimum cO,l and Sf'''cc "mlllgemenl hased upon k""uns lc.lrned from the enu p!<onloperal;on. The tlllUlbor u[incliviclu"l pa""f(es wilhm a bmTierTeac[or sized for eilher ofMKY ,slalion bOller"' maximulll flue 

### gas llow und**~as** Blream coosliruenL\ is cxpe<oled In reqmre a Oro,,- ,c",lion,,1 'lTea oom[latahle l(I h"lfofa large eleClrOMnliC prccip'I"IOr. Allhough ,Ilis I"" nol been closely ""amincd for "II .,peels ofdcsign, con,lrucliun, operalion and**main[(;n~nce,** lhe amounl ofphysic"l "pace required to hold lhc barrierreactOl' and inlet and oullel ductwork is belicved 10 nOl be uvmJabJc for polential I'elTOfil 10 MRY ,slation un; L'_ ,sile 'pace eon"trainls arc comidered l(I be a barrier 10 lc'Chnic"1 [ea.,ibiIJry forpOlenlial applicalion o[the 

### ITO'" process at Millun K. Young Sialion [or Unit I and Unil 2"s boilers_

• AddillOnal sLal,on**auxili~ry** power consumplion; The bmrier reactor, pilL< lhe "rnrnonia**~erubbcr** und wei e1eclro"I"lic prccipilalllL' addilions by an ECO"" "Ys1cm, reqUITe an increase in s[allOn

flu",.' '" McDnnncli AI-42 M',nko(a P",,"'CrCaoptmliYo, Ino.APPENDIX Al Teehnical Fea,ibilily A,,,,,,,menl Delails fnr NO>< Control Tcclmologies NOx BAC[Analysi, Smdy

auxiliJry power consumption. For NOx comml, !his includcs more horsepowerrequiredby the hoosier fan nccded 10 compensate for !he flue g35 pressure drop crcatcd aoross lhe barrierrenelOr. It also includes lhe power consumed by the dCGtrodes ofthe hJrricr reaclm ilself.

BecJuse ofthc lc"hnicai feasibility issues Jnd lack ofcommeroial availability and full-scale experience, e,]>CciaJJy on ..uoh high fouling coals, rhe flCO" 'yslem WJS considered lechnieallyinfcJsible JS a BACr ailemative forM,llOn R. YOUllg Slation for Unit 1

### 's boiler_



### ',,-. 

### A.1.4 "Layered" NOx Reduction Technologies Many ofthe NOx emission reduelion leehnologies which involve fumace or conveotion pass arcas for lheir introduction inlo lhe nue gas stream have beeu, or can polentially be, applied in combinations so as lo rcSUll in an overall higher lcvel ofremoval. Separaled overfire air, various types offud reburn, and various forms ofSNCRcould pUl<:nliallybe combined io series 10 rcduoe NOx emissions prior 10 boiler's
nue gos cxil. However, all the possible NOx conlrol1echnology combinations have nol been installed 00**,,~.** coal-fired**pow~-rplan** lS, SO actual feasibility of"orne combinations have not been demonstrated

### as viable,

.. parlioularly in considelillion oflhe special challenges posed by cyclone boilers firing lignite coal.



### A.1.4.1 SOFA Combined With Other NOx Reduction Technologies Separaleu Overfire Air can be favorably oombined wilh every othe, method in order 10 reduoe lhe amounl ofreagenl orreburn fuel required to achieve lhe resulring level ofNO

### xemission reduction. Some oonLrol lechnologies, e'1'Ccial1y eonvenlional fuel reburn syslcms, require overnre air to complele Ihe combuslion oflhe Slaged fuel admilled lo lhe upper fUnlJce. Fuel lean gas rebum can be applied wilh or wilhout SOFA. 

### as lhi, limiled JmOllnt ofSlaged fuel," inlroduced inlo an oxygen_rich almosphere down31ream of lhe cycione burne,,; and any overfirc Jir injection points.



### A.1.4.1.1 SOFAwith SNCR Seleclive non calJlylic reduclion lechnologies are post-combuslion, in-furnace NO, control allemative" lhalhave bcen inslalled in numerous boilers ofvarious dCj)igns, fuel types. wilh and wilhout overfirc air. 

## n is usually advJntageous to**~pply** overfire air so lhal lhe amounl ofohemical reagenl consumption can be minimizod iu order 10 achieve the largctcd NO

### x emission rate from 

### the boiler o"llel.

Minnkola Power Co'l'cr.lli"

.. Inc. Al-43 Bums & McDonnellNOx BACrATIalysis 5mdy APPeNDIX Al Ted"'ic"l Fea,ibilily**A.~,c** ..,menl Dol.il, [or NOx Conlrol Tedmologic.,-

Tesl< nl Cunttliv's B.L Engl"nd Slation (Units I and 1) demunslrJICd IhM SNCR C'n**de~TCase** NOx emissions as nmch 

### as 31% al full load, from 

### 0.55 10 0.]8 lblmnilltu, over and above Ihc reduolion possible 

### from owrfirc air alone (approximaloly 

### 60"10 drop, from 1.3 to 1.4 down 10 

### 0.55) in full OplTILlion. Til,s LS an overall NOx orni"ion n:r1Lrcllon of72% riom pre.rolrolil haseline".

SNell can be applied alone nr oombined w,lh cithe, the ba"io or Ihe advanoed 

# rot"", ol".,ep"rJled overli,o a" (ASOT'A) On MRY Siuliun bollcrs. An-,taging Iho cydono wilh**Ih~** 

## m" oh'1'"n'lcd ovedi,e air 10 furthn**c0ll1pkm~"1I1** combuslion NOx reduolion is "n oplional pm1 ofthis lechnique, However,"S prcviou"ly explained in the di"oussioJl ofSOFA "liemalive".this will ri"k slag "freezing" ,n Ihe barrel.' and lower furnaee. E"limaled NOx**~mission** rales for using SNCR lechniques wid, N<lrlh Dakota hgmlc eo""idercd**l'uhli,he<ll~vel~ .chl~ved**  by cyclone-fired UlliL' 

### firinC weslem ,ubbiluminou, coal, and vendor estimatc". SNClt wilh ASOFA is expecl<:d 10 rcducc NOx emissions "pproxim"tely 31 % below NOx levels predicled lor ASOI'A operation, and polenlially**5~%** overall from current baselinc level for lhe MRY Slation Unit 1 boiler wilh Ommun", ,lip limited to approximately 5 ppmvd.**Tl\i~** h,ghe"t performing ba>Je SNCR sy"l<:m is polen(ially able 10**ath[cv~** a NOx emission rale of

### 0.355 lb/mmB(u, whe"1l cumbined I"ilh lhc "dvanced [onn**of~OI'A** On MRY Stolion Unils I ooiler dLiring- operalion"t the pre--control bascline (near MeR load). Thcse**I~\'cls** ofNOx reduclion depend on rhe advanee'd [onn of ,epmaled o"erfire air lechnique 10 achieve Ihe expecled NOx ,educl,on percentage" when .ppl,ed 10 lignile-lired cyelone hOllers.

Anolher foml ofSNCR i, combmed with ,epnrJled overfire air. TIli" is eurrenlly being marketed commerclally as '·Rotating Mixing" (RoLam'I<), In lhe Uniled Stale"' ut'lilies mduSIry, Ihis has only heen upplled 10 l'ulvel'i7ed 0031-1),cd bOllers. 

### h 's rlifferenL lhall**b~sie** SNCR ill Ihal il ",eludes (> hoI ai, housler fan and II ,mnll 3mb,enl "ir

## non, "nJ injeels the ammonia (or urea) re"genl inlo lhe hi[\h-pres"urc uverfire air flow ,Iream "hcad oflhe R01<A nozzle,' oUllel.l. This mixlure i, imp"rtetl inlo Ihe bOller m lin offset fashion [rom opp",ile side' ofthe**jil",no~** "t hig-h velocilJe", with muhi-pmt nozzles locnl<'d al hlgh c1cvnlions**relali~c** 10 Ihc lOp burncr row. This vendor(Mobolce USA) oluim:; Ih"l Roillmix (rolalinl; opposcd fire 3ir OrROFA 

### + SNCR) help, lo di"lrihul<: Ihc rc"l;cnl ""rO", lhe furn,,"c cruss seclion, which max;nl;zes in-[umaee NOx reduction whilc minimizing negative lmpacl" OJ] earbon monoxide and**11},,~h** unburncd cnr!JOll.**Thre~** l"nl;c"1IllllIly-fired ulility hOlkrs burning easlern bilumlllous eoal or Illinois biluminous co.1 WC,e relrofilte-J wilb Rotamix, each achicving a NOx rcdllClion ofapproxi"'"ldy zero 10 

### 55 pe,cent beyund the levels produced by ROFA "lone, from l"e.SNCR haseline.' ,,1'0.2110**0.2~** Ib/mn,Btu d01Nl1 to 0_10 10 0.23 Ih/mm'B(u wiIhoutlow-NOx hurner,',"·",,....

Bum' & McDollndl Al--'l4 Minnkola Powor**CAoperdll~c,** Inc,

### APPENDlXAI Teelmical Fcasibilily A=smeUl Delail, forNOll Conlrol Teclmologies No"nACTAnalysi, Study

While lhis vmiJtion ofSNCR combined with separated overfire air could**pol~"!llially** 

### be**~pp1icable** 10 

### cyclone boilers, il has not been marketed 10 

### ,erve .,uch applicalions. Sinec cycloneboilers do nol require Ihe addilion ofhoi air boostcr fans for SOFA, .nu oplimom injection localions for bolh SOFA and SNCR reagefi' may nol coincide, ROlamix may nOl perform as well as, or sib'TlIfieantly better lhan, a wdldesigned combinalion ofconvcntion"l SOFA and SNCR. This technique is nOl dislincl enough rrom basic SNCR rrom fimclional and air-slaged cyclone NO" reduction pcrrol1rumce sLandpoinls to warranl imlividual consideration for MiHon R. Young Slalion boilers. Because ofa lackofcyclone-fired boiler e"perience wilh ROFA amI Rotami}[, the !DLter was considered inreasibJe and thus was not included in lhc control effeclivene.ss and <:<lSI-elTecliven"", seclions oflhe main r"-porl.



### A.1.4.1.2 

### SOFAwith RRI Rich Reagenl Injection must be used in an o"ygen-deprived atmosphere in order 10 

### effectively reduce nitrogen nxide emis..,ion,. This requires air-slaged cyclones and scpijrJted ovcrlire air operalion. The NO" c"111ission rcduelion rcag""l injeclion forRRI processes must be precisely lo,,"tcd and carefully controlled 10 

### be effcclive. Opcrolion outside oflhe required opc"TIlling ranges can even result in inerc2,cd NO, 

### emissions. E"lensive computational J1uld dymlmic (CFD) simulalions are needed 10 

### determinc lhe oplimum injeclion poinls_ Boiler operating conditions will change wilh unit load and varying fuel charactcrislies. The RRI process COtllro] syslem., mUSI be able '0 

### adjusl for thcse chunging condllions.

RRI has thc pulc"IltiaJ 10 

### provide 

### a modcrulc degree ofNO" reduction on coal-fired boilers_**D'H~** 

### from 

### B.L. England and Siou" p1anl, show Ihis ledmology can reduce NO

### x cmls,ions belween Zero and 39 perccnl beyond !he amounl atlrihu!able 10 

### overfire air syslem**operalion"~·~5~""7.** 

### During inilial demonstration l",ling ofRRI al Amerco's Sioux Uni, 1 boiler, 500 MW unil firing a blend ofPRB and midweslem biluminous coals (withoul SNCR), wilh SOFA in AuguSl2001 al a lower furnace SR of ,ppro}[imateIy 0.99, NO" emissions were reduced appro"imately 55% 10 

### 0.551blmmBlu wi SOFA only, with Z<.TO 10 

### 15% additional NOx 

### reduclion hum,RRI (down to 0-47 IbJmmBlu) with zo,o ammonia Slip". Results oflhis inilial RRI 

### lesling ul Siou}[plant wen: poor at cyclone**sloichiomelri~** 

### ratios c100c 10 

### 0.99 bcc.use inoonsislent, sporadic, and non-repealable NOx 

### emissions reduclions between zero and 15% were measured. Subsequent RRJ testing al Sioux Unil I 

### in March 2002 wiill SOFA al an average cyclone stoichiometric rntio around 0.95 showed NO" emissions reduction of29 pcrcenl (down 10 

### 0.27 lblmmBlu) beyond those achieved wiill 

### a modest amount ofcyc1one air-Slaging wilh SOFA (68% drop down 

### 10 0.38 IblmrnBlu from SOFA alone), for an 

### 80% overall dccrca'e from unconlrolled baseline; 

### RRI CFD model
MlnnkolO Power Cooperative, Inc. Bums & 

### MoDonndtNOx BACT Aualysls Sludy APPI.:NDIXAI Tedwical Fo"ibilily AS5essmenl Del.il, for NOx ('.<mtrol Technologic",
prediclions for Ihese conditions were NO, emIssions reduction of., 1% wllh Hill. and 37% withoUl FGR operalion. Tooled 

### NO>; emissions wilh RRJ+SOl'

### Ain 2002 wcre wilh a reagenl nOl'mali7"d**sloichiol1le~·,c** ralio (NSR) of] (II" Nil, per Ih NOx)".

Parnmelric te'ling al Sioux IiniI I in May 200S I'eduoed NO

### xemlssions belween IS-38% wilh 

### RRl, down 10 O.IS to 0.20 Ib/mmBlu. Rcagl"1l1 NSR bclwceo 

### 1.0 and 

### 4.0 and low ammOl1," slip levels kss Ihan 2 ppm from an e,lahli,bed ha,eline conditIon of0.20 to

## o.ns 1l)/rm"lJlu level achieved NO, emissions as low", 0.12 lbhnmBlU wilh deep oyclone ail'_Slaging and SOFA opc""lion rLring;m 80:20 PRBllilinoi, coal blend "I 480 MWg unil OUlpul".

n,e imem oflhe lUU process lor NOx reduction is lhal il must he ",ed in conjunction with air-"IUTV""**(Subsloi~hlOmelrie** slflged_air) cyclone eombustmn re,ulling from Ihc m,IflHallOn and operalion ofall OFA SySll"Tll, wilh ur wilhuul SNCR. The cyclone"' air/fuel sloichiomclry m\J'1 be carefully controlled to lll"inrnin fuel-rich ",,",Iilion, for lhc lUU process 10 be effecIive. The oombllslion g""" in lhe vIcinity 

### of lhe RRI urea mjeclion porls mus[ be essenllally devoid off,ee oxygen, in order 10 aVOId**oxidiziLl~** Ihe ni"of:en eootained in Ihe injeoted Ieagent, which will**iocrca~e** NOx 0",i,,,i01l.'. 1'0.-1 ignile-til'ed cyclone boilers, lhc b""o form of:;L1'""le<1 UVl.,-li", ;IIr (wilhuut ",loealeJ hgnilc drymg ,y,lcm wnl ports) is ll1compalibJe wilh 

### RlU. Rc"gcnl injc"Clion will be neor the eleva,ion oj" Ihc cxisling**h~ile** drying 'yslcm venl ports in (he lower Irolll "nd TC"r ,,,,,lIs ofa lib'lllie-fjred cydone hoiler located immedialely ahove the lOp nlW.' ofcyclone"_ n,e oxygen iolroduoed wilh Ihe lignile drying**~y'lellL·.,** vented moi.'llll"e_ladm airstreams will eausc Ihe ureu 10 he**o~idlZCd,** eroating 

### NOx emissions.

The advanced Imm ofSOFArcloc"les (hese**Ji~'Ilite** drying sy,lem veLlt ports from Ihe lower 10 the ",i,ldk 

## r umace, enhancing lhe desired in-fumace niIl'ogen oxides reduclion proco" Therdore, io order fur /Uti 10 be**l'~en** model aldy eHecuve in l'educJng NOx**emi."ion~** from a ji,,'IliLe-firt<] oydone hoiler, Ih,S**lechnolo~'Y** mu,l be**~umbined** wilh an ulj,,"neeu Imm of,cparalcd oVL"Tlirc "ir, whelhc.,- insl"lleu with Or Wilhoul,sNCR.


### A, menllunellin the [easiIJihly discu"ion of"pplying ",paraleu uvcrfil'c air 10 lignile-li",(\ cyclone boilers, lhe degree 10 which each "nd every individual cyclone fUn\ace can he suocessfully**opor~ted** wiill 

### Ie" lhun lheorelic"l (.,uh"loiohiomeIt'io) wmlmslion uil' direcily imp"clS pOlenlia] NOx ("orrMlion and further in-Ium"ec emi"i"n rc<1uclion. Bc-causc lhe heat conlenl oflignile Irom lhe Cenler mine**i~** not

Bnm, &. McDolJIlell AI·46APPENDlXAl Tcobnieal FeasibilityAs'CSSIIlOllI De",il. for NO:>: ConlrOlTechnologies NO:>: BAC]' Analysis Study

consistent from hour to hour, there can be subslantial deviations in air/fuel mtios for individual cyclones from the overall aVeI1lge.

In the case ofMRY Station boilen;, Minnkota. has simultaneously sompled lbe unprepared lignite reed to seveml cyclones' lignite drying syslcm, in order 1.0 determine the variability in the cornbuslible and asb components ofNorth Dakow lignite. Thi. invesLigatiOll found that fuel quality varialions <:an resull in individual samples' healing values to ha**~e** a maximum differential ofover 

### 12% oflhc lignile samples' average. 

### TABLE A1·1 - LigniLe Heating Values and Variations for Milton R. Young Station (Unit 2)
M.R. Yonng Slalion OJrrerenoes Betwc

....

"TI lndividual Individual Cyclone Lignite Samples CyclOlle**Li~nile** Samples HigherHeating Value•• }'erOCnl"ge of HHV Differential, PCTCentage of BlUllb Average l-111V BruIl" Avernge BUV Minimum HHV: 5,852 

### 88.9% Minimum: 4 

### 0.06% M"ximumH1-1V: 7,101 

### l-ffl%**IIJ"(',~** Maximum, 797 

### 12.1%

-- Averagc HHV: 6,584 

### 100% Average: 

# '" 2.51%

'Vben operating with air,slaged oonditions a,.,,;ociated Wilh separated overfire air, any individual cyclone wilh li!,'lIiLe heat inpul lower than**~ver~ge** can anow significanl amounlS ofoxygen 10 o"idi.", the urca reagent**~t** high temperatnres, thns increasingNOx emissions in lhat zone at lhal lime. Cyclones with lignile heat inputs higher than average would produce lower stoiohiometric airlfuel rntios and less NO" emissions. Less oomp1cte combUSTion in the deeply stuged cyclonc, may release imrnfficienl amounls or heul. Ihus rai"ing the risk ofsolidifying the fuel ash so lhat it accumulates within the cyclone barrel. This could resull in Dring auxiliary fuel oil or laking- the boiler oUl-of."ervioe to remove the plugg-age. Neilher oflhe.,e wndiliOlls is desi",ble because they resull in increased cmiosions, lower performance, and higher operating costs_

TheMRY StationUnit·i boiler's cyclone air/fuel mtios vary in TCal"!imebased on significant changes in combustible contenl on an individual cyclone by cyclone basis_ Adjnstment ofindividual cyclone wmbustion air inpuls to eompem.ate for the variability in indiVidual cyclone lignile heat inpul rates 

### for Unit 1's boiler would be necessary 10 maintain con,islc']]! substoiehiomclric operalion orevery cyclone during air-swged eombusliOll. This pluces**g-re~t** emphasis 011 achievinglighl wnlrol over Ihe air/fuel

Minnkom PowerCooperallvc, Inc. AI·47 I1ums & McDonnellNOx flACr Analy'i' SluJy APPENDIX Al Technical Ft·.sibilily A,,",ssmenl [)e",il, [m NOx Comrol Technologic,
rallo, on each cyclone dw-ing air-staged tOmbuslion opCI1lli"n in order forASOl'A 10 be succe",lul in producing sib'llificanl oJdilion.l NO" emissions reduction on lignlle-lired cyclone boilers_

There IS "0 equipmenl available for coaHi,ed boilers**lh~1** CO" measure 

### the fucl heal inpul al the prepared feed injeclion poml on s\Jch a variable fuel 10 allow Ibe delelminallon ofr"".<onahly**accur~lc** ulr/fucl r.lios on individual cyclone., m reallnnt. Wilhoul being "bie 10 me",ure the cyclone ,ir and heal inpuI, to allow for conlrol orair/Iud proporlions "m] emisSIons, the ,toichiometric rallo" 0(· individual cycloncs oa" nOl be ostnblishcd "cellrJlely to produce combuslion producl$ e.<senllally devoid of [rcc ""ygen. Thi.' requirement i, e'l'cei"Hy necessary when employing RRllO avoid merc"sing, r"lher limn reducing, NOx clmssions onlhe Millon 

### R. Young Stalinn Unit 

### 1 bOller.

Beoouse orIhe sJgnific.nl insurmountable problems discussed ahove which would incroasc 

### NO" emission rulc" 

### RRI lS con,i,k,,<1 Icehnieally infeasihle 

### for applicatioJ\ nn lho Unil 

### J oyclone buikr allho MIllon 

### R_ YuungSt,lion.



### A.1.4.1.3 

### SOFA with RRI and SNCR When RRI lS comhined wilh scpnralc<1 ovcr["e air a11d SNCll, il h"s demonstrate.:! very lIigh**NO~** emi"'om reduclioll al Conttliv's 

### RL. hngland Unil 

### 1 boiler during ,Illlrl-lerm le.'ling firing cuslom bitllminllu,**~o"l,** on the 

### ordn 0180% from an uncontrolled hoselme oTolmd 

### 1.2 lblmmBtu". In May 2005, lesling RJU+SNCR+SOI'A at Amercn's Sioux Unil I boiler finng a high J'Rn-blend coal demonstraled NOx emisswllS a" low"., 0. 12 lh/mmRlu. This was from an eslablished baseline cnndilion
or0.20 Ib/mmlllu level aohiovcd wilh 'kep cyclone "ir-staglng and SO!'A nperalion. Tho,e le'ling ",ulls**wh~."** firmg on**~O%;20%** ]'JW/JIliLlOi., enal hlend ol 

### 480 MWg ,mil oulpul wilh " rcagenl NSR 0 [ 

### 4 "nd ammonia ,lip limited lu less than 5 l'pmvd, .,howed an 'w",dI90% reduclion wilh no apparem adverse short-Ienn impacls ofdeeper alr-SLat",1 combuslion logelher with overfire air, 

### RRI and SNCR 

# , . - 

# " app lc"llOnS

.

Became ofthc "ib'llificanl insurmounlohle problcms rtgurding 

### RlU"S menlioncd above, 

### RRI wilh SNCR**~md** ASOFA i' considcred lechnieally infeasible for application on lho Ullil I eydoneboiler "I the Millnn 

### R. Yo"ng Sialion ,lue 10 Ihe variable heal comcnl orIhe 

### IigJ1ltc f\lel which allows Ihe ere"lion ofoxygen_ rich condilions in Ihe hoiler.

AI-A8APPENDIX Al Techni""l Fea,ibility A,s.essmont Details for NUx Control Teehnolog,e, NOx BAcrAnalysis Stndy



### A.1.4.2 SNCR and Reburn Various forms ofSNCR could potentially be installed downSlream ofseparaled overfin: uir and various lypes offuel rehum, to reduec 

### NOx emissions prior to a boiler's Ilue gas exil. SewroJ oflhesc examples
were already described').",lO,lI, 1m,". Conventional gas 

### (CGR) Ur coal rebum systems, by and large, have not been combined with forms ofSNCR. ahhough atlell.,t one vendor (GE Energy) has promoted u combination ofconventional gas rehum with SNCR and ovcrlire air systems as "advanced" gas rebum. Only one example ofpermuncnt instalJu(ion ofSNCR with conventional gas rcbum (und overruc uir) on u lilngentially-firedb"iler was found in availuble teehnicalliterature'O and vendor expcrience lis15". The vcndor (GE E"ergy) that provided the advanced gas rebum system at 120 MW NRG Somerset Station claimed NOx cmissions were reduced by44% from a baseline of0.45 down to 0.25 lh/mmBlu with overfire air alone; an additional**redue~on** of20% resulling from convenlionaJ gasreburn Wilh overfire air, down lo 0.20 Jh/nnnBtu; und further decrease of45% down to 0.1 I Jh/mmBlu using gas rcbum with SNCR wilh an unstated amount ofarmnonia "lip, for an uverall reduclion of75% from uncontrolled baseJine".

No examples ofac(ual demomlralion Or permanent instalJation ofSNCR with cunVC"ntional gas Orcoal rcbum (and overlire air) on**cyclone-fir~'XI** boilers were found in a search ofpublished and proprielmy tcchnioalliteratnre_ The lack ofexperience with these combinations on a cyclone-fired boiler, especially for lignite-firing, m"k<.:s thc application forMRY Station'" boilers infcasible_



### FI.GRTM bas been imlalJed wilh SNCR for NO

### x emission reduction on seVC"ml pulverized coal boiJers,"" discussed in lhe following suhsection_ A potl"TItial advamage ofFLGRTM over conventional coal or gas rebum techniqucs is that 'he former is genernlly compatible with, but docs not require, the inSlalla'ion and O[lC",tion ofSOFA.

Rich Reagent Injcction would appear to be Jess capable ofbeing combined wilh fuel rebum, especially conventional fueJ rebum ahcmatives wilh high amounts ofrebum fucl injcction. This is due to the expected need 10 idJe (e_g. not fire) up to two oflhe seven cyclones when operating Ihe rcbum syslem al full boiler lood. 

### In this case, tite cooling air inlroduced into the idJe cyclones, and any convcying air injected with pulverin:d rebum coaJ (or ifnalu",l gas is injecled withrecirculate<! nuc gus), arc expccted to**count~,.ael** Ihe fuel·rich condilions ofthe air-and fuel-slaged cyelones ope-r",ing substoichiomelricaJJy_ This will cause a portion ofthe "mine reagenlto be oxidized in the lower furnace. cr""lingNO

### x emissions instead ofconverting them to nitrogen and wateL No example ofactnal demonstration or permanent inslOIJation orRRI with rebum (and ovcrIirc air) on cyclone-fired boilers was found in
Minnkola Power CooperaIIVe, Inc. AH9 Durns & McDonnell**NO~** BACT Analysis Shldy

_.-. APPENDlXAI Technic"1 i'ea,il"lilyAsse"mml Delail< lOr**NO~** CODlTOI Technologic'

UVUlInhle**l~'{;hnieJllilCTatu'** e Or vendor cxperienee l'sls. This combinatioo is consLdernl infea'ihle al Ihe present time_
Hyd, ocarbon-enhanced SNL1l 

### (c-r

.. NOxSlar Tht ) maypOlCntially be comi>im;d with

### nil Iype' and fomll of reburn prcviou,ly discussed, since lhc lucalion ofIhc enh"ntoed ammon", i'ticelion nozzles ""ill he above (beyond) the elevalion in the middle furnaec where "ny rel1Um fuel Hhould be reaelcd. No**c~amplc** of aclu" I demonslrali"" orpel'manent in,'allallon ofHE-SNCR wilh rcburn (and overllre air) un any coul- !ired ulilily**boilcr~,** espee",lly cyclone-fIred umts,**wa~** [ound in available**le<:hnLealliler~ture** or vendor <:xperiencc lisls. Thc advanl"gc lhat IIE-SNCR presenls is Ihepolenli"l for**~"eater_lhan_SNCIl_lcvcl"** of**NO~** ,educlion wilhu<JI ,igmficant amounts ofgnseouo hyd, oearbon hei"g required_ I3ctnlL';e ofa Jack 0 [. c"pcTience wilh 

### IIE SNCR applicd 

### 10 cyclonc builers, and "One wilh ,ignilicanl amnunls offucl reburn, Ihis combination ha, not bc"n Investigalcd LUI1her, und wa, nOl included in the control and cO'I_ drectivcnc.<s**"nuly~is** for 

### NOx controls.


### A.1.4.2.1 Amine-Enhanced FLGRT'" (AEFLGRT"') or FLGRTM 

### + SNCR Fuel-leall I':"S reburn has been ctlmbined wilh SNCll as a hybnd r",m of"mine**reJgenllechnolob';~o** On at kasl !"Lve pulveL'Lzed eoal-G, ed uhhly**pnwerphmt~** retrofil inslaliallOnS wiLlun the llnLted**SI~lcs.** Tlli' combinalion oflechnologic, allows Ihe bOllcr lo bc operale<1 WiIh FLGK'" alone, l'LGRn-, and SNCR**~illlullanct>usly,** or SNCR only (wilhoul SOFA) for the' specific level ofcontrol deslr,",l nr reqllircd.

No c"amples ofactual demonstralion Of I,ermancnl in,lallalion ofFLGRTM 

### + SNCR (with or Wllhoul ovcrfire air) applied 10 a cyclone-fired bOiler**W~TC** [Gund in avaibbk**l~chnical[il~Talure** or vrnd'"**cxperien~"** lisl1;, n\e vendor (Fuel Tech) Ih'" provlde,1 the AEFUiR'Msy,lcm al Mercer Slalion olaimed 

### NOxemi'Slons \Verc reduced by 60% (from a ha,elinc of 1.4 down lo 0.56Iblmmlllu) wilh 5 ppm ammoni" slip-",'Ihoul ovemrc alL A leehmc,,1 paperprovides mOTe delail,". Anolher lechnical**pap~T** .,Ialed lhat I'LGR'" alone only ,educed 

### NO., ennSSlOn, "pproximately 

### 27% ITom tho 

### 1.4 Ib/mmBm ba,cline, down 10 

### I.OJ IhlmmHlu".

An 

### AEFLGR'"**,y~lem** (wilh Ofwithoul 

### SOFA or ASOFA) muy he**pol"nli~lly** apphcd 10 a <:yclone.jJ,ed boilor. Thc Il1gh c"pilal and opcnlling cosls**as~noialed** wilh applying fuel lean 

### P-' rebum i' expecled to makc Ihis cconomically unmtr"ctIV(:, ,,,d the cxiSling ligniIe pre-Jrying venl purlS Wlillikdy limillhe NO" ,.nission ,-educlion polenli,l ofIbe FLGRu, eun,poncnl iL in,lallcd without ihc udvanced form 0[· ;>;.

Dum' & McDonnell AI·50 Minnk<>la power Coopora'io", Ine.APPENDJXAI Technical Fc"ibilityA",,",mcnl Dd.il, for NOx COD[[ol Technologies NOxDACT,

SOFA_ The lock ofexperience wilh this combination on any cyclone-fired boiler, especially fOL firing, makes this comhination infeasible for MRY Station Unit 1 boiler_

MiDnkO[a**Po_rCo~peTalive,** Inc, AI-51 Bums &**McD~nncll**NOx (lACrAnaly>i. Sluuy APPENDlXAl Teehnic,l Fe,,->ibility 1I',",ssmenl Details for NOx Conrrol Technologies

----------_.- - Technlcallilerature References:
"B&W's Advances on Cyclones NO" Conlrol Vi" 

### Flid and Air Slaging Technologies", by I'arzan, B

.. Maringo, G.• lohnwLl, D. W., 3ml Wong, D,K, (Babcock & Wileo". Co.), Ileard, CT. (Ea5tman Ko,bk Company). ,mu Brewsler. S.E. (Tenne.«ee Valley AUlhoriIy), pn"c'IIleu "t lhe El'RI-DOElOPA Combined Ulilily Air P"llutanl Conlrol Symposium, Allanta. GA, AuguSl 16-20, 1999. Available al ll&W's internet web,ile, htlp:!!www.babcock.com/pt<!!/lllpdffBR-1683.pdf l 'The l':lale oflhe Arl in Cyclone RoMr NO" Rl'dul'lion", by O'Connor. D,ve, llime,. Rick, and**Fa~ehi"no.** Tony (Electric Power Re,earch InSIilute), pre<enled allhe EPRJ-DOE-EPA Combined Ulility Air Pollulant Conlrol Symp",ium. Allanl", GA, Augu,l 16-20, 1999.
3 EPA Dockcl OAR-2002·0076·0446 Tcclmi"al SUPPOlt Documenl lor BART NOx l.imil" 

### tnt Eledric GL"Tln"lmg Uml" E"cel Spreadsheel 6flS/200S, pO"lCd 0" lheir wcb,ile: from EDUCK.ET al hllp:11dockcLcpa.go

### vI**~<l]"** pullldolEDKSlafill"mDel"11View'lob JecIId=O 0007d4ROR4S(,2b; tl,j, is n"oeiutcd wjlh EPA Acid Rain l'rogram Clean Ail' MarkelS Divi,ion, Technic"l Support DocumentMelhodology I'or**D~velorjng** FlARTNO, PresumptIVe Limits. June 15, 2005, OAR"2002-0076·044.1, 4 Moboledll':A experie"oe li.'1 and techn"logy ""planalions, available fmm Iheir wC]'SilC nl Illlr;

### /1www.mobolcclISJ.con16.Ko 

### j**ecl~** in,I"Iiali011>.hl,nan,] hI

tp:11www.mobolC<::••Sa.com/lce000logy

### lrofa.hlm
5 "NOx RC(Juelion From A 44-MW Wall-Fired Iloller Ulillzing O"ygen Enhanccd Combuslion", Prn"air. by Dool. I.awrence E. III,**~nd** Flru,!icy, llJITon, prescnl"d al Tl1e MEGA Sympo.liom, Was],ioglun D.C., May 20, 2003.
6**"COmhLJ~lion T~mpcring**  '" Conjunclion Wilh SNCR**Reduc~,** NO. Emi",ions Nc"r1y 6U% on a Natural Gas Fired Cyclone Boiler", pO,IL-J "I th"irmlemcl websile: h1!l"1/www.rimcom.com1pdflMi<13**\~A.c.:.** pdf
7 "Clean Co,1 Tcchnology: Rcbum 1'edmologie, for the Control ofNilrogeo Oxidcs Emissions from Coal-Fire,1 Boilers. Topi"a! Report Number 14, May 1999", U.S. llq",rtmenl ofEnergy (DOE). Posled allhe i"lernel wcll.,iIC: h1111

### :11www.J9..- ••**].energy.gov/pr~)~rarTl** .•/flO

...·r:.y.•I<:"../ mlbIi""11onsiClean Cool 1'01'i cal RcporL ",I 0I,i caI1.4.·p4f 8 "Clean Coal Technology Program,,: Projccl f"el Sheels 2UUJ. Include" Clean Coal TecOOol"gy Dcmonslmlion**I'rogr~m.** as ofMay 2003, OClober 2003", U.S. DqJartmenl ofEnelgy (DOr.). Availahle 10 Ihc public from lh" N"IJOnall!nel'f'Y TedlL\olngy l.aboralory's Clean Coal Teclmology Comp"ndiom: hItR'!i..W\\',,'.1"".1"govIllI'ojcc**I~f** ccleiinde,.hI mi.
9 "R"buming Projecl, III (he DepartmefiIofEnLTgy'o Clean Coal TechnoloGY Dcmomlmlion Prq,""'"'" by Mann. AI and Roppel, Tom**(Pars"n~** Corpomlion), and Sarku". Tom (Nnlionnl encrgy Tcdmieal Lahornlory),**prc:;enl"~l** a! lhe 20114 DOE-NETL Conle,-eIlcc On Rcbummg for NO" Contlo1. Morganlown. WV. May 18, 2004. A rebum-related document (an**Ol,~al"'{l** vC"T'10n of" poster from L1w**M~y** 18 Con[LTC"TIC") i" lilled ·'l':cOl'ccnn:1 On Rcb"miog 611/2004" by AI Mann and T0'"**Rupp~l,** Parsons COTpOrnliUII, uvuil"ble on-line at:**h!lp:II~'L~etl.doe.gov/pul,licnli"nslpro"eCJ!ing:,.I04!NO~!j1os1e"'lRcbuming%20Scm:ecar.d.pdf** 

## ,'i

,

## .,

BlUrb &: McDonncll Al-JL Mint1kOIO Power**COOr~rdli\'c.** Inc.APPENDIX Al Technical Feasibility Ass",",mcntDelails for NOx Comrol Tcchrmlogics NOx BACfAnalysis Stntly



### to "Experience With Rebum for NOx Emissions Control", Engelhardt, Don, Payne, Roy, Moyeda, David, Folsom, Blair, GE Energy, presented at the 

### 2004 DOE-NETL Conference 00 Rebuming; for NOx Control, Morgantown, WV, May 18, 2004.
11 "B&W's Reburning; Experience", by Farzan, H., Maringo, G., Yagiela, A., Kokkinos, A. (Babcock & Wilcox, Co.), presented al the 20M DOE-NETL Conference On Rcbuming for NOx Control, Morgantown, WV, May 18, 2004.
12 "B&W Cyclone Rebum Leads to NOx Reduclion, Wisconsin Power & Light Co. Nelson Dewey Unit No.2" (cusc history from B&W's internel wcbsite hup:ffwww.babcock.comlpgglps/casehistories.html. daled 

### 1997).
13 "ReburnTechnology,Applicalion Guidelines", Moyeda, David, Hartsock, Don, and Payne, Roy, GE Energy, prcst'fltcd althe 2004 DOE-NEI"L Conference on Rebuming for NOx**Conlro~** Morgalilown, WV,MayI8,2004.
14 GE·EER experience h"l, SC"plembt'T 29, 2005. For wull-fired coal rebum, and gas rebum wilh SNCR, see**"PowcTpl~nl** mosaics: paving lhe way 10 0.11 1\lIMMBtu wilhout SCR", by Folsom, BlairGE Energy, published in the March2004 issue orModernPower SystenR 15 "Predichons offLGR**~l** CommonweaIlh Edison's JolietUnit 6" by NGB Technologies, posledon their websiIe: htlp :/Iwww _ngglech.comlsubwge"fprojIjoliel results.hImI 16**~FLGR** Aclvisor 

### s": A Boiler EvnluationTool for FLGR-Buscd 

### NOx Reduelion Systemsby NGB Teohnolog;es Inc., poslt,,1 On lheir websile: http;/fwww.ngblech.comlsubpoges/projmm adv;sor.pAr.
17 "CfO Evaluation ufFucl Lean Gas Reburn (fLGRTht) and SelectiveNon-Cutalytic Reduction in Owensboro Municipal**U~hlies'** Elmer Smith 5lalion", by Wang, David 

### H_, Cremer, More 

### A., Adams, Bradley lL (Reaclion Engineering International); FrizzeIJ, K.D. (Owensboro Municipal Ulilities); Dusatko, G.c. (Sargent & Lundy), presented at th. 2001 US EPAfDOE MEGA Symposium on SCR and SNCIl.s, Chicugo,lL, August 20-23, 2001. 18 Fuel Tech experienoe list daled 1/28/2005. 19 SNCR "While Paper", Inslitute ofClean AirCompanies, Inc. (ICAC), SNCR Commillcc, May 2000, Fuel Tech website http://www.fucltcchnv.comfpllrrrPP-534.po;l.f.
20 fUM experience list, September

### 3, 20{)4_
21**"NO~SLarTM** Plant Demonslrdlion, October2003", by Morris, K.W. and Hesselrnan, 

### G., MiL'illi Babcock (US), presented at the 2003 

### UK DOE Conference on SCRand SNCR lor NOx Control, Pittsbmgh, PA, October 29-30, 2003.
22 "lnstallalion ofNOxStarTM Systorn al TVA Colbcn", by Morris, Keith W., Mitsui Babcock (US), presented at the Coal-Gen 2004 Conrerence, July 28-30. 2004, Overland Park, 

### KS_ 2J "Improved Rich Reagent Injcclion (RRJ) Perrormuncefor NOx Control In Cool Fired Utility Boik-n;" by Cremer, Mare A.**~ml** Wang, IIuafeng D. (Reaclion Engineering Intenlalional), Boll, David 

### E- (AmcrcnUE), Schitldler, Edmund 

### (RJM Corporation), and Vasque7, Edmundo RMT,lnc. (AlIiant

MinnkU\d Powe, Coopernli,'c, ITIc. AI_5) Burns & McDotlnellNOx IJACr Analysis SLudy APPENDlXAl Technical FeasibililY Ass<>smo;nl Dc!.>il' fo' NO" CunlTOJ Teclmolngies
Energy Cnrp.), presenled al 2003 U.S. DOE Conference on liCit and liNCR ror NOx Conlrol, Pillsburgh, I'A. Oclober 29-30, 2003.
24**"D~,ign** and Demnnstralion ofItich Rengenl Injections (MI)**P~Tform"nce** For 

### NO" Redudion al Conneeliv's 

### BoL. Engl"nd SI"li,}O" by Cremer, Marc A. an,l A(l.ms, Bradley R. ("""clion EngineeriLlg Inlernalio,,"l); 

### 0 'Co""or, 

### D"viu 

### C. (Eleclric I'ower Itesearch Institule); Bhnmidipall, Venbla (Conectiv B.L Engbnd Sialion), and Broderick, 

### R. Gifford (RJM Corporalion), pl'e.,e"led al Ihe 2001 US EPNDOEJEPR! MEGA Sympu,ium on SCR and SNCRs, Chicago, 

### [I., Aug"sl 20-23, 200 I. (availahle Jeorn REI', internel weh,ile hllp:llwww.rcaclion-cng.eom/Jonwl

..**~d** ....ITimol!...pdD
25 "Dc'111onslralion ofRich Reagent Injeclion lor NOx O.,"lrol In AmcrenUE's Sioux Unit I" by Cremer, Marc II. ,mu Au"m" Bradlcy Il. (Reaelion Engineering IJ\lernalio"nl), Bull, David E. (AmcrcnUE), and O'Collnor, Davld C. (Eleclric Power Re'earch**Ins~llIle),** presenled allhe US DOE Conference un SClUSNCIl for NO" Control. Pitt,burgh, PA, M"y 15-16, 2002. 26 "Evalualinn of("o,l Effecll

__e Non-SCIl Options for NO" Contml in PRE fired Cyclone BOllers" by**Crem~r,** Marc A.• Wang, David 

### 1·1. and Adnms, Brndley 

### R. (lleacllon Engineering InlenlOllOnal); Boll, D.vid 

### 10. und**Sluckm~ycr,** Kcnnelh B. (AlllCrenUE), pl'e.,ented JI Ihe We'lern Fuels Symposium, 19'" Inlernational Conference On Lignilc, Brown, anu Subbilulllinou, Coalo (f(lrmc"fly Low-Rank 

### f 

### "eI,), Oolober 

### 12-14, 2004, Billin.:." MT
27 "NOx Emi",iollS Below 0.15 lb/Mblu Achieved in a Cyclone_fired ROller U,ing In-Furnace Cunlwl", by C. emer. M., Adams, Il., nm] Chiuuo, A., (Rcaclion Engineering !merna'io""I);**Gie."'~nn,** 

# c., Sluckmeyer. K., and Boyle, J. (AmerenIlE), prc&enlcd al Inc Puwergen Inlernalin".1 2005 conference. Deccmber 6·8, 2005, Lus Vega" Nevada.
28 "Ash and Mel'cu,y**Reha~ior** in SCR Cal"ly'ls When Firing Subbllltlllinou, nnd I,il",lc CO<1ls'", Energy & Environmc"fllli Research Center (cERC) 

### ofthe Uni"e"ily ofNorlh Dakola", Ilen.'on, Sleven A., taumh, Ja,on D., Crode"f, Ch"rknc It., and Pavlish, John II. subm,uttJ fur publio"lion by fuel Procc%ing Technology magazine, 2004. An ediled vel'sJOn oflhis paper was published us: "SCR C"laly,t Porrorm.ncc in Flnc Go,".**Dcr've~** from SubbiluminDu,**au~ l.i~n[le**  Co. I'" by Fuel Prnce.'Sing TeciUlology, VQlollue 36, 1>"ue 5, 25 FcbrWlfJ' 2005. P.ge.< 577·(013 Sluvcn A. Bc",,'o", Joso", D, !.31ll"b,**C1",rleJl~** R.**CJlJck~r** amiJohn H. PavlL,h. 29 "In-Silu Mim SCR Reoelor" study. available (for pllrcha,e from) Electric Power Researoh lnslilute Inc.', (EPRI'0) inlcrncl wcbsilc "I hlip;

### IIwww.epn.com.l• .!.\v.lell

...**~!.B.I..1i** ",tieid- 2 

### 7J05&m"rkctoid 27_U_61 

### 9&tame

### Inirl 270677&valu**c~** O'iTOn.O )0 ·'Recenl Expcric"flCC Wilh Hilachi Plate Type SCR Calaly.<l", Morilfl, Isnto, Og1Lsahara, Tom Fr"nkJin, Ilowa'd N., Bnbooek-Hilnchi H.K. and Hilachi America lechnical p"pn, prc,;ented 10 The Inslilule ofClean Air CompanJes 

### FOnJl11 '02, february 

### 12-13, 2002, Washinglnn, D.C.
J I '·l'erformanee

## orScleClive Cllnlylic Redllclion On Coai-Fil'ed Sleam Generaling Unils" I1.S. EPA Office oflIir aod ltadialion ACld Rain Program Final Report, (620<1-J), June 25,**1~97.** ]2 ·'Rolating Opposed firc Air (ROFA) and SNCR'", by Shilling. Mark and ToIl"maker, Gary (Carolina Puw", & Lighl Co.), rre.<enled allhc 2002 DOE-NETL Conference on Unburned Curbon on Ulility I'lya,h, May 14, 2002" I'iltsbmgh, I'A.

Du'os&McDUHndl r.-tirrnkula Po",e, CoopeI3LJ\'e, Illc.APPENDIX Al Technical Feasibility /I,,=mcm Details for NOxControl TechllolQgio, NOx BACrAnalysi, Smdy

33 "Injection ofUrea lhrough lhe Rotamix System [0 Oblllin Improved NOx Reduclion", by Ra]<lon, John und Haddad, E<lwin (Mobolcc USA, Inc.), presel\ted allhe 

### 2003 U.S. DOE Conference on SCR and SNCR forNOx Conlrol, Piltsburgh, PA, OClOher 

### 29-30, 2003.
34 "SCR Levels ofNOx Reduction wilh ROFA ami ROlllmix (SNCR) at Dynegy's Vermillion Power SlaLion", by Coombs,**Kristoph~T** A. 

### Sr. (Dyncgy Midwest**G~"T1cration).** and Crilky, Juy S., Shilling, Mark and Haddad, Edwin (J\1oholec USA, Inc.). presenlc<! allhe 201M St"ck Emissions Symposium. ClearwaterBeach, FL, July 28-30, 2004. 35 "First Commercial InSlnllation ofAmine Eummccd**"11~1** Lean Gas Reburn On Uuils I and 2 al Public Service Electric & Gas Merccr SLation", by Gomez, Andrew F. (public Service Electric & Gus Company (PSE&G) McrccrGeneraling**SIa~on),** Dainoff,**AlexJn"~"[** S. and O'Leary, John II. (Fuel Tech.lnc.), and Schrecengosl, Robert (Energy Systems Associ"tcs), presented at lhe 2000 DOENETI. Conference on SCR and SNCR for NOx Control, Pittsburgh, PA, May 

### 17-18, 2000.



## * 

## * * 

## * *

Minnkola PowcrCooper;Hive, Inc. At-55 Bum' & MoDunnellAPPENDIXA2 u.s. NOx Control Relrofil ProjccLs


### A.2.1
- U.S. Cyclone NOx Reduction Projects Summary NOx BACTAnalysis Study

1962 vintage easlern biluminOuS coal 

### SELECTIVENON-CATALYTICREDUCTIONtRICHREAGENTINJECTION Cyclone-Fired Boilers Conectiv (rormerly Atlamic Eleotric) ilL England Unit 1 Cmslicd Coul, smgle-wull cyclone-fire<J 138 MW B&W boiler aqueous urea SNCR, 1995 slartup BOller has only 3 oyclone burners, armnged "lover 2" slyle. RJM implemenled commercial Fuel Tech uroa-b""cd SNCR system inslallalion in 1995 after short-lerm (3-monlh demopslralion lcst)**i~** 1993-1994_ 31 % NOx reduclion claimed, from 1.311bfmmBtu NOx baselinelll for SNCR only; RJM claimed 35% reduction rrom I.] Ilb/mmBlu down to 0_85 IblmrnBtu (wilholll overfire air) wilh ureu-lo-NOx NSR = 0.85 (RJM expcriencc list). Added cighl temporary

# roo pons (three nozzles on each lower sidcwall, and two nozzles 

# on !he upper rearwall, and perrormed one monlh demonslmtion paramelric tesling ofo"erlire air only (wilhout SNCR Or RRl), at 120 MW nominal \)(Iiler load and cyclone S.R. e= 0_90 in 1999. 

### REI claimed 55% 

### NOx reduclion from a 1.2 lblmmBtu unconlrolk<l NOx baseline to 0.55 Ib/mmBlu with OFA only, with stack CO emissions below 50 ppm_ For Rich Reagent Injeclion; 

### REI claimed 25-30% NOx reduolion for 

### RRI down 10 0.381b/mmBtu from controlle<l**buseli~e** 

### wI OFA alone of0.55lbfmmBluNOx and a 

### RRI urealrl-NOx NSR = 2; also showed RRI+SNCR w/ OFA reduccd NOx 55% to 0251bfmmBtu (J4% beyond RJU 

### wIOFA), for an overa1179% NO" rc<luct;on with a SNCR urea-lo-NOx NSR = 1. Measurcd less than 

### 1ppm ammonia slip during RRIlesting, 

### < 5 ppm slip for 

### RRI + SNCR. No significant increase in CO emissions during RRI teslin!f). Source: (1) ICAC While Paper; RJl\II experience lisl; t')

### REI 200 j Technical Paper. Conecl;v (fonnerlyAllaulic Electric) 

### BL England Unit 2 Crushcd Coal, cydone-fired, single-wall-fired 1964 vintage 160 MW IJ&W boiler SNCR, 1996 slartupeaslem bituminous co.1 

### RJM implemenled commercial Fucl Tech urea_based SNCR syslem in 1996, claimed 36% n:duclion from 1.36 Ib/nunBlu down lO 0.85 lblmrnBlu, urea-lo-NOx NSR = 0_85 (without owdire air)ll). An OFA**sy~tcm** was added iu 1998, rc"Sulling in NOx emissions of0.33IblmmBtu, for an**oV~'Tall** NOx reduction of76%. Source: 

### IUM experience lis!. (Also lisled in (1)ICAC While Paper). Amcrc"]]UE (formerly Union Electric Co.) Sioux Unit I Crushed Coal, opposed-wall cyclune-lired 1969 vinlage 500 MW B&Wboiler Rich Rc"gem Injeclion demonstralion 1<Sling in 2001 Boiler has 10 cyclone burners, lIITanged "2 over 3" style, on opposite w.ns, and fires a blend of85% 10 50% weslern sLibbiluminous 

### (Pill) cool, with 111;nois biluminous coal, pelroleum coke, and lire-derived fuel. losl.llcd lwcntytemporary 

### IUUports (six nozzles on each lower sidewall, and rour nozzles on each front and rear wall), and performed one month demonstration parametric lCSllng ofovernrc air only and initial !csling with RRI in Augus12001, followcd by additionaltestillg in March 2002, and lhe second quaner of 2004. Added 

### 8 RRI ports (1 in each sidewall, 

### 4 in each front and rCar wall) and 14 SNCRpOrlS (5 on upper front wull, 9 on upper rearwall) lo lhe furnacc in curly 2005, followed by 

### three weeks Ofp;lmmclric tesling and J days ofconlinuous tesling ofRRI wilh SNCR and doeper-slaged OFA_ Tested in Augusl200 1 at lower furnace SR approx.=l.O, 0.551blmmBtu 

### wIOFA only, only 15% NO" reduclion wi 

### RJU, zero ammoni•.slip.

Minnkol. Power Cooperative, Ino. Dums & McDonnell**NO~** BAel'Anolysi_, Siudy APPENDIX A2 U_S. NOx Conllol Relrofil Projccl!.**T~.,t~d** i" March 2002**allow~r** lumace SR approX-"--D_95, from 0.381b/mmBtu haseline wi OFA only, achieved 29% NOx reductlOn wi RRl down to O.27lbfmmlllu, NSR=3, 7..,ro ammonia slipt')oo (ns,llmc ble-nd llfPRB and 11linois bilominou" conI w/lirc-dcrivcd fuel and pelrole,,,n "okefl_ OjJualion in 110,'**s~coll(l <1llnT1~r**  2004**show~d** aclual slackNOx averagcd "mum] of0.30 1l>lmJTIBlu wilh OFA only and lower li,rnace 

### at" cyclone SR arnund O_H8 Imming n 85% PRIl, 15% JIlinois 116 bilummous cool blemJ, prc",mably at**~~O** MW_ This IS 0 75% NOx reduclion from a 1.191b/mmlliu pre- "onlrol b"""line, 

### REl uoing Cf'O modeling predicled NO" ,lawn to 0, 181blmmB\\1 wilh RRl+OFA, ond helow 0_15 wilb ltR11 "NCR under similar deep cyclnne oir-.<I"ging (1.19 10 O_2X Ib/mmlltu is 76% reducllon, 0_1 vs 0.28 j, on mJd,llOnaJ 36% reduclion w/IUU, ond 0_14 vs**0_2~** is a 50% rcduclion wI RRI+SNCR, for On overall rcdoelion of88%tl
,**Test~d** in May 2005 al 4g0 MWg With. lower fumace Sll approx_ = 0_S5-IUS, 76-83% redllclion Ii-om 1.2 IblmmBlu b"stllne down 10

## w, low

## w, 0.20 lblmmBIU wI SOFA only firing 80% PRB, 20% IIllnoi" 116 hitummous coal blend; additionol 15-39% NUx reduction wI RRI, 10 as low as 0_15 IblmmBlu from 0_20_ 0,281blmmBI\I bllsdinc 

### wi SOFA only al urea NSR v,meu belween 1 ond 4, wilh one ppm llmmonia slip; achJeved addilional NOx reducllOn 

### wi RRI ! SNCR down 10 0_12 IhlrnmDtu,**NSR=~,** ammouia sliplO ppm Or less_ RR]**~SNCR** wi SOFA NOx redudion percenllige vllritd from 15% to 50% below SOFAonly levels, wilh NSRs belween I and 4.5_ SNCR alone had lJ% (NSR=I) 10 32% (NSR=I) NOx re<luelion Wilh ommol\ia slip around 1-2**Pl'm~_** Source: "I REI 2002 on<120031'cchnicoII'0p"n;; (') REI 2004 Techmcol p"per;* REI 2005 Technical poper. 

### REBlIRN- GAS, CONVENTIONAL Cvclnne-Fircd Boilers COTlSlcll" li"n Fnergy (Io,merly Ball,"'ore 

### Gao & Eh:l.-ie) CJ'

_Cr"ne Stalion, Unil, I & 2 (MD) Crushed Cool, eyclone-Jired, eoslem blluminous coal 2,200 MW B&Whoilers (foureyclones ciwh) 1961, 1963 vinillge GE-EER ConvcntlOnal Gas ReblPm, 1999 slmlup A<1,lt<l gas .,upply piping, mete, ing,**hal\g~,",** suppnrL,; ['chum injc"CloT> and ""ollng airduel,,-'ork, OFA duclwork, injeclion nozzles ond woll pOlis, field (assume ea.,te, n hituminous coal) GE-EER claimed Gos Rehum wlth Of'A lowered**NO~** bclw<;C"Tl 60% a",165% from bll,dines of1.50 Iblmmlliu 10 belween O.GO and 0,52 lblmmDlu, 01 fulllood wllb rehurn opemlion. No claims ofperceot rcbum fuel or percenl 

## orA included in C,E-FER', experience Ji&l. Anolhcr Icchnic" 1paper showed Ihi, insl"ll"tion ofCGR operaled with 25 p<-TCcnl rcbum fud'i. SOllrce: Sept. 2005 GE.EFR experience**I,~I;** ('IDOE.NETL ScorccanJ un Rebumillg 6!Jn004 (from**200~** Rebum Conferen"e). City Waler, Li£hl & Powcr I_.h.,ide llnil 7 Crushed Crull, fronl-wall cydone·Jirc-o, midwe.'lero hituminous coal 300,000 Ib/h.r s(eam B&W hoiler(approx_ 33 MWe equivalent, two cyclones) 1961 vinlage Springfield, It DOE (1eon Coal demOnSlmlion projeci**(in~luded** sorbenl injeelion) GE-EER eonvenlionol go, rcbllm 

### wi OFA 1992 slartul' (CC,R not eurrenlly opemling) Vcndor claimed 10 lowerNOx hy 66% [rom 0_95 Ib/rnmlllu ba,eline lu 0_32lh/mmBtll, A GTi·EER 2004 1eehnieal paper showed 25% rebum [uel yJelded mmimum NOx emissiom('l_ A DOE NE1"L lechnical poper showedlhis demonstration ofCC,R from 5/93-]0/94 (assume wilh OFA) wilh 23 pereenl rehum fuel reduced NOx 60% from 0_97 10 0.J91blmmHtu 1'1_ Source: Scpl. 2005 GE-EER exp"riencc lisl; ('IGE_HER 2004 Technical ]YJp"r;(SIDOE-NEfL 2004 Rebllm Conference Techrlie.l paper_ E",lm"n Kodak Company Kodak Park Boile" I & 42 Crushed Cool. fronl-wall cyclone-fired, 1%4 & 1966 vinlage
Bum, & M"Do"nell A2-2 Minnkola**Pow~r** Coupcmlive. Inc_APPENDIX A2 U.S. NO>: ConlraJ ReuantPrnjccls NOx BACT' Analysis Srudy

400,000 lblhr steam B&W boilers (approx. 50 MWe cquiWllenl, Iwo 8_fldia. cyclones) Roeh"Ster, NY eastern bituminous coal H&W convc'1Itional gas reburn wI OFA December 1998, July 1998 startups (slill opcruling) Commercial installation ofCGR, wilh (I) gus bumeradded 10 each si<!cwall 

### + (2) largc and (2) small OFA porls added Lo fronl wall above cyclones, ulilizing higher reburn gas pressurc (vs. Boiler#43) requires no flue gas recirculation; {Very small Hlrnace wIcyclone SR not <1.01· B&W claimed ",hum wilh OFA lowered NOx hy 50% from 1.20 IhlmmBtu baseline 10 0.6Ib/mmHLu. B&W graph shows 10-12% peroenl rebum fuel 10 achieve 0.6Ib/mm13tu and 23-24% rebum gas inpul 10 reach 0.33 Ib/mmBlu NOx (7J% reduoI;on)(1). Anolhcr ledmioal pap-er showedNOx lowered by 52% from 1.25 Ib/mmBtu baseline to 0.60 lhlmmBtu with 18 percent relmrn fudsl

. Sourcc; [7)n&W Technical 

### Pap",,; 1')nOE-NETL ScorecanJ on Rcbuming 61112004 (from 2004 Rehum Conference). 

### REBURN

- GAS, CONVENTIONAL Cyclon<>-Fircd Boilc,", cOnljnuell Eastman Kodak Company Kodak Park Boiler 43 Crmhed Coal, front-wall cyclonc_fJred 1968 vintage 600,000 Ibihr steam B&W boil"" (approx. 

### 60 MWe equivalent, two cycloncs) Rochesler, 

### NY eastern bituminous coal B&W conventional gas rcburn 1995 st:lrtup {sLill operating) -Commercial**insloll~lion** ofeGR, with flue gas recirculation (FGR) for injection m"SS momentum wI (I) FtiR fan; (1) gas burner addc-d to ench sidewall 

### + (2) OFA ports added liontwall aixlve cyclonc>. [Very**~mall** fnmaoe/low residence time wIcyclone 

### Sft not <1.01 13&\'11 clu,med reburn with OFA & FGR lowered NOx by 50% from 1.20 Ib/mmBtu baseline 10 0.6 Ih/mmIltu. B&W graph .hows Ig% percent rcbum fuel to achieve 0.6 IbfmmBtu and 29% reburn gas input to rC'deh 0.36 IbfmmBtu NOx (70% redoetion)m. "Another technionl puper showedNO>< lowered by 56% from 1.35lblmmll1n baseline to 0.60 Ib/mmBtu Jiith 18 perc""t rehum fucl(5l. Source: (J)B&W Technical Paper; I" DOE-NETL Scorecard On**R~huming** 61112004 (from 2004 Rebum Conference).
Tennessc"" ValleyAuLhority (TVA) Allen Slation Unil I (TN) Crushed Coal, cyclone-fired**(se~en** cyclones) 1959 vintage 

### JOO MW B&W ixliler 

### PRB &western bituminous coal bleruJ fired GE-EER Conventional 

### Gas Relmrn, 1998 startup C'AlmmerGiul instaliaLion added gJS supply piping, meLering, hangers, suppons; rclmrn injectors und cooling air piping, OFA duclwork, injection non:lcs ancl wall ports, ficld T&C devices. Reburn wilh OFA claimed to lowerNOx 65% from baseline 1.20 Ib/mmBtu 100,42 lh/mmBtu) at full load with reburn opcrmion. No claims ofpercent reborn f"cl inclucled. (TVA also installed duplicate OFA sysLems On Allen Units 2 & 3 boiler,;). Another technioal paper showed NOx lowered hy 65% from 0.E6lbfmmBtu bJseEne (to 

### O.JO IbfmrnBtu) with 7 perc""l reburn fuell'). Source: Sept. 2005 GE-EER**~xpcrience** list; ('lOOE-NETL Scorecard on Rcbuming 61112004 (from2004 Rcburn Conference). REBURN
- COAL, CONVENTIONAL Cyclone-Fired Boilers Alliant Energy (formerly Wisconsin Power & Light) Nelson Dcwey SLalion Unit2 Crushed Cool, cyclone-lired, 

### PRB cool 1962**vinl~gc**
Miankola Power Coop"mlivo,**Jn~.** A2_3 Burns & McDonnellNOx HACTAn.lysis Srudy APPENDIX A2 U.S. NOx COIln-ol Retro,,1 Proj<olS

110 MW Il&WhoikT J-cyc101l<S aero" fronl wall, 

### 4 rcbum hu,ners 

### I· 

### 4 OFAporls acro" rear w.ll, aligned vertic"lIy in culumns. 

### US nOE Clean Co"l Demonstration project of

### B&W's Conventional Cu"l RcblJrn, I991 sLartup (sJIlce**di~culllinll<:d)** 

### n<1,1c<l**~u"l** supply piping, rehum lmmers wilh nile g<lS recirelll"lio"" OFA ductwork 

### I dual ZOLle pn,1s; coal feeder, pul,-enzer & I'A f"n, I"stnl wilh PRR aod**billl",i!\o~s** coals_ (western**s~bbllllmJllOllS** cual) 

### B&W ehtimcd rebum operalio!\ lowered NOx by 57% 

### fr(}fll b<lseline of

### 0,8) mmBlo 

### I" 0.)8 Ih/mmB lu al fullloadl!l_ Apprnx. J()%**p"re~nl** oflulal fud inpul supplied as rcbumjheL Increased unil oulput by 

### 10 MW, incrcased fly",h**unbum~d** carbon by 4% (U-12% vs 9-1 R%), decreased f"macc exit gilS lernper.Hure (FEGT). 01'A ports li,ted in 

### B&W e>.pericncc lisl. D&W shows full 10,,<1 NOx w/o rcbum W'S 0_75 lbfmnilllll, and 0_29-0.J2 lb/mmHlu wI PRE fud**d,mn~** rchum operalion (57% deerease). At 75% load, 

### 0.64 vs 0.29-0.32Ib/mmBtll. Al55% lo.d, 0.62 vs 0.29_ O.J 1 Ib/mml:Hu wilhoul ,md wilh [<:burn "Cl;valcdl'). Anolhe, Icc1mioall'aper .,howed NOx lowered by 52-55% frum 0.82 Ib/mmBl<J h:lsc1illc (10 0.39-0.34 lb/mnilltu) wilh 25-**~O pero~'Tlt**  rcbum fud'i. Source, (7)2004 B&W Technioal Paper; (5)DUE"NETL 2004 Rcbuffi Con[crenee Technical paper; (OJE&W c",c**hi~lory** (from web,ilc, dalcd 1997)_


### REBURN- COAL, MICRONIZ1:.;lJ, CONYENTlONAI.**CVdOD~~Fired** Boiler.' Easlman Ko(hk CompullY Kodak Park #15 Boilcr l'mshcd Coal, frunl_wall eydonc-fircd, 1956 vintage 400,000 Ibill[ SlLonm B&W boiler ('I'pro,,_ SO MWe equivalenl, lwo cycloncs) Rr>Che.'ler. NY enslcm billlminous co,,1 UE-EEll**ml~'TomzL",1** coal rchurn I996 milial 'lartup (operaling since 1997) Demonstration project perfonned wilh Dcpl. ofEnerb'Y's US Ck;m ConI Teohnology Program. Projecl ad,led

# n"" gll,**,-e~irclll.lion** for injection mass momentum, FGR fan and Iwo micronized 00,,1 p<Jlveriu-'TS; (6) rebllll' walmJeotors added 10 rc<lr waJ]-i- (l)**r~bum** eoal injeolor Oil each ol'lhe ,idew.ll" wilil (4) UFA porls "dded**ueru,~** front w"ll "hove eyoloLle,('). GE-EER de.,igned and r<lbricated Ihe eoal**mj~"Ctors** and 01'A ports. {Extlelllely small fum"ee and lowTC,idcnce limc). GE-EER cbimed rcbum 

### + OFA w/FGR redueed NOx by 50% lrom 1.20 lblmmBllI b"scline to 0.6 lh/mmBlu. No clmms ofpercenl rebum fuel ",dud",L Anoth<:r leohnieal popor sllowed IhlS demomrrralion ofmicronized coal rebum from 4/97"10198 lowered NOx hy 57% from] .J6lbfmmBlll bosdine (Iu 0,59IblrnmBI<J) wilh 17 perocnt ,,,hum fud'l_ Source: 

### "'DOE Tupic.l R<:portNumber 14 (May 1999); GE-EER expelience lisl;15)OO£_NETL 2004 Rehurn Conferenoe Teehnic"1 paper. REBURN
- FUEL LEANGAS!U:-'HURN Cy<tone_Fircd Boilcrs MidweSI Geneh<lion (Iormerly Commonweallh Eclison) Joliel SI<llion 9, Unil 6 Cru,hed Coni, opposed-wall cydone-fired (nine cyclones) 340 MW ll&W hOller 1959 vinlage, ]997 ,Iarlup (fLGR h;,:; ,inoc been deeommi",iooed) Energy Systems Assuci;,lc> dcmunstraled 25_)0% NOx redllobon using 5-1 0% oflotal ileal input os rebum**nalur~1** g.s**i'ti~Cled** (wilhout OFAi'I_ Another tecilnical 

# 1'''1'"' showed lhis demonslr.llioll in eollahoralion wilh Go< Re,e.reh lnsiliule ofFLGR 10wlTed NO" hy 28-43% linm I.J6 Ib/mmB lu baseline (to 0.59 IblmmBlu) ",ilh 7 pcrcml rcbllm fud"). Souroe: (» DUe-NETL Scoreo,mJ un Roburnillg 6/112004 (fTom 2004**Reb~rn** ConJerenee); (10) NGB Technologie, Technical P<lpeL

Burns & MoDlllllldl Minnkot. 1'ower Cooperdtive, Inc.IIPPENDIX A2 US. NOx**Co~trol** Retrofit ProjeoL. NOx BIICTAnalysis Study

1965 vinlage Crushed COJI, froni-wall cyclone-fired (lhree cyclones) 

### REBURN

- FUELLEANGASREBURN

### wiSNCR co"ti"ued CVclone--:Fired noilers OWl-'T1sbor<> Munieip<ll ULilities 

### (KY) Elmer Smith Unit I 150MWB&Wboiler 

# cm modelstu(ly only predioted NOx reductions from L59 10 D.39lh/mmBtu with OFA only (75% reduction, 0.90 SR); 25-3D% NOx reduction lL,ing 6% oflolaI heal inpul"s rcbum natuml g"S injC<:lcd ahove OFA;**~0-45%** NO" ",duotion from SNCR with <5 ppm ammonia slipl"). Source, (U) REI Technical paper.**SeporHI~d** 

### OVERFJREAIR Cyclone--.Fired Roil

... TCIme."ee Valley AUlhority (TVA) Crushed Coal, cyclone-fired, 1959 vintage Allen SIJtion UnlLs 2 & 3 

### (TN) (seven cyclones) )00 MW B&W boilers PRE &weSIern bituminous coal blend GE-EER Overfire air (duplicale ofAllen 1), 1999 Slartup GE_EER cl"ime<1to lower 

### NO" with 

### OFA alone up Lo 29% from baseline 1.20 lblmmBtu to D.8S lb/mmBtu on UniLs U2 and 3 at full load. Source: Sepl. 2005 GE-EER experience lisL
AmerenUE (formerly Union Elc<:tric Co·l**Sio~** Unil I Crushed Coal, oppused-wall cyclone-fired 196Q vintage 500 MW B&W boiler PRE!11linois Coal blend ]Joilerhas \0 cyclone burners, arranged 

### "2 over 

### 3" styk. on opposile walls, and fires a blend of85% to 50% western subbituminous (pRB) "oal. with Illinois bituminous coal. petroleum coke, and tirc-<lerivcd fucl. A ien-port OFA system (five ports un each fronl Jnd rear waHl began operation in mid-2001, whi"h red"c"d NOx emission' appm". 40-50% reduclion from Ll-1.3 (Jssumc av=ge of 1.19) clown 10 0.7 lbi':''-ffiBtu wilh moderate cyclone**aiT_~taging** (cyclone SR from 1.IQ to 1.0). (» Subseqllenllesling and flll1load operalion al deepercyclone aiHlaging (SRs**~.90)** h:ls dropped NOx 

### wiLh SOFA alone 

### 10 around 0.3lblmmRln in 2004«1. Souce<:: Il) REI 2002 and 2003 Technical Papers; (') REI 2004 Technical**p"per;~** REl2005 Technioal paper Coal burning cyclone-fired ulility boilers in lhe United Slales**lh~l** have heen retrofitl"d with SepJrnled Overfire Air CR teohnology arc listed in Table 

### A.2-1. A large majority o[the cydone-fired boilers lisled bum western subbiluminous 

### 00"1 (or PRR blended 

### with midwestern biluminous coal).

Minnkola Power Cooper-Hive. Inc. A2-5 BWIlS & McDonnellNOK lJACr A"aly,i, Study APPENDIXA2 U.,'L NOK (''''"lrol Relrofit Projects


### TABLE A.2-1

_ Cyclone-Fired Boiler Overlire Air Retrofit Installations!"]

SCR rctrofil 511112004 SCI{ rttrolil 51OJ1200J

Similar 10 Julicl9 Unil6 SNCR demo May 2005 SCR retrofil 1211712002 SCR rmofH 6/0712002

SCR relrofit5/0112UOI 

## sm Ielrulil 5/0 WOOO SCR «IIOJil 311 0/2{}(M

# '-'~":'~;TI';lh~'**'~""m",~~=== .~'i"~,,"·~,,~"j"~"~"J."~""';'====PC~'""~"""j'j"'."~~~~~~~=-:::=1** 
.

# ~AlJen Slali"n ITnilS 1 1"".lletl

# 199~' UFA wI CGR

# relro1i";"""""'"R~ -

Allen Slati"n UnO[ 2 111'1011,,0 1999 T (Simibno Unil I, wi" C'GR) I"w SCR Allm St'lIi"n Unil3 Insl,llc..t 1999"**(.~imila,** 10 Unil I, wlo CGR) h",'" SCR A'bury UniL 1 Inslalled 511 011999 Empire Distri"t. BART-digi]'l" [J"illy lJnil 7 IJlsl<dlcJ 200.1"" SCR 10 be i""alkd in 2006-7 Umlly U"it 8 JJls<.lItJ 5/31/2000 SCR rel,ofi1511112004 lJaldwin ITnit I Inslalled 12/.,111999 SCIl 'e"o!it**412~1200J** Baldwin UniT 2 luslalIcd 51812000 SCR rel",fil4/1212002 Big Sll"'" UniL 1 l"slOlleJ 1012211997 pml orconve"ion LO PRB BL England 1Tnil2 111smlleu**199~T** prtvious SNCR TetrOLLI in 1996 Cl' wane Unit 2 J""alieu 2/111999 OFA wi CGR rtlrolit Coffetn U"il I In"alled 2111200I SCI{ relr"r,1 412 112003 Coffeen VIlli 2 ImLaIled lf9f2000 SCI{ TetrofiL 410912002 EdgewOle,Unil3 Instalkd 11(2001''') Eclg'Wl1lefUnil 4 In,talkd (j/I9/200 1 Joliel 91 1"il (, Insl.lIed 200(f") Kin"iJ UniL 1 Il1slallod 412R12000 Killc_iJ Unit 2 InSlOlled 512412000 Allen S. King ITn,t 1 In"olled 11130/1999 LaCygne Uni' I Instolled 212812000 L1ke Road U"iL (, In"alied 610112002 MichiROfl Cily lJnll 12 ImLaTled 411'J 

### )<:"" Nelson Dewey Uni1 I Imlalkd

## ,ooi'') N'lson Dewey lJIIll 2 Imlalkd 200i'" PmadJse Unit I In'tailed lll14/1998 Pamdise Unil2 In,l.lled 1218/1999 I'aradi'e Uni! J In>lalled 5/4/2000 Powe""" Unil 5-1 Inslrlllcd 61112003 l'owerl"n U"il 5-2 lnsl<llleJ 61112003 l'u",el1on Unil 6- 1 Inslall"d 61Jl2002 PoW<rlon Un" 6-2 In"alled**)/~/l999** Sdl.llfer lJIIlI 14 ImlaIIed eo,ly 2000"') Sibley UIIil] Instalkd 512412002 SibleyUrnl3 1"'lalied**51~1l999** SiOllX Unil 1 In,l.lIed 4/3012001 Sioux U"il 2 l"slalkd 4/.10/1997 Sink Lino Unil 4 Il1slolled 111200I"" TannIT.' Creek Uail 4 1llSlallttl 5/1212002 Thomas Hill Unit I 1,,'I.lled Jone 20041'" Tho",,,-, HJIl 11";12 1"'lallod November 2000"" NOle: 1 hi, l.bIc doo& "01 includc eyoryiIl"olied lJ ,S_coal_lired oyclone bOllcr OFA retrof,t pJOjecL Source: ("'US EPA DockOl OAR-2002-007(,-0446 Technical SupporrDocl1mcnl**r~r** DARTNOx I intils fur m,wjc Genemling VIIil, Iixcol Spreadsheel6/1512005**(e~repl** 0' no'od**bol~w)** • Venuurcxperionoc li,,(GE Energy lor Allen Sioliun lJniL' I-J; RJM fur BI. Ellgland I1nil2) (JlI Durns & McDonnell imemal dalaba.'o.

Cool hnrning**~ycl** une-flred "'iliIY boilers in the Unil",,] Stales lha11,avc been "'Irefilled wi Ih SCR leehnulogy are lisled in Table A2-2_ This 

### Ji." inclll<Jes a1 Ie'" eighleen eyclune-li' ed buikrs bmni"g wcslem subbiluminoU> cool (or ]'IW hlendeJ wilh midweSlern biluminous coal). The bighesl emission
lI,un' & McDonnell MinnkOLn PowerCuuporaJive, lno.APPENDlXA2 U.S_ NOx Conlrol Retrofil Projeels NOx BACfAnalysi, Slndy



# ------------- rcduclions 1i'Led in Table A.2-2 for SCR systems are for dean reactorcall1lysl and ideal operaling condilions. 

### TABLE A.2-2 - Cyclone-Fired Boiler High-Dust5CR Installations

og gn yc

, _ GmoTIllnrnam<:plale "ling, March 2002 EnergyInformalinnAdministralionreport DOElElA_0095(2000). Ac[ual unilMW OUlPUI fllliug m.ybe highc"T OT lowCT lhan namcplale_ }

_ Bum' & McDooneli inlernal da",bas<:

. •

_ " TC]lortccl 10 US EPA, available from**~lelr** websi'o ,t**hltp~/efpub.cpa.gov/gdmlindcx.cfm**
, _includes applicalion of,epal1l1ed overfiro nir rorcombuslion NOx control
, - curren! fuel believed 10be a blend ofsubbin'/l1ioou.< and biluminous coal, '_ NAO Ropublished da'" fromSCRemission testing fonnd on thcse unil,.

, , origiool ai, preheateIs were Nbular-rype; ohanged 10 rol'ry_type during SCRretrofit • _ Design NOx removal efficienoy is higher, approll. 90%_
to

_ elIITL'1ltfuel believed ro be subbiNminolls co,1 2003 07.<me Sea,nn Unil AvcrageNOx Si:r.e',M T"'lcd Onnel NO" Emi"ion Rale' F,cilily' W Tesled Conlrol Emissioo**l~~le** (lb/mmBlu) Effi<iencv' (lblmmBlu } Allen 1, 2, &**J'~** 3JO c,_ 9LlINAD'188.7 0.07O!NAD'IO.0g8 0.088/0.07710.086

D.ldwin 1'·6**OO~** 82.9 0.0/2**0.2~8**

- ---

B,ldwin**2'~** 60S'**8~.5** 0.067 0.286

D'illy 8'" 

# '" NAD' NAO' 0.84 Cofro"" 1'" 

# '"' NAO' NAO' 0.114 Coffo<Tl2M 

## on NAO' NAD' 0.120

- O,llman31&J2 

# '" NAn' NAD' 0.149/0.146



# - - Kincaid I & 2'" 660' co. 89189 0.079/0_079 0.1811Ll98 M.,ion4 

## m**94.~** 0.067 0.252



## - 

# - M'rrim:Jok**1'~** 

# '" 50.5' 0.148 0.15&



# - McrriJrulck 2 

# '" 5U' 0.155 0.171 MidiganCity 12,,10 

# '" 84.2 0.109 0.41 & Now Matlrid I &**2~LO** 600 e'. 87.4/88.1 0_149/0,147 0.JI91J.l/2 Parodi

.. j &**2'~** 704 OR. 87_7187_7 0.102/0_101 0.124/0.113

P""di,c 3"· 1150 89.1 0.088 0.658 Sdtahfer J4"'· 

# '" 83.5 0.106 0,478


## , ri inal do,; fuel for all listed c -lone boilers was biruminou, coal



### For Merrimack Unil 

### I 's 

### SCR, inlet (i.e. unconlrolled) NO

### xwas 1_34 lblmmBtu, for a blend of high sulfurbituminous and medium or low sulfur bilmninous coals, and requires year-round SCR operation for compliance. The eal"lysl wus designed for 88_9% NOx removal efficienoy

Minnkol, Power Coopc,",ive, 

### lnc. A2-7 Bum, & MoDonneilNOx UACI' Analy>i, Sludy APPENDIX A2 U.S. NOx ('Alnlml Ren-or,l Projects



### SHEeT/VB NON-CA1'ALYTICRElJUCJION Pulvcrized cCl31_lired boilers American Elcclrio Powor (AEP) Pulverizcv C,-"iI, odl·burncr, oppo.,ed wall-fired B&W hoiler ('.nrdilwl Urnl I 1%7 vinlHgc; Low NO, humor, inslalled m OctoheL' 199X (,00 MW (nolnlllal) l:lnllinnl. Ohio fuel Tech UTCH-b"sed SNCR iml"lle,1 in Oelober 1998. Fuel Tcch, DOE, EPRI·membel' ulililics SNCR**,kTllOnSlr~llOn** projeot. Tested in Malch-April 1999, clalmcd 65% reduclion with LNB, 

### + SNCtt wi 5 ppm Nil, .,Iip, (rrom prc-LNB rtlrofi! baseline nf 1.20**Ib/mml:llu~)** vown lu 0.52lblmmBlu "t 620 MW (100% MCR). SNCR**rcdlJc~d** NOx 31 

### % below LNl:l, "Ionc (0.75 llJmmlllu baseline), "I 620 MWg (100% MCR),**l~%** I'.duclion al 75% MeR**(~SO** MWg), and**~2%** reducllOn al mllllm"m 10".1 (340 MWg, 55% MUt) ::'05% "mmonia Slipl"I, b"ming e,,"lom b,lUmioou,oon1. UI'.a-lo-NOx NSR not Slalcv. SOUTce: Fuel Tech cxperience li,1 dHled 11n12005; ('IICAC Whilc Paper, 1"12000 Fuel Tech leelmical p"pcr, *Rl1cy Powcr (Babcock Powel' Inc.)**cxpcri~"T1"~** li,1 

### 811610L1. Camlin" Powel' & LigllI (PlOgress Energy) Asheville Unit I Pulverized Co"I, front wall lil'"d 200 MWe DB RJleyhoiler 19G4 vinLage, ea<lem billlminous coal, June 2000 SNCR slarrup Fuel Tech commcrci"1 SNCR m,olnallOn ebnned 25% NOx reuuction fnmllow-NOxborn" wlo OFA**baseli,,~** ot·0.58 Ib/mmllru (down to**0.4~** Ib/nnllBlu on SNCR "lone). Urca-Io-NOx NSR noj slaled. (Also**s~~** FLGR 

### + SNCR inslallalion summ"rics forpulverize;u coallmileI'S). Source: Fuel Tech experience !lst daled 1/28/2005. C.",linn Power & I.ighl (Progres" Energy) Pulvorized Co"l, TangLTllially-fired C"pe Fear Unil 5 19% vinlagc;**e,,,I~m** hilumino", coal 154 MW CE hoiler SNCR slanu]> i,,2002 Mobolee USA "Rol"mlx"**amm"ni~J_h""',1** SNCll "yslcm injecI' "'I"COOS ammonia li,!ui,l inlo a high velooily hOO<lcd sepalared overfire "ir (1<01'A) .'yslem al the hoileL CI'&L technical p"pL, c1"imedlo lowerNOx from 0.28Ib/nunl:llu ba,dinc by**~J%** 10 0.16lb/mmBllL m 2001 wilh 5 ppm NH, .,Iip 1ollowing the insl"lb(ion ufROJ'A in 2000. Overall reduclion 73% from foll"lo"v prc-ROFA baseline 0.60 Ib/nnnBlo lo O. 16 IblnunBlu'''). Mohotec daimed funher NOxreduclion

## wa.' I'0.,.,ihleby injecting urea in placc ofammonia, achieving 0.13 Ib/rnmBlu ;n,tc;Jd IlfO. 18 IhlmmFllu, wmeh woulu be 54% ueorca.,e Iiom 0.23 Ib/mmBlu with ROI'A alone, or ]X% overall dec""'I'e("I_ Ammonia·l0_NOx NSR not slaled. Source: ("I CP&L 2002**Tcch~icnl** paper; (]O) Mobolec 2003 lcchni<"lll pap". Carolina Powcr & Lighl (Prow•." Enel'gy) Pulwrizcd Coal, Tangenti,lIy-lil'od Cnp" I'oal' IInil {j [win-furnace (eight corner), 1958 vintage; C"stLTIl billlminous co,l 175 MW CE boiler SNCR slaTtup in 2001 Mobolce USA "Ro(amix" ammonia-based SNCR**~y,I"TIl,** injeds aqueous ammonia liquid inlo nl,igl, velocity boosled sep"mled ovcrfire a'r ("ROFA"') syslem at thc boiler. CP&L technical paper claimed 10 lower NOx Irom 0_23 Ihlmmlltu haseline by 22% to 0.1 lb/mmFlru wirh 5 ppm Nil, "lip following lhe insl"llation orIlOFA, "NCR in 200 11 1')_ Pccm,!alion slide g' aph shows no reuuc(ion for Rol.mi. heYOlld ROFA alone al fulll",,{] NOx cmis.,ion rale 

### of0.23 IbinlIllBlu. Ammonia_IO_NOx NSR nol "l"led. Ovemll redllclion 67% fTorn full-load pre-ROI'A bnsc1ine 0.54 Iblmmlltu 10 0_18 IhlmmBllJ. Moboleo daimed further NO, reduclion was po.,.,ible hy injecting urea in pl"ee ofammonia, ncllitving 0.10 Ib/mmBtll imlc",1 ofO. 18 lh/mmlllu, which would 

### be 56% ue"ccasc from 0.1) lblnuuHlu With ROFA alonc, or 8 I% ovcmll dccreascl'lI. Urea-Io-NOx NSR nol .'Laled. Source: '''I CP&L 2002 Technicalpapel'; I") Mobolec 200) (echnie,,1 pap.I'_
Bnm, & McDonnell A2-10 MinnkOLa Power Coopcralivc, 1m.APPENDIXA2 U.S. NO>: Cootrol Retrofil Projcct< NOxBACfAn"

TABLE A-3

-**Low-Du~t Pulve~izcd** **Coal-Fi~ed Boile~**  SCR Installations

M Donnell'mernal database. '- Current fuel is caslern or midweslern birnminous coal, exccp,lla.""" J _ US EPA Dockel**Oi\R-2002-OO7G~46Tccl1nical** Suppon Documenl for DART NOx Limil' for Elcctric Grnemling Unil' Excel Sp,."dsheCl 6115/2005, exccp' where nmed. Dale, in

## 0 "'" believed 10 be accumle bulhave notbom conlinned.

• - TI,e three valuc'S aro "Pre_control ovemge", "2004 annual**o~eTIlge".** and "2003 ozone ,"",son**"~erage"** NOx emi"inn TIlle" a, TCported to US EPA_ Prc_oontrol .nd yeOT 2004 .nnuol**a~e"ge** dato as shown in US EPA DockeIOAR-2002-0076_0446 Technical Support Doeumenl for BART NO>< I.im;l' 

## ror Electric GeIleI1lling UnilS hcel SprcaJshee16l151I005. posted on lheir web.,ile: IllIp:fldocket,epa.gov/edkpnbldoIEDKSlaffilemDelaiIYiew'lobjeeUd=090007d48084562b. V.lues 'hoWII in porenlheses "re year 2003 .nnualovemge where 2004 dal. is nol availabl". Y"", 2003 and 200] ozone ,coson data is .v",I.ble from the EPA's websile al hlto:/ldjmb.epo.govlgdmlindex.cfm, indudes ,pplicolion ofsep.",ed overlIee air for combuslionNOx control where applieable_
, - Generator nameplaleTaling. March2002 EnorgyInroITUol;on Administrolion reportDOElEIA0095(2000). AClUal uni' MW outpul TIlliog m.ybe bigheror lower Ihon namcplolc.

• - This boiler has low-NO>: burners for**~ombllSlion** control,. 7 Caroli"" Power & Lighlplanl' list"" bere have Iwo boilers per unil, lolal namcplol< rnT Mayo i, 736 MW,**Ro~boro** i' 745 MW; emis'ion numbers.rc the aVallgo ofboth boile",.

• - Thi, hoilerhas lo

....-NOx bume,. and**o~erf""** .ir for comb""ion controls.
, - Thi.' is prelimirullYdolO reponed to Ihe US EPA fo' 2004 ozone s"",,,m**.~erage** emi"'ion rdte.

,. _Thi, boiler', ourrenl fuel is belle.ed '0 be subbitnminous coal. " - Mercerboil.,,, listed have low-<iust SCRWiIh nue g"-' rehear. Unil size is approximalc, 0"1 namepl.le. NIA c<Jmplere 2004 ozone ,e"so" dala is nol .vailoble, and 2003 OWoe seaSOn d.l. is not**TCproscnlati~e** oflhe po'I-SCRinSlaHalion emis'i"nrate. 

### 'CR Unil Si,e', Operalor/Facility' Slarlup i\verageNOx Emi'.,ion 

### MW Dale" R.les· (lhlmmB'n\ AEPICo,d'lUlI Uoit3' 5101/03 0.74/0.34/0.1J5 

# ", Carolioa P&lJMayu Unit I' -/(0.J6)/N/A 368 x 2 Carolioa P&URoxbolO UniI4'" 5107fOI ll-57 10.26 10.081 372 x 2 CinergylEaSl Bend Uoill 4/01102 -1(0,28)10.067 

# "' C<m,lcll.lionIBrnndon Sho",s Unit I' (2001) 0.4710.33 10.126 

# '"'

, 

# --- ConstellalioniBraodon Sho"" Unit2' (2000). 0.45 / 03 I I 0.094 

# '"' Daylon P&UKiHen Slalio" Unil2 IIIOIIOJ _/(OAR)/0.06 

# ... Dyn,gyMidwesl GeniHavana Unil 6'" (2000) 0.46 10.20/ O. 102 

# '"

, 

# - PSEG Power LLC IMercerUnir j II (2005) -/(0.G3)/NIA 

# '" PSEG PowerliC /Merce' Unil2" (2004) _/(Q_76)IN/A 

## ''0 Bnm.'& 

# ,

MintlkOl' Power Coupcralivc, Inc. 1\2_9 

### DLmIS & McDoJUldlNOx DACr Analy';' Study APpENLllX AZ 

## ns. NOK Cootrol Rellofll Projecls



### SELECTIVENON-CA1'ALYl1CRElJUCHON I'ulvcri:wd coal fired boilers Anll'Tican Electric Power (AEP) Pulverized Coal, cell-burner, opposed wall-fired B&W boiler Cardinal Unil I 1%7 vinlngc; Low

### NO, burner, installed in (klobcr 1998 600 MW ("omim,l) Brillianl, Ohio F"el Tech urea-hased SNCR i"'lalled il\ Oclober 1998. Fuel Tech, DOE, EI'JU-member ulilil,es SNCR demunslmlion project. Tesled in March_April 1999, el"imcd 65% reductJOn wilh I.NA, + SNCR wI 5 ppm Nil] slip, (Imm pre-LNB relrofil baseline of 1.20**Ib/mmBl\l~)** dawu to 0.52 Iblmmlltu at 620 MW (100% Ml'Il). SNCR ,educed NO" 31% below LNB, alone (0.75 IblrnmBI" b",eline),"1 020 MWg (100% MCR).**3~'10** reJ\lclion al 75% MCR**(~50** MWg),**~nd ~2%**  Tl.,<Juelion al m",,,,mm load**(3~0** MWg, 55% MCR) :0% ammonia "lil,I"I, burning easlern bituminous coaL Urea·lo-NOx NSR not slated.**SOLLrC~;** F\lcl Tceh experience lisl dared**112~/2005;** (11leAC While Paper, {I'lJ2000 fucl Y,'ch lcchnic"1 paper, *Riley Power (Babwck 1'owcr Inc.) expel'iel\cc hSI 8/16104.
C"rolina Powel' & l.ig"l (Prol,'fCS> Enel'l,'Y) A,heville Unil 

### 1 Pulverized Coal, fronl wall fired 200 MWe 

## on RJ1ey hoib 1964 vinlage, easlern bimrnim'LlI cuul, Junc 2000 SNCR slart"!, Fuel Troch eummercml SNCR installatiOll chlimcd25% NUx reduclion Imm ]ow-NOx burner w/o OFA baseline**ofO.5~** Ib/mmRl" (down lo 

### 0.44 Ib/rnmlltu 01\ SNCR alone). Urc"-lo-NOx NSR "01 ."laled. (Also**"e~** FLGR + SNell mslallation summaries furpulverized coal bOIlers). Source: fuel 

### Teclo experience il,1 daled 1/28/1005_ Carolina Power & Light (Progress Enel'gy) Pulverized Coal,**"j'angenlially-lir~d** Cape T'c"r Unit 5 195(, vjntage; eOSlern hil"minou" coal**15~** MW CE boikl' SNCR slarlup in 1{)02 Moholee USA "RotamJx" ammonia.hase<! SNCll syslem injecIS aque(lu.' ammonia liquid inlo a high velucity hoo.'ted ,epawlcd uVl'Tfin; "ir (ROFA) sy.'lem al thc builer. CP&T. Icchnieal paper claimed 10 lower NOx from 0.2H Ib/mmlltu ha"eli"e by**~3%** lo 0.16 Ib/mmlltu in 2002 with 5 ppm 

### NH, slip following Ihc in"lallalioLl ofROI'A in 2000. Overall reduclion 73% li'om rull_Iond pre·ROFA baseline 0.60 lb/mmBlu 10 O.161b/mmBtu!"I_ Mol:>olcc clajmed Ii.mher NOxrcducllOn was possiblehy mjecring urea in pIucc ofammonia, achicving 0.13 Ib!LllJnfllu in,I"",1**ofO.I~** IblmmBlu, w"ich wouI,1 be 54% dec=se from 0.28 Ib/mmBlu wilh ROFA "lone, 01' 78% overall decl'easell'J. Ammonia-lo-NOx NSR nOI slaled_ Source: {'"J CP&L 2002 Technical paper; ("J Mobotee 2003 leehnical paper. Carolina Power & I,ighl (Prob'[CSS linergy)**Pulvcri~--,,<!** 

### CO"!, T"ngcnli"Hy-IITcd Cape FcurUnil 6 twin-Iumaee**(ei~ht** comer),**195~** vinl.'lge; ea'lcm biluminou" eoal 175 MW CE boiler SNCR slllrtup in 2001 Mobutee USA "Rolamix" ammonia-based SNCR sy'lem,**i,~eclS** "'Iuco", ;llnrnonia liquid inlO" high velocily bOOSlcd scp"rnled overfire air ("ROFA'') syslem "I Ihe boiler. CP&L technical paper doimed 10 lowcr NOx ITom 0_23 IbfmmBlu b"selim' by 22% 10 0. ISlb/mmBm wilh 

### 5 ppm

### NH, slip fallowing the inSlallaliun ofROI'A+3NClt in 200

### I{'"). Pn:s('ntalion slide graph shows "'0 rodu"lion forIlolamix beyond ROFA Hlune al full lo"d NOx emi""Oll rolc of0.23 IblmmBlu.**i\mmol1ia-to-NO~** NSR nol 'I;lled. Ove,all reduclion 67% from lull-load I're-ROl'A b"seline 0.54 IhIonmBru 10 0.18Ib/rnmBlu. Mobolec claJmed furth'T NOx reduclion was [Jo%iblc by inJ"eling urea in place 01" ammunia, achieving 0.10 lblmrnBlu lJl.,tead ol"O.181l>!mrnBlu, which would 

### ho 56% 

# "CC"'"'" from 0.23 Ib/mlnBI" wllh ROI'A**~Ion',** or 81 % overall decrease("). Urea-to-N()X NSR nol Slale". Source: ("I CP&J. 2002 Tc"hnical paper: 1"1 Mobol""C 2003 Icchnical paper.
13m", & MoDonneli A2-1U Mmnko" Power Cuup:ralivc. lnc.APPENDIXA2 u.s. NOx Control RotrofitPwjeoL, NOxIlACfAu"iysisSludy

Pulverized**Co~],** Tangentially-fire<!, 1%0 vintage; slarmp prior to 2000 

### SELECT]JlENON-CA TAL YUCREDUCTIONconrilluetl PUlverized coal-fired boilers Cinergy (fonnerly Cincinnali G&E) Miami I'ort Unil6 (Ohio) 163 MW CE boiler ['uel Tech urca-b"sed SNCR system, claimed to lower NO" by 35% [rom 0_55 IblrnmBlU haselinclll.(assume ea'tern biluminou< coal). Urea-lo-NOx NSR not slaled. Source: Fuel Tech experience list daled 1/28/2005, (I) ICAC White Paper. Conccliv (fonnerly Delmarva Power & Lighl) Edgemoor Unit 3**Pulv~rizcd** Coal, Tangenlially-fired, 1954 vinlage 84 MW CE boiler mid·Mareh 1996 startup; (assume easlern biluminous coal)**H~mon** Research-Collrcll supplied a**ur~.,,-b"'ed** SNCR system_ IIRC cluimcd 35% NOx rcduelion wilh 

### less lhan 10 ppm ammonia slip. Urca_w_NOx NSR not stated. Anolher source shows n )0% reduclion [rom 0.541blmmiltu basclineill

. Sourcc: Hamon experience list (not listed by Fuel Teoh); (l) rCAC While Pupcr_ Concetiv (formerly**Delmarv~** Power & Light) PulvcTized Coal fudian River Unils 3 & 4 (lVIillsboro, DE) Unil3 is front wall-fired, 1974 vinl"ge 178MW and 440 

### MW Unit 

### 4 is turbo-fired opposed-wall, 1980 vinlage B&W, DB Riley boilers Spring 2000 startup (,,"stem biluminous coal) Hamon Rcsearch-Coltrcl! supplied a ur,,"-based SNCR syslem (nOllisted by Fuel Tech) on bolh units. HRC**claim~d** 35% NOx reduclion wllh less 'han 5 ppm ammonia ,·Iip. Urea-lo-NCh NSRnol ",'led. An REI 1999 leclmical**pap~T** shows a pre-SNCR baseline 0[0-37 and 0.44 Ib/mmBtu, respectively_ (2<1) Another source lisled lhese units uS having a pre--contro1 NOx b"scline of0_97 and 0.57 IblmmBlu, and 20J)4 po,t-SNCR slmtllp average of0.32 und 0.33 IblmmBru, respeelively. (121 Soul'ce: Hamun uxperience list (not "Sled by Fuel Tech); ('") 

### ItEr 1999 technical p"P"r; 

## I"!JJS EPA Docket OAR_2002_0076--0446 Excel Spre"dshecl6!1512005. Dominion Generalion (Virginia E&I' Co.) Pulverized Coal, Tangentially-fired Oover Stalion, Unils I & 2 (VA) ABIl/CE boilers, 1995, 1996 vintalle 2" 465 MW (,,"slem biluminous coal) Urea-based SNCR (Fuel Tech syslem) 1995, 1996 startup (inilial commercial) Fuel Tech claimed NO" reduced by 25% from 

### 0.J2 Ib/mmBlU b

... ,eJine (10 0.24 lblmmBtu). Source: Fuel 

### T""h experience li,1 (bled 1/28/1005. Urea-lo-NO" NSR nol slalcd. Dyne£:)' Midwesl**Gen~'rnlion** (formerly Ulinois Power) Pulverized C.oal, Tangentially-fired Vermillion Stalion, Unil I 1955 vinlage 82 MW CE boiler, bituminous Illinois CQJl Moholeo USA uROlamix" urea-based SNCR System wilh rotaling opposed fired air(ROFA).**Mobol~c** 2004 lechnical paper claimed to lower NOx-by 55% [rom 0_211b/rnmBw baseline 10 0.10 IblmmBtu in April 2004 Wilh urea-based ROlami" SNCR and 

### < 5 

### ppm 

### CO. NH, slip nOl menlioned. Overall reduction 83% Irom fuJl-luad pre-ROI'A baseline 0.58 IblrnmBlu to 0_10 IblmmBlu I"). Urca-lo

### NOx NSR not staled. Souroe: 1")Moboloe 2004 ledmical pap<.1".

Mintlkoto PowerCoopmll;ve, Ino. A2_tt Burns & McDonnellNOx BIICTAnalysis Siudy IIPPENDIX A2 U,S. NOx Cunlrol RclroJil Projecl'

Source: fuel Tech experience li-,t daled 1/28/2005; al"" listc":! m (L)ICAC Whilc p"pc,-. (Also sec I'LGR+SNCR insl"lblion sllmmaries for pulverized coal hOllers) 

### SHl.HCTlVENON-CATALYTICREDUC110NCOII/ilmed l'ul\'crizcd coal-lind hniler. Relianl J7.1Lergy ([omK"Tly GPU Gmcu) Pulverized Cool (formerly Silhe, I;,rmerly Pelleleo) T,mgenliJlly-fired Scwanl # IS (PA) mi<l_1**~90',** SNCR Slarlup UniL, & 5 easlern bilHmiJlOus co"1 62 & 156 MW CE boiler.; I**9~O** & 1"57 vll1[Jge 1]ren.h",ed SNCR (fud Teoh ,yslem). bier inslalled all in-ducl SCR 10 reduce NH , .,Iip. Fuel Tech claimed to lower NOx 35% [0, SNCR only 

### (55% forcombined SNClUSCR rrom 0.78 IhhnmBlu**b"sdm~).** \J()iler, h"ve since been demoli-'hed and r<:pl,!Cc"(1 wilh CI'Tl&. llr"'-lo-NO" NSR nol .'l"lled_ Source: Fuel Tcch**cxpGr:icnc~** Jisl dJled Il2g1200S, (l)JCAC 

### Wh,IJ,: Pupee. Roches!,,- Gns & Eleclric Pulveri7ed Coni, Tnngenlinlly.fired Russell Slation, Umls 1-4 (NY) 1948, 1950, 1953, 1957 vml"ge 

### 1 x 50 

### MW, 2 x 65 

### MW, 1 x 85 

### MW CE boilers ea.,lem b'luminous cool Urea-based SNCR (Fuel Tech system) SNC'R sl"rtllp pnor 10 2000 Vendor claimed to lower NOx by J5-27.5% from 0.28

- 0.42 Ib/lllmlllu baseline.'. UreJ-Io-NOx NSR not sbled. Snuree; l'ue! Tceh**"xp"rieTl"~** lisl <bled 1128/2005. 

### HYD/WCARBUN-ENHANCED AMMONIA SNCR**(NOxSl"r"~** Pulverized coal_fired**boil.~.,** Tennc"te VaJky 

### Aulhorily ('JV

### 1\) Pulve, ized Coal [wi"-ILJ) nnee. LJngenllally-fi,ed, Kingston Power StatlOll (TN) 1955 \'inl"ge caslern b'luminouo ern,l Uml9, 200 

### MW" CE hoiler NOxSLJr B ' ,(urlup Junuacy 2001 Demonm:ation ofNOxSlarTM hydroo:arbon'''nh,me"r1 umrnoniJ-based SNCll i"'l"llalion. M'IS\li B"heuck e!mmod 68% NOx reduclion from baseline orO.55 Jb/mmBlu down In 0.17 lblmmBlu with boosled OFA nnd NOxSlnr'M wilh <: 5 ppm ammonia ,lip; NOxSI"r'>' "Jonc TC"(lu"c<1 NOx hy 53%(»'; boo,led Of'A only T"duted NOx from 0.55 l() OA5 IblmmBlU (18% Leduclion). Ammoni,-IO_ NO" NSll not slJted. 

### TVA', w"b,il" ",porlc,1 Ih'l "un earlier version ofNOxStar 

### wos inSlalled ol KingSlon 1'o."LI Plonl Unit in 2002 wilh mixed resulls. NO:< reduolions**wer~ ndll~v"d,**  blll Ihe boiler was dJmagcd" (l'ITp:l/www.t"'_gov/en"ironmenli"'pulm'cnvn:porlsJ"erI2003Ienv enml'lianee_htm) Source: Ill) Milsui B:ab"oek Technic"1 parer, Ocloher 2003.

. Tennes,;ee Valley Authority (IV'A) Pulverized Co"l, wall-fired Colherl 3("lion (AL) 1955 vinLag"**Unil~,** 192 MWe twin-furnJce B&W lmiler

### wIFGR**~.,.slcm** bilumll10us ooal Finl eomrncn;iol mslalblion ofNOxStarTM hydmoarlmrJ'''nhun"ed arnrnoni"-h"sed 3NCR Icchn()logy_**Mil~ui** B"b<:od( showell 80% NOx reullction from bJselllle 0[050 10 0.10 JhlmmRlu; Il.,ing < 0_1% of 10lJI boilerhe"1 inpul forpropane input and 1% O[lOI.1 SI,-Jm now generaled in the boiler for bnce ooolingl1J); 2004 SNCR sy'tem SIUrlllp. Anunonia-Io-NO:< NSR 001 slated. Source: (LJ) Milsui Bahcock 2004 Technical pap''-.



### Burns & MoDonnoll 112_14 Mi"tlkorn Powerf'oopeJaIJYc, Ino.APPENDlXA2 

### US. NO" Control Retmlit Projecls NOx BACTAnal)"i, Study

RIM claimed 50% rcdnclion from 050**IbfmmB~u** 

### pre_SNCR b.selinc to 0.251bIrmnBlu for SNCR coalfiriog operation; NOxbaseline 0.82 lhJmmBlu prior 10 R]M's LNB modificalions installed in 1994, 1992, & 1994 (39% reduction); Urea-m-NO" NSR nol slale<!. Fuol Toch c1.imou30% 

### NOx reduction for SNCR frombasoline of 153 ppm 

### firing 

### 116 fud oil on Unils 4 &60nly. Source: RlM**experien"~** 

### list, Fuel Tech**expcrien"~** 

### lisl ualed I/2S/1005. 

### SELEC11V£NON-CATAI.YJ1CREDUCTION**~OJJlirllled** 

### Pulverized "oal_fired boiler" Owensboro Municipal Ulililies (KY) 

### Pulveri""d Coal, Tangenlially-fired, Elm"" Smilh Unil2 1974 vintage 300 MW CE boil"" eastern hituminous coal Hamon Re,;eareh-Cotlrcll supplied an 

### ammonia-based SNCR syslem but slalcd noel'Lms for NO>; reduction; (this**proj""~** 

### is not listed in ICAC Whilo Paperl'J). 

### Ammonia-to-NO>: NSRnot sl"led. Source: Hamon experience lisL PECO Energy (formerly Philadelphia Electric Company) Crumby Unil I 

### Pulverized Co"l, frOnl w.ll-fired divid"d furnace 160 MWe B&W boil<:r 1954 vintage eaSICTIl biluminous coal 

### fUM inslalkd. Fuel Tech**u",~·based** 

### SNCR wilh low NO" burncr modificalions & 

### OFA in 1999, June 1999 startup.**)L!M_claj.n:te.!l_~'!o** 

### SNCRNO>; reduclion from b.seline ofO.J5Ib/mmBtu, down 10 

### 0.25 lb/mmBlu with urea NSR = 

### 0.8; 

## RJM pro';;ided**'b~~-~~'':;:;~~liii"alioosOfB&--W-'XCL** 

### fo\v-NOx 

## b\imers'i,;slalled'in

## T9iM"'+ OFA; thio reduced NOx 

### from 0.50 

### 10 0.35 Ib/mmBlu (:l0% reduclion) without SNCR. Urea-lo-NOx 

### NSR nol staled. Source: RlM 

### experience**lis~;** 

### lllrCAC While Paper. Exdon (formerly PECO EncTgy/ Pennsylv"nia Electric Comp"ny) Eddyslone Units 1 & 

### 2 Pulverizecl**Co~l Tanllen~ially-fired,**  

### 318, 33J MW eaoh CE builers 1999 SNCR slartup, eastern biluminous OlIal Fuel Tech claimed 30% NOx reduction from bnselino ofG.26 Ib/mmBlu. Source: Fuel Tech experience list daled l/l!lf20G5. 1954 vinlage

Public Servioe Enterprise Group (PSEG) Power LLC [formcTly PUblic Service Electric & Gas ofNew Jersey (PSE&G)] Huuson SL:llioll, Unit 2 Pulverized Coal, opposoo-Wlll1-fired, 1968 vinlage 660 MWe**Fosl~T** 

### Wheeler hoilereastern bituminous coal March 1999 smrtup Fuel Tech urea-hased commcrcial SNCR installalion claimed 25% (initial)NO" reduclion for SNCR ulone frombaseline ofO.651bfmmBlu (down to 0,49IbfmmBlu). Urea-lo-NO" NSR not staled. Source: F\lcl Tech experience lisl dated 1/1&12005. also**lis~ed** 

### in (I)ICACWhile P.per. (Also sec FLGR+SNCR inslallation summaries forpulverized co.1 boilers). Publi" Service Enlerprisc Group (pSEG) Power LLC [formcTly PUblic Service Electric & Gas ofNew Jersey (PSE&G)] Mereer Stalion (2) 

### lwin·fumaoe builers, 320 MWe each, Oil 

### Riley lurbo-iired Unit 

### I and Unit 2 front w.1l1'C,**we~-bouom** 

### (slagging ash) eastern bituminous**eo~l** 

### Furnace 

### 1111 & 

### #12 1960**vinl~ge** 

### April 1999 slartup Furnace #11 

### & 22 

### 1961 vinlage May 1999 slanup Fuol Tech urea-based OlImmercial SNCR inslall"llon claimed 30-35% NO" reduction from baseline 0[2.0 lb/mmBlu on SNCR alone, down 10 1.4 lb/mmlllu. Urea-to-NOx NSR nol slaled.

Minnko" 

### Powor**C""pe,"~jve,** 

### Inc. A2_13 

### BunlS & MoDonndl;"'0,, BAG Analysis :;lmly APPENDlXA2 U.S. NOx Control ReTrofil Projocl'

Souroe: Fllcl Tech experience list dalcd ]/2812005; al,o liHted III (JllCAC Wh,lc Papcr. (Also see FLGR-I SNCR in:>I"Uation summaries fm I'ulvcrio<cd coal boiler.,) 

### SELEC11VENON-CATALYTICRElJUC110N**~(JIIli/1l/~d** Pulnrllell**ro~l-Iired** boiler.' Reliant ELlerJ',Y (I", rnedy GPU Genco)**Pulv~Tized** (:0,1 (fonnedy Sllbe, formerly Penclcc) TnLlgcnli<llly-iired Seward # 15 (PA) mld-1990', SNCR st.rI"p UnilR 4 & 5 cmlcm birum1!lou, co.1 62 & 156MW CE boilers 1950 & 1957 vinl"gc lJrea-ba.'ed 

### SNCR (Fuel Tcch syslem), later iTls"'lkd "n in--duct SCR 10 reduce NH, slip. Fuel Tech claimed to lowerNOx 35% f"r SNCR only (55% for combined SNCRISCR from 0.7R Iblmm!llu h"scline). BoilcTs have since 11een demolished <lnd Iel'lace<1 Wilb eFR&. lJ"',·lo-NOx NSR 1\01 sl"lcd. Source, Fuel Tech expcTic'1lce Jist dated**1/2~/2005,** (I)ICAC While Paper. RochesIer Gas & Eleclrie Pulverized Coal, Tangenlially_lJred Ros.scll Sialion, Unils 1--4 (NY) 194R. I950, I**~53,** 1957 virltar,e 1 x 50 MW, 2:x 65 MW, 1 x 85 MW CE boilers caslern himminous c",,1 U"'<l-b,,,"'{1 SNCR O'uel Tech sy.<tem) SNCR .'IOrl,'P prior 10 2000 Vendor clalmed [0 lowe, NO. by 15-27.5% from 0.28

- 0.42 IbhnmBlu ba'elJlles_ Urea-lo-NOx NSR nol slale,!. Source: fuel Tech ""po,ienec li,1 daled 1/2812005. 

### TTYDROCARlJON-!:.JVJ-JANCElJAMMONIA SNCR (NOx.'illlr""') Pulvcrized coal_fired hnil..-s Tenne..<3ee Volley A\Jlhonly (TVA) P"lverized CoaIIWJIl-lum<lce, Langenll.lly_fired, King'lon Power Slalion (TN) 1955 vmlngo**cast~"Tll** bltllminolls coal IJmt 9, 200 MWe CF bOlkr NOxSla,TM SLarilll' Jarluary 2002 Demonslmlion ofNOxSlarTM hydr'Ooorbon-enhal1ced**amrnOTli~·bused** SNert inslallation. Mil"ui Babcock cl.imod 68% NOx reduciiOLI from bllscline ofO.5511>!mrnBlu down 10 0.17lblmmlJlu Wilh boo'lcd O}-A and NOxSlarTM Wilh 

### <;; ppm ammoma slip; NOxSl,n'J1< "lone rcduccd NOx by 53%''''1; boosled OFA only reduce,l NOx from 0.55 la 0.45 lblmmUlu (1 8% ,educIion). Alllmonia-lo**NO~** NSR nol**'~IK..J.** IVA', web,ite reported lhal "un e<lrlier versioJl ofNOxSlar WaR inslalled aI Kin!}'torl I'o"il Pbnl Unit 9 in 2002 wilh mixed resulls. NOx reduolions wcre achieved, bUllhe boilor was dam<lged" (hltp;/Iw\V\V.tva.govIenvironmCr;lIrcpoIralcnvreport,.,raed20031env_campIiance.htm) Srm,ce: (22)Mils", B<lbcoekTeclmical papcr, Oolobcr 2003.**T~'1lnes""e** Valley AUlhol'Jty (TVA) Pulvenzcd Coal. wall-fired Colbert Sliltion (AL) 1955 vinLage Unil4, 192 MWe twin-furnace Il&W boilcT w/.F(jRea;aenl biluminous coal Fir<1 commerciul inSlall<llion ofNOxStarTM hydroeurbon--enhanced**~mmoni~-bascd** SNCR lcclmolo!lY. Mil"ui Ilabcock "howed 80% NOx reduction limn l,asclinc of0.50 to 0_10 lhlmmBru; llsing < 0.1% of lO1il1 boilc, hC"1 input for propane inllOt nod 1% oflola1srenm now**g~-nc"'te<1** in Ihe boiler for lance eooling1 "); 2004 SNCR syslem slartup. Ammonia-lo_NO" NSR no! "lated. Source; (1l) Milsui Babcock 2004 Technical pap<'r.

Bum., & MeDonnel1 A2-l4 MmnkolO PnwerCoo!"'rdlive, Inc,APPENDIXA2 

### U.S_NO" Control Retrofil Projects

Pulverized**Co~l,** 

### oppo<ed wall-fired cell-bumer, 1969 & 

### 1972 vintage eastern bituminous "cal 

### REBURN

- GAS, CONJlENTIONAL Pulverized coal fired boilers Allegheny Power (formerly West Penm,ylv:mia Power) Halfield's Ferry Slation Unils 2 & 

### 3, 600 MW (nominal) encb (B&W boilers) GE-EER Gas Reburn; 1999 sLartup (Unil 2) & 

### 2003 (Unil J) GE-EER Low NO" burners, boosted OFA, gas reburn system. (jE-EER clnimed lO lower NO" up lO 67% from b"scJine of0.60 Ib/mmBtu 10 

### 0_20 lbfnnnBtu at full load Wilh relmm operation on Unil2, 68% from 0.62lb/mmBln to 

### 0.20 IbfmmBtu on Unit 3. No claims of percent r"bum fuel included. GE_EER teclmicaJ paper shows appro". 35% NO>: reduotion at GOO MW 

### load mth LNB 

### + OVA wlo 

### reburn fuel, 'md nn addilional 50% reduction lo 0.20 lblmmBtu with rebtlrn fuell")_ B&W added 20 OFA porls in 1994 

### per B&W's experienoe list. No NOx reduction claims. Source:**S~l'l.** 

### 2005 GE-EER cxpcrience li'l: (!OJ OE-EER 2004 Te"hnical puper. Unit 2 and Unil 3 li,ted in l'IDOE_ NEIL 

### Scorecard on Reburning 61112004 

### (from 2004 Reburn Cooference). 

### REBURN

- GAS, CONVENTIONAL co"ti"ued Pulverized coal-fired boiler.•) Conecliv (fonnerlyDclmorva Power & 

### Light) Pulverized ConI, Tnngemially-fired Edgemoor Unit4 1966 vintage, eastern bituminous conI 160 MW 

### CE boikT 1999 slarlup

. --·GE-tiliR-OasRebu

### nJ projecta<Jili,d gas supply**pijJm~r;ietef1** 

### n-g;lfatiger-s;-

### supports;-reburtfiu j

### eotill;;""<iJid n 

### cooling air piping; OFA duolwork, injection nozzles and wall 

### ports, field inslrumenlmion. No FGR Or OFA booster fans_ Vendor claimed to lower NOx up to 48% from baseline of0.32 IbJmmBtu to 0.16IblmmBlu) at fu1110ad wjth 

### rcbum operation. No cluims ofpore""l rcbum fuel included. GE-EER technical p"per shows approx_ J2% NOx reduotion for gas rcbum with 4-mill operalion at 160 

### MW lood from 0_3 

### I IbfmmBlu 

### LNB 

### + OFA buseline 

### wlo rebum fuel (down to 0.21 IblmmBtu), and 

### 48% NOx 

### reduction for 

### !,,,,s rebum Wilh 3-mill operation, to 0.16 IbfmmBtu (2<J. Source: SepL 2005 OE-EER e"penenee lisl;l2') GE_EER 2004 TeclmiClll paper_ Listed in "IDDE_NETL Soorecard on Reburning 6/1/2004 (from 2004 Reburn Conference) Dynegy (fonnerly Illinois Power) Pulverized Coal,**Taugcnli~lly-lired** 

### Hennepin Unil I 

### 1966 vintage 71 MW 

### CE boikr eastern bituminou" co"l GE-EER Gus Rchurn, 1990 startup (not currently opcIUling); GE-EER Orirnulsion Rebum, 1997. D9E Clean Coal dcmonstr.t;on projeol (included sorhont injection). Vendor cloimed gas rehum 

### wi OFA lowered NO" up to 67% from buseline of0.75 IblnnnBtu to 0.25 Ib/mmBllI) at fuJI load; 65%reduclion from baseline of0.75 lbfrnmBtu down to O.261blmmBlu with subsequent Orimulsion rebum operation. GE-EER 2004 technical paper shows 18% gas reburn fuel yielded minimum NO" emissions('J. Another lechnical p3per showed this 80 MW US 

### DOE Clean Coal demonstration project in January 1991-**J"nu~ry** 

### 1993 lowered NOx by 67% from O.75lb/mmBtu baseline (lO 0_25 lblmmBln) with 18 percent rebum [uell5). Source: Sept. 2005 OE.EER experience list; (6) 

### GE-EER 2004 Technical p3per; l')DOE_NETL 2004 Rcburn Conlerenee leolmical pUp<.', and DOE-NETL Scorecard On Rebuming 6/1/2004 (from 2004 Reburn Conference). (Also see Conventional Oil reburn installation summaries for pulvlTized cooI boilers).

Minnkol. PowerCooperalive, tne. A2-1S 

### Dum' & 

### MoDonnellNOx BALI' 

### Analy.i, Sludy APPENDIX A2 II-S. NOx CDnlrol Rclrolil Projecls



### RJWURN

. COAL, MICRONIZED, CONVENTJ()NAL comilllled Pulverized cool_fired boil.r

.. E ON US Boldin!!:> (fonnerly !'ouj,vJlle Ga" ond Elechic) R.I).**Gre~n** 

### Slnl,on Units I & 

### 2 (KY) wall-flred, plLlverized coal, vinlagc unknown 293 MWe, 2 boilers**~:"lern** 

### billlminous coal GE-EER cuul rehurn 'yst"m Sl0l1UP dale." 2003 & 

### 2002, rcspeclively Vcndor doimed lo lower NOx up lo 

### 57'Y, I,orn hasellllc orOA5 lb/mmBlu 10 0.20 Ib/nllnBllL at full load Wilh rehum O]JLTdlion. Rchorn 'yslcm li'ICt! on EPA's "Scorecard un Rchominr, 611/2004" shows**NO~** 

### lowcred hy 44% [;-om bo",linc ofOA5 lhfmmllllL down 10 0.25 Ihlmmllm (Wllh unknown rebnrn fnel**inpnl('~.** 

### Anolher lcclmic:ll p"per**~howe<1** 

### ba,cline NOx wilh exi:;ting**10w_NO~** 

### bllmclO wu:; 0.45 IhfmmBlu, tl11l1 reduced NOx em'.«ion 40% [0 0.27 Ihimmlllll Wilh OFA, and**furlh~r** 

### reduced NOx emis.,ions 21% down to 0.21 Ih1nnnl:llu Wilh the cual rcbum syslem in opcr;Lliun". Source; I') DOE-NETt Scoreeard On Reburning**611!200~** 

### (Jiom**200~** 

### Reburn Conference): 1"1 GE Energy 2004 Technical paper, and (20) 

### M:lrch 2004 Mudem Pow"r Syslcms**issu~.** 

### Cheng Loong (not iu Unilcd Slale,) IInil I;'

### I, 250 MWe wall-fired, bi(uminou, pulverized coal, vinlage & 

### mfr unlmo"",, GE-EER coal rebllrn syslem 2000 Slartup (s(ill operaling) Source, CoE-EER expel'ience li"t VemJor cbimed 10 lower NOx**~4%** 

### from**b~selin~** 

### 0,45 IhlmmRtu 10 0.25 lillmmnln) al lull load with OVA alone: further ,educed NOx**2~%** 

### 10 0.1 Ihfmnillill. for 60% ovcmll redllcllOn. Recenl (2004) Jata sbows NOx ,lown 10 0.14 Ib/mmB III 

### (69% Qvcrdll) wilh up lO 30 perOenll'elmm liJd"). Sonree; (") Col' Enel'gy 2004 Teohnical paper: GE-EER experiencc lisL Lisled in (» 

### DUE-NIo'l'L Scorecard on Reburning 6/1/2004 (from 2004 Reburn Confcrencc).
REBURN
- GAS, 

### CONVEN110NAL 'v SNeR 

### 1'"lvcrlz,'d cual_lIre,] boilers) NRG Somer"et Pulverized Coal, T"ngcnli""y-fircrl, vinlage Unil6 Builer (NY) 

### GE_EER CO<lvenlional Gas Rebllm, 120 MW CE hoiler Fuel 'feeh SNCR, 2003 'lartup Rehum vendOL claimed to lower NOx 55% Irom 0,45 lb/mnillill baseline 10 0,20 Ib/mmBlu"1 fuJlloaJ w,lh rchum opm'lion burning VC'Tlcwd:m c()ul. Thc SNCR 'y.'tem lurlher**redu~ed** 

### NOx emi"lon, 45% ,10wn 100.11 IhlmmRlU, ior an ove",]] redllclion 01'77%.('"). SOUlce: Sep!. 2005 GE Encrgy**c~pericncc** 

### IoSl; (10) Murch 2004 Modem**Pow~r** 

### SyolenLS Jssue. REBURN
- FUHL LEANlJ"AS REBURN(FLGR)**1'"1,,,'~jzed eoal_li~ed** **boile~.,** 

### Dnke Power CompJTly langentially-fired, pulvcriv.:<J coal Rivc"Thcnd Unil 7 ea"lern bilUminou" coal 1954 vintage 140 MWe, CE boiler 1998 FLGll slartup:gas rebum rlttOmmioslOnerl sincc lhen Previously in,Lalied ARB/CE's I.ow NOx Concentric Firing System (LNCF:>-I) Wilh Close-Collpled**O"erfir~** 

### Air (CCOFA); (pre-mod NUx'l combustion mods dalc nOl known). Commercial FLGR inRlallalion daimed34% NOx re<luc(]on from fulJ-Jo:ld b.sdinc ufOA2 IbfmmBlu do\\'Tl III 

### 0.29 IbfmmBtn w/lhe comhu.<lion modJllca(]ons and l'LGR gas rebum fuel at 7% oflolaIboiler heal mpuL CO emi"ion,**W~"TC** 

### above 1000 ppm cOITeclccllo 3% 0,.1"1 V''Tl<Jur claimed lO lower NOx 57% from OA71b/mrnlltn ha.,eline 10 0.20 Ih/mmllln) al rullioad Wilh seraraled OFA alonc; furlhcrrcduced NOx**~5'1'0** 

### 10 0.11 IblnunBlu wilh 10w"NOx**bUm~T",** 

### OFA, gas [cburn, and SNCR, lor 77% over.1I rccluction; nu c]UlIT'" lor amon", orrehllln I"el{"'.

Bum> & 

### McDonnell**i\2·1~** 

### Mumkul. Puwer Cuoperdlivc. Inc.APPENDIXA2 

### U.S_NO" CoolfOl Retrofil Projects NO"DACfAn,lysis Sludy



### REBURN- OIL, CONVENTIONAL Pulverized ooal:fired 

### boilers Dynegy (formerly Illioois Power) Pulveriz<:d Coal,**T3ngen~ally-fircd** 

### Hennepin Unit 1 1966 vintage,**c~l'1ern** 

### biluminous coal 71 MW CE boiler 1997 slartup GE-EER Orimulsion Rebum syslem wi OFA, c1.ime<1 arimulsion reburn lowered NOx up La 

### 65% from baseline of0.75 lbimmllLu to 

### 0.26 lblmmBlu al fun load wilh Orimulsion reburn operalion (m3talJed Jner gas reburn**WJ~** 

### demon.<lraled in early 1990's). No clJims for percelll reburn fuel induded_ GE-EER 2004 leohnioal paper shows 60% reduclion wilh**~ubs<XJuenl** 

### 06mulsion rehum 1'). 

### Source: GE-EER experienoe lisl; (') GE-EER 2004 Teohnical pJper. Orimulsion not mentioned in (5) 

### DOE-NETL 2004 Rob"rn Conrerence tedmic"1 pupcr or DOE-NETL Scorecard 00 Reburning 6/1/2004 (from 2004 Rcburn Conference). (Also**~~"C** 

### Conventional G", Rebum iostallalion summarie, for pulvcrin,d coal boilers). New Brunswick Power Coleson Cove, Bunker C10rimulsion-firecl, oppo3ed-wall S1. John, NewBrunswIck, CanadJ 3x 350 MW B&W Boilers Sixlcen new low-NO" OlJlOrimulsion burners, eightreburn burners, nine SOFA ports. two eombmrtion air boosler**[un~,** 

### reburn and OFA wall penelralion opening,;, OFA windboxes, ductwork, dampers, "nd accessories**w~-re** 

### added!]). -Anolhcr_lechnical.pJpeLshowclllbis reburn syslem !owcred.1,rax by78%Jrom.J_0 lbfrrunBtll**ba~elill.c ~.**  

### 0.22 lbJmmBtu.1 25 percenl rebum fuel input l'). Source: 0) 

### B&W 2004 Technical Pnper,IS) DOE-NFrL Scorecard On Reburning 6/112004 

### (from 2004 Rehurn Conferc"lIcc). Gcorgia Power Pulverized Coal, TaogeolialJy-lircd Scherer UniL 1 1982 vinlage -887 MW CE boiler 2000 oil rebum starrup GE-EER 011 Rebum syslem, claimed to 10werNOx from baseline of0.36 lb/mmBtu_ GE-EER 2004 Technicall'aper shows reduction up La 48% (10 0.19Ib/mmBtu) al800 MW load with oil rebum operation. No**cJaim~** 

### ofperoent reburn fuel included!"'). Souroe: Sept. 2005 GE-EER experience**li~t ~hows**  

### Ihis as a**co~]** 

### robum project wilh eliSlem biluminous coal, reducingNO" emissions 33% rrom 0.36 to 0.24 lblmmBtu; (N) 

### GE-EEIl2004Teohnical paper. Not liSled in I') DOE-NETI. Scoreoard on**Reburni~g** 6/1/2004 

### (from 2004 RebuTTI Conference). 

### REBURN- COAL, M1CRONlZED, CONVENTIONAL**Pulve~jzetl eoal_li~ed**  

### bOilers AES (formerly New Yark SI"le Eleelric and Gas Milliken Stalion Unil 1) Cayuga langenLially-fired, pulverized cool, ] 956 vinlage 148 MWe, CE boiler easternbjUlminous co.1 GE-EER mjcronired coal reburn syslem ]996 Slartup (still opcroling) US DOE Clean Coal demonslrnlion project from March 1997-April 1999 lowered NOx with this rebum system by 29% from 0.35 Ib/mmBtu baseline 10 0.25 IbfmmBtu at i4 percenl rebum fuel inpul!'). Nol lislCd in GE-EER's expericnce lisl nor iotheir2004 lechnical paper. Source: (') DOE-NEfL 2004 Reburn Conference lechnicJI paper and DOE-NEIL Scorecard on Rebuming 6/1/2004 (from 

### 2004 Rebum Conference).

MinnkOl' power Cooperalive, lne. A2_17 

### Bnm' & 

### McDonnellNOx BACT Afialysis 

### Study AJ'PENDLXA2 II.S. 

### NOx Control Tlelror,t ProjtCIS



### RE811RN

. COAL, MICJWNIZED, CONVENTIONAL ("vllli-II"ed Puh'crized coal_lired**lJoil~n** E. 

### ON US Holdings (formerly Louisv,lle Gas and Eleclric) RD. 

### (ireen Slation Unils 

### ! & 

### 2 (KY) 

### wall_lired,**rIlTv~'Tizc!l** 

### coal, vinlage unknown 293 MWc, 2 bOIler" easlern blluminous coul GE·EER cuul rebum syslem Slarllip !lalcs: 200J & 

### 2002, respeolivdy Vendor daimcd LO 

### lowcrNO" up 10 57% Irom hnseline of0.45 IblmmBlu 10 0.20 Ib/mmDlu aI 

### 1'ull]oad wilb rebum opcTotion. Rd,,'rn**~y'km** 

### lislcd on 101'

### A's "Scnrccllul un R"b"ming 61112004" "how$ NOx lowL.,-eu by 44% from baseline of0.45 lh/m",Blu down lo 0.25 lMnmfilu (Wilh unknown rcbum fud input(>'). Another Icchnic.1 paper showed**hn~elinc** 

### NOx wlth exisling 10w-NOx hurners Wa, OA51blmmBlu, and reduced NOx emlssion 40% 10 0.27 Iblmmfilu Wilh OF 

### A, alld lurtherr"uuccd NOx emissions 22% down 10 

### 0.21 IblmmBl" wilh lbe coal rehurn 'yslc"Tll in operation". Sou, ce, (j) 

### nOE.NETL Scorccurd on Rebul'Iling 6/112004 

### (from 20041tcbum Conference); 1"1 

### GE Encrgy 2Ull'! Technical pap'-"!", ,mu ",j Mareh 20U4 Modem Power Syslems i"ue. Cheng Loong (nol in United Stale.,) Unil #

### 1, 250 MWe wall-fired, bilummous pulverJ7.ed coal, vml"gc & 

### mfr uulOlown GE-EER co,,] rcbum system 2000 Starillp (slill opcmling) Source: GE-EER eXljerie"oc li81 Vendor chimed 10 lowcrNOx 44% from hasdine 0.451blmmBtu 10 0.25 Iblmmlltu) at rul! load w,'h OFA nlone; f1ll1her reduccd NOx 28% 10 0.18 lb/mmllll1, lor 60% ovcrall rcuuclion. Recent (2004) dnla shows**NO~** 

### duwn lu 0.14 lb/lllllllJtu (69% nvcmH) wilh up lu 30 pcrcenl rebum Jucjl-"I. Source: I") G1'. 

### Energy 2004 Teehlllcal pape,; GE-EER eXI,erie"oe**li~l.** 

### Ll,I,·u m ('J 

### DOE-NETL Sco,ccn"l on Rebuming 611/2Ull'! (from 2004 Re1J1lm Confcr<-"T1c").**Rh~BURN-GAS,** CONVENTIONAL wSNCR l'ulveri'.ed conI_lire,! 

### boil,'nl l'.'RG SumlT,cl PUlwrizcd ("0;11. T,mgc"Iltiully-lired,**vml"g~** 

### lJmt (, Boiler l( (NY) 

### GE-loER Conventional ('os Rehu(n, 120 MW CE boiler I'uel Tech SN("R, 2003 slm1up Rcbum vendor claJmed ,olower NO" 55% ITom 0.45 Ibimmlliu ha,el;nc 10 0.20 lbimmlliu 01 fulllo.d wllh rcbum operaliun bllmmg Venezuelan**~o"L** 

### The SNCR 'YSIClll furlher reduced NOx crnisoion' 45% uown 10 0.11 Ib/mmfilll, for all ovcr;lll Tc<!ucl,on of77%.l'O). Sourcc;**S~"pt.** 

### 2005 GE Energy experierwc h,'; ("I M'lTch 20ll'! Modem Power SysltmS ios"c. /{£'lJURN

- FUl:;L LEAN GAS

### REHURN (FLGR) 

### 1'1Ilveri1.ed coal_lirerl**hoil~,.,** 

### Duke Power Company lallgenliully-fircd, pulverized coal RiverheJld Unit 7 casIei'll billlmil\ous coal 1954 vinlagc 140 MWc, CE boiler 1998 FLGR "Iartllp,.gas reburn decommi"ionctl Smce Ihen ]'reviou"ly in'lalled**ABBICE'~** 

### Low NOx Concenlric Firing System (LNCFS-I) with C1ose-Couplcd Overfirc Air (CCOFA); (pre-mod NOll + 

### combu"'ion mod" dale not known). Commcrc",1 FLGR installation claimed 34% NO" rcuuclion ITom full-load b"-'eline ofOA2 lblnmlH(u down 100.29 lblmmBru "II 

### lhe combuslion modiiicalion" and FLGR g.o rcb"m fuel al 7% oriola! boiler hoal inp"t. CO cmi",;ious werc above 1000 ppm correclcd 10 3% o,.IZI' V<:ndor cl.imed 10 lower NOx 57% from 0.47 lb/mmBlu ba""line to 0.20 lblIUJIlHlu) al full load wilh ""pnnllc"<1 OFA alonc; furtherreduced NOx 45% 10 0.] 1 lblmmBlll wllh**low-NO~ b"m~T',**  

### OtA, ga" rehum, and SNCR, lor 77%**o~cmll** 

### reduclion; no claim' ior amounl ofrcbum 

### fuej!"'.

Bul'O" & 

### McDonnell A2_1S 

### MinnkoIO PowerCuupor.rlivc, Tile.APPENDIX A2 U.S. NO>< Conlrol RetrofitProjects NO>< BAefAnalysi, Study

-."**-~_.** EPA's "Scorecard on Rebuming 

### 6Ilno04"showed this rebum syslem lowered NOll by 25-30% wilh 5- 10 percent reburn fuel inpul('I. Source: (21) ESA, GRI, NGB 1998 Technical paper;(2<) GE Energy 2004 Technical paper; <') DOE-NElL ScorcCllrd on Rehorning 61112004 (from 2004 Reburn Conference). 

### REBURN

_FUELLEANGASREBURN(FLGR) eonl;rlU<'d Pulverized coal-fired boilers Wisconsin Electric Power Company (WEPCO) Pleasant Pi<lirie Unit 1 Oil Riley, lurbo-fired PC, PowderRiverBasin coal 620 MWg 1980 vinLage ,1999 startup Fuel Tech lisled FLGRinsLallaLion and claimed 20% NOx reduclion from ba.'<Cline of0.45lbfmmBlu (10 0.)61bfmmBtu). No claims ofpercent reborn fuel inpul included. Source' Fuel Tech experience; listdaled 112812005. ('J OOE-NETL Scorecard on Rebuming 61112004 (from 2004 Rcbum Conference). (Also see FLGR

### + SNCR insLallalion summaries forpulverized COJI boilers). 

### REnURN

- FUEL LEANGASREBURNw/ SNCR (Amine-Enhanced

### FLGR) Pulverized coal-fired boilers Carolina Power & Light (Progress Energy) Asheville Unil 

### I Pulveri7,.ed Coal, from wall fired 200 MWe DB Rileyboiler 1964 vimage, eastern biluminous coal, June 2000 startup Commercial urea-hased Fnel Tech SNCR +FLGR inslallation claimed 50% NOxreduction from baseline ·ofO:58-lliImmBru(426-pPnijuowrHo-02inbJ'mmBtu 

### wI51>pm arnrnonia·slip(l). -towNOx·burners were previouslyrelrofiUed in 1997 witOOul

.... l>'I[1ltedovernre ai.-!"l. 

## 111" is )] % lower lhan 0.44 lbfmmBtu baseline for SNCR alone. (Also see SNCR inslolIalion summaries forpulverized coal boile"'). Ur

...-loNOx NSR nol sLaled_ ,; EPA's "Scorecard on Reburning 6/112004" showed this SNCR--enhaneeu reburn sy,lem lowered NOll by 25-30% with 

### 5-

### JO percenl rebum fuel inpul in 2000, bul not eurrenLly operJting

### l'). Another leclmical paper showed 52% NOx reduction down 10 0.28lbfmmBlu at all loads, from 99 MWg to 207 MWg (48% 10 100% MCR) with an average NH, slip of) ppm. FLGR alone achieved 2)% NOx reduclion wilh 6% rcbum fuel and < 400 ppm CO at 

### full load. (1') Source: Fuel Tech experience lis!, (l)ICAC While Paper; (') DOE-NElL Scorecard on Rebuming 61112004 (Jrom 2004 Rebum Conference); ("l CP&L and Fuel Tech 2001 Technical paper. (Also sec SNCR installalion summaries forpulverized coal bOIlers). Public Service EnlCTJlrise Group (PSEG) Power LLC [formerly Public Service Elccuie & Gas ofNew Jersey (PSE&G)] Hudson Stalion, Unit 2 Pulverized Coal, opposed-wall-fired, 1965 vinlage 660 MWe Fosler Wheclerbollereastern biluminous coal March 1999 staJ1up Commercial SNCR + FLGR urea-based Fuel Tech installalion c1Jimed 40% NOx reducllon 

### frombaseline of0.65 IbtmmBlu (down 10 0.39 Ib/mmBlu) 

### wI 10 ppm ammonia slipll). This is 20 % lower than 0.49 IbfmmBtu baseline for SNCR alonc. Urea-lo·NOx NSR nol stated. EPA's "Scorecard on Rebuming 61112004" showed lhis SNCR--enhanccd reburn syslem lowered NOxby**25-~0%** with 5-10 percemrebum fuel inpul in 2000, bul nol currently opernling('l. Source: Fucl Tech experience list, (l)lCAC While Paper;t'l DOE-NETL Scorecard on Rebuming 61112004 (from 2004 Rebum Conference). (Also see SNCR inslallmion summaries forpulverized coal boilers).

Minnkola Power Cooperative, lnc. 1\2-19 Bum. & McDmUl.U

### RERURN

- FUELLEANGASRERURN

...ISNCR (AnrilJe_En1lallced FLGR) continaed Pulverized coal_lired boilers Pnblic Service JOnlerprise Group (PSEG) Power LLC [formerly Public Service Electric & G"S**ofN~'W** Jersey (PSE&(;)1 Mercer Sl"lion (2) twin-furn""c boiler:;, 320 MWe each, OIl Riley lurho-fired IJm! I and IJnit 2 Ironlwall PC, wet-holtom (slagging ash) easlern bituminous coal Furn;,cc 1111 & 1112 19G0 vinlage M"y 1999 "Iarlup Furnace #21 & 22 1961 vJn1.age May 1999 slartup Commercial urea-ba.'ed Fuel Tech SNCR 

### + FLGR**inslal1a~on** claimcd 

### 60% NOx reduclion from b",;clinc of 1.4 IhlmmBlu (down 10 0.56IblmmBtu) 

### "II

### 5 ppm.ammonia slip m This i.' 

### 72 % lower than 2.0 Ib/mmBtu baselme wiLhout conlroL Initial demonstralion ofAEFLGR "oinjcclcd .minc-cnh;mccd natur"l gas into**Furn~ce** 22 in 1998. Subscquently inst"lbl AEFLGR on holh unJL, 10 reduoeNOx staning in May 1999 using (2) levels ofAErLGR retraclable ga" injecLors and (2) levcls ofSNCR injeclor"I>9I_ Urea-lo"NOx NSR nol "["lcd, goal was NSR< 1.25. [Nolc bolb unil_ have 'ince heen relrolltled with low--<lust lail-end SCrb in 2004; SNCR systcms UTe slill capahle and uperaLcd as ncc-<led, moslly for ny"sh condiIioning 10 aid ESP perform.ncel EPA's "Scorecard on Rehurning 611/2004" showed lhis SNCll-enhanccd n::burn sysLem luwenil NOx by 25-30% wilh 5-10**p~TCCnl** rcb"m fuel inpul in 1999, hut nOl currently operating('J. Source: Fuel Tecb experience**lis~** ('JICAC Wb,le Paper; ('") I'SE&G, 

### IT and ESA2000 Technic"l p3l'el';('1 DOE-NETL SCUTl"C"ul on Reburnin1l61112004 (from 2004 Rehnrn Conference). NOx BACTAnalysis Srudy APPENDIXA2 U.S. NOx Comrol Retrofil Projecls



# ,

# . j 

# Cl d



# ,,

, -j

Wiseonsin Electrio Power Company (WEPCO) Pleasant Prairie Unil I DB Riley, turbo-fired PC, Powder RiverBasin coal 620MWg 1980vinlage 1999storlup Fuel Tech urea-h

..,ed SNCR +1'l.GR demon<lralion inslallation claimed 56% NOx reduction from bnsellllC 0[0.45 IblmmBlu Lo 0.20 lb!mmBlu "115 ppm .mmoni" slip(l). This is 

### 44 % lower Ibnn 0.36 Ib/mmBlu haseline lor FLGR alnne. EPA's "Soorce"r<l on Reburning 6/112004" "howed Lhis SNCR_enhanced reburn sy'lc"TTl]owered NOx by 25-]0% with 5-10 percenI rehurn fuel input in 2000, bul not cUiTenllyopern1ing(5J

_ Sour",,: Fuel Tech experience li,t, O)ICAC WhilC rupee und F.T. experience list 0207; ('J OOE-NETL Scorec.rd on Reburning 61112004 (from 2004 Reburn Conference). 

### LOWNO. BURNERS (Repincemem ormodijicmioJLS) wiaJJdw/o OVERFJREAIR Pul"erizetl coal-Iired boilers 

### AEP Cardinal Unil I Pulverized Coal cell-burner, oppo,od "lull-fired B&W boiler 600 MW (nominal) 1967 vinlage; Low NO, burners insmlled in October 1998 Producc<:l 0.75 lbfmmBlu NOx pust-LNB iru;"'11 b.oclinc aL [ull load_ LNBs reduced NOx 57% from 1.20 down to 0.52", produce NOx at "pprox_ 0.57lh/mmnlu at min. load wlo SNCR (range 0_51 100.65) and produce 0.751b/rnmBLll NO" al approx. 585 MW (top ofload r"nge tested, NOx range 0.73 to 0.861b!mmBlu)(l1). (50) original B&W circularburner" were recenllyrcpl""cd on Cardi""l Units 2 & 3 by Buckeye Powe, with OIl Riley (now Ftabcock Power) CCV type low NOx bumers. Source:**~Riley** Power (Babcock Power Inc_) RlI (,/04 exrerience lisl; (7) 2000 Fnel Tech technical paper. (A1:;0 """C SNCR irl.';tallation sunu""ries for pnlveri""d coal boiler"). C"rolina Power & Light (Progress Energy) A,heville Unil j PulveTIzclJ Cu"l, [ronL "lull fired 200 MWe on Riley boiler 1964 viLltage, ea.,lern hilumiLlou._ coal, June 2000 'l.rtup Low NOxburners were previously retrofitted in 1997 without separated overfire**ai~"I.** NOx reduction was 46% [rom pre-LNB inst.ll,,'ion b"sclinc of 1.081blmmBIu (121 down 10 O.58lb.lmmBtu (00)_ 

## "·l , j


# , J 

# J

Dums & McDonnell Al-20 Minnkota PowerCoopcralive, lno.APPENDlXA2 U_S. NOx ConlIol Retrofi( Projec1S NO" BACfAnalysis Study

(Also see SNCR, and FLGR with SNCR installation summaries for pulverized coal hoilers). Souree: 112)2005 US EPA Docket OAR-2002-0076-0446 Technical Support Documenlspread.,heel; I") CP&L and Fuel Tech 2001 Technical paper. 

### LOWNO., BURNERS (Repluc£nteJll ormodifica/ion.<) wIaud w/o 

### OJ/ERFJREAIR COlllin"ed Pulverized coal-fired boilers Carolina Power & Light (Progress Energy) Pulverized Coal, Tangentiully-fired Cape Fear Unit 5 1956 vinlage; eastern bituminous coal 154 MW CE boiler ROFA startup in 2000 Mobo,e. USA's Rotating Opposed Fire Air (ROT-A),is a high velOCity boosted separated ovcrIire air system claimed to lower NOx wilhout retrofitting 10w-NOx burners. This was the firsl U.S. inslallation of Mobote. USA's "Rotating Opposed F,," Air" (ROFA) On a ulility boiler, which ulllizes a booskr fau. CP&L technical paper claimed to lower NOx 53% ITom full-lo"d pre_ROFA baseline 0_60 Ih/mmBlu 10 0.28 lbfmmlllu wilh ROFA alone following lhe install"tion ofROI'A in 2000("). Source: {HI) CP&L 2002 Technical paper. (Also see SNCR installution summaries forpulverized coal hoilers). Camlina Power & Light (Progress Energy) Pulverized Coul, Tungentially-fired Cape .FearUnit 6 lwin-lilrnac-e (eight comer), ]95B vinLage; eastern bituminous coal 175 MW CE boiler ROFA staTiup in 200] This unil's "ROFA" system was installed as part ofa "Rotamill" SNCR 

### + ROJo'A system. CP&L technical paper 'hows ROFA alonereduced NOx 57% from fuJi-loud prc-ROFA haselinc 0.54 lb/ri1mEiilil(la-NOxemiS:,ion

### niie oHJ:2J·llifmrnHtil---:-

### I")·-

_ .. ---- Source: I") CP&L 2002**T~..,hnical** paper. (Also 

### see**~"'NCll** installation summaries fur pulverized coal boilers). Coneeliv (formerly Delmarva Puwer & Light) Indian River Units 3 &4 (Minsboro, DE) Unit 3 is [mnt wall-fired, 1974 vintage 17HIylW and 440 MW Unit 4 is turbo-fired opposed-waH, 1980 vintage B&W, DB Riley boilers euslem bituminous coal RElperronned CFD modeling OLl hoth units for potential SNCR upplicatlOn. Unit J has Riley Low NOxburncr>; (16), (R) front wull and (R) rearwall OFA pons, (8) wall boundary air ports, (66) side wall OJoA SIOIS, clallned baseline NOx around 0.37 lb/mmHtu 

### w/o SNCR 1101_ Unit 4 has (24) front and rear wall down"nred burners, (28) front and relIT wall SOFA paris, clulmed NOx uround 0.44 lbfmmBtu 

### w/o SNCR (W) (furnace has "Mac West" belt}. Riley provided 16 CCV**low-NO.~** humers for Unit 3 in 1994, und cl"imed to "educe NOx emissions by 67% from pre-LNB baseline of 1.051b/mrnBlu down to 0.341b/mmlltu. Source: 

### 1'°1uoI 

### J999 Technical Paper; Ril,"Y Power (Babcock Power Inc.) 

### 8/16104 experience list. (Aloo see SNCR inslallation summaries for pulverized coal boilers). Dayton Power & Light Pulverized Coal, Tangentially-fin-d Killen St:ation, Unit 2 1955 vintage 632 MW CE boiler, bituminous Illinois coal GE-EER provided low-NOx burners in 1999. Vendor claimed full load NOxwas reduced by23% from a 

### 0.57 Ih/mmBtu ba,eline down to O.44lbfmmRtu_ Source: GE-EER Experience 1;sl2/1/02_ (Also see low-dust Sell installatiun list for pulverized coal boilers)

Minnknla**Pow~r** Coop."'tiv€,Inc. A2-2J Dums & McDo"ncilNOK BACT Analy:;i, Study APPENDIX 112 U.S. NOK en"I'O] ll.elrufilProjects



### LOWNUx BURNRRS (R"pl""nm",t ornrodijicatiOllSj """lid "'/0 OVERFIlll':AIR COmilllll!U Puh'erizetl cll1tl-fired boiler.' Dynegy M,clwesl Generation (formerly Illinois Power) ]'u]yen7.ed Coal, wall-fired lIavana Slnl,on, Unil6**1~78 vint;,~c**  460 MW B&W boiler, bil"m;nou, lIIinoi.' coal C,E-EER provided modiIications 10 lhe original il&W**dual·r~glS\cT** burners, and a" OFA 3yslem in 1000. Vendor claJJned [uliload NOx was uncbanged [wm 0.38 lb/mmFllu baselinc. Souroc; 

### GE-EER Expe, iencc lis12/1/02. (AI,o see low-du:>l SClt ;nstallaIlOLlliSI [or pulvem.ed coal boilers) Dynegy**Mi<1w~sl** GeneratJOn (limnedy JIlinul' l'owe,) Pulvcrizcxl Coal, Taugenlially-i1red**V~nnjl1ion** Slalion, Uml I 1955 vinlage 81 MW CE bolier, h,luminolls Illinois co,,1 'I'his rowling oppose<l**fir~** uir (Mobolcc USA ROFA) syslem wa, imlallcrl in July 1001, ns pari ora "Rowlni," SNC"R 

### +ItOI'A sy'le"" wilhoul low-N(lx bu",e,s. Mubulcc 2004 tecnnical paper**~bimed** 10 lower full h'd NO" by 62% from 0.58 Ib/mmBlu hu,dine lu O.l1lh/mmBllI lU July 1001 (w,lhoul r.NB Or SNCR). (")**Suure~:** en) Moborec 2004 !Cehmc,,1 p;lp<.T. (Abo .".., SNel\. installalion SUrrlrm'nes [or pu]veri""d**,,,~,I** hoilers). Georgia POW'-T Pulvem.ed tu"l, opposedwall-firecl, Harke Branch Unil 1 250 MW B&W buib, 1965 vinlage 2003 "lm1up "arlee B,--unch Unill J59 MW Rlley boiler, 1%7 vinl"ge 1998 ,Iartur' B&W provided 24 DRB-4Z low NO" burners [or Unit I B&W bOiler,**2~** DllB-XCI. luw NOx bumers for 1111il 2 Riley bOll" (bel,eve**,ulJlk~,,1** "oasl**ligoil~** is primary [lIel)_**Som~e;** B&W's**e~pcTicu"e** I;s!. No NO" reduolion claims. Kam;a" Clty Power & Lighl Pulverized eoul, opposed wall-tire,], 600 MW B&W i1uilor fhWlhom Unit 5 30 !lUmers, 200 I**v,ntag~,** (powder It,vel' na'in "ual) B&W provided 

### JO DRB--'1Z low NO"**burn~rs** mulll OFA ports wilh**lh~** new bOller. $Olll'CC; 

### B&W's e"perleoce IJSL No NO, reduclion c1oims. New England Power Company(NEPCO) Snlcm Harbor Sialion Pulverized Coal, IronIwall-fired, Unils 1,2 & 

### 3 1952, 1952,1958 vinlage (eo.\lcTIl bit. coal) 84 1\1\"'0" 2, & 156 MWe B&W boiler> tNt!> slartup In 1995, 1995, "nd 1993 Kiley claimed Unit 

### 1LNB, reduced NOx em;,,;olls by 57% frombusc!ine o[ 

### L10 IhlmmBlu dmvn co 0.42 IhlmrnBlu; Unill'3 I.Nlh .chicvcd 42% NO" 'educli"n from a ha.,eliTle "r·O,95 Ih/mmBlu <luwn 10 0.55 IbJrnmR\IJ; UniI3'., LNlls Jchiev",1 60% NO" reduclion [rom a baselJlle or ].05 IblmmBtLl ,Iown 10 0.42Ib/mmBlu. Source: Riley Power (Babcock Power Inc.) 

### 8116104 experiencc Ii,!. (Alsu ,cc SNCIl ;tl31.1I'lion ,"mmarics [or pulvcrizeu eoal boiler,).
Northeml UlilillC' ([orme,ly Poblic Scrv;"c ofNew Ilnmpsl,irc) Sh,lkr Slal,on Pulverized 

### CooIJI16 Fuel oil, fronl_wall_fired**lJnit.'~,** 

### 5, &6 1952, 1955, 1957 v;olage 50 MWe x 

### 3 Fosler Wheelcr hoilers RJlVl provided (6) l."w NO, bunK, modiJlcaliuns pCT boller in 1994, ]992, &**199~** 10,p"cl;vcly; LNIls**rcdll~cxl** NO"**~3%** Jrom 0.85 10 0.48, 50% lrom 1.0 10 0.50, Jnd 51% [rom 0.82 10**O,~O** Ib/mm[J(u. Souree: RJM**expcrien~c** lisl 

### ·,il

llum' & McJJolloell 112_22APPENDIXA2 u.s. NOxComrolRetrofitT'rojocts NO"BACTAoaly,i, Study



### LOWNO, BURNERS (Replacement ar

### maJijicaritJI1.') wialldwI" OVERFIREAIR Ctlntinued Pulverizod ooal-fired boilers Potomac Electric Power (formerly Wesl Pennsylvania Power) ChalkPoinl Station Pulverized Coal opposed wall_fired Units 

### I & 2 1964, 

### 1965 vintage cnslern biluminous eoa] 360 MW (nomin"l) B&W boilers DB Riley (now Babcook Power) CCV lype low NO" burners relrofilted in ]993 and 1994, respectively. Vendor claimed to 10WlT NO" up 10 52% and 50% from 1.35 and 1.40 lh/mmBtll b"sdin", (10 0.65 and 0_70 IblmrnBlu, assumed al full load). Source: Riley Power (Babcock Power Inc_) 8/16104 experience Iisl. (Also see Convenlional Gas Rcburn installation summaries for rulverized coal boilers). Xeel En"rgy (formerly Puhlic Service CompJny ofColorado) Cherokee Unit 3 Pulverized coal, wall_fired, B&W boiler, 16 hurners, 1962 vint"g" 175 

### MW October 1992 ba,din" testing sta,1ed (weslem bituminous coal) Installed (16) Fosler Whccl"r Conlrolled Flow/Split Flame lo'v NO, replacemenl burners 

### "s part ofa DOE Ckun C.oal Technology gas reburn dC"TIlOnslraliilll perrormed with Gas Rcsearch Inslitute 1992- 1995_ Unconlrolled NO" 

### wi original B&W flare-type burners w"s 0.73 lh/mm81u. RJ.:plueemcm J.NBs (as.-,uming OFA included) reduccu NO

### x 37% 10 O_461hlmmBlu125J• Source: (lj) DOE NETL 200 I Technical paper.

-0; ----,---- 

### A.2,2 

### -------;ycchiiic;,:-i{ileraillre References for U,S. NOx Con-lroi"Rctrofil Projecls:-
II) SNCR While Puper, lnSlilutc ofClean Air Companies,lnc. (ICAC), SNCR Committee, May 2000, Fuel Tech wellSlle ttilI);llwww.fucltcehnv_eomfpdrffPP,534,R<;If i»RE12001 Technical Parer "Design anu Demonstration ofRich Reagent Injections (RRI) Performance For-NO" Redu"lion at Connectiv's BoL. England Slation'· by Murc A_ Cremer und Bradley R_ Adams, Reaclion Engineering Inlernalional, David 

### C- O'Connor, E1eclric Power Research Inslltule, Venkalu Bhamiuiputi, Conectiv 

### R.I._ England St"l;on, onu R. Gifford Broderick.IUM Corporalion, presenled al lhe 2001 US EI'NDOEJEPRI MEGA Symposium on SCR and SNCRs, Chicago,ll., Augusl 20-2), 2001_ 

### (REI wcb,ile hllp:f/www_reaclion--eng.comidonwloJu,./rri mega_pdQ
I') REl2002 Technical Paper"Demonslralion ofRi"h Rcugentlnjection for NOll Control in AmerenUE's Sioux Unit]" by Marc A. Cremer and Bradley R. Adams, Reuctiilll Engineering lmemaliilllal, Duvid E_ Boll, AmcrcnUE, and David C. O'Connor, Eleclrie Power Research Instilulc, presenled at lhe US DOE Conference on SCRlSNCR for NOll**Conlro~** Pitlshurgh, PA. May 15-16, 2002; and

REI 2003 Technical 

### Paper "Improved Rich Reagent Injl:Clion (RRl) Performance ForNO" Conlrolln Coal fired Utllily Boilers" byMarc A_ Cremer aTId Huafeng D_ Wang, Reaction Engineering IntemationJI, David E. Boll, AmerenUE, Edmund Schindler, 

### RJM Corporalion. anu Edmundo**V~sque7~** RMT, Inc., Alliunl Energy C0f]l_, prcscntc<l al2003 U.S. 

### DOE Conference on SCR ami SNCR for NO" Control,**Pi~sburgh,** PA, Oclober 29-30, 2003.

(1) REI 2004 Techni,",l 

### psper, "Eva!uJlion ofCost EffecliveNon-SCR Oplions for NO" Conlrol in PRIl Fircd Cyclone Roilers" hy Marc A. Cremcr und David H. Wang, and Bmdky R. Adams, Reaction Engineering Inlemalio""l. David E- Boll and KeoneLh B. Stuckmeyer, AmercnUE, pre.,enloo allhc Western Fuel" Sympo,ium, 19'1> Jnlemalional Conference on Lignile, Brown, and Subbiluminou:; Coals (formerly Low_Rank fuel<), Oclober 12-14, 2004, Billings, MY.

MlIlnkOLa Power COOI,crdlivc, Inc. A2-V [Iums It McDonnelli'lOx BACT Analysis SI"dy

----- APPENDlXA2 U.S. NOx Control Retrofil ProjeolS



### : REI 2005 Tcchnical 

### P"P<-T "NOx /:;missiom Below 0.15 

### IblMhtu**Aehic~cd** ill a Cyc1one""irerl BoikT U,ing: In-Furnace Conlrol" by M. Cremer, B. Adnms, nnd A Chiodo, Reaolion /:;ngineering Inlernational; C. Gie,maon, 

### K. Stuckmoyer, and J. Boyle, AmercnU/:;, presenled at Ihe Po",erGen Internalionnl 2005 conferenee, December 6-8, 2005, Las VCl}lS, Ncvada.

(5)DOE-NETL 2004Tcchnicall'aper "Rcbummg Projects in the Deparlment ofEnergy's Clenn Co"l Technology Demon.'lr"lion Program", by Al Mann nnd Tom Ruppel, Parsons Corporation, and Tom Smkus, National EncrgyTechmcal Laboratory, presenled al the 2004 DOE-NET!. Cnnt"renee 

### on Rebllrning lor NOx Conlrol, Morg,mlown, "WV, M"y 18, 2004. A reburn-related doculllenl (an "l'daleu vcr"ion ofu posler ffOmlhe May 18 Conferenoe) i.' Iitled**"Sco,-~ennJ** On Reburning 6/1/200-4" by Al Mann and Tom Ruppel, P"Thons Cmpomlion, "vailubk on-line ai,**hllp:!lwww.ncll.doe.go-".!QllbIJcaIione!m:q{<;.e_d.i.ngs/041NOx/posLe~lRcb"rnlng%20Scon:omd.pdf**
(.j GE bJergy**200~** Technical paper "Reburn Technology**Apl'lie~ljon** Gui,ldincs", by David Moyeda, GE Energy, I'reoenleJ "Ilhe 2004 DOE-NETL Conference on lleburning tor NOx Control", Morgantown, WV, May 18, 200-4.

1'1 B&W 2004 Technical Paper '-Il&W's RebUlning Experie"ee", hy H.**F~Uflll,** G. Maringo, A. Yagiela, A_ Kokkino" Babcock & Wilcox, ("0., prc,enlcu allhe 200-4 DOE-NETL Confel'ence OLl Reburning [or NOx Control, Morgantown, WV, May IH, 2004. (TIlis dal' is;l duplic"lc of;, more uet"iled technical paper publi,hed enrlicr, "B&W's A,h-"noe On Cyclone NOx Control Via Fuel and Air Siaging Tcchnologies", by II. ",,,zan, G. Mnringo, D.W. Johnson, and D.W. Won!" B"beock & WIlcox, Coo, 

### c.T. Beard, r""-\Iman Ko<l"k Company, and S.E. Brcwsler, Tennessee Valley AUlhOl'ity, presenled at Ih,' El'IUDOE-.El'A Comhincd Ulilily Air PolhJlanl Conlrol Symposium, Allanla, GA, Augusr 16-20, 1999)_
CO)H&W case hislory "B&W Cyclone Reborn Le",ls 10 NOx RcdllCliol1, Wiseonsin Power & Lighl Co. Neboll Dcwey Unit No. T' (from website hllp:l/www.bahcock_com/pggip.•le".\ehislorie•.hlml••laled 1997). r') DO/:; Topical RerorI Numl:>er 14 "Rebunling Technologlcs for Ihe Control OfNilrogen OxiJe, Emi.'sions from Coal-Fired Hoilers", conducled under ""ramIe cool'eml've agreemonts l:>el",een Ihe U.S. Dep'lftmcnt ofEnergy, lhe Bahcock & Wilcox Compnny, lin""l:}' .ml EnvlTonnlC"Ill"1 Rcsearch CorpOfalJon, and New York Sial,· Elcelrie & Gas Corpomllon, May 1999_ {LOJTechLlical Pap"" "PreJi"llUns ofFLGR al Commonweallh EdIson's JolieI Unil6" by NGB Tcdnologics, posted on lhell' ",ehsile: hltp:!lwww."{(blech wm/subp"l!cs/proj/joliot ccsul1'!.hlllll (111 REI 200 

### I Technical paper ··CFD Eval"alion ofFnel Lean Co" Rcbunl (F1.GR"') ,md Seleclive NonCalalytic Rcdu"tion in Owensboro MlInic,pal UlillI;es' Elmer .sm,lh StaI10n", hy David 

### H. Wong, Marc A. Cr"mcr, and Dradley R_ Adom" Reaclion Engineering Inlcrnation"l, K.D. Frizzell, Owen,bol'O Municlpallllihlies, "nJ G.c. Dlisalko, S"rg"nl & Lundy, 2001 US EPAIDOE MEGA Symposium on SCR "nJ SNClls, Chicago, II., Augu.<l 20-n, 200 1_ I"IUS EPA Dockcl OAR-2002-0076-0446 1l"Chnical .support DoclimeLll lor nART**NO~** Limits for Electric Genemtmg Units Execl Srread.,heel 61 1512005, postcu on Iheir web,ile: hit 1,:1/ <Io"kcl.,=va,gov/c.dJellU**hI~!>I** E I)

### KS**l~** fIl1ffi1De**I~** i

### I**\~ ~w"**  obiecII

### d' 090007d4 8084562b (IJ)Burns & McDonnell inlen"l dniahase.

Bum, "'- MeDonuell A2_24 Millnk"lli l'"weT ('oope,a!,ve, IlleAPPENDlXA2 u.s. NOx**Co~trol** Retrofil Project> NOxDACfAnalysis Study

(1') Technical paper ''Operaling Experience and Future Challenges With SCR Applicalions", by Gerd**Beckrnan~** and ClaylonA. Erickson, Babooek Borsig Power, Inc., presentcd at Power-Gen Inlernalional 2000, November 14, 2000, Orlando, FL
IJ<) DOE NEIL Technical**P"P~T** "Control ofNilmgen Oxide Emi",ions: SelcCllve Calalytio Reduction (SCRl", Clean Coal TeehnologyTopical Rcpon Number 9, July 

### 1997, posled on lhcir websile:**hl:ip:IIWl'(W.ne~.doe,gov/Dublicalions/OlhersilopicalsilopicaJ9.pdfs.** (") SCR White Paper, lu.titute ofCleau Air**Comp~nies,** Inc. (ICAC), SCR Corruniuee, November 

### 1997,**http://www.m~moni"DrocomiAmmonia%20LibraryINOx%20Redl.clionfInslilmeo/020ol../o20** CJcan%20Air"/o20Co SCE Pllf, linkcuto R-M. Technologies web,ile http://www.rrmeoh.nellartieals.hLm
117)Technical paper**·'C'-lI.rdi~al** Unil I L"rge Scale Seleclive Non-Calalytic Reduclion DemonSlrulion Projecl", by l'alrick M. Malone, American Electric Power Service Corp, 

### "ml 

### Dr. William IL Sun, Fuel**T~"Ch,** pre:;cnLed at !he ICAC Forum 2000, M"rch 23-24, 2000, Ros,yln, VA. 118ICP&I, 2001 Technical Paper ··Rolaliug Opposcd fire Air (ROfA) and SNCR·', by Mark Shilling and Gary Tonamakcr, C"rolinn**Pow~r** & ljght Co

.. presented allhe 2002 DOE-NETL**Co~ference** on Uabwned C"rbon On U,ility I'ly,,-,h, May 14, 2002" Piltsburgh, PA. ('''Mobotec 2003 Technical Paper '·lnjc<:lion ofUr"" through the Rolamix System to ObLain Improvcd NOli:**Reduc~ou·.,** by John Ral'lou ;Illd Edwin lladdad. Mobotec USA. 

### Inc.,**pres~"TIlcd** at lhe 2003 U.S. DOE 'Conf.:rence'

## on SCRand SNCRTofNO;;:**Conlrol~PiUsbiirgli,** PA, OcLoher 29-30.-2003;- (2O)RE11999 Technical Paper "CI'D Modeling ofSNCR Pcrformance in**Conec~v's** Indian RivcrUnils 3 and 4", by M. 

### Creme, "nd M. Heap, Reaction Engineering Inlernalion"l, M. Zoccola, Conecliv. and V.**Ci"rl~nl~,** Hamon-Research C'-OltrelJ, pre""ntcd nl DOE Conference 0" SCR and SNCR for NO", Conlrol, May i0:-21, 1999, Pillsburgh, PA. (llJMobotec 2004**T~"Chnical** Puper "SCR Levels ofNOx Reduction wilh ROFA and Rolamix (SNCR) at Dynegy's Vermillion Power Slalion··, byKriSlopber A. Coombs, Sr., Dynegy Midwest Gencmlion, and Jay S. Crilley, M"rk Shilling, and Edwin Haddad. Mobolec USA, Inc., presClllCd alLhe 2004 Slack Emi

.. ,ions Sympo.,ium, Clearwaler Beach, FL, July 18-30, 2004. 

### Ill) MiLsui Babcock2003 Technical pnpcr, "NOxSlar"" Plant Demonstration, Oclober 2003", by 

### K-W. Moms and G. Hesselman, Milsni Babcock (US). presentcd nllhc 2003 U.S. DOE Conference on SCR and SNCR for NOx Conlrol,l>iltsburgh, PA, October 29-30, 1003.
(2]) MilSul Babcock 2004 Technical paper, "InslalJ'lliOll ofNO"S"'r"" SysLem atTVA Colbert", by Keilh W. Morris, Milsui B"bcock (US), presenled althe Coal-Gen 2004 Confercnce, July 28_30, 2004, Ovcrlrmd Pnrk, KS.

(2') GE Energy (formerly GE-EER) 1004 Technical paper ··Experience wilh Rebwn forN01< Emis.,ions Control", by Don Engelhardl, Roy Payne, David Moycua, Blair Folsom, GE Energy, presenled at the 1004 DOE-NETL Conference on Rcbuming [orNOx Control, Morgantown, 

### WV, May 

### 18, 1004.

(5) DOE NElL**Tecbnic~l** pnpcr "Evalualion ofG<!, Rcburning and Low-NOx Bu",er. on a Wall-Fired BOller A DOE ARSe.<smenl", dated February 100 I. oor,JNETL-2001/114J, posled on thcir websilc: hLtr:llwww.neLI.doe..£!lv/cctclresouree&'pdf.<!eercolGRLNBPPADdr.**Min~kola** Power**Coopcrdliv~,lnc.** /\2·25 Barns & McDonnellNOx BACTAnalysis Snody APPENDlXA2 U.S. NO, Conrral**Rolrn~ll'cojecl'** I") GE**En~r&y** (formerly GE-EER) 2004 TeclmieaJ paper**·'Powerpl~nl** mosaics: paving the way 10 0.11 IbfMMBlu without .sCR", by HI.iT Folsom, GE Energy, published in lhe March 2004 issue ol"Modom Power Systems.

(17) NGB Technical ral,er '"["'uel**L~an** Gao Reburn (l'l.GR'''') Technology [or Achieving NOx Emis.,ion,**Complianc~:** Application 10 a Tangentially-Fired Boiler", hy RlChanJ 

### D. Frederiksen, WlTIln J.A. Dahm, and Grelar Tryggvason, NGB**Te~hnQIQgics,** Inc., Bernard 1'. Dreen, Roge, GJickerl, and Jo.,eph A. Urich, Eneqw Systcm> Asso<oiates, Jnd Jolm 

### M. Pralapns and Robe'l 

### V. Semuskas, Gas J{eseacch Instilule (GIU), presented al Ihc 1998 Joinl Arncrie,nlhpanose Flame Rcse.,-ch Commiltce**InlemutioTJ~J** Sympo,ulm J;;!1yLronmemal Conlrol ofC-OmhuSlioil Processe" I.nnovative TechnologyThwards ,he 21 <, C,,-nl.ury, Maui, Hawuii, OOlobl, II 15, 1998. "')2001 Tcc1mical PUp'T "Applie,li,," ofFueJ Lean (jas RehurTl Wilh 

### SNC"R On i\ 198 MW Coal-Fired UIlIily Boiler" by David Kille", Carolina Pnwer & Llghl Co., Jobn M_ lJoyle and John JL 0 'l.eJry, Fuel Tech Inc.,**pr~s~nlcd** al thc 20UI US EI'NDOEfEI'Rt MEC,A .syrnposium on SCR ami SNC"R" ChIcago, II.., August 20-23, 200I. t"ITcchnieal paper ·'Fir" Commercialln.,tallation ofAmine Enhanced Fuel Lean Gas Rehum On Uml>; I and 2 at Puhlic Service Electric & 

### Gas Mercer Slalion", by A",lrew 

### F_ Gomez, Publie Servic,- I:;leclric & 

### Ga, Company (I'SE&G) Mercer GeLleralirlll Sliltion, Akxunrler S. Damon·and John 

### IL O'l.eary, Fuel Tech, Inc., and Robcrl Seh,eec<lgosl, Enl,gy Systems AssociaLes, presenled at Ihe 2000 DOE-NIoTL Conference on SCR and SNCR ror**NO~** Conlrol, Pillsburgh, PA, May 17-18,2000

.


# .. .

Ilurn> & McTJunnell A2-26 Mmnk"l.., PowerCoop0,"IIV<, 111c.

### APPENDlXB EERCREPORT Ash Impacts on SCR Catalyst Performance

# ASH IMPACTS ON SCRCATALYST PERFORMANCE

PrOf'll"""by: Sleven A- Ben,on, PhD.**Enor~y** & Environmenlal**Reseat~h** Center Univor:sily ofNorthDakota PO**Do~** 9018 GnmdForks, ND 58202-90Ig

OClober 2005



# ,

# , :-;

### TABLE OF CONTENTS

LIST OFFIGURES 11 LIST OFTABl,ES , 111 EXECUTIVE SUl\1MARY ES-J INTRODUCTION 3 INORGANIC COMI'OSITION OFLOW-RANKCOALS ..4 

### INORGANIC TRANSFORMATIONS AND ASH FORMATION 5 ASH DEPOSITION ON HEAT-TRANSFER AND OTHER SURFACES EXPOSED TO ASH AND FLUE GAS 6 ASH-RELATED EXPERIENCES AT MRY 1,'AClLlTy 7

Ilislory 0 rFu**cn~ce** SIoggingiFuullng

_ ••,.,.,.,•.•.•.•.•..•.•.•...•.•.•.•.•.•.•.•.•

__•.•.•.•.•.••.•••••••**,~.,** ._.•.•..•.•..•.

_.•....•.•.

__ 9 Advanced Boiler Pec(onnance J"dices •.

_ .•.•

_ _._ ,••_,••••,.,.,.,.._ .•.•..•.•..•.•..

_.•

_.•.•. ., 9 

### ASH-RELATED IMPACTS ON SCR CATALYST_PERFORMANCL 16 Full-Scalc Slipstream Testing

__._ _ _ _. .. .. 16 SCRAsh Dep<Jsil Characlcrizalion.............

.. .. 19 SCR Dern'il Fommlion Mcchilnisms

_ _ " 20 Low-Tempcrnturc**pyru,~lr"",s** _ _. 31 

### Conclusion: SCRIs Not feasible FOR NOx MDUCTION at M. .-. young 34 REFERENCES 36I.lST OF FIGURES Figu,e L Variohili'y orseleoled oonSlimen\s in core anolysi' dOloba,e providc<! hy FIN! Coal, L1u_ "nd Minnkola cool dOlo!>a,e _.. .. .. .. J 

### Figure 2_ Overall processes ofa,h deposilion Iypical ofa lignile- or .,ubbiluminolls-lired hoiitr

.._ . ...__.. 0 Figure 

### J. 

### T"o frequency dislribution for all Coal Qualily Management System (CQMS) dala, of -. .. 

### 12 Figure**~.** cI '" lilslIlbnlion lor Hi\ ,cam co"I

.... Figure 5. T", dislliblllioJJ for HB 'cam c(]ol "

.. Flgurc 6_ T"o dislrib"uol1 for KC ,cum coal

.. . 13

'" 13

. .... 11 

### Figure 

### 7. Varimions in the delivered coal qualily during a lesl 

### bUlll period

... 

### _14 Figure 

### 8. Weight ehm,ges ror PRB-blelld**co~1** 

### ash exposed lo flue gases and ammOllia 

### at Ihree lempemluIe'

_ 

### 21 Figure 

### 9. Weight change' for PRE-blend conI ash exposed 

### 10 fllie gases and ammonia wilh and without 

### SCR CJtAlysl present
.. _ 

### 22 Figllr<' 10_ CmalJ!" pLessurc dmp"1 B"ldwin**~IJljon** JI 0 10 2 months of0l'eratlOn -. 22**::~**

Figll,e 11_ Caluly,tpre"uTo rlmp at Coycle S"t[OI1 a\ 0 I" 2 monlh, of**~per,,';on** ... 

# n fig,,,e I L C",uly_'l p",_""re drop "I**C~JuJjlloio** S,"IHlIl a\ 0 10 2 monLhs**~fopcr"li",,** __


### Fignre 

### 13_ Piclures 

### of**cal~lysl** 

### inlet nlier about 

### 2 months o[lesling 

### at eacb planl figun:; 

### 14_ Piclure, 

### ofcalalyst inlet aller aboul 

### 4 monl118 

### ofexposure 

### 10 flue 

### gas JIld parlicu]ale

__ ... _ _ . ...... "

...... 2.1



### ......24

.. 25 -- ."

Figure 15. ScM ;rrulgC' (][ ash collecLeo on ca'"l)"1 surf"cc al Ihc Boldwin Sialion allor (, mOJllhs**~[exposuro** ......... ".

. ..''''''

... 26
Foenre 16. SLM imigcs "I',,-,h colkolod on eolillyS! 'ur["cc allho COYOle S,,'I;ul1 

### anor4 mOlllhs of**~xp""lLrc** ......... Figure 17_ Compari'oll ofcl1lr.il1cu a,h ano deposlied "sh OIl Gllalysl for Columbia Slal;on

__ 

# '"

Figuro 13. Mec],Jni,m u[SCR eololysrblindillg "i.**Ih~** [mIl1ali"n "r "MOles ""u coroo"ales (mudllicd alkT Pritchard alld oLhers (30)) -'

_ ] 1



# "L1STQFTABU:S 

### Table 1_ Characteristics and Indices Calculated for Selected Center Lignite Samples Table L 

### Advanced Index Values for Other Coals (12)



# '" 13 IJj; 

### .",. 'C'_ ASH IMPACTS ON SCR CATALYST l'ERFORMANCF.


### EXECUTIVE SUMMARY The**~sh** 

### deposition behavior ofthe ligniles from North Dakotais the most complex ano severe ofany coals in the world, and insl<lllation ofcatalysts for NO, reduction is going to be plagued with problems. The Center lignite fired at the Milton 

### R. Young (MRY) Power Station is highly variable in abundance ofvarious types ofash/slag-fonning components. Ash-foming componenL. consist ofinorganic elements (sodium, magnesium, calcium, and potassium) associated with oxygeo functional in the organic'matrix and mineral grains (quartz, clays, carbonates, sulfates, and sulfides). Upon combustion, the inorganic components undergo chemical and physical transformations thal produce inteJlllediate inorganic species in the form of ,'norganic gases, liquids, and solids. The alkali and alkaline-earth elements combine with minerals during combustion, resulting in low-melling-point phases that cause a wide range of fireside deposition problems. In addition, the alkali and albline-earth elements also fonn very small particles that are camed into the backpasses 0 fthc combustion system amI react with flue gas to form sulfates that can cause deposition, blinding, and plugging problems in selectivc catalytic reduction (SCR) sySlems. This report analyzes these problems, aod concludes that SCR is not a feasihle option to control NOx emissions at MRY Power Station because ofthe high sodium levels present in the coal. Following is a list of the key problems that arc associated with Cenler lignite which have not been overcome amI, in our opinion, make the installation of SCR at the MRY plant technically infeasible forNO, controL

}> 

### Blinding**ofCat~lyst Por~s**  

### by High Sodium Compounds X High levels ofalkali and alkaline-earth elements present in lhe coal fired althe MRY plant prodl1ce small particles that react to form sulfates that blind the calalystpores. The high levels ofsodium in the coals combined with calcium will produce lowme!ling"point eutectic sulfate compounds that will form and mell inside the pores ofthe catalyst.

• Alkali and alkaline earth sulfates are enhanced by cyclone fired system. The cyclone firing resulls 

### in partitioning ofthe ash between botlam slag and the body ofthe boiler. The sulfate fonning materials are more concentrated in the ash as a a resuH ofcyclone firing.

• Sulfate fOJlllalion is enhanced by lhe presence ofan SCR catalyst; this accelerates the sulfation reactions, causing blinding ofthe catalyst The sulfate reactions nrc more severe atMRY because oflhe high temperature where an SCR would be installed. The higher temperalurc increases the ratc offonnation of**sulfate.~** 

### and rate ofpore plugging. The testing conducted by the Germans found catalyst deactivation and blinding occurs when firing coals with lignite Orbrown coals thot have ashes that are rich in alkali ano alkaline-earth elements

..

### The findings hy Ihe Germans Were confirmed by reccnl SCR catalyst slipslream lesling that .howed significanl evidence of**~odium** 

### and calcium-rich sulfate forrnaliun lhat fill amI plug the eatalysl al both Egoite- and subbituminous-coal-fired power planK The resuhs**of[hi~** 

### recent tcsting showed Ihallllc pre.,ence ofsodium si.[,'nificanlly CIlhanced Ihe fOITnalion ofbonding 0 fparLicies and mOre rapid suH:llion, filling ofpore.", and rapid inneaHe in pressure drop across the eaLalysL

• DeposiL carryover, or ··popcorn >L,IJ," plllgging lhe top ofLbc SCR calalyst is n signif,canl problem because ofthe eXlremdy bigh deposilion rales o[lhe Cenlercoal. \Vhen [iring Centercoal, deposits fOITlI 'On various parts ofLhe boilerretl"iring conLinuous soolblowing_ The soolblowing ofupstream heal-exchange e'luipmenL will cause deposit Irngmel1ls Lo be carrioo back to lhe SCR enlalysL, resuHing ill plugging. In addition, during soolblowing 0fthe SCR eatalySI, Ihe enlrainJllenl ofdeposit fra!'.Jllellls along wilh 1 be soolblowing media will rt,"lllL in signiJicanl erosion ofthe catalyst slIrfaees.

• Reeemle,ting with subbilllminous**~nd** 

### lignilic coals**indic~lcd** 

### a signifieanlly higher level orpore filling nnd plugging in the**c~lalysL** 

### exposed to lignile asll as compare [0 sllbbilllminous coal ash_ Tbe**cal~[ysl** 

### pores as well as thc catalySI surface 1Il the lignile lesls were complclely coaled wilh a sodillm calcium sulfate**m"leri~l,** 

### while only pore Jilling was fOllnd in Lhe subbiluminous co"llesling. The pressure drop aCross Ihe calalysl exhibited for lignite was 4 Lo 5 limes**gre~tcr** 

### Ihun 111"lloll",1 Ii,r a ci1lalysl exposed to snbbituminous coal a-,h_ The plugging "ccllned OVCr a 1000 hOllr tcsl period.

:r 

### Cold Side SCR Installation High-sodium lignile**co~l** 

### from the CenterMine Hagel A and B**s~am** 

### coal produces signifkant le"elH 0fhomogcncollHly condenscd sodilim suifale Ihal pass Lhrough Ihc ESP mul weI sembbcr_ Thesc small particles have**b~en** 

### shown to pass tbrough " wet scruhber and will accumulnle 00 surfaces oflail-end SCR systcms_ The accumulaled materials require sootbJowing 10 remove thc particul"le and will resull in inclcased "pacily

.

•Liquid**pyrosulf~** 

### tc materials at lemperalure, as low as 5J5"F Ji-"m sodium HlIlfate materials Oeeun; in coal·flrcd power syslems and is well documcnled_ Pyrosulfate.s will fonn and emlse blinding oflail-eml SCR dcvices_ In addilion, SCR**syst~ms** 

### arc knoWJl to**c~tilJyZC** 

### lhe.**fonn~lion** 

### of

### SO) from 

### Sal.**Th~** 

### presence ofSO, significantly enhanccs the [ornmtion "flhe pyrosullales_ _'c

### ASH IMPACTS ON SCRCATALYST PERFORMANCE INTRODUCTION Ash produced during combustion ofcoal in conventional powersystems is a major problem that results in decreased ellicicncy, nnscheduled ontages, equipment failures, and increascd cleaning_The many ways in whieh!hc detrimental effects ofash manifestthemselvcs in a boiler system include fireside ash deposition on heat-transfer surfaces, corrosion and erosion ofboilerparts, poor slag flow, and production offine particulates that arc dimwit to collect. Decades ofresearch have been conducted to develop a bellerunderstanding ofilie chemical and physical processes ofash fommtion and deposition in combustion systems_ Overviews ofashrelated issues and compilations ofworkby many investigators can be found by referring to the work o[Mehta and Benson (I), Schobert (2), Baxter and DeSoliar (3), Couch (4), Williamson and Wigley (5), Benson and others (6), Benson (7), Brycrs and Vorres (8), Raask (9, 10), and Benson (II). This work has led to a detailed underslanding ofash formation and behaviorin combustion syslems as well as the development ofpredictive methods (12, 13). The chemical composition and physical characteristics ofash-fomling orinorganic components (mineral and organically associaled elements) oflbe fnel(s) fired have an innoence on tbe following processes 

### in the combustion sySlems:

Transformalions ofcoal inorgnnie components to ash particulate and vapor-phase species Boilerdesign charaCleriSlics, including number ofbumers, radiant section area, lube bank spacing, access for cleaning, and number ofsootblowers 

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• Ash transporlto heat-lransfer surfaces in utility boilers

• Erosion wear and Slicking

• Ash deposil growth and impact on he"tlransfer

• Ash blinding and plugging ofselective catalytic reduction (SCR) catalysIs

• Ash deposit removability The ash deposition in North Dakotalignite-fired powerplanls is a major problem that impacts all fireside surfaces oflhe powerplanL The ash problcms arc due to the variable and complex nature oIinorganic componenls associated with lignile coals (2). Upon combustion, the inorganic compon...**nL~** 

### undergo chemical and physicallransfonnations lhal produce intermediate inorganic species in lhe foun ofinorganic ga.<!<>;, liquids, and solids_ During the gas-cooling processes in the boiler,**~le** 

### gas-phase species condense and the liquid-phase materials solidify. The abundance ofthesc gas-phase and liquid malerials enlrained in the bulk gas now is highly dependent upon coal composition and system operating conditions. Thc inorganic materials are lmnsported to heat-transfer and calalyst surfaces hy diffusion, electrophoresis, lhermophoresis,

### and inertial impaction. The particle sticking and accumulation rutes are dependent upon the quantity ofash and the abundance ;md viscosity ofthe liquid-phase components. In hightemperature regions ofthe boiler, high·temperature sodium-caleium-aluminosilieate liquid phases aeL as the sticky material, causing deposit initiation, growth, and dcvelopmcnt ofdeposit slrength. As the temperalUTe ofthe nue ga"es decreases, the comlen,alioTl and reaclion ofnamevolalilized species playa more significant role in the fomlation ofdeposits from lignite coals. The f"llllaLion ofsodium and/or calcium nmgnesium sulf..ltes dominates the deposit acculllulaLion mechanisms at lower temperatures. The aluminosiIicate phases are dominant above aboHt j 

### SOOOF. Below ahout 1R(JO°F, the ,u]fale pha,es heCtlllle ,table, with an oplimum LemperaLure offomlation ofabout 1400"1', and can foml at temperaLmes as low as 300°F. The most significant problems that prohibit the successful operation ofSCR

### catalysis 10 [igniLe coal is the formation oflow-tempcrahlre sodillm-calcium-magllesiuJIl suIJnles and phosphates that will limn on the surfaces ofcatalysts and the carryover of**dcptl~ilS** 

### thm will plug the catalYSI openings, resulting in inereased preSSUfC drop and dccreased erIiciency ( 14--1 6).



### INORGANIC COMPOSITION OF LOW-RANK COALS Inorganic elements in coal occur as tliscrc!e minerals, organically associated calions, and cations dissolved In pore waler. TIle Ii-aelion 0 r inorganic components thal are organically associated varies wilh coal mnk. Lower-ranked suhhitulllimllls amI**1i~'1lillc** 

### coals have high levcls ofoxYflen, which acl**a~** 

### h<lmling**~ites** 

### [or calions such**a~** 

### sodium, magnesium. calciulll, pola"ium, strontium, and balium (Olher minor and trace e!emenls may also be prcsenl in lhis form). In higheHanked coals, bitllminolls and anlhracite, inorganic components consist malnly ,,[minerals. Miner'll grains are uoually the most abundant inorganic eomponenL in coal. The major mineral groups found in COols include silieatcs, aluminosilicates, carbonaLes, ,,<I 

### fide;, "ulfales, phosphates, and some oxides. The behavior ofash produccd during coal combnslion is rclaled to the abundance, size, and associalion ofmilleral grains in the coal. In addition, tbe association ofthc minerdl grain wilh the coal malrix innuences the temperature and gascous environmcnl the mineral is exposed to during combustion. A mineral associated wilh the organic parI ofa coal particle i, said to be included. A mineral that is nol a5sociaLed with orgaoic malerial is referred lo as excluded. The behavior of Lhe orgallically assoeiatcd elemcnts, Lhosc demenlS thaL arc alomically dispersed in the coal matrix, must also be measured as to thcir ahundilllce in the coal. The organically associated elements will read ami interad with the other ash-fomling conslltuents during eomhuslion. The CenLer lignile is highly variable in abundance ofvarious types of**a~h1s1ag-[tllllling** 

### conslituenls. Ash·Ionning components in the Center lignitc are of1\\'0 typcs. The liml [onn may cOllstitutc lip to SO% 0fthE a,h and is derived from inorganic elelllenLs (sodium, magnesium, ca1cinm, and potassium) associaled wiLh oxygen fllnclional in the organic matrix 0[lhe coal. The second lype consists ofmineral grains (sand, clay, limestone, and pyrite). The minerdl, are discrete partides ofash-forming spccies <tud the sources ofsilicon, aluminum, iron, lilanium, and minor amollnts uflhe ca1cinm and ptlla,sium. The Cenlerlignile fired aL the MilLon 

### R. Young (MRY) planL has been examined extensively**bec~lIse** 

### ofits problem with ash behavior. Analyses

### ofas-fired and drill core samples have been conducted. The mean and the range ofselected components are shown in Figure 1. The resulls indicate that botb tbe abundance ofash and the abundance ofmajor oxides in the asb vary significantly. In addition, the abundance ofalkali and alkalIne-earth elements (Na and Cal varied dramalically. Variations in Si were found to be the most significant. High levels orCa "nMorNa were found for lower-ash coals as compared to high levels ofAI and Si .ssociatedwith bigher-ash coals (17, 18)_

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# " , , , , , I**~,** 

# -**~.** 00**~.** 

# "". ,,",0- 

# .,. Slo,· 

# - ........ '" 

# -

....base 

# - """,base 

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# ._. -- """",,,,,,

Figure 1. Variability ofash and selcctcd constituents in core analysis database providedby BNI CoaJ;'Ltd_ and Minnkota as fircd coal analysis database.

The variability ofthe asb-forming componcnts has been examined for the approximately 5000 'aInples characterized to date_ Wide variations in ash contenl.s and the major asb-forming constituents are observed_ During the mining processes, the inorganic components are mixed, and some ofthe extreme chardcter!slic, are diluted (17).

INORGANIC TRANSFORMATIONS AND ASH FORMATION 

### Thc inorganic coal components undergo complex cbemical and physicaltransrormations during combllStion 10 produce intermediale ash specics. 'The inorganic**~lIecie:;** 

### consist ofvapors, liquids, and solids_ The partitioning ofthe inorganic components during combustiou to form ash intennediates depends upon tbe association and chemical characleristics ofthe inorganic components, the physical characteristics ofthc coal particles, tbe phy,ical chanlCleristics oflhe coal minerals, and the combustion conditions_ The physicaltransfonuation orinorganic constitucnts depends on the inorganic composi[ion ofthe coal and comhu,tion conditions_ The inorganic components cnn consist of organically associated cations, mineri11 grains thai are included in coal particles, and exeluded mineral grains. There is a widc range ofcombinations ofmineral-mineral, mineml---cual,



# ,

### mineml--calion--coal, and mincrul--mincral--cation -coal associalions in coaL These a'Socialions are uni'lue 10 each coal sample.
Thc**~hysical** 

### lransfnmmtions involved in 

### Ily ,,-,h formation include 

### I) coalescence of individual mineral**~ins** 

### within n char pnrticIe, 2) shedding oflhc ash particles from thc surface ofIhe chars, 

### J) incomplclc coalcscence l!ue 10 disinlegration oflht: char, 4) 

### conveclive transpOlt ofash from Ihe char**surfa~~** 

### l!uring**l!~volatiliznlion,** 

### 5) fragmenlation of**lh~** 

### inorganic mineral particles, 

### 6) formnlion {)

### L**c~nospheres,** 

### and 

### 7) vaporiznlion and subse'luenl comlensatiOJl ofIhe**inorg~nie eompon~nt"**  

### llPOn gas cooling. As a resull oflhese inleraclions, the ash**h~s** 

### a bimodal size dislrihution. The Sllbmicron componenl i, largely a reSlllt ofthe**condellS~tion** 

### of**flam~­** 

### volalili:t.t:d inorganic componenls. The mass mean diameter ofthe lnrger pnrtielc, is approximately 

### 12 to 

### 15 ).1m, depending upon**lh~** 

### coal 

### imd combuslion condilions. The larger-size parlicles have been called Ihc residual ash by**~0111e inve5tig~tor'**  

### (19) hccau,c lhe,e ",h particles resemhle, to a limited dcgret:, the <>riginal minerals in lhc coaL Pmce",,-, such a, ash mineral coalescence. pm1ial coak,cence, a,h shedding, and char liW,'TI1enlatinn during char eombuslion and mineral fragmenlalion, all play an important role in lhc size and composilion ofIhe final 

### Ily a,h. I 

### ,0ehdeJl and olhclO (20) 

### and 7.ygarlicke and othcrs (21) 

### indicale lnal lhree potenlinl mOlles for 

### fly ash generalion can be u,el! 10 describe fly nsh particle-size and composilion evolulion. The first, '"fine limil," assumes that each minernl grain fonm a fly**~sh** 

### particle and Ihallhe organically associaled e1emenls form fly ash parlicles ofJess than 

### 2 ).1m. The second, "Iolal eoalcsccnce," assumes one fly ash particle forms per coal panicle. TIle lhird, "parti,jj coalescence," 'ill

### ggests**th~t** 

### the 11y**~Sll** 

### eomposiIioil 000 

### particle size cvolvc bceau",e 

### of portial coalescence. The translonnalion, ofexcluded minerals nrc 

### dependenl upon Ihe physical characlerislic., ofthe mineral. Exclul!ed minerals such as (juartz (SiO,) can be canied lhrough Ihe combustion syslem wilh its angular slruclure still intact. Excluded clay minerals can frag.ment during dehydratioIl, mell, anu fonn cenospheres. The hehuvior 0

# rexcluded pyrite depends upon jls morphology. Some oflhe pyrile may be prescnl as fulmboids. Frnmboidnl pyrite may fragmenl more casily limn ma."ive pyrite particles. In addi [ion, the decomposition ofpyrite is very exothermic, and illmnsfomls 10 pyrrllOtile and 

### oxidizes 10 

### FeO, l'eJO., and 

### Fe,O.ll!ming eombustion_



### ASH DF:POSJTION ON HEAT-TRANSFER AND OTHER SURFACF.S EXPOSED TO ASH AND FLUE GAS The characleriSlies ofa deposit dcpcnl! upon lhe chemical and physical characleriSlics of lhc inlem,,,diale ",h species, geomelry ofIhe syslem (gas How paUems), ga, lemp=tllrc, gas composition, and gas velucily. Figure 2 illuslrates lhe a,h deposilion phenomena inutilily boilers. Ash purticle accumulalions occllrvia tramport**ofp~rticles** 

### [0 lhe {ireside surfaces (heat lransler, ceramic materinls, support malerials, SCR catalysts, bnghouse materials, and ESP wire, and plale.,) and Slicking ofthe particleS. The lransport mechanisms imporlant for ash depo,ilion include**sm~[J-particic** 

### mechanisms for particles less lhall 10 

### 1'm Ihal involve Iherlllophoresis, electrophorcsis, and vapor-phase and smaH-partic1e di [fusion; and large-particle mechanisms 1"r particles greater lhan 10 ItIII that involve incrtial impaclion. The abiElY oflarger particles lO ,tick l!epcmls upon lhe quanlity and viseosily oflhe liquid phnse on the parlicle 'llrface.

### Thermophoresis is aphenomenon Lhat involves the transport ofvery small parLicles as a result of"- Lhermal gradienL from hoL gases Lo cooler surfaces. Electrophoresis is lhe transport of pnrticJes**beeaIl.~e** 

### ofa difference in charge. Vapor-phase and small-particle difTusion occurs in the boundary layernext to the surface and results in lransport ofash to the surface. lnerLial impaction is a larger-parLicle phenomenon wbere Lhe particles are ofa sufficient size and density to leave airflow patLerns around the Lube and impinge upon the surface ofa Lube or deposit. Deposits thal form in high-temperature regions ofthe boiler, such as Lhe radianL secLion, are called slag deposits. Deposits Lhat form in lower-Lemperature regions ofthe boiler, such 

### as in the convective pass on steam tubes nnd lower-temperature surfaces snch as SCR eaLalysls, arc called fouling deposils. Slag deposits 

### arc usually associaLed with a high level ofliquid-phase componenLs and are exposed to radialion from the flame. This is a description Lbat many researchers usc Lo aid in classification ofdeposits since some engineers call any Lype ofdeposil "slag". Slag deposiLs arc LypicaJly dominated 

### by silicate liquid phases, but may also contain modcrale to high levels ofreduced iron phases such as FeO and PeS. The liquid characteristics of the**sj1ie~les** 

### are highly dependent upon the quantities ofNa, Mg, Ca, K, 

### and Fe ash on the silicates. 

### In mIdilion, the in.itiating layers ofslag deposils may consisL ofvery fine particulate and can produce a rellectivc ash layer. This phenomenon is especially evident when high organically associaLed calcium subbiLuminous coal is fired. These coals produce small CaO particles lhat usually form lhe initiating layers.

--, Fouling deposits form in the lower-Lemperature regions ofthe boilers and, in most cases, do·notconmin the- high-levels of-liquid phases thaL are usually assoeiaLed wiLh slaggiug-tJ1lc deposils. Fouling deposits contain lowerlevels ofliquid phases rul 

### compared to 

### slag deposiLs. The fouling deposil liquid phases usually consistmainly ofsulfaLes that bind Lhe particles Logether. Fouling deposits typically fOlTIl as a resull ofthe reaction ofgas-phase sulfur oxide specIes with panicles rich in alkali and 

### alkaliue-earth elemenLs.



### ASH-RELATED EXPERlENCES AT MRY 

### FACIJ,TTY The MRY is a minemomb elecLrical generating plant located near Cenler, North Dakota. The slalion consisLs oftwo uniLs: Unill, rated aL276 MWg, began production in 1970; Unit 2, rated al 506 MWg, began prodnction in 1977. Both UniLs I and 2 are equipped wilh B&W cyClone-fired boilers; the Unit 1 boilerhas seven cyclones, and Lhe Unit 2 boilerhas twelve cyclones. Annual sLaLion gross generaLion is approximately 5_5 mjJJion MWh. BNl Coal Ltd. is Lhe sole coal supplier for Lhe MRY Station. Coal is mined from Lhe nearby CenLcr mine, which consists oflhrec disLincl seams varying from 

### 2Y,-9 feet thick. Coal is snipmined using two draglines and is loaded with fronl-end loaders and delivered Lo the planL with bollom-dump haultrncks. Annual coal producLion is 4.3 million tons peryear.



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# '''- Hislory ofFurnace SlaggingIFouling Prior 10 1991, be8ides annual maintenance outages,load reductions and forced oUlages due to furnace slagging/fouling were the largesl**caus~** 

### ofproduelion loss_ In 1985, opending guidelines were established thatreduced furnace slaggingifouEng, including deslagging outages scheduled every six months. In 1991, a 3-molllh hoiler cleaning cycle was propnsed llnd initiated. The goal oflhis program was 10 increase annual generation by running lhe unils al higher suslained loads and scheduling boiler"cleaning outages at 3-monlh intervals_ However,**fumac~** 

### slagginglfouling continued to have nsignificant impacl on plant operations. Success was mea,moo in the number ofproduction days botween**boiler-c1~aning** 

### outages. During the mid-1990s, a major outnge every third yearwas scheduled for each unit. In 

### addition, Unil 1 c1enning 0I1tages were scheduled for SD-90-day runs (four cleaning oUlages per year), and Unit 2 

### cleaning outages were scheduled for 65-75-day runS (five cleaning outages per year). The problem was that furnace amI convection-pass surfaces graduaIly become coated with ash deposils, which, overtime, sootblowers cannol remove. Some ofllle contributors to the ash deposils were as rollows:

• Organically associated sodium is a primary contributorto deposition problems. Sodium is vaporized in the cyclones and condenses on other ash particles, causing them lo**becom~** 

### slicky and deposit atlhe furnace exit. lbe problem is associated with sulJale fornlation and occurs in the convective pass, including the economizer.**Sampl~s** 

### show that sodium in the ash varies from 0.60/.-13.0%. Organically assoeialed calcium is another component that causes deposition problems. Unlike sodium, calcium does nol prodnee a vapor-pha,e component. Calcium does react willi silicate (derived rrom clays) to cause low-melling-point phases thaI produce wall deposits and deposiLs in the high-lemperature regions ofthe conveelive PiISS_ Calcium also prod'ices very small particles that will be transported 10 heal-transfer surfaces, resulting in the fonnation oflhin, light-colored layers caned reflective ash. These small particles ofash arc carried through to the back passes where lhey are sulfaled and can combine wilh sodium to cause the formation ofslrong\y bonded suIrate-based deposits_ Samples show that calcium in lhe ash varies from 6.80/.- 24.0%.

• Clay minerals and quanz - Centerlignite can contain higb levels ofillite, which has a 1:3 AJ;Si ralio and high levels ofpotassium, both ofwhich cause wall slagging and high-temperalure fouJing_ Quartz and otllCr clays can significanlly conlribule to the mass ofthe deposilS. Samples show thaI ash contenl varies from 5_00/.-25.5%. Advanced Boiler Performance Indices Advanced indices are useuto relate Ihe coal characteristics as determined by computercontrolled scanning eleelron microscopy (CCSEM) and chemical fractionation 10 ash behaviorin a coal-fired ulility boiler (12). rUel perfonnance is estimated in lenns ofslag [Jow behavior, 

# ,

### ahm,ion and erosion weHr, wnll**~Iagging,** 

### high-Lemperalure**.,ilicale-ha~cd** 

### convective pass fouling, and low-temperature suifate-hased convective pass fOlding. The following indices are llSOO 10**asses~** 

### the effects 0 

### fash behavior on \ILilily boilerperfommnee:

• Convective-Pass Fouling indic",," Suiration lndex: Indicales Ihe pl'Opensily ofdeposil lO form in Lhe eonveeIive pass of/he ulilily boilerin the lemperature range Ii-om 1000Q

### -I 750°F

_This index is**ba~ed** 

### On lhe availahility ofalknli (Na and K) and alkaline-earth (Ca and Mg) e1emenL' to reacl wilh SO, and SO) 10 

### limn sulIHles. The sulfales ore the primary materials that cause pmticle-Ioparticle bonding in high-calcium coals. The su [[hies arc thcnnodynamically sLable at lemperalures below abOUI1650°1'.lndex vallics range from I (low) 10 lU (severe). Silieo**~e** 

### 111dex: Jndieoles the propensity ofdeposi**l~** 

### to rorrn frum 1600" ·2400°F. This index is related 10 Ihe fonnation ofdepusilS in which lhe sihcale malL'Tial**i~** 

### the primary componenlllwi bonds Ihe deposits togelher_ The informalion**u~ed** 

### to derive the index inehldes Ihe size ofthe**minel'~ls** 

### sLleh as qunrtz and clay minerals, availability "falkali**~nd ~lkalille-eaJ1h**  

### elemenls,**~nd** 

### viscosity u rthe silicale liquid pha8e. Imlex values rallge from I (low) to 200 (seYcre). Walerwall Slagging Siagging Tndex: Indicates lhe propensily ofa deposit to foml on the radianl walls fwrn 2000° 3000°F. The b""i8 0 fthe slagging index is Ihe size oflhe minerals (espceially lhe illile, qllal1z, and pYJite),**a8soei~lioll** 

### ofIhe calcium (calcile can contribule to slagging), ".\1([ 

### viscosity oflhe silieale-based liqllid plmse. Index**v~lue"** 

### range Ji-om I (low) Lo 20 (severe)

.

• Wenr Indices Abrasion IOdq: This index indicates the potenlial for wear offilel preparalion and handling equipment. The ,,,,aris relaled 10 

### Lhe hardness ofminerals in the coal. The primary minerals of**eOn~em** 

### include quartz and pyrile. 111e index**v~lues** 

### range fi'om 0.1 (low) to 10 (severe). Erosion lmiex: Thi.'> index indicates thc polentjal for wear ofhuilerparts due to Ihe impnetion offly ash pat1icles. The**ew~ion** 

### jndex**i~** 

### dependem upon Ihe**~ize** 

### oflhe ash}mi\leral particle, size ofthe pm1icle, and velocity nflhe parlicle_ The index values range from 0_] (low) 10 1.0 (severc). Cyclone Slagging Index: This index provides informalion on Ihe slag now behavinr in cyelones_ The fnelors lhal are included in Ihis index include the pnrtilioning oflhe ash in Ihe**~yelone** 

### based On size and assoeialion oflhe ash-forming componenls in Ihc coal. The partiLioning onhe ash belween Ihe slag and entmined ash can 8ignificantly inf1uenee the now heha"ior ofthe sing. Slnndard partitioning ctileria have been developed lO provide the composilion onhe**~Iag_** 

### The composilion is used to estimate lbe**visco~ity** 

### "flhe slag**~s** 

### a function oftempemture. The index vahles hnve severnl ranges as r"l!nws: 1 (low**vig~o"it** 

### y). T .5-2.5 (oplimllm viscosity), >3.0 (sing frce/.ing).

# ~.

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### • Slrength Developmenl Index: 1be slrenglh index is based on the ability oflhe deposited material 10 develop slrenglh_ Strength development is primarily dependent upon lhe abundance and viscosity orthe liquid"phase componenls in the deposits_ Index values jess than 0_25 indicate thai the material will produce weak deposiu;; index vahles of 0.25-0.34 indicate weak-lo-modernte-strength deposils; index values of0.34-0.41 indicale high-strenglh deposits; and index values >0.41 indicale flowing slag_ Indices were calculaled for arange ofcoals from lhe Centermine, and the propensity for ash deposilion in various portions ofthe boilerindicates wide variations, as shown in Table 1. 

### The BNI numbers indicale the location in the seams where lhe coal originaled: Kinneman Creek se;,m (KC), Hagel A (HA), and Hagel (HB). Each seam has a differenl distributioll ofminerals and organically associated clemenls IhaL can have a significanl impact on lhe fOnJlation nf deposits in lhe systcm_ Compnrisoll ofCenlerlignite to subhilUminous and biluminous co<lls from otberregions ofthe United States, shown in Table 2, indicales significant differences in the polcllualto fOnJl dcposiLs in the boilers_ In all cases, the lignite (not lhe wors/. coal from CenLer mine) from tbe Cenlermine has a high propensily to produce deposils as compared 10 the other coals. AnoLherindIcation oflhe variability oflignites can be illusLratedbased on the calculation ofLhe lemperalure where the slag flow would occur. This is defined as lhe T250 lcmperature, where the slag viscosIly is 250 poise. Frequency dislributions ofLhe T250 values for a1l1he data for coals analyzed are Illuslrated in Figure 3. Calculations ofT250 values for 1212 samples obLaine'dTrom the Cenlermine database (17) were made using empirical relalions derived from CCSEM aud chemical fraclionation data and knowledge ofhow ash partitions in lhe cyclone_ Figure 3 shows a bimodal dislribution in the T250**b,,-~ed** 

### on lhe Urbain equalion calculations_ The primary mode was at a value 0[2000°1'. The secondmy mode was at abOUI 2700°1'. The results indicale lhal many oflhe coals have a sufficiently low T2S0 

### for good slag now. However, coals with T250 al 2700°F arc not. suitable for maintaining good slag flow. Figures 4 lhrough 6 ilIuslrate the variaLions in T250 for the various SeamS ofcoals characlerized. The HA and HB seam coals appear 10have large numbers ofsamples, wilh 1'250 values at or near 2000°1'. The KC scam coal, as illuslraled in Figure 6, has extremely high T250 values. Based on Lhese data, the KC coals are not favored relative La Lbe slag flow behavior oflhe ash. Frequeuey distrIbutions ofcyclone slagging index values indicaLed significantvariations in slagging poleutials ofcoals mined from the lhree seams, KC, HA, and HB. This infonnaLion proved particularly useful in planning Lbe mining and firing ofcoal from the KC seam_ During a July 1999 testbum, lhe composilion oflhe cores was used 10 examine and iJluslratc lhe variabilily ofthe delivered coal qualily based on base-to-acid ratio calculated from the asb composition. FIgure 7 shows lhc variation in Lhe base-lo-acid"ratio and the seam where the coal was loaded_ The base-la-acidrdtios were calculated from core di1ta Lbat corresponded to the location in lhe seam where lhe coal was mined. There is a signifieaut variaLion in !hebase_ lo-acid ratio for the coals. The coals lhat have lhe highest base-to-acid ralio are Lypically from Lbe HA seam_ HB scam coals generally have an imermediate base-to-acid ralio. KC ortop-seam coal has the lowestbase-lo-acid ratio_ Lowerbase-to-aeid-ratio coals lypically produce slag wiLh high viscosilies.


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### Table 

### 2. Advanced 

### Indo Values for Other Coals 

### (12)

AdV'lIlted lndices Cyclone Slogging Index ConveClive ross Fouling Silica,e S"l[ale Wall Slagging Index Erosion Index Ab

..,iun Index Lignite NOrtilDakota

61.8 4,09 

# '2. 0.15

0.71 Powdor River Basin 

# " 23.99 2.88 '-85 0.17 1.96 Bilumino,", Illinois

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## o '-53 0.14 3.94 Bituminous Appalachian 

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# " 1.66 0.17 1.96



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### for all.Coal Quality M"ll"gcmelll 

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### diSlrihution 

### ror HA seam CO'll.



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### --T'50-distribution-for KC-seam coal--

Figure 7. 

### Variations in the delivered coal quality during 1I tesl bumperiod.

### Figure 7 shows the sequence ofdeliveries beginning on July 6 ami ending on July 12, 2004_ During (his period, (he mf\jorily orthe coal delivered wos fmm lhe llA scam, roll"wed hy KC, and 

### liB. Mosl ofthe deliveries allemate<i belween KC nnd HA- Figure 6 shows several**iJl~t~nccs** 

### where sigllifiennl qunnlilies ofKC coal were delivered, on J

### lily 6 through] lily 9" The lJunntily ofKe coal delivered 

### will have the polcnlial to increase the viscosily ofthe ",lag 

### and re.sull in poor slag now from the cyclones.

ASH-RELATED IMPACTS ON SCR CATALYST I'ERFORJ'dANCE Ash-rclnled impncls on SCR**ealaly~l** 

### per[omlallCe will depend upon the composition ofLhe coal, the lype offiring syslems, nue ga, lemperalure, and ealnlysl design (14-IG, 22) Thc problcms cllrrenlly being**experien~ed** 

### "n SCR catalyslS**includ~** 

### the J"Il"Willg: Formalion ofsuifale- and phosphate-based blinding malerial, on lhe sUJ'fnec of**calaly"~ls.** 

### Carrying**ordep()~il** 

### fragments, orpopcorn ash, from olherpa,ts oIlhe boiler amI del""iling on lop 0 

### rthe SCR**c~t~lysls.** 

### J.icata and Olhers (14) conducled tesls on a Soulh**Afric~n** 

### and German Ruhr coal and found**Ih~llhe** 

### Gelman Ruhr coal signilieanlly increascd the prcssure drop**n~ro""** 

### the catalysl beCallSC ofthe accumulation ofash_ They roumllhalthe German coal produced highly adhesive ash consisting ofalkali (K and Nn) suIfales. In mldilion, lhey reportcd thal Ihe alkali clemcnls are in water-solublc form and highly mobile and will migrate lhruughoutlhe ci1lalyst malerial, reducing**~etive** 

### siles. The water-,oluble fonn is typical 0 

### rorganically associated alkali clements in coals. The German Ruhr Valley coal**h~s** 

### abolll 9.5% ash ,md 0.9 % S on an as**re~cived** 

### hasis, and**lh~** 

### ash consisls mainly o[Si (J8.9%), Al (23_2%), Fe (l 

### \.6%), and ea (9.7%), with lower levels ofK (1-85%) and Na (0.85%) (l5). Cichanosicz and Muzio (1G) summarized the experience in Japan and**Germ~ny** 

### and indicaled lhal the alkali clements (K 

### and Na) reduced the acidity o[lhe catalyst silcs lor lolal alkali conlenl (K+Na+Ca+Mg) of80/0-15% oflhe asll in European powerplants. They also lonnd (hal**~lkaJine-earth** 

### clements such as**c~lcium re~ct**  

### wilh SO) on lhe**cal~lyst,** 

### ","ulLing in plugging ofpores and a decrease in the ability ofNil) lo bond to**c~telysl** 

### sites. The levels of**~aleium** 

### in the**co~ls** 

### thm catL'oo blinding ranged from J%-5%ofthe ash. The mechanisms for lhis lype oflow-lempemlUJ'c deposilion have been examined and mo<ieled in delail allhe Energy & 

### Environrnenlal**Re:;e~rcb** 

### Center (EERC) in work tenned Projecl S"dium and Projeel Calcium in lhe early 199Us; however, the focus oflh"se projects WeS specific 10 prim'lfy superhealer and economizcrrcgions ofboilers and nol SCR syslems (22, 23)_ DepositbuildllP ofIhis lype can cITcclivelyblind orma,k the calal**y~l,** 

### diminishing ils n:"activily for convening N02 10 N2 and wnlcr and potenlially crealing increased ammonia slip (14)_ Arsenic and**phosph~les,** 

### which arc nol Uncommtln in low-rilllk coals, may also piny arole in ealalysl degencralion. Arsenic 

## is a known**c~laI** 

### ysl poison (14) in "pplicalions such as**c~lalylic** 

### <lXi,bli"n rorpollutioll control.l'hosph"tes**c~n** 

### occur in**low-temper~lurc** 

### ash dep"sils 10 crealc blinding dTecls, and lhcy also OCcur with arsenie and**e~n** 

### cnusc**c~talysl** 

### poisoning (2J).

### Lignite and suhbituminous coals produce ash iliat plugs and blinds catalysts (25-28)_ Thc problems currently experienced with SCR catalysts includc the formation ofsulfate- amI phosphate-based hlinding materials on the surface ofcatalysts and the carrying ofdeposit fragments, orpopcorn ash, from other parts oftbe boiler and depositing them 00 top oftbe SCR catalysts (14). The most significant problem that limits lhe successful application ofSCR catalysts to lignitc coal is the formation onow-temperature sodium--ealcium-magnesium sulfates, phosphates, and possibly carhonates thal wlll fonn on Lhc surfaces ofcatalysts and the**caTT)'o~er** 

### ofdeposits that will plug the catalyst openings, resulting in increase<.! pressure urop and decreased efficiency (14-16, 27-28). The degree oflbe ash_related impacts on SCR catalyst performance depends upon the composition ofthe coal, lbe type offiring systems, flue gas temperatnre, and catalyst design (15--16, 24, 27-28)_
In studies (7) the impacts oftempernture and the presence ofcatalyst on the ability ofash to sulfate were examined_ Thc tests were conducted using a thermogravimetric analyzer (TGA). TGA testing was conducted nsing a<5-flm-si2.c fmction ofash produced from Powder River Basin (PRS) coals and lignites aml exposing them to vapor-phase sulfur dioxide with and without catalyst at several temperatures_ The aim ofthe testing was to determine lhe potential of lhe formation ofSUlfates to cause particle-tn-pariiele bonding thnt leads to the formMion of deposits in the tempernture range where SCR catalysts are useu_ The TGA testing is focused on dctcnnining the reactivity ofthe**<5~j.1m-asb** 

### produced-from selected PRB-anu blends to sulfur tIioxidc and gas-phasephosphorus species as a function ofiemperature. Testing was conducted
--,,- to determine the weight gnin with flue gas containing >lmmonia. The impact temperature on the

...., weighL gain due to the fonnation ofsulfates for a PRS blend is shown in Figure 8. The rates of sulfalion were found to 

### increase with'increased temperature_ The results show ml increase in the weight gains when ammonia nnd phosphorus were added_ Ground cali\lyst wns mixed with PRB and placed io Lhe TGA. Increases in-weight gain were obsei-ved when catalyst was added as COlnpared to haseline ca.es for 100% PRB, as shown in Figures 8 and 9, respectively. The presence ofcatalyst enhances the formation ofsulfates.
Full-Scale SlipstreamTesting More recently (8), the behavior ofash and mercury in flue gas produced from tbe C<1mbustion oflignite and subbituminolls coals from the United Slates ofAmericain selective catalytic reduction (SCR) sysLems for niuogen oxide**remo~al** 

### has been examined. Typically, these coals contain ash-fonning components that consist ofinorganic elements (sodium, magnesium, calcium, and potassium) associated with the organic matrix and mineral grains (qulll1z, c1>lys, carbonates, sulfates, and sulfides)_ Upon combustion, these coals produce ash that has an abundance ofalkali and alkaline-eartb-ricb oJ(ide particles 

### (<5 j.1m) that are carried inlo the backpasses ofihe combustion system and react with nue gas to fonn sulfates and possibly carbonates. The fonns ofmercury in the flue gas produced from the lignite and subbituminous coals arc dominated by the elemental form_ Slipstream testing was condueled at two subbituminous-fircd powerplants and one lignite-fired powerplant to determine the impacts of ash on SCR plugging, hlinding, and mercuryoxidalion_

### The SCR**sJipslre~m** 

### syslem consists ofLwo primary componcnls: the conlrol room and the SCRreactor. The reactor section consists ofa calalysl seclion, an ammonia**iJ~cclion** 

### system, and sampling poris [or 

### NO. nt 

### lhe inlcland exiL oflhe eatnlysl section. The conlrol room houses a eompuler syslem thallogs daln and eonlrols lhe gas now rates, lemperalures, preSSlire {Irap 

### ncross the calalysl, and soolh [owing (.ydes. The eompuleri8 programmed 

### 10 maiulain cO\lslanl temperature ofthe calalyst, go,s flow**J~tes,** 

### soolblowing cycles, and ammonia injeclion. The eompoler is equipped wilh a modem lhal allows for downloading ordala and modificalion orlhe operalion ofthe reactor from a remote computer localed at lhc 

### EERC.
Flue gas is isokineticaJIy exlraclcd from the convective pas, ofthe boiler upstream oflhe air healcr. The lemperaturc is**typic~lIy** 

### nboul 

### 790Q

### F_ Thc nue g"ses pa,s lhrough "4-inch pipc equipped wilh sampling, thermocouple, and pressure ports. Ammonia is injected into lhe piping upslreillTl oflbe rcador section. Thc reaclor con,;,ls ofa slcel housing thilt is approximately 

### 8_5 inches squure and g 

### fcctloJlg. The reactor seclion has lhrec eomponenls, including allow slraighlener, a pulse seclion Or soolblower, amI a ealalysl lesl section. A 

### metal honeycomb is u8ed il5 u 

### 110w slraighlenerupslrcam ofthe eatulysl seclion and is about (j 

### inches long_ A 

### purge seclion was inslalled ahead ofthe cUlalysl lesl seelion 10

### remOVe**aecumul~ted** 

### dusl nnd depo.,il,_ The calalysl lest ,ection is localed downslream oflhe purge seclion. The entire ealnlysl seclion i, insulaled and equipped wilh strip healers for lemperilture conlrol. The ealalysllesl Seclion is 

### 3.28 

### ft (l 

### m)**i~** 

### length und houses lhree catalyst sections. Thermocouple and pressure laps are loealcd in the purge seclions for measuremenls before and after each scelion_ Thc induced-drafi fan is used 

### 10 cxtract approximately 

### 400 acfm 

### (200 scfin) offlue gas from lhe conveelive pass oHhe utilily boiler lo achieve an approach velocily of

### 5.2 

### mls (17.0 fVs). The gas vcloeily is similar 

### 10 that found in full-scale**applic~ljons.** 

### The lolal gas 110w through the**rca~lorreprescllts** 

### a lhcrmulload ofapproximntely 

### 300 kW. The rallge 0 

### f 

### opentt;ng**~omlilions** 

### for Lhe reactor is lisled below:


### X Gas**lemper~lUJ'e: -700o-800~F**  

### X**G~s** 

### now rale: 

### 400 500 adin X Approach vdocily range: 

### 5.0-5.5 m/sec X Ammonia injeclion rale: 

### 0-5: I with NO, level X Tempering air for fan:

- 

### 50-200 selin X Calaly,t dP: 

### 0.5-1.0 inches waler columll X Fan sized for up 10 

### 30 inches watcr column The calalyst inSlalled allhe Baldwin and Coyote Stations**wa.~** 

### lhe HaldorTopsoe catalyst. Topsoc's DNX-seJies ofcalalysls compriscs SCR DENOX c"lalysls lailored to suil a comprehensive rangc ofproccss requiremenls. DNX-sene, eatnlysts are based on a corrugated, fiber-reinforced tilanium dioxide (TiO,) carrierimpregnated wilh lhe aelive componenls vanadium penloxide (V,a,) and ltmgsten lrioxide (WO)). The calalysl is shaped to a**mo~olithic** 

### slruclure willi a large number of parallel channels. The unique talalysl design pmvides" highly porous slruclure wilh a large surface**~rea ~nd**  

### llIl ensuing large number ofaclive sites. The pitd, ofLhe calaly,t**W>l~** 

### approximalely (j 

### mm.

# ,. , 

### Thc calalysl inslalled:lt lhc Columbia Station was a BabcockHitachi plale-type calalyst. This calalyst is aTiOl-based plate calalyst., developed and manufaclurcd byHilachi- The pilch of the catalysl was approximately 10mm. Thc coals produced ash lhat had significanl accUllllJ1alions ofash on the catalyst On both macroscopic and microscopic levels. On a macroscopic level, there were significant observable accumulations lhal plugged the enlrance as well as lhe exit ofthe calalyst sections. On a microscopic level, the ash materials filled**pore.~** 

### in the eatalysl and, in many cases, complelely masked the porcs within 4 monlhs ofoperalion. The deposils on the surfaces and within the pores ofthc calalystconsisled ofmainly alkali aml alkaline-earth clemcnt-rich phases lhal have been sulfaled. The resuHs ofthis testing found lhat the <5-fIm ash rich in alkali and alkaline·earth elements is captured on the surface and wilhin the calalystporcs_ These materials react with SOllSO, in the flue gas, 

### resulLing in the formation ofa continuous phase lhatblinds lhe ealalyst. The ability ofelemental mereuryto be oxidized across the SCR calalysl was investigated al a North Dakota lignile-fired plant. Thesc resulls showed nO oxidation ofmercury across lhe SCR calalyst. The reactorwas inslalled at the Baldwio Stalion and operated for a 6-monlh lime period On thc HaldorTopsoe catalyst. The information obtained from tesling included pressure drop,

_.• sootblowing cYcles, and reactor lemperatures_ Figure 10 show "the pressurc drop across the calalysllestperiods from 0 10 2 monlhs. During the lirsl two monlhs ofoperation, the pressure 

### <- was aboul 0.5 inches ofwater; at the end oflwo monlhs, lhc pressure <irop was about 0.8 inches ofwaler, indicaling plugging had occurred_ The air was pulsed a minimum ofevery 8 hours in an altempllo maiutain deanliness_ The reactor was monitored on a daily basis, and adjuslments in pulsing cyclcs wer" made in order 10 minimize deposit accumulation. However, for the firsl two months, the pressure drop slendily inereased. There are several periods where the uuil was laken off-line; during lhose limes, the temperalure oflhe calalysl was maiutained. Al 2-monlh inlervals, nsection ofcalalysl was removed and replaced with a new one. ForMonths 2 through 4, the pressure drop was hIghly variable inilJally bUl was aboul 0.8 inches ofwater. From Monlhs 4 through 6, the pressure drop was maintained belween 0_6 aud 0.8 inches ofwater. This is due to the installation ofa fresh calalysl scelion and leaving two thirds oftbe catalysts in place that were partially plugged. The gas 

### veloeily in the single section ofnew, clean calalysl was high because ofchanneling, and the resuH ofthe high gas flow was less deposilion and accumulation. Gas vcloeily has a significanl impact on the polenlial for deposits to form. However, at high gas velocity, low NO, conversion Is likely. The reaclorwas inslalled allhe Columbia Station and operaled for a 6-month period of lime wilh lhe BabcockHilachi catalyst. The information oblained from the tesling included pressure drop informalion, sootblowing cycles, and reactor lemperalure. Figure I1 shows the lesl periods from 0to 2 months. 1be pressure drop aeross the SCR upon installationwas aboul 0.4 inches ofwalcr and increased 10 an average ofabout 0.5 inches ofwater, butranged from less than 0.4 to greater lhan 0.8 inches ofwater. The pressure drop for Months 2 to 4 increased from about 0_5 to 0.7 inches ofwaterbecause ofaceumulalion ofash. After cleaning the rcactor and replacing one catalyst seclion, the pressure drop was aboul 0.3 but increased to over



# "

### 0.6 inch,,-, "fwaler up 10 aboul4100 hours. There**wa~** 

### an outage a11he plant, and aggressive pulsing oftile reactorW,LS conducled; lhe pressure drop was broughl hack down 10 0_3 but rapidly increased 10 over 0.5 inches ofwaterwithin 500 hours. The**~ame** 

### reaclor lhal was inslalkll allhe Baldwin Station w,,-, moved and**in~lalled** 

### al the Coyole Sialion. In ,1{IJilion, the same H,lIdorTopsoe catalysllype wos used in lhe reoctor. The reaelor was operated for a (i-monlh period oftime. I'igure 12 shows Ihe test periods from 0 10 2 monlhs. As Ihis paperis being prepared, Ihe reactor is slill operating on-site. The pressure drop aLTOSS the**calaly~t** 

### upon installation**wa~** 

### aboul 0.4 inches ofwaler. Afl"r only 750 hours, the pressure drop wa_, 1_5 inche", "fwaler, indicating significanl pliJgging ;lnd hlinding. Very aggressive air pulsing was conducted, wilh lillle success in removing Ihe deposils. The pressure drop for Ihe calalysl was over lwo limes grealer thanlhe pressure drop observed for the Baldwin Station utilizing Ihe same reactor end same calalysl. Al aboul1700 hllllrs, the reaClOr w"-, cleaned, and a seclion ofealalyst was removed lor characlcrizalion. The prcssure drop afler clcaning was about 0.8 10 1.0 inches ofwatcr. TIle**pres~ure** 

### drop did n01 incrcasc as rapidly bccause ofthe higher velocities Ihrough lhc clean section oflhc calalyst_ The lOpS ofIhc catalysIs wcrc**pho(ograph~d** 

### during inspecliun and sampling oflhe catalysl sections. Figure 13 shows Ihc ash materials thai accumul"led on lhe**calaly~t** 

### inICI 

# "n.", 2 monlhs ofoperalion_ Thc mOSI significanl accllmulalion was nOled for the Coyole Slalion, followed by Columhia aml Raillwiu. The Coyole Slali"" had some largerpieces of,,-,h deposil**m~terial** 

### On lhe surIace**a~** 

### well "-, plugging 0f 

### the**~atalysl** 

### passages. The Baldwin**St~lioll** 

### showed some ohvious deposilion along the walls ofthe reactor and some accumulalion on the inlel sections. The Columbia Station showed more significanl accumulation and**~lngging** 

### limn Ihe Baldwin Slation. Aftcr 4 months, Ihe lops ofthe calalysls were pholographcd durIng inspection and sampling ofIhc catalyst scclions, as shown in Figure 14_The mosl significanl accumulation was "oled for Ihe Coyole Station and somc accumulation for Ihe Baldwin Stalion_ 

## sel{ Ash Deposit Ch3rade,·jzalion 

### The characleristics ofthe ash**materi~Js** 

### thaI eollceled on Ihe calalysl surf..1ccs and pores were characlerized by SEM and x-ray microanalysis and, in selecled cases, XRJ) was used 10 detcrmine Ihe cryslalline phases present. The catalysts were sampled afier 2, 4, and 6 monlhs_ ·nlC scclions were sampled, and approximalely 2.5-cm squares wcre mounled for SEM analysis on double-slick lapc and in cpoxy resin. The double-stick lape**"ample~** 

### allowed fur charaClCril.aLIon oflhc exlernal morphology ofthe particles and calalysl surface. The samplcs mounled in resin were cross-seclioned and polished, which allowed for more delailed and ljuantilalivc analysis ofthc honding malerials and matelials Ihat accumulatell in Ihe porc>: {l[

### Ihe calalysL Delailedinformation on allihe samples can be found clsewhere (add FPT reference). Exmnples oflwo deposil and calalyst analysis are presenled here.
"l

### he 6-month sample from the Baldwin Slali"n 8howed eden.,iv" suifalion ofIhe alkalineearth elemenls presenl in the deposits. Figures 15a**~nd** 

### 15b show regions oflhe ealalysl where all lhe pores were blocked and a minimal amount ofdeposit on Ihe surf..1ce oflhe**cat~lysl.** 

### Figure

### '- '



# *- 

# " 

# I w**i;l~** 

### 15c shows a higher-magnification view ofthe deposit that is tilling the catalyst pore. The deposit con8isls ofpartie]es offty ash bonded togetherby a matrix ofcalcium- and sulfur-rich material, likely in the form ofcalcium sulfate. The chemical compositions ofselected points (hatindicate the presencc ofhigh levels ofeaIcium and sulfilr arc listed in Table 3_ There is much more extensive bonding ofthe materials wilh the sulfate matrix as compared to the 2-month somple. In addition, there are some regions ofhigh levels ofcalcium, aluminum, and sulfurpresent. -nle calcium aluminum materials arc likely derived from the calcium aluminum phosphate minerals found in the coal fired at this plant. The 4-month samplc from the Coyote Station showed particles adhering to the surface and filling pores in the catalyst. Figure 16 shows the 4-month sample from the Coyole Station. The catalyst showedparticles adhering to the surfl\ce and completely filling and masking the pores in the eatalysL The external morphology ofthe catalyst surface shows the masking ofthe catalyst surf..1ce. Chemical compositions ofselected points arc shown in Table 4_The 4-month sample shows more sulfalion than the two months ofexPOSUfc samples. Figures 16b and 16e shows a bighcr-magnilication view ofihe dcpositthat is lilling the catalystpore. The deposit consis!... of particles ofily ash bonded togetherhy a matrix ofsodium-, ealcium-, and sulfur-rich material, likely In the fonn ofcalcium sulfate. Significant soo:lium was found in the deposits, as shown in Table 4_ The sample shows signilicantevidence ofsulfation after months ofexposure and was much more pronounced lhan lhe samples for the Baldwin and Columbia Stalions that are fired on """PRB coals. The preseuce ofsodium enhances the bonding and sulfation ofthe particles to foml a

-"stronglyhondcd matrix (22).

SCRDepositFormation Mechanisms TIle**mechani~TIl** 

### for the fOffilation ofdcposits thatblind SCR catalysts involves the transport ofvery small particles rich in alkali and alkaline-earth e1emenls, the surface oflhe catalyst, and reaclions with SO,/SO) to Conn sulfatcs_ The fonnation ofSO) from 

### SOz is catalyzed by the SCR; this, in tum, increases the reaction ratc ofSOJ 

### to form sulfates_ 

### In some cases, the alkali and alkaline-earth elemems will also react with CO, to form carbonates. XRD analysis Identified CaS04 as a majorphase and CaJMg(SiO.), and CaCOJ 

### as minorphases. Lignile and subbituminous coals eonlain high levels oforganically associated alkali and alkaline-earth elements including sodium, magnesium, calcium, and potassium, in addition to mincrnl phases. The primary minerals present in these coals include quartz, clay minerals, carbonates, sulfates, sullides, and phosphorus-contaIning minerals (6)_ During combustion, the inorganic components in lhe coal are partitioned into various sIzc fractions based on the type ofinorganic component, their association in the coal, and combustion system design and**oper~ting** 

### condilions. Significant research has been conducted On ash fonnation mechanisms and rclnlionships to impacts on powerplant performance (1---6, 9-13, ]9- 21, 29). During combustion, [he inorganic componenLs associated with western subbitumillous and liguile coal typically are distribllted into various size fractions ofash. Thc smaller size fractions ofash are dominated by partially sulfated alkali and alkaline-earth elements_ These ash particles are largely derived from the organically associated cations in the coal. The larger size

### fi-dClioo has higher luvels ofaluminum nnd silicon derived from lhe mineral fraction ofthe ashforming component ofthe coaL Enlrdined ash was cXlracted from the Cohlmbia Slalion at the point ofthe inlet to the SCRreactor and was aerodynamically cla<;sificd and ollalyzed. Thc composition ofthe size frncliollS wns compored 10 lhe chemicol composilion ofthc ash dg]()siled on and in the calalysl, as shown in Figure 17_ TI1C 

### comparison shows thol Ihe comp08itioll ofthc particle c,1plured ill the SCR calelysl is very 8imilar 10 the <5-flm sizc fraclion, The dcposited matcrial shows significnntly more sulfalion then the entrained-esh**siz~** 

### fraclion, indicaling Ihnl thc sullation process occurs after the particlcs are deposited ill lhe catalyst. The mechanism ofSCR calalysl blinding when firing lignite Or subbimmillolls coals is shown ill Figure 18 (JO). The requirements for lhe fomlalion ofdeposils thai blind SCR calalysl include filing a cmd Ihal produces signifieanl levels of**<5-fllll-5i~ed** 

### particles. The parlicle." ore lransported inlo Ihe pore:; oflhe ealalysl and subse(]uently reael wilh SO, 10 form suIfal,,""_ The sullilte [orms a mntrix thnt bonds olhernsh pnnicles. The SCR ealaly/.es the fOlmation ofSOJ 

### and lhereby increases lhe rate ofsulfation (24, 25). 'nlC sullution ofeaO increases lhe molar volume, resulling in lhe filling oflhe pore. For eoals thai have high sodium conlents, fOlTIlalion oflow-melling-poinl phases sueh ns pyrosuUates is possible (3 I). Pyrosulfole malerials can mell at lemperalures as low as 535"1' in eoal-fircd power syslems.

0.025 0.030 Fe"" 

# "" Welghl Gain lorLSUS-PR8 Blend

/I;lOOOF 

# I 

# r 700'F

__-600°F 

# /**~.**


## .- -_._-_. - 

# ,
o

## o 0.020

0.010 0.015

0.005 c 

# •• 

# "

Time, min Figure 8. Wcighl**changc~** 

### for PRB-blend coal ,,-,h exposed to flue gases and ammonia al lhree lemperatures.

# ,**~--** Baseline and Catalyst Testsfor PRB 

# , / PRB 

### + Calalysl 

# , 

# !**P~** Baseline 

# , , 

# I 

# , 

# I ,
, / 

# , 1/ 0 0_00 0.00 L 0> 0.00 

### E 

# - 0> 0.00 

## E
c 0.00 

# • co 1: 0.00 

### 9' 0.00


# -

# ..



# " Time, min 

## "0 

# ''''
Fignre 9. Weight changes for PRB-blend coal ash exposed 10 nne gases and ammonia wilh and withonl SCR calalystpresent. ,]; 

# "**'-~** 

# "
" L' 

# a

" I 

# " c
U 

# " 0.' 

# i 0.' 

### 0 0.- 0.2 0.0 0 200 600 800 

### 1000 

### Run Time, hr "00



### Figure 10. Catalysl pressure drop al Baldwin Stalion al 

### 0 10 2 months ofopcration.

### '2T-------------------------'"~~"~~~"-'\ 

# wt------c----;------------1**o~** 

# I 0.6-1-----

c 

# '----cf- -0 0.6, 

# < 0.4 

## o 

# 0.'-1-----'----'----"---------++---1

1500 

## moo**oo+------~------~----"'''----j** 

# o Run Time, hr

Figure 11. CalalyGl pre."urc**~n)p** at COILl",hi" SlattM at () 10 2 month' of01'C"U;Ofi.



### '.0 

## L" L' 0

# - H I

### c 

# " U 

### , .0 

### ti 0." 

### 0.' U 

### 0' 0.' 00 0 1000 

### Run Time, hr Fig"re 12. Calalystpressu'. drop at COyulc SlallOn "I 0 [0 2 munlh, ,,! opomlion.**~-,**



# " " g " 

# "

. 

# ., Baldwin Slation arler2 months

COylJte Slation llfler2 months

ClJluwbia StatilJn 311er2 months

Figure 13. Piclures ofcatalyst inlet after about 2 months oftesting at each plant.o



# ,
, 

# : \ 

# '. ,

._, 0 F'RG "",,,",,,,eM _A> ';',

## '~&; 

# ",,-," ,.,'.c;-

:7 \. 

# , , , 

# , 

# , Baldwin Station arlcr 4 months

Coyote Slatilln after 4 month.

Figure 14. Piclure, 01" ".loly" inlet aflcr alm"1 4 month, ofcxpo,ure [" llue MOl "nd p"nirulalC.A



### B



# c

Figure 15. SEM images ofasn collecled 011 calalyst surface at !heBaldwin Station after 6 momhs ofexposure. A) ,md 11) low-magnification images ofash deposit on calalyst surfaceand 

### C) high-ma!1'ifiealion image ofpolished eross section showing pmliclcs ill a malrix of calcium- and sulfur-rich lTIolerials.**T.I>I~** __**~.!'.~nlj<"1** Composition of**S<ledt~** Points**"nd.;\.~o"s.** 

### i." F:igll.c" 15

- 

## ..---- Chomical cumpu,ili[]n (um1l1llIize-tJ wl% eqllivolent oxide) _._--- Oxide Poinl 

## , Point 1 I'oim J Poin!4 P"in[ 5 Point fi 

### 1.1.1 M '0 

# " o, 0.5 

### n

Na,o 4.3 2.5 0.3 

# e, Ui 7_6 MgO 14.8 10.0 15.0 155 14.7 

# e.o Al,O, ),3 U 18.8 'i7.7 

### n 47.3 SiD, 

### n 2.1 

# e, '.0 

## '0 

# ,., P20 , 30.7 20,4 17.7 

# "."**2~.O** 

# '" SO, 

# "' "
" 

# "' 

# " " K,O 28,8**2~.7** 28.1 22.5**34.~ 2~,4**  

### C,O 

# '" " " CO L3 

# " TiO, 11.4 ]2,9 

# "' o.e H**7.~** Fe,O, 

# "

" 

# " ,e o.e 

# " 0,0

._- 

## . Tolal 

## W" W" 

## W" '00 W" 

## '00
Oxide Poin< 7 P"iu[ PlIim9 l'oin!IO Point II Poinl 12

_..._.- ._-_.



### 1.1.2 

### u 

# "' 05 

# " U
" Na,O 

# " 0' 

# ,., '" H 0.' MgO 

# ,. " 3.0 19.2 10.8 

# " Alp, 

## 0' I8.4 18.5 JI.O 17.4 10.7 SiO, U 

### 0.' 

# '" ".e u 

## ,-' 1',01 37,9 U 5,3 

# ".e n.s 13.9 SO! 

# e, 

# ,." 

# "" "., '.K 

## "-" K,O 31.4 52.6 49.0 28.9 30.0 45.4 CaO

" 

# ., " " " " TiO, 

# " 

# " 0.' 0.' 

## o., 0.' h,O, 

# "" '.0 

### n ,1.2 2.Y 

# " BaO

Totfll 

## W" WO 

### WO 000 

### W" 

### W"

### A

B



# c

Figure 16. SEM images ofash collected on calalysl surface allhc Coyole Slaiion aller4 months ofexposure. A) 

### low-magnification image orash deposil on catalyst surface, B) low-

### nwgllifiealion image ofpolished cross section showing p;n1ic1es in a matrix ofcaJciulll- and sulJiJr-rich 

### malerials, and 

### C) highcr-nmgniJication image ofbonding. 

### 1.1.2.1 TaJJ.le 4. Chemical COlllposition ofSclccLcd Poi"ls nnd 

### Areas in Figure 16 Chernic,l**~"IIlJl,,,ilion** 

### (uormali,od wl% 

### "'luiv,lenl oxide) Oxide

# ---",""""",==="C"Cm"C,~ Poilll3 Point4 PoilUS 

### 1.1.3 6.7
" 

# " 6.2 3.1 N"O

" " U 

# " " M,O 2.6 U 

# " U 10.5 AI,O, 

### '0 21.1 113 5.6 32.2 SiO, 02 

# " 

# " OJ**O.~** P,O, 54_7 38.5 56.4 57.5 30A W, 

# '" '" 0' 

# '" 

# " K,O IRO 3.4 15.8 9.3 D CoO 

# "' "
" 

### u
" TiO, H 

# " " 

# " 

# " Fop, 

# ,., 13.' 00 

# '" ,

# .. 0,0

----- -----------

Tolal 

## '00 '00 000 

### '"0 WO O.ide Poim6 Poln! 7 Poinl S Poinl9 

### Poinl 10 

### 1.1.4 

## 0.' 

# ,

# .• 10.4 

# '" '" No,O U 

# '" U ).0 U M,O 

# ,

# .• " "' 

# '" 10.6 Al,O; 6.3 18.2 10.5 

# '" 28.9 SiO, 

# "' , .0 

# "" O. , 

# "' P,O, 

### I.B 28.4**~~.9** 

## «., 23.4 SU, 

# " 4.3 

# .., '" H 

### K,O 24.5 

## '0 22.5 lH 

# " C,O 0.' 0.' U
" 

## u nO:, 

# " 

# •• LO 

# " 13.2 !'e2O, 

# " 22.) 

## 0' 

# '" 6.3 

### 0,0

-- .00 00' 000 Tolal

# =~f~~~~l===========~~:IT:~:":IT'-:~~ ,,- 121 <lJ1rn 

## E8 1 104.6 J1m 4.610 22J1m L

_ 1i!llI>22/lm I 

## EE Catalyst Ash 

### E 

# " 

# • rn 

# "**.~** 0 

# Jr 20 

# * ,. 

# " rn 

# • W 

# " ,
0



# '" 

# i 0 

# ,'" Figure 17. Comporis"" ofonlrairu,ci ash and "<posited ash oncalalys( for Columbia Sialion.Pore Sulfur Oxides Carbon Dioxide

No Dcteriomlion Yet (NHJ and NO, can react 

### in micropore on catalyst surface)

- Reactions with SO,

and CO2

14% Expansion

### /~--M"'ri' Mo'''''''''

_ ,,"IIy Sulfa'.d AJk.dh

### on~ Mkal;oe·EMh 0"-'""

'- P"",das

_ 5,I,co'0, 000 OLher Fly II.Sh

## p"",",,,,

Deterioration (NH J and NO. cannot react 

### in micropore on catalyst surface)



### Figure 18. Mechanism orSeR cntnlysl hlinding via the fOffilolion ofsulfates and carbonates (IlIodiIicd after Pritchard and othcrs r30])_


### Low-Tcmpcraturc Pyrosulfates Thc presence ofsodium sulfale in Ihe 

### nuc gas exiling a scrubber will 

### call'" problems 10 low-dust and lail-m<l**devi~e"** 

### such as selective calalytic redudion (SCR) 

### syslems forNO, 

### redUClion. There are two problems associntcd with the line parliwlale rich in 80dium sulfntc on downsLJeam devices. These include accnmulation offine particle, on lhe SCR 

### lhat, when sOOlblown, will cause opacity problems, and lhal the fine particles on the SCR 

### will fonn pyrosulfales such as**(K,.~a** 

### O.j**)S,~** 

### thal have mehing poinls as low as 535"F (31) 

### lhat will blind lhe catalyst The**pr~,~nce** 

### "fthese eom[>ounds in low-lemperalure CO[fo,ion deposits is well known (32). In addililln, Ihe presence orso, enhances lhe lormnlion ofthe low-meltingpointpyrosulfmes (31)_ The sodium sulfale mamrials will cause opacilY nnd SCR 

### calalysl

### ;;;" 

## lli**~~** 

### blinding problems lhallimillhe feasibilily ofthe 10w-t1uslor lail-end SCR lcchnology for usc with high-sodium lignite eoals_ The sodium sulfalc materials will be 1r;msported 10 lhe ealalyst surfaces by diffusion, dcclrophoresi8, and, possibly, inertial impaclion. The particles**~re** 

### hcld in place by we.1k eleclroslalic and van der**Wa~ls** 

### forces_ Once accumulalion lakes place, lhe sodium sulfale particles will react wilh Duc gas components, resultIng in lhe formation ofpyrosulfales. The fOmJaLion ofpyrosulfates involves the followingprocesscs (31):


### 1. Formalion ofsulf"le.<; such as NaZ S04 and K,SO. 

### 2. Conversion ofSO, 10 S03 in lhe bulk gas phase

- catalytically adive surface such as an SCR calaly:;l

- SO, 

## + Y, O2---Jo 

### SOl 

### 3. Pyrosulfale formalion

- Na2S0. 

## + SOl ---Jo**Na2S~Q.** 

### The melting poinls ofseJecledpyrosulfate phases are shown in Table 5_



### Table S. Mellin!! Points or Selected Pvrosnlfale Compounds CompulInd Temperature, "C Temperature, OF



# - .. 

# - ----- Kj

### Fe(S04), 

### 618 1I44 

### Kj

### AI(S04)1 

### 654 1209 

### KFe(S04)2 694 1281 

### Nn]Fe{SO')J 624 

### 1155 NnlAI(S04)J 646 

### 1195 NaFe(S04)2 690 1274**Na~S~Q.** 

### 401 754 

### KlS:!Q. 300 572**(K15N~.,)S,Ol** 

### 279 535


### Melling poinls forpyrosulfates belween 535 0 

### and 770"F 

### havc been reported in the lileralUre. Much Oflhe past workhas focused on lhe formalion oflhesc phascs on tube surfaces. These species contribule to lhc corrosion ofheal-traIlSfer surfaces in coal-fired powerplants. The exact rnelling point depends On lhe reinlive amounls ofsodium and/orpotassium. 

## , There is significant evidence for lhe formation ofsodium·rich fine particulale in full-scale powerplants when firing high"sodium-containing coals. Forexample, MinnesotaPower's Boswell Energy Slalionfound that w]lcn il fired high-sodium, lower-"8h 8ubbituminous coal, it experienced increases in opacily. Hurley and Kalrinak (33) 

### condueled a field-testing projecton Unit No_ 4, apulverized coal-fired boilerequipped wilh au clectrostatic prccipilalor and awei 

### scrubber, 10 beller understand lhe reasons for the opacIly problems. During lhe field lesling, sampling oflhe coals, nue gases, and scrubbermaterials was eonducted_ The particulale in nile gases downslream orlhe scrubber was aerodynamically classified using an impactor and

### mllllieyc1one. The**si~.ed** 

### Ii-action., were analyted 10 delermine Ihe composition oflhe subminonsized fraction.

The T1,"uIL, o[the .'lully indicaled Ihat the partieulale collected downslream ofthe ",cmbber was cO;1J-relaled ami caused by thc high sodium contenl "I' 

### onC ofthe coals. Vapor-phase sodium condenses in the conveclive pass 10 form line sodium sulfate**]Jartic1e~** 

### or olher Na species Ihal Inter react with nsh pnrtic1cs. Pure Na,S04**p~rtides** 

### are 100**sm~llto** 

### be removed by seruhhing.
CONCl..LJSJON, 

# sen IS NOT FEASIBI.E FOR NO); TtEDUCTION AT MII:rON R. 

### YOUNG The ilsh dep08itioll behovior ofthe lignites from North Dakota is the illo,t cnmplex and severe OfollY coals in the world, md inslallalion n[catalysts for NO, redllcti'!n is going 10be impossible because ofthe fOlmatioll ofsodium calcium suIfales in thc pores u[the calnlysL Following is a list ofthe key roodbloeks associated with lignites which have not been OVercome and, in our opinion, makc Ihe inslnllalion 0 fSCR c;ilalysl ill the lVlRY plant lechnically infeasihle for NO, control.

• High olkali ond alkaline-earth clemenlS**pres~nt** 

### in the coal fired althe MRY plant form sulfalc.s Ihat blind Ihe catalyst.**Cyclon~-firing** 

### partitions thc ash during combustion. As nrcsult lhe level of sodium and calcium in Ihe fly ash is enhanccd and win i"crcase the SCR catalyst hlinding_ Sllifale reaclions increase with**incre~sing** 

### temperalLLre, and th" wggc--Sted temperalure ofinslnlIalion at the MRY facility is higher than typical installations; lllCfcfore, sulfation problems are enhanced. Sulfole formalion is also enhanced by Ihe presence ,,[an SCR calnlyst; this**accelcr~les** 

### Ihe suJralion reactions, causing blinding 0 fthe calalyst. The high levcls ofsodium in the cOols combined with calcillmprodllce., low" ruching-poinl euteclic compounds Ihnl will mell on Ihe sllrf..1ce. Sullalcs form on the**surfac~s** 

### ofcolnlysls firing PRB COols. Lignites wjll bc several ordcr:; ofmagnillldc worse becnusc ofthe higher Icvels ofsodium.

• The ash components 10 impacl SCR**perfomlanC~** 

### in Japan and Europe (14- 

### 16)**includ~** 

### alkali and**alkaline-e~rth** 

### clemcnls lhatresull in sulfale forolation_ The**lol~l** 

### caleilllTI content and the sum ofthe calcium, magnesillm, potassium, ond sodiumprovi(le an indicalion Oflhc problems that OCCUf_ For the coals lircd al [he MRY**pow~r** 

### plant, Ihe CaO content ranges from 6.80/0-] 9_99%, 

### and the Sum oflhe alkali and albline-earlh**elernent~** 

### range from 9.330/0-29.87% 

### ofthe**a~h_** 

### The levels ofcalcinm in Centerlignite are 2 10 4 limes higher than Ihe problematic coals in Jilpan and Ellrope.

• TIle finding or work conducled in GemJany and**Jnp~n** 

### were confirmed by recent SCR catalysl slipSlream tesling Ihnt showed significant cvidence ofsodium and calcium-

### rich sulfate fonnation that fill and plug the catalyst atboth lignite (North Dakota)- and subbituminous-coal-firedpowerplants_ The results orthis recent testing showed that the presence ofsodium significantly enhanced the fonnation of bonding ofparticles and more rapid sull:'llion, filling ofpores, and rapid increase in pressure drop aCross the catalysL

• Deposit cl\fl)'Ov",-, urpopcorn ash, plugging the top ofthe SCR catalysl with deposit fragments, is a significantprohlem because orthe extremely high deposition potential orthe coaL The formation ofdeposits in various parts orthe boilerrequires continuous sootblowing_ The deposit fragnlenls are likely going to be camet! with the bulk gas 

### flow to the SCR catalyst, rcsuhillg in plugging. The variability oflhe lignite is a problem ofunique concern atMRY. The deposition potential ofthe coal is always changIng mpidly, resulting in rupid growth and formation ofdeposits in various sections ofthe boilcr. Aggressive sootblowing ofall fireside surfaees is aJreiuly required Lo maintaIn full-load operation. The sootblowing of upstream heat exchange equipment will cause deposit fragments to be carriedback to the SCR catalyst, and during sootblowing ofthe SCR catalyst, tbc entrainment of deposit frngments 1Iiong with the sootblowing media will result in significant erosion of the catalysL surfaces. The ash-related impacts ofthe ligniles from NOrth Dakota are the most complex and severe ofany coals in the world, and inslallation oftail-end SCR systems for 

### NO, reduction will not be possible. The key problems nssociated with lignites Lhat bave notbeen overcome nnd, in our opinion, make Lbe instalbtion oftail-end SCR systems at the MRY plant technically infeasible for NO, 

### control at MRY's Units I and 2 nre listed below:
X High-sodium lignite coal from the CenterMine Hngel A and B seam coal produces extreme levcls ofhomogeneously condensed sodium sulfate ton! pass through the wet scrubber. Tn nddition, the cyclone-firing system captures much orthe nsh as slag, resulting in a decrease In ash that is available forproviding condensation SileS forvaporphase sodium compounds upon gas cooling. This resulls in an increasedhomogeneous condensation ofsodium sulfate.
X These small particles pass through a wet scrubb",- and 

### will accumulnle on surfaces oftail_ end SCR syslems. The accumulated materials cannot feasibly be resolved through conventionnl sootblowing and cleaning technologies to remove the prutieulnte.
X Recent testing**Wi~l** 

### subbjtnminous nnd lignitie coals iudicllted a signifiennUy higher level ofpore filIil1g and plugging in lhe entalyst exposed to ligniLe ash as compare to 

### subbituminous coal ash. The catalystpores as wel] as lhe catalyst surface in the lignite tests were completcly coated with a sodium calcium sulfate material, while only pore filling was found in the subbituminous coal testing. The pressure drop aCross lhc catnlyst exhibited for lignite was 4 to 5 times greaterthan that found for a entalysl exposed to subbituminous coal ash. The plugging occurred ov",- a 1000 hour testperiod.

### The fOimalion ofli(jllid**pyroSlllf~le m~lerials**  

### ;lllemperal"re.< as low as 535"1' Ii-om sodium sulfate materials oecurs in eoal-fired power syslems and is well documenleiL Pyroslilfalcs 

### will lorm and eausc blinding oflail-cnd SCR dcvices.ln addition, SCR sysLems**caL~ly,oe** 

### Lhe fonrmLi"n ofSOJ 

### fwm 

### S02. The**pIT~cncG** 

### ofSOJ 

### sigoificanlly enhances lhe Iomlalion oIlhe pyrosulIales al MRY 

### to an extreme 1cvellh"1 cannot be deaH with effeclively u'ing cleaning lcehnologies thai cxislto<.1ay.

REFERENCES


### I. Mehla, II.; Benson, S., Eds. 

### EJJecls oj Coul Quality Oil 

### PowerPlu,,/M"",rgcmelll: A.,h ProMe",,,, Jl1a"agemeJlI. "lUISolu/io/J.I'; lJniltd Engineer;ng FOllndalions Int.: Ntw York and 

### ErRl: Palo Allo, 

### CII: 2001.
2. 

### Schoberl, RR 

### i.ignites of North Amerira; CoafSciencr and Techllology 21.'**El~evier:** 

### New York, 

### 1995. J, 

### Baxter, 1..; DeSolJar, R., ros. 

### App!icafiol/s of Adva"cedTechnology to Ash-RefutedProhlem.< in Boikrs; Plenum Press: New York, 

### 1996.
4. Couch, G. 

### U"dcrs/III1Ji"f{ SloggingamfFuuli"g DuringpICvmbusrion; lEA Coal Re'earch Report; 

### 1994. 5. William.lon, 

### J.; Wigley, E, Eds. 

### The Impact of As!llJeposition all 

### Coal FiredPlants.- Proceeding., aftlle F:lJgil1eering Faulldotion Conference; Taylor 

### & Francis: Lon<.1on, 

### 1994.
6. Ben8on, S.A.; Jone8, 

### M.L; Harb, J.N. Ash l'ormarion and Dcposilion-Cb"pleT 4. 

### In Frmdamemals of Coal Combuslionfor Clean andEjjicieIJ/ Use; Smoot, L.V., Ed.;**El~evier:** 

### Amslerdam. Londoll, New York, Tokyo, 

### 1993; pp 

### 299-373.
7. Bcnson, S.A-, Ed

### .I/lorganic Tra,,40rmal;'J/is andA.<h Depositiu"During Comlmslion. Americon Society 

### oJ_1I,.1cehanieal Enginecrs lor lhe Ellgineering Foulldmion: New York, 1992.
R. Bryers, R.W.; Vorrcs, K.S., Ed". 

### ProceedilJgs of the Engincerillg Fowulatifm Cmifcrellce A" Mineral Matter u"dAsh {)epositioJlfrail! Coal, SantaBarbara, CA, Feb 

### 22-26, 19S9; Uniled Engineering Tmslees lne.,**19~O.** 

### 9. Raask, E. 

### Erosion Wear in CoofWilily Boilers; Hemisphcre: Wnshington, 1985.
1

# o.**R~a,k,** 

### E. Mineral Impurities ill 

### enal CombustIon; Hemisphere: Washington, 1985. 11. Benson, S.A., Ed., 

### Ash Chemistry: Phase l/e!ariollShips in

### Ashes andSlags, Speeiallssue of 

### Frle! Process. Techl/ol.; Elsevier Scicnee Publishers: IImslerdnm, 

### 1998; Vol. 56, N,,". 

### 1-2, 168 p. 

# ..,

### ,



# " 12. Laumb, M.; Benson, S.A.; Laumb, 

### J. Ash Behavior in Utility Boilers: A Decade ofFucl and Depo5il Analyses. Presented at 

### the Uniteu fuginccring Foundation Conference on Ash Deposition and Power Prolluclion in the 21st Cenlury, Snowbird, UT, Oct 28

- Nov 2, 2001.
13. Benson, S_A_; Hurley, J_P.; Zygarlicke, CJ_; Sleadmall, E.N.; Erickson, T.A- Predicting Ash Behavior in UtilIly Boilers_ 

### Energy Fuels 1993, 7 (6),746-754.
14. Licala, A.; Hartenstein, H-U.; GUlberlet, 

### H. Utility Experience with SCR in Germany_ 16th Anlluallnlcmalional PillShurgh Coal Conference, Pittsburgh, PA. Ocl 11-15, 1999. 15. Cichanovicz, J.E.; Bruske, D.R. An 

### Assessment or-European Experience with Selective Catalytic Reduclion in Genuony and 

### DCJUnark. EPRJ-DOE--EPA Combined Utilily Air Pollution Conlrol Symposium: The MEGA Symposium, Allanta, Georgia, Aug 16-20, 1999. 

### 16. Cichanovicz, J.E.; Mnzio, LJ. Twenly-Fivc Years ofSCR Evolution: Implications for US Applications and Operation. EPRT-DOE-·EPA Combined Utility Air Pollution Control Symposium: The MEGA Symposium, AWMA, Chicago, 

### IL, Aug 20-23, 2001. 17. Benson, S.A.; Kong, L; Katrinak, 

### K-; Schumacher, 

### K. Coal Qualiry Management Sy.<tem; Final Report for North Dakota Industrial Commission; Sepl 1997. 

### 18. Kalrinak, 

### K.; Benson, S.A; Lmunb, 

### J.; Schwalbe, 

### R; Peterson, W. 

### MatchingLignite Characteristics alldBoiler Operation; Final Report forNorth Dakota Industrial Commission; Aug 2000. 19. Sarofim, AT; Howard, 

### JJl; Padia, A.S. TIle Physical Translormations ofMineral MaHer in Pulverized Coal Under Simulated CombustIon Condilions. 

### Cambl/st. Sci. Tech"o!. 1977, 16, 

### 187. 20. Loehden, D.; Walsh, P.M.; Sayre, AN.; Beer, I.M.; Sarofim, A.F. Generation and Deposilion ofFly Ash in the Combustion ofPulverized Coal..J. 

### l"s/. Energy 1989, 119-127. 21. Zygarlicke, C.J.; Toman, D.L; Benson, S.A. Trends in the Evolution ofFlyAsh Size During CombUSlion 

### Prepr. Pap.-Am. Chern. Soc., Div. Fuel Chem. 1990,35 (3), 621-636.
22. Benson, S.A.; Fegley, M.M.; Hurley, J.P.; lones, M.L.; Kalmanovitch, D.P.; Miller, B.G.; Miller, S.F.; Steadman, E.N.; Schobert, H.H.; Weber, 8.J.; Weinmann, l.R.; Zobeek, BJ. 

### ProjectSodium: A DetailedEvaluation a/Sodium Effects in Low Rank Coal Combustion Syslems; Final Technical Repnrt; EERC publicalion, July 1988.
23. Hurley, J.P.; Erickson, T.A.; Benson, S.A.; Brobjorg, J.N.; Steadman, E.N.; Mehta, A.K.;**Schmid~** 

### C.R Ash Deposition allow Temperntures 

### in Boilers Firing Western U.S. Coals. lnlemntional Joint Power Generation Conference; Elsevier Science, 1991; pp 1-8.

### 24. Laurnh, J.D.; Benson, S.A- Dench- and Pilol-Scale Sludic.> o[SCR Calalysl Blinding. In 

### Proce('aing

# fir PowcrProduction;1l [he 21s1 

### Century: Impocts

# fir Fuel QualifY ond 

### Oper(l/;ons; United Engineering Foundalion: Snowhird, UT, Oct 2001.
25. Crocker, 

### c.R.; Benson, S.A.; Lmuub, J.D. SCR Catalyst Blinding Due 10 Sodium and Calciulll Sul[ale Formalion, 

### Prepr. Pap.-Am. Chern. Soc., Div. 

### Fud Cbem. 200449 (I), IG'l. 26. Benson, S.A.; I.aumh, J.D.; Crocker, C.R, BJimling o[thc SCR Calidy:;ls ill Liguile and SubbiluminOIlS COid-Fired Powcr Planls, Prcseoted ai The Clcnrwnter ConferCllcc On Coal Ulilization 

### & Fuel Systems, Clcnrwaler, FL, April 1R-22, 2004. 27. Senior, c.L.; 

### Linjcwilc, T.;**Dcni~on,** 

### M.; Swensen, D.; Shino, D.; Boekdie, M.; Baxler, L; BartholollCW, C; Hecker, W.; Guo, X.; Nackos, A.; Whilly, K.; 

### Eddings, 

### E. SCR Deaelivalion Mechanisms Relaled [0 

### Alkali and Alkalinc Earth Elemenls, 200] Conference on Se1eetive Catalytic Reduclion (SC1t) alld Selectiye Non-CalHlylic RedUClion (SNCR) ror NO, Conlrol, Pillshurgh, PA, Oct 29-30, 2003. 2g. Righy, K.; John.<on, R.; Neufort. K; Gunlher, P.; Hums, n.; Klalt, A; SigJing. R. SCR**Calaly~l** 

### Design TS8UCS and Operating .Experiencc: Coals with .High Arscnic Conccntralions and Cmds from the Powder Riycr Basin, Presenlcd allhe lnlcrnalional Joinl Power Gener"tion Conference, IJPGC2000-15067, July 23-26, 2000. 29. ASTM Mcthod D6784-02, "Standard Te'l Method [or Elemenlal, Oxidized, ParticJe-J3ound and Tolal Mercury 

### ill Flue Gas Generaled fmm CoakFired Slationary Sources (Ontario Hydro Mclhod)," at 

### hllp:l!www.a'trn.orglcgi-hin/SoflCan.exeJDATA13AS.E.CART!PAGESI**D6784.111In?E+rnysto,~.** 

### 30. Prilchard, S.; Hellard, D.; Cochran, 

### J. CAlalyst Design Expcriencc for 640 MW Cyclone EoiIeI' Fired with 100% PRE Fuel,**!lJill:!!Vvw~_.corlllcleeh.comll.9~l1ql!lali** 

### 114e)i.hlfllL ]]. Singer, J.P. 

### Combuslioll, FossilPowerSyxlems, 

### Comhustion Enginccring Inc.: Winds"r, CT, 1981.
32. Chemislly 

### a/Coal Utiliza/;on,**S~eond** 

### Supplementary Volume. Elliot, M.A, Ed.; Wiley Inlerscicncc; Ncw York, 1981.
33. Hurley, J.P.; Kalrinak, K.A. Delerminalion ofAsh Formalion and Deposilion Mechanisms al**Minne~ota** 

### Power Clay Boswell Slation; DOEIMC/I0637-]365, 

### July 1992.

## , APPENDIX C 

### COST METHODOLOGY CAPITAL COST ESTIMATE DETAILS 1,'ORNOx CONTROLS O&J\:f COST ESTIMATE DETAILS liOR NO

### xCONTROLS

### APPENDIXCI COSIMelhodology


### C.1 METHODOLOGY FOR ESTIMATED COSTS NOx BACTAnlllysis Study

The summary economic evalu"tions ofeach aHernative arCprcsenled in lb.e cost**imp~ct** 

### sections ofthe ill"in report. Capital and O&M cost estimate., foreach "licmalive are presentc""l individually. The Levelized TOlal Annual Cost (LTAC) for "lIlhe alLertUltives for control ofa single pollutant (i.e. NOx) frurn single unit is then prc>CTlted Logether with Unit O:mlrol Costs- The Lcveli7-"d ToLaI Annual Cost (Ll'

### AC) reprcsents the levelized annual cost ofprocurement, construction and operation over a 20 year dcsign life, again in current (2006) dollars. As a minimum, the d.,,;ign life for uny alternative waS taken to be tha( reoommended by**~Thc** 

### EPA Air Pollution Contrul COSl Manual", SixthEdilion, January 

### 2002, EPA1452/B--02-00Ii.

The LTAC is also used to ealculale \he aV"'""b'C**~nnoal** 

### and increment"l cost crfectiveness of"<leb allernative. T11e LTAC represent:; an annual payment in current day dollars sufficient to finance lb.e project over its entire life.



### In dctcrmining the LTAC u Capital Recovery Factor and an O&M Leveliz"tion Factorwere calculated from (he project economic condilions and then applied S""P"TIllely [() the estimated capital and O&M costs. The c(!uation used is shown below.


### LACCfNPV=( ;(1+;)" 

### ]=CRF (1+0" 1 Where, LACC = 

### Leveli2ed Annual Capi"'] CO't NPV = 

### Net Prcsenl Value or ille capital invcstmcnlS required. i di,count rate n = 

### design life in Y(:;lrs CIU' =**C~pital** 

### RecoveryFactor Therefore: LACC CRF x NPV

For the economic conditions deocribed in Table C.1_lthe Capital Recovery Faolorwas**calculat~"(]** 

### tobe 

### 0.08718.

In dClermining the**leveliz~"(]** 

### annual O&M cost the estimatcd annual O&M cost, the inflalion rate, the discount ",Ie, and the equipmc"Tl1 life are taken into account. The O&M Lcvelizalion F"ctor (OMLf) was cakulated as follows. MillnkOl. Power Coopcr.uve, hlC. Cl·t Dum' & 

### McDunnclJNOx BACTAnoly,i< Study



### rAOMCIJ1 =

# [I + i J

# -1][ i J

# (I**~O'** ] = 

### OMLF



### , l+i, (I+i_)'-I
Whore, A = I**.~vdizc,1** Annml O&ro.l Cost (LAOMC) A, 'rolal amlUol O&M eOSI in currcnl dollar" id ,hseolllli rale i; = intlotion ralc n - design Ji

## re ill year, Therefore, I.AOMC-OMLFxA, APPENDlXCl Cu.,l MOltodology

for**Ih~** {oconornic collditlllns**dcsorib~u** in Table C.I- I Ihe Opcf1lling and Maintenance**l.e~d;zalion** FaClor W,," calculaled 10 he 1.24873.

The Levdizou Totol Annual Co"l, Or LTAC 

### is Ihe sum oflhe leveli7ed "",pilal cosl and Ihe levelizc-d Q&M oosl. Therefore:

I.TAC LACC + LAOMC = (CRF x P) + (OMLF x A,) = 0.08718 x P

### + 1.24M7J X A,

The uiffercnces betweel\ ahem"li,'e, "re also pre,enled lI,"phio"lly in Ihe fOl'm ofu piN ofIhe annual emission, reduolion (tpy) versus Ihe LTAC for**~.ch** "Ilom"live. This I"nrrn ofplOI gr"phicolly depicls lhc co,teJYeclivelle.,S (I[ lIml Conhol COSL (io S/lrm ofpolllliant rednclion) ofc"oh "Ilelllalive relative LO "II ofll,e ,'lhers. The COSI effcclivene"' is abo refcrred to as the Unit Conlrol Cost and defJned"" lhe LTAC ulvidcd oy Ihe annual emi.<sion, n:dllelion (Ion/yl')_ TI,e are" on Ihe plolllldicaled by Lhc various data poinls represent, lhe cost**eff~ct,vcncss** envelope fm- the altL'TTmlive" undeL' consideralion. A**"mOO~l** Ii"c is d,,,wn on Ihi.' plOl Gunnceling Ihe righlmOSI ruinls (thusc w'lh Ihe loweot eOSI fur a given level of emissions reuuclion). Thi, li"e i:; rcfc"[nxllo as the Dominanl Conlrul Curve (DeC). Tk

## Dec define, Ihe righl hand oOlUldary ofLhe envdopc cncompassillg all of1he allemahves cOl\"idered. The DCC i" used as a .,e, eening 1001 belwcen con"ide",,j allcTImlives. Those alternativcs whose plotted posilion is ahuve and/or 10 (he left oflhe DCC "rc nOl as CO"1 ctleclive;," lho,e [OImlllg the line and Ihus can he eliminalcd from further analysi, ifdesired.

In order 10 comp"rc various pollu,"nl conlrol altemative.'<, ll,c Vnil Control COSL and lhc incremenl"llInil Control COSI ofeach "Hernaliw we'ro "Iso caJculaLed and**I~bllialed** [01' comparison pllrpoSe"_ Tile Unit
Bum, & McDonnell CI_2 MiTlJ1kola PowerCn0l'eralJ>", Inc.

### APPENDIXCI Cap;,.l CostEstim'les**NO~** 

### BACTAnaly.'is Sludy

Control Cosl compares conlrol lcchnologies on a basis ofdollars expended Il'" ton ofJXlllutanl reduced ($/ton)_ This relalionship is grnphicaUy clcpictcd in 

### lhe DCC chart.

To mOre aecuralely compare belween ahernal;vcs wllh differenl cosls and control effieiencies, lhe incremental cost effeCliveneSf; is also delermined for those alternatives on the DCC. The incremenlal cosl effectiveness If; defined as lhe LTAC ofa given conlrol oplion minus the LTAC ofan ullcmalive, divided by lhe difference bClwcen the annual cmissions reductio,n (tpy) ofthe given conlrol oplion and lhe ullCrnalive being evalualed. The combim,tion oflhe,e two eC<lnomic analyses enn 

### be used as an argument for the eliminalion ofcontrollechnologies wilh sib",ifieanlly greater marginal control eOSIS lhun the givcn
ease. Thc equalion use<! ror lhe ineremenla] cost eITeclivencgs is shown below.



### ICF =

## ,(l~"'~"~CL'**-~L~'~"~C2!')** (AE, -AE,) Where, rcI' = 

### Incremcnlal COSI effeolIveness ($/incremental ton removed) LTAC, Levellzed Tolal Annual Cost ofcontrol "llcrn"live No. l ($/yr) LTAC, = 

### Leve1izccl TOIUl Annual Cost orcontrol allernalive No.2 ($/yr) AE, Control oplion No. I Annu;,l Emissions Reduction (lon/yr) AE, = 

### Control option No.2 Annual Emission" Reduction (lonlyr) (Thc higher**C;Qs~** 

### mOre effective control oplion is subscripl I in lhis equation.)

The economic analyse, p,e,enled in this reportnol only include the e,timated capilal and O&M costs for each allemalive, but "Iso Ihe LTAC for economic comparison oflhc vnrions allematives. In addition, the Unl! Control Cost orcost cf[ee!ivencss is presented ror each**allcrna~ve_** 

### Finally, a comparison between alternalives, in lhe form oflhe marginal cosl effccliveness, is presenled in bolhnumcrieal and gnphical form. Thus a comprehensive comparison ofthe economic impacts ofcueh allemalive, as well as lhe dilTcrcnce. in economic imp"c! bolween allcmalives is olearly presenled.

Cl-J Dums & 

### MoDonnenNOx 

### BAcrAnalysis Sn,dy


### Table C.1·1 - Economic Factors(1),12)

TOlal Possible**Ope,min~** Hnll'-' peT YoaT Amort,zahon Life, YealS C"'lorMoncy PmportyTaxc" Ill,urana;, '};, Convc"i,m Tax (ill !lcu ufproperlY lax) Amorriza';on Ralc for APe Cap,lal CO.IL, InLcTc." During COll,lmcllOn (me) Di.<omml Role (llSe<! 10 calmlale NPY) Com'rucli"" Cm! Escalalion Non_Fuel O&M bcalallOn Fuel (rualm<! nalllrdll;a,) bc.Jaliun Aux,li.ry EIcciriG Power CU>I, SIMW-hr Uroa COSl, ($/Ion delivered, 50% oqueO\l' SOIUlioo) Nal",,,1 

### Ga, ($!I""ill"') (I) All fl"nci,,1 pmcn,,'g,,-' on" "",I ,,,,,,r,",y ,lccle;" I'ow" co" wetc pmvLded by MI'C. (2) • All co,,, ale io 2006 doll"" ""b, no,ed o'hrrwi",. APPENDIX Cl COSI Methodology

8,760



# " 6% 

## N' N' c% 

## ,% 6% 3% 25% 25% $35.00 $380.00

$7.98

lJurn' & MGDon"dl CIAAPPENDTXC2 Capilol Cost**E,~matcs** NUx BACT' Analysis Study

)"'. 

### C.2 NOx CONTROLS - CAPITAL COST ESTIMATES The oapilillcosts to implement Ihe various NO

### xwalTol tcchnologies wcre largdy cslimllted from unit oulpul espilal eosl faclon; ($/kW) published in technical papers discussiog Lhose conlrol technoiogie.,. 

### In the oases ofSNCR and FLGR, preliminary veodorbudgclory cosl infoffilalion WJa obhlincd nnd used in**ploe~** of, or 10 adjusI, Ihe pnhiished unil output co'l**r.~clor<.** ·lbese cost eslimale. were considered 10 be**~tudy** b'flld", '''hich i. 

### + or - 30% aecuracy, or herrer.

Thc hmilaLions ofLhcs" capital cosl e.timates developed from unil capil"l cos! fu"lors multiplied hy unit outpnl arc:

• Scope hasis unoertainty

- in"bilily 10 precisely delenninc whal scope ofsupply, including such Ihings as balanee-of-phmt (BOI') aysle'TIIs and cquipmenl irnprovcmeTl\S w","e required, a",umed,

or accounled for when developing the unit cosl facLors. Some ullcmalivcs may have highcr indirec\ or BOP capital costs Ihan others. Similarly, !he inchL.ion ofgeneral faoililic'S, pre"roducLion and invcnlory eosls, and other indirect oos\S is not known. II is likely thallhe ulility owner's fin"l lOlal expendilure for the implementaLion oflhe alternalives, especially options that arc mosl eapilal cost-intensive, WIll 

### be grealer Ih"n thc calculale'" costeslimales.

• LocaLion-specific influences

- mosl NOx control teehniques have been applied primarily 10 easlern hiluminous coal-fired planls localed near largc melropolitan areas, not in largely ruml, upper midwcolCrn United SlaLes iocaies. Thc amount ofspace available is r1cpcndenl On lhe exi.ting powc'TJllanL equipmenl ""d huilding layout and property plol area, vcrnuS what is**c~pecled** to be rcquired for implemenlingvarious comrol leclmoiogies. Tmnsportation and local/regional labor costs are also variables.

• Size influcnoes

- some leclmologies' capilal cost. are morc sensilivc to "economies ofscale" than Olhers.

• Capacily margins

_ some lechnologies' may require highcr capacity margin. 10 allow sustained operation al high lhroughput rale. over exlendcd periods oflime.

• Reliability ConcernS

_ SOmC lechnnlog'e.,' have b""T1 rcfined to a higher degree, and others may


### , require morc componenlredundancy Ibon olhers in order 10 avoid performancereduclions and pUleotial oUlages for failures and repairs or replaoerncnts.

• Inflationary iLlnuences

- Ih. significanL increases in 2004-2005 for mw material cll.SI<, especially sleel and alloys for fabricalion of<tructural JTId rnc-chanical componenl', has occurred afier many ofIhcsc teehnologies were inslullcd in projeots upon whioh Ihe rcfcn:nced unit capilal cost faclors were based.

Minnkma Power Coop""'t;"e, Inc. Bum, & McDonnellNOx BACT An,lys" Study APPENDIX C2 Cal,il,l COSI blim.les

• MarkeL condilions

- 

### as demand increase.' for emission controls,**'Om~** ahcnmtive., betome mOTC cOSl_COmptlilive, whilc olhcTS 

### <I" noL This can bc innucnted hy lhe rdalive supply and demand for Ihc IGchnolog:y and number ofsupplie", who can rumish iL Thc <!cm"nd for ",me
allem"li

### vc, e,m abo 

### b<- sirongly influenced by the ,tringency ol-Iht luc"l, 'tate, and naliona] regulalory reqlllrements_ Schedule for implemtnlalio" and availability ofloe"Ifrcgwnal labor for in,lallalion eonlraolors are "Iso markcl-drivL'Tl [actor,.

TI,e e,limaled NOx conlrol co'L' ate in addl110n 10 eaplla] co,l" 10 provide ""rm"l rcpl"cemenl, ofIhe exi,tiLl?, 

### Mil10Ll 

### R. Y

### OtHlg Sialion's majorpower generaLing equiprncm.



### C.2.1 Separated Overlire 

### Air 

### Capital Cost Estimates lnslallalion ofscpar"led overfire air sy"tems 'Yf',cally indu<1e., windbox and/or ,econdory comhllslion all ,upply ducL modificaLlOll.S, boiler waterwall tub" opc"11ing:;, uirnow di"tribulLon deviccs (damrers/regi>ler,,), airllow conlrol, oml rnC"Sluemenl instrument" lion, and rcbleJ ,lruelu",1 and**cleelri"alli~-Jns** to 

### lk c,isling pl;lnl faeililies_ A basic sepamled ovcrfire air retrollI .'y,lem in"alk<1 on a Iignile-fiIed cyclone boilerinclude, pOl'" acro,s the front and rear walls ofthe uppcr li,m"ce. The uml capital cosL faclor '" expected to be above Ihc hlg.b end ofIh" Iypicul publi5hed e",1 r"nge ofS5-IGfkW" ($12.0fkW 01' $],080,000';; for MRYS Unil 1), uue 10 Lhe large duels, rdalively Lall furnace (compared lu Iypical**hilurnin",,~** 

## toQ"q'n--u cyclonc boilers), and the need (0 avoid exi,ling oh;;buclions within Ihc IloileI hou,c.

An advanced IOl'm nl- SOl'A unique 10 Norlh Dakota lignite-fiIcd hOller>; wlll include relocalion 

### ofIhe exi'ling**lignil~** drying sysl= vcnt port openings from Lhe lower primmy furnace (0 the upper f"mace, to be placed al Ihe same e1evalion as Ihe new SOFA ports. This require" exlen"ion orlhe**c~istil1g** cyclones' lignite drying syslems' venLpiping tn supply Ihc new boiler rumuec 

### l'0rL'_ This i, expecled to cost in the

arca or+$4.7/kW Or approximalely $1 ,100,OOIl 

### fOl' Unil 1's additional eapllal co,t over and ubo\'" Ihe b"sic SOFA system. Ovemll, Ihe advanced version ofsepara(e<! ovemre air leohnology '" eslimaled 10 bave on in'lullcJ capilal cosl ofapproximaldy $i6_6/kW ($4.JMillion) for 

### MRYS Uml 1.

Dums &)o,kDorlllcll (;2_2 Mmnk<lla Pow"r COoporalive. Ino_

### APPENDlXC2 Capital Co,t Eslimiltes NOxBAC-rAnalysis Smdy


## C.2.2 Rebum Capital Cost ESlimates

".,

, , ':'" 

## C.2.2.1 Coal Reburn Capital Cost Estimates There is One**al~alive** 

### lhat includes a new coal rebum system. Capital co,t estimates for coal reburn
SYSlellL' 

### are highly dqlendent on the rcquiremems for reburn fuel preparation nnd feeding 10 

### lhc boiler. For the purposes oflhis "nuly:;i:;, the applicution ofa pulverized cnul rcbum system a5ffilmed the need to make extensive ad<!itions to 

### the existing fnel**pr~"p""'tion** 

### equipmenl in lh. exisling; planl facililies ;md feeding; to 

### new furnace injectors. Al leasllwo new fim'-gril\d pulverizers, or MI'S-89 slandard pulverizers followed by dynamic c1ussifi"rs are expecled 10 

### supply thc "mounl r>ffincly ground rebum coal 

### for lhis melho<1.

Addilion ofnew elecLriealload' for the pulverized coal preparnlion equipment to the exi.,ting plant facililies will be required. For 

### Ihe pttrposcs oflhis preliminary study_ il i" U8.Sumed lhat addilional plant**~uxiliary** 

### ekclri"ul powerwill be available forpowering the new**pulveriz£rs/mi~"To-milis** 

### an<! related new coal rebum**eqoipm~"Tlt,** 

### but Ihis has not been confirmed.

The.

### existing crusher roys do nO I 

### have floor space available 10 allow the new mining equipmenl for rebum fuel prepmmion to be localed adjaeenl lo Ihe eXlsling coal crushers. This will 

### require a scpa'--dlC building
or gddilion lo the cxisl;ng powerhouse lo be buill lO provide suffieienl space to enclose the new milling and coal silo/handling equipment. Separate modified**pul~cri?"d** 

### co"l-slyle humer< or ooal injectors 

### wllJ be installed lhrough new opening:; in tho upper furnace fronl afid rear**wal~T",all:;** 

### ut or ubove the elevalion ofthe exi'l;ng lib",ile drying system VCTll pons, along wilh new overfire airpons IO<;alc"{) ill a higher c!evalion, above the rebum fuel injeclors. This would have the capacity lo supply approximalely up lo thirly percenl ofthe total full load fuel heal inpullo lhc boj]er Lhrough the coal rebum injectors. This coal rebum syslem design was nul "xpeetoo lo change the exisling cyclone silo/feederarrangemenl, such thal all cyclones would remain operalional. To achieve maximum NOx emission control, only lhc**a<!v~need** 

### form ofSOFA for**pulveriz~-d** 

### coal rehum was included. Confirmation ofthese ooncepts and cosl eSlimates require, more delailed equipmenl design and planllayoullhan has been performed for the purposes oflhis BACT allalysis.

n,e insl"lkd capital cost

### ofpulverized coal rebum for the cycloneboilers al Milton 

### R. Young Slalion uscd in lhis cost effectiveness analysis was eslimaled ba:;ed upon a Clean Air Markets Division [CAMD] ofthe US EPA 

### dollar per**kilow~tl** 

### unit capital cost faclor for cyclones. The installed capilal eO,1 eSlimale of$21,900,000 forMRY Slation Unil l'spulverized coal rebum ultemalive used in lhis cost erfccliven= analy,i< was estimalo<! oo:;ed upon applying a 3.5% assumed inflalion coSl adju<lmenlLO the CAMD unil
Minnkom PowerCOOperali,'c, Inc. C2-3 Bum' & 

### MdJonnellNOx BACT Analysi' StuJy APPEN])]X C2 Capital C"'l E"irruJlc., capiml COSI l"olOr for cyclones of$82.33/kW (x 1.035 = 

### $gS.2/kW) ;ncludcd in a WRAP**(Wc~[cm** Regional A;rJ'artnersh;p) drnfl**report~** puuli&hed On**(h~;r** website, dalCrl April 26, 

### 200S. The cost to relocale the lignite dlying sys!cm**~"Tll** poTts (+$4.

### 7/kW) was addcd 10 Ihc infl"lion-adju.'lCd CAMD number ($S5.2 

### + $4.7/kW= $89.**~fkW),** :;incc eo"l rcbum i, l'xpccl"d 10 incllllk scp"r:ated m'cdire ;1irb"l nnl the exlm casts for lhc spceml improvemenls idenlilied 

### tor a;r-'lagerl lignile-fJrinll in cyclone bOlleJ

### s. This ;ncrcascd thc inslalled cap;lal cn,1 by SI,200,OOO for 

### MRY**S~lllon** Unil 

### 1', coal rellllnl sy,lcm 

### [0" to[al or$n,5('I,000. This <locos nol include the additional l,al1icula,e ",otlel colleetwn capacny consldcred nccc,,"my 10 limit Ihe expected**Il~"alive** imp"cl on opacily from Ih" opllOn.

To cOT,I",1 particulate matle, (PM) erni"lOns lhat would he expected 10 ;nerease Irnm inslaJlJtlOfi and opCr.Jtion "rpulverizcd or micronize,1 coal rehurn, additional 

### PM eolledion tapacilY w,nk reqUlrcd. 

### A hybnd form of

### PM collection Ihm supplemenls the cxi'lmg elcolrostnlic procipit"tor's performanoc, rcfcn-c<l to as COHl'AC (COmpaclllybrid 

### PArliculalc CollcclUr). ThIS 'vas cslimaled in 2002**,Iullar~** al S20,191,000 for MRY S[alion Unit I's COHI'AC. Adjnsted by an escalaliolllac[or of 1.2623, lhe instullOd eopJlal cosl oflhe COHPAC "ddilioLl 

### "lao cSlimated lO be $23,561,000 for MRY SLalioo Unil 1 in 1.006 doll.'I. Whcn Ihe COHI'AC addil"m "la, combincd w,lh Ih" Li!:oilc Rcb"", and ASOFi\ allemalives, lhe resulling lotal e.,[imaled c;lpltal cosls were $4(,,656,OUO for MRYS Unit 1**($~9.~** 

### +**$~L7 ~$IRI.5!kW)_** 



### C.2.2.1 Gas Reburn Capital Cost Estimates Convenlional gas rebum opllOns asoume lhal sevenleen pcrce--n! ofIhe lolUl ftlel heal illputtO the boiler is lhruugh [hc HeW

# g", rcoum inJcclurs 10 he 100alo<1 in (hc lO"l<T 'ccomlary furnacc ahove the lOp rows of cyclone.,. 6gbt 10 lwelve gas rehurn injeClor, would I,e expecled 10 he required llllhis tasc. Se,'en pertent oflhe lolal fuel heal inpulln the boiler lhrough the gas rehul'Il injector, is assumed 10 be supplied for Ihc liJd leoo ga' rehum**all~TO;Jlivcs_** Four In eighl 

### gu, n::b'lm injeclor, <Xl"I<1 

### be assumed ill 

### l'I.G1F'"

cases. Gas rcb"m oplions assume lhat 0 new high-pressure gas pipeline would I,e hro"ght from near 1lismarck, ND approximately twenTY six miles_ The pipelioe diomeler ;s propnniooal to lhe amoum of Iud required lorthe s!",cific alLernatiw, nmging from 24**i,,"h~s** ror eo"venlional gas rebum [0 12 j"ehc> for fuel Jean gas rcbum Cil'CS. A sl"llion g"-S TillJin, wllh new gas trains, consisling ofv"lve,;, melering, and "..Iety shutoll valves for lhe froo! and rear Doiler ror the ga, injector,' s"pply, would he turni'hed and inslolled.

Dllrn, & McDonnell Cl-'l Mmnko," Po""", CO"I'0mllVe, Ino.APPENDlXC2 Capital Co",**b~m",es** NOx BACfAnalysis Srudy



### I 

# I I

, 

# [:

eN Thc capi!:ll costs for conventional gas reburn alternatives were cstimated considering unil capi"'] co.,ts publishcd inpublished lechnicallilCrnlmc. Onc vendor lhal ha.' supplicd nUmerOl.l. domeSlic ulilityboiler gas relmrn sy,le= (GE Encrgy, formerly GE-EER) published $10/kW for gas rcburn in a 2001 technical paper"_ Another SOUrce published a 2005 lcchnical pape," th"t provided a unit**c~pilal** COSl mnge for gas rebum of$151kW to $30IkW. Neither source included a detailed scope desoription nor co.,t hreakdown for engmceTing, cquipmenl, materials, and labor to inslall a !,'llS rebum sy,;lc"Ill.
Silc"spceific needs and challengcs identified for applying conventional gas rcbum to Millon 

### R. Young Stalion, and lack ofdelailed gas reburn projecl scope and cquipmenl de"criptiOIl£ available in published leclmicallilermurc lead,; 10 a much greater degree ofuncertainty with regards 10 an accurale capilal cool estimale for lhis allcmalive. For the purpose" oUhis study, the eslimMcd inslalled capilal cost for a conventional g,.,; rcburn systcm Wilh advanced SOFA on MRYS Unit 1 is cxpecled 10 be approxim"tc1y $9.9M ($38.6fkW), which is abovc thc lop cm! ofthe previously slated ran!,'C, before adding the new underground gas pipeline capital costs. This study assumcd an average unit capacity capital cost factor of $22/kW for conventional 

### 8"" rebillTl, plus the additional co"Ls for the advanced from ofSOFA OVerha.io SOFA (+$L2M or+$>1.6IkW) and the new high-pressurc gas pipeline. This resulLs In a an cstim"tcd installcd oapital co,;! for convenlional/ll's rchum systcm with advanced SOFA, on MRYS Unit

## X of SII.IM ($25_7IkW) plus the new**high-prcssur~** gas pipelinc COSK ConfirmaLion ofthese concept!< and oost e51imatcs rcquire" more detailed equipment design and plant hlyoutthan ha' been performed 

### for the purpose, ofthis BACf analysis_

Fuel lean gas relm'" (without SOFA) eapilal cost estimates wc,c based upon a late 2004 budge"'ry**proposal~'** by a vendor (Fucl Tech) wilh experience in supplying FLGRTM equipment, typically combinc" with an SNCR "y,tern_ Estimatcd capital costs of$3M includc \mdgelluy numbers for thc equipment iosLaHatlon, including in$lallation mmagemenl, material and labur, wilh a --43% price adjustmenl assumed for 257 vs 450 MW fur a fucl1ean gas rehurn sysLcm withoul SOFA On 

### MRY Unit 

### I, not including lhe capital cost for thc gas supply pipeline.**Co~ts** for work outside the vendor's scope, suoh as balance-of-plam addition, plus other indirect cosLs were estimatcclLO**~dd** approximately $0_5M (25% plu, 10% contingency) to thc "djusted vendor's est;mUlcd installed co.,t of$1.7M for theirscope ofsupply. The"e adjustmenL. r"-'ult in a total installed capital cost forFLGR (without SOFA) eslimated 10 be $2.2M plus the capital cost for the**~s** supply pipeline. Adding the incremenlal costs for 11iC advanced from of SOFA o,'CrnO SOfA (-I $4_JM (+$16.6fkW) results in an estirnalcd installed capital cosl for a fuel gas reburn syste"Ill wilh advanced SOFA on MRYS Unit I of$6.6M ($25.7/kW) plus lb.e new high-pressurc 

### gas pipeline co,ts.

MITmko!3 POWCT Cooperal (ve, Ino. C2_5 Durn, & MeDonnellNO, [lACTAn,lysis Sn,dy APPENDIX C1 Capila] Coslll,!iITUllC.<

The capilal COSI**el,lim~** les [or lhc new**high_pressUl'~** undel'ground gas supply pipeline nssumed $7 pel'**in~h** u[ ,li"mclcrper foot oflenglh. This was calculated lu be Hppmximalely $23M [or convenliunal gas reburning anu $11.5M for FLGR1 M. The co"1 analysi, [or each NOx COl\11'01 altemalive involving" IKlL'liouln,· 

## Ion" ufllns**r~hum** "ssmn"d Ih,,1 hOlh boiler>; ;'1 Mlltun R. Young Stalion sclecllhe same**all~m"liv~** Ih,,1 bums nalur"l gas_**Th~rcfore,** Ihc c,lim"tcu cO]lilal eOSIS [01' 

### gos rehurn**allernaliv~<** reflect
a capaoity-based I'fOl'0rllOnal ,hare oflhe gas pipeline cnl'iL,1 cn,L" avmulng uouble--<,ounting. Thi, I'tsull, m "n**eSlimal~d in"~,lku**  e"piwl eu,1 for MRYS Unit I', shure (lflhe ga, p;[,eline lO**b~** $8.1M 

### I for Ih,· conwntional gao rcburn allernulive and $4M for fuel-lean gas rcburn**all~rnajivcs.**
The toLal in,lalled Oal,iLaI cO,L' fol' convenlional go; ",bum (wilh ASOFA) with MRYS UULl l's ohare o[ the lolal eupiwl cost fur 1hc 

### gas supply pipeline eslimaled 10 be $18M ($70.6IkW). The IOlal inslalled c"pirnl costs for FLGRTM (wilh ASOFA) with MRYS Unir I', .,hare oflhc lolul capital cost for thc gus supply pipeline were eSlimaled to be $ IO.IiM (S41 A/k W). Con "rmarion ofIllese concepL, anu cos! eSlimalcs re<ju"cs mOre delailed eqllipment**d~,ib'11** and planl layout lhnn ha<**hee~** performed for Ibe purposc, ufIbi" BACT analysis.



### C.2.3 SNCR 

### Capital Cost Estimate The allcl'l1alive, lhm include seleClive non_Ca!rllylic rc·ductlon sy,lenl, n,.<Ume the u,;e or lla',1 unless noled ulherwi",. The SNCR syslems' preliminary desIgn and estimaled cupil"l eusl, WLTC bHseu upon a 450 MW lib'llile-fire<1 cyclone boiler in" laic 2004 blldgelary proposal' by" ,'enuor (fuel Teeb) wIth experiencc in supplyin!l SNCR equipment. Circulalion, mete, ing, dilulion, conlrol, and injec!ion equipHIOTll i, included. A I**~O,OOO** gallOI1**licld.er~"I"<!** "Imnle" ,t<:cl .,wrage tank WIll hoM Ih<: 50% urea .<ollJl1On (a, delive",u by lruck).**lndi~ldlJal** and multiple nozzle l"ntes wilh mulriple levels ufurea reu!lcnl inj,·elion will 

### b<.**d~"b'1led** "mllm;alnllo oplimize**dlStribulio~** ;lnd aecommo<!nk various boiler lond conditions. E.<timaled capilal 

### co,c, of$4_9 Million intlude budgelary numbers 

### for equipIllL"fI1 insl" 1I"ll0n, including in'l,lIalion mnnagemcnl, malmnl and labor assumed lor a SNCR s}slcm applied 10

" 450 MW boiler. Costs [or work outside Ihe Vl"flUor'S scope, such ;'s olliduorrC;lgelll ,Iorage lank and building enclosureiequirment foul1dalions and containmL"fII, ;llld halance-olCpbnt additions plus other indireci eOSl' were estimaled 10 add**appro~jrnmcly** $1.9 Million (25% plus 10% cOlltingency) 10 Ihe venuor',**~olimMed** ins!ullerl CO,l for Ihcir scopc ofslIpply_ This results In ;In e,lim"leu lolal capital CO,1 for SNCll (wilhool SOFA) of$6.8M for a 450 MW lignile.fired cyclone boiler.

Hum, & MeDonTIelJ C2_(' M;nnko'a Pnwer Coope"'Livo. lno.APPENDlXC2 Capital Cos, Es,in"lc, NUx BACTAnaly,i, Sludy



# Ig III

, Applying these adjustmffil_ to 257 

### MW boiler, estimated direct capital costs of$2.800,000, plus $1,000,000 for indirect cOSlS yields a totol inswllcd capital cost for applying SNCR to 

### MRY Stalion Unit 1 ofapproximotcly $3,8]6,000 ($J4.9fkW)_



### C2.5 Layered Technology Capital Cost Eslimates Capita

### Icosts 

### wlTC gcncm

### Ily e.'**~'nw** l<:<l ",,'ed upo n
. .,,;mple arithmelic addition ofindividual unit output capital cost facio," for**combin~tions** ofavailable 

### NOx reduction tcchnologies, such uS SNCR with ASOF

### A. An advanced foml ofocparated overfire air system includcd lhe ligmle-firc<l cyclone boiler equipment changc:; within the estirn"tcu unil capital cm;1 [actors.
Adding the advanccd SOT'A capit.ul cost of$4.3 Million to thc prt:vious estimated inst.alled capilul CO,l of $3.8 Million yields a total cslimated installed capit"1 cost of$8.113 Million ($31.6IkW) for th. SNCR with ASOFA ullcmalive 

### for Ml{YS 

### Unil L

As prevIOusly disGu"Scd, Lignite (coal) rebum 

### (CR) was 

### us.sumed to be combincd with advanced SOFA nnd a COHPAC addition**consid~.,.ed** necessary to limit the expeclcd negative impact on opacity from ibis option. Thc inslallcd capital CO"t oflhc COIlPAC addition was estimalcd to he $23,561,000 for MRY Stalion Unit 

### L When the COHl'AC 

### addition was combi"ed with tbe Lignitc Reburn and ASOFA "llemati'lcs, Ihe resulting lOlal estimaled capital cosis wcre $46,656,000 

### for WtYS 

### UnIt I ($89.9 

### + $91.7**~SJ8l.5fkW)_**

Minnkol, Power Cooperalive, 

### Inc. C2-7 

### Burns & 

### McDonnellAPPENDJXO O&M**C<>stE'~m3leS** NO"BACT Analysis Sludy

'. 

## iff<' 0



# ,

C"

0 

## ..

## , C.3 Operating and Maintenance Cost Estimates for MRY Station NOx Control An evaluation was perfonned to**<1~lcrrnine** lhe esLim"tc-d operating and maintenancc co,t impacts of inst<llling end conlinuomly operating various fC'llsib1e 

### NO, control lechnolo!o,'ies on Millon 

### R. Young StaLion Unil I. These wcre estimatcd to bc in addition 10 cxisting O&M costs to opcrule and tlliIint<tin thc MRY Station cquipment

The expected loss ofelectrioal power sales from Ihc operation ofthc specific NOxcontrol alternativc was included as an nnnualized cost, assuming $35 per megawatl-hour. This was detcrrninffi to include estimalcs for:

•**Re<!u~tion** in annual unit output due 10 an expeeted negalive reliability (i.e. uptime uvuilability) impact for eachalternative. This generulion rffiuction was calculated by multiplying the
esijmated nddilional numbcr>; ofoutage hoursperyearby the UVerllge rmming plant capacity factor for that specifio alternative, multiplied by the historic 12-month average unit grOSS elCClrical pow"r OUlput 

### (MWJ determined during the same period**~s** the highest l2-monlh rolling sununalion NOx pounds. Net additional auxiliary clcclric powerdem"nd for lhe added conIro 

### I equipmcnt loreaoh specific alternative boscd on assumptions for gross horsqlOwer, rlus additional powerdemand for exisling f"ns cau<ed by l1uc ga, pressure drOp (COIl?AC for u<lditionaJ I'M colleelion oapacity), with adjuslmcm for expected reductions in powc, demand (such as a decre""" in existing coal crusher and feeder eleottic dem"nd for lhe pl,Jverizc<l coal rebum cJse). The averagc wnning plant capacity factor for eucb altenlative, which 'nay also include all expc"Clcd negative impaol on the unit capacity lrom oper"tion ofthe technology. This "","IImCS that the control teehniquc limiL' the gross elcctrical power outputof

### the Unit (such as causing In inorease in flue gas flow) such lhat the firing rutc ofthe hoiler cannot be JlliIintained or raised to compensate for thc load impact Example, are lowerboilcr lhennal cfficiency (highcr Unil heat rate) when firing natural gas (due to highc'rmoisture contenl of1he flue 

### g""s).

For the SNCR allernative thai involves a chc-mical reagent injected for NOx eonlrol, such "S urea, the annual reagenl consumplion basc<1 on an assumed actual stoiChiometric ralio (ASR) ofmoles of equivalcnt 

### NH, injected per mole ofuncontrol1ffi 

### NOx emission estimaled 

### "I thepoinlofinjection, convertedlO a

# Illil-'"' rale (lb>Jhr) by multiplying by the estimated annual number ofhours ofoperation and thc eslimated NOx reduclion fraction, and lhen multiplied by unil reagentcost (for a speoifie inletNOx concentration, emission reduction percc"Tllagc and ammonia slip level).

Minnkola PowerCOOl'CRllil'e, hlC. Burns & McDonnellNOx DACrAnal)"'i" Sludy APPENDIX ('3 o&M COSI Eslimalc.,

Geller.l anm,"1 mJintenJnce COSIS were assumed to be 1.5 perce", ofthe e3limaled inSlalled capi[al cost [or each allernalive, exeepl [or [he co"1 conveying and grmdmg e'l"ipmcnl poriinn ofIhc coal reburn alLem"livc, which was a"ullled [0 be 3 pcrecrtL The periodic hag**replac~ment** cosls ;ml1 other COIJl'AC sys[cm mainLe""Tltc**~0"1,** were es[imJted 10 he .pproximalely 5.J% o[**(h~ ms~,Jled**  capllal cost o[**Ih~** additlOn,,1 p"rlleula[e**lllatl~1'** oolkclion cquiprnenl.
Addilion,,] opcmling labor coms**d'I'"~I]y** allribulable to**ea~h** alLernmive were a<sumeu h> be zero for all al[em"livc,.

Olheroperating**~u,l,** include:

• Reagenl dilulion waleI' for Ihose**all~ma[ives** lhal involve a chemieal reagenl inj"Clcd [or NOx conlrol, !yplcJlly fOllr**lim~s** Ihe "mount orurea c",,"umplion (aosumes URa is a 5[)o/, solulion as delivered and is mjccll-u "$ a 10% ,oJmion); this fonows EPA OAQI'S convention'.

• Heat I'equired for urea, eagem .'torage, for**[ho~c ~lt"mJlives**  [hat involve a ohemlc"1 reagenl**inje~lcd** for NOx COL\lrol; lhe ,ourec o[heat IS a.sullled lO he**a""ili~ry** ckclric"l power, hUl eou]d be auxiliary ."e'm (lkpcnding on**he~t** .,ourcc avail.bility "",I planl preference).

• AddiIion.1 eool consumplion 101' lhose ul[emutivcs thai involve a chemical reagenl mjccled for NO" conlrol 10 compens"t" for the heal ofvJporization ofIlle reagenl di1<ll;on waler; This follows EPA OAQPS convention', hon if> not accep[c<1 pmcl;cc by an expenenced SNCtt vendor (Fuel Tech) who claims lhal the hcul prouuccd fl'OJll the exo[hermic l'eoeLion ofurea and NO, i, approximalely equ3110 the heal ,c<juircu 10 evapora[e lhe dilu[ion waleL For [he purpo,",s oflhis ,111.11', [his additional "0;,1 consllmp[ion has heen include,i in ti,e nnnu,,1 O&M co.'L'_

The sum ofIhe eslimaled annu,l1 o&M costs wa, "'ulliplied by Ihc O&M kveliza[ion :act,," (**1.2~** 873) f,n each alIen,allve [0 yield leveh7.ed [lllol nnn,,"1 O&M cosl,.



### C.3.1 Separaled Overfire Air O&M Cosl Estimate Operalion ofSOFA is expeclcd to add a small nmount ofO&M eosl, primarilyeleoIrieilY consumed hy the conventional SOFA damper electl'io drivo aolualor and airl1mv measuring system lransnlitler on each POlt. Using (he e""ling forced drali, im1ueed draft, and flue gas n,eirclllulion f;ms is not exrected 10 change**Ih~** overall amount off"n horsepowe, d"'n"nd to k**~lIpplied** by [ho.<e fans' eleclnc molol'a. MamlO'anc. ofthe new overfire ",I' I,orts 

### 'lOU relocalc<1lib'lli[e d,ying 'y'lem venl ports is included,

BUlliS & M,Donnell (,]_2 Mlmoko\a PowerO>"ptrdllvc, Inc.APPENDIXC] O&M CostE,lim,lo, NOx BACTAnalysis Srudy



### ,- .**~.** as.-'mmed 10 be 1.5 percent oflhe installed capital 0001. This is included in eve!)' oOIllrol allemative's cstimaled O&M cost

SOFA is not expeoled 10 signiIjcanliy reduoe unit reliability and availability 10 generale electrioal power, assuming consistent combu"tion and "Onlinuous slag lopping under substoichiomelric air/fuel opel1lling oomJilions for MRYS boilers can be roulineiy eslablished. A Unit a""ilabiJilyreduction of2.2% (188 hours peryc"r), forM.R. Young Statiun Unit I was aB"umcd, which nllows for forced or exlcmkd scheduled boileroulages lhal may result from problemalic cyclone slag tapping operalional condilions encountered during "UbSlOichiometric cyclone opcnllion with SOFA. The expcclooloss ofelectrioal power ,",kB from the reduolion in nnnual electrioal powcr Olllpot due to a decrease in e>:pcclcd Unit avaiiabiJily from ASOFA operation is included in every control ullcrnalive's estirnaled O&M cos!.

Boiler furnace walcrwall tuhe mainlenance nmy inerea.", slightly as a resull ofmOre fireside corrosion due 10 substoichiometric cyclone operation wilh SOFA. TI,ere may be "orne**ch~ngcs** in the degrndalion rale ofthc boiler's furna""**w"I~'rWnll** tubes resuHing from c:posure ofmore area ofthc fumnee walls 10 sEghlly air-sl"rvcd conditions during SOFA operation. Such condilions can promole corrosiou from "ulfur compound" in Ihe [urnace gaBes being crealed above the cyclones and belowthe SOFA injeclion porl>;. Due lo lherelatively moderate amounls of"ulfurcontenl in the lignile, modes' amount orair- .'laging oflhe e)lisling cycloncs during SOl'A operalion, and lhe potenlial use ofrecirculated flue 

### gas along lhe lower furnace walls, the e)lpec!cd change in corrosion rale ofthe boiler tubes should b. minor. This degradmion is e)lpected to oc:cur**OV~T m~ny**  years ofoperalion, and nonnally reqoires periodic replaccmenl ofthe delcriomLed seclions ofboiler fumnce wale,w.ll tubes 10 avoid forced olltages to repair lube leaks orfailed "eelions. The additional 00"l>; assOCialed wilh potenlial change in lhe**frcqu~'ney** offurnace wall!ube failures and ch"ngcoulS nre dirficuH 10 oslinmte, and have not been quanlified.



### C.3.2 Reburn O&M Cost Estimales The allcmalives lhal includc a new ooal rebum syslcru ","orne Ihe use ofnew equipmenl forprcpariug lhe rcbum fuel to Tl.l'laee 25% ofthe MRY Stalion Unit I hoiJer's lotal fuel hCalinput. Two additional lignile silos, wilh coal keders and fjne"grind pulverizers followed by dynamic classifier(s), are assumed lo be localed in a new separdtc boilding or powerhouse enclosure. Booster [an(s) addilion wos included because lhe existing forced draft fans were assumed 10be incapahle supplying the nddilion.l amount of primary air to lhe fine-griud pulverizers and dynamic cl","ifier{s) for processing and convcying lhc rcbllm fuel. Using lhe exisling forced drall, induced draft, Jnd flue

# g"" recirculation fans iB not expecled

Minnkol. Power**Coopera!i~e,** Inc. C3-3 Burns & McDonnellNOx IlACT Analysis Sn,dy APPENDlXCJ O&M Cos! E"irno.'c' lo**~,,,'Ilificanlly** change Ihe overall amounl offan ho"epower demand 10 he ,upplied by Ihusc fam;' electric motom. The expc'Cled loss ofelech'jcall>ower ,ale, from Ihe addillOnal auxiliary electric power demand for Ihe rehum milling equipment ["rom an e,limnle,1 0.6% (1.5 MW) reduclion in nel O"lpul was included a.' a cost, ",,"ming$35 per megawatl"hour for MRY S1a1ion Uml 1. Electrical rowe, oonsumed by Ihe inercased load on boiler lims 10 OVCTcomc Ihe higher fluc ga, .'ysIem pre,,,rre drop, pIllS the COllI'AC parrioula!e colkcllon syslem suppo,1 equipmenl W'S eslimaln] 10 he a 1.2% (3.2 MW) ,,'{luelion in net oulput for llnit I.

MainlcnaLlce or'lhe sepllr"le rcbum coal mjecrors, tiJe] ami pnmary air piping, and rehurn fuel millmg equipme", i, e"peeled lo 

### be similar In Ihc expenscs associalcd wIth typioal pHIveri'lcd coal burne". 'me e,limllle,l,uldilional annual**mai"l~n"ncc** cosls for a new miclOnized cOlli [Cburn sy'lemwas assumed lo bc 

### 3.0 percenl oflhe iLlslalled**c~pllal** cost, 

### or roughly**.~69J,OOO** p'" ycar, for

### MRY Stalion Unit I, Thc estimaled additional annual mllmlenance cosL, (inflalinn adjLL,Led [rom 2002 to 2006 $) [or Ihe CORPAC 'y,Lem was apl'ro"imulcly $1,223,000 tor MRYS Unil I.**Boil~T** fumace waLerwall lube and ,uperneulerfrehealer lube mallllenancc may increase slightly as a resulL ofmore erosion due 10 increa"ed parl,culale em,ssions or [oHling by flyash depo5lts re.,ulting from 00111 [Cbum operalion wilh 

### ASOI'A. The addilion.l cnsl, assucialed willi pntenlial change in the frequency ofboiler rube fallurcs lmu**changcOI1I~** urc difilcult lo eSlimate, and h"ve Jwl bccn quantified.

The eslimaled impacl' 

### on 0p","lion and lll.limenance 

### en", lor 11lc cu"l rcbulll altemall

..ell.aIineh

..lc a
new pulverized 

### or micrunized coal rebun, .'ySlem orc approx,male. The seve" (Unil 1) exi'llIlg coal cru,he,.,; f'" preparing Ihc mai" (cyclone) luel fTnelion will have slighlly lower elcclrical dcmand. This**w~,** e,llm"IL'{l us -0.26 MW (-(t I%) for MRYS Umt I. Addilion ofnew ekeiriclllloa<ls for Lbe micronized coall'repamtion e'luipmenllo the existing planl faeihlJcs will be required. For the pUlpO,",S ofIh" preliminary sludy, il is ",,"med Ihat addil,o".1 plonl auxiliary clecllicnl [lower will he llv"ilable for powering Ihc no'v pldvmzerslcla", fLers and rclal,·u ncw co"l [Cbum equipmenl, bul Ihi, ha' not been confinned.

Coal Rehum wilh ASOFA is nol exp-ected to "gnificlllllly rcduec Wlit reliabilily "nu availability to g'cncrale elcciricall>ower, a""uming' eunsislenl comhuslion and oontinuous slag tapping under substoichiometric air/fuel opernling conditions for MRYS boiler' can be roulinely eSlablishe,!. A Unit a"allability reduclion of3.7% 

### (316 hITJyr), lor 

### M.R. Young Slalion Unit 

### I wns a"umcll, which aHow.' Jor 

### rorcr:,l OT**c~lenue<l** scheduled hoilcr o\llagcs Ihat may**,.~.,,,llirom** problematic operalionnl eondiliuru; eneuuntered during coal rebum operalion wilh ASOFA. This**r~ullction** in annual e1eclrical power outpul

Burn' & McDollnell CJA MinnkOLa Po""r Coopcrali,'e, Inc.APPEND1XC3 O&M Cosl Eslimalc, NOx BACT Analysis Study

due to a decrease in expected Unitnvailability i, included in lhe coal Teburn control ahemalive's e,timale<! O&M cost

A Running Plant**Capa~ily** Factorreduc!ion of0.5% ofannual gross electrical oUlput was assumed for Ihe coal rcbum allemalive. This would resull 

### in an eSlimate<! 1.2 

### MW average load**dl-cr~-ase** forM.R. Young Sialion Unil I. This expecled lo1.S ofeleclrieal power sales from lhercduclion in nel outpul due to Ibis planl eapacily impaot was induded in the estimaled annual O&M co,ls.

Convemional and fud-lean**gu~** TCbum oplions wm involve higher operaling**coSI~** compare<! wilh lhe exisling operalion ofM.R. Young Slalion.**N~luml** 

### gas supply**w~s** assumed lo 

### be**~vailuble** near Bismarck, ND, butthis has nol been confirmed. Tbc eSlimaled unit cosl ofthis natural gas was """,,limed 10 avernge $7.98/million Btu on a leveli7.ed annual coslbasis, wilh a "credil" of$0.71 pe:rmmlJlu for avoided cosl ofconsumplion orlignile coal reduced by lhe nalural gus heat input. The e.,limaled annual cos! ofnaturnl gas for lhe eonvenlional g;ls reburning aHemalive applied to MRYS Uni, l.is approxim" leJy $29.7M 

### peryear. Tbe**eslim~led an~u~**  

### I cost ofnatural g"-' for lhe FLGR"" allcmu!ive applied 10 MRYS**U~jt** 

### I is approxi""'lely $12.JM peryear.

The new gas rebum injeelom, stalion gus main and injector gas trains would add a minor amouot of expense 10 curreot maintenance reqoiremenls. ussumcd 10 be 15 percenl ofthe inslalled c.pilal eOSI. Maintenanoe ofSeparaled overfire airnozzles is expeele<! 10 be similar to lhe exren""s assoeialed wilh Unit Ts existing flue gas recirculalioo porK



### C.J.J SNCR O&M Cost Estimate The allemative., lhal include sdective**non--cal~lytic** reduction syslems will involve higheroperaling oosts compared with!hc cxiSling operation ofMRY Stalion Unit.I. Ureureagen' supply was oonfinned 10 be available regionally. Thc estimated unil COSI oflhis 50% aqueous urea solulion Wll.'I assumed to average approximately $379/(on delivered (2006$). Consumplion "furea reagenl 

### fOl SNCR wilh ASOFA 

### was based upon preliminary numbers allowing for a boilerflue gas nil ammooia slip or

### 5 ppmvd. These**W~Te** CSlimaled as approximalely 200 gph for SNCR when applied 10 MRY Stalion Unit I wilh ASOFA.

New eleetricnlloads a,C required for high flow urea circulalion, in-line and storage mnk healing, waler dilulion, and reagenl melering equipnlent. These auxiliary electrical demands and reagenl dilulio'n walcr usugc were calculaled based upon equalions**publish~X1** in 

### EPA Office ofAjr Quality Planning and

Minnkol. PowerCooperative, Inc. Bum., & MoDonnell**NO~** BACT ATI,ly,i, Siudy APPENDIX C3 O&M CTI<T F'limOies
Sland.nJs (OAQPS) publication EPA/452/B..Q2-00I, Seclion 4.2, NOx Control.,

- NOx l'osl-Combmlion, Ch"pl<:r 1 - Selective Non-Cal,lylic Oxid"tion'. Compres.,ed air fnr re"gent "Iomiz"lion "l<llancc purgiLlg ,nd oooling, us well "s multiple n07,?Jc lancc wnlcrcooling**ar~** mJdilionul dern"nds (In Ihe exisling plant f,cililits.**Th~~e** p(Jwerhou,e buildi,,?, scrvicc**,uppli~,** wen:: "s,llmed In 

### be ,w"ll"bJe, bul this lon, 1101 bcen confirmed. The**n~w** lire" reagent injection nozzle lance" rengenl pUl11pS, dilution w"tcr pumps, and dlS!IJbulion pipinWvalve train" would ,odd a minor**~mo""1** of**~xpen,",** to c"rrcnt m"inlen"noe**requirerneTl~,** ","umed 10 

### be 1.5 percenl ofIhe inslalled capi!al cost.

SNCR with ASOl'A i, nol**cxp~eled** lo signJticnnlly reducc unit rdi"bilily and**a~n,** ];lblhly 10 generole deco·ical p<>wcr, ","uming urea injection doc, not impact the abilily to mainl;!in consistent comhllSliun "Jld tnJltinuuu' ,lag tappmg under sub,t",chlOl11e,ric air/tuel operating con,lilions for MRYS bUlk". A Unil "v"il"bilily reductioLl of3_2% (273 hrs/)'I), for M_R. Young SLalinn Unit 1 wo., assumt,l, 'vhich "lluws for forced or extendcd schcduled boiler oUlages Ih'l may resull from problemnlic up<Tlllional conditions encounlL'n::d dunng SNCR-re]alcd up<:l1liion wilh ASOFA. Thi, reduclion 

### in ",mu.1 eleclric,,1 powcr OUlp,,1 due to a decrea,e in expcclcd Unit availobilily i, induded in Ihe Ihese mnlro] oltcnlll!ive:s'**~"linllll~J** O&M coots.

A Running Pl.nl Capac;ly Faclor reduolion of0.15% ofannual gro" electriclli olllpllt wa, a"umcd fur the SNCR wllh ASUFA alternative. This would re,ult in all estimated 0_37 MW aye, age Inad dc""rc",", [orM,It. Young S",tion llnil I. This ""peeled In" "r·elcclncal power&llcs from ll,c n"{luclioll in net output due to lhis plnni c"p"cily impact was mcludcd in lhe eslimalcd llnnu,l O&M cosI,.



### C.3.4 Layered Technology O&M 

### Cost Estimates Operaling and m"i(Jlenance cost, for combin"lions ofavailable NOx reducli"n lechnologie, wen:: cOlimal",1 b",cdupon simple orilhmclic addilion ofindividual cosl e.<timalcs. SNCR \Va_ cumbmcd wlth advanoed SOl'A, as previously shown_ Pulvcnzcd "oul rebum was assumed 10 

### be combined will> advanced SOFA (lmd a COHI'AC addition [orI'M control). The auxiliary ckcmoal demands and rcagenl dilulion \VUler u,ugc for SNCR wilh ASOFA were calculaled ba,ed UpOLl ""'I"alions puhli,htd in EPA Offioe ofAir Quality Plnnning "nJ Slandards (OAQPS) public"lion EI'N452iB_OZ--OOI. Section 4-2, NUx Conlrols

- NOx Pusi-Combuslion, Ch"plcr I _Sdecllve NOll-CalalYlie Oxidation'.

Bum, & Mc[)o'lilell C3-6 Mi"okOla PowerCoopetali"e. Inc.APPENDlXeJ O&M Co,t E,liTIllllos NOx BACr Analysis Study


### C.3.5 Summary of O&M Costs Estimates for MRY Station NOx Control Thc rcsults ofthis evalualion for estimated vnliable operaling and muinlcmncc co,ts for lhe individual 

### NOx conlrnl alternative., are summarized in lhis section. Thc cxpected**redu~tiOl\s** 

### in Unit**~vailabi1ily** 

### (uptime) and capacity are imludcd in 

### Table, C.3-1 through 

### C3-4 for MRYS 

### Unil I. 

### Tahles 

### C3-5 and 

### C-3-6 for MRYS 

### Unil 1 

### include lhe estimaled ureareng,ent and dilulion waler lL';age 

### rates and COSIS 

### for the JltLTIllllivcs thai 

### involve SNCR wiLh ASOFANOx "ontrol**te~hnologi"".** 

### TABLE C.3-1

- Expected Availability Reductions for MRY Unit 1 NO" Controls

I':slimaled Annu.1 Ave<3ge Unit**OpeT3lin~** Time
Unit Unit Unit Operating**Onl~ge** Operaling Unit 

### r '**T~~4,** Time Redn<linn', 

# ::" All.' NO"Cm.trnl Technique Avail3bility' h.' r 

# . , hrsl r



# , SNCR wI ASOFA 0_942 &255 

# '"' m 0 Ga, Robnrn 

### wi ASOFA 0.952 8340 

# "" 

# ,

# .. , Cool Rcburn 

### wIASOFA 0.937 8212 

# ''" '" , FLGR wI ASOFA 0.952 8340 

# "" 

# '"" A Advanoed SOFA (ASOFA) 0.952 8340 

# "" ,

# ..**B,,-,eli~"** 0.973 8528 

## m 

# " I Allom''''e**n",~~er** has boen prevlou,ly as"gned r,on, I

.." renw",1 to h'gh""l ,emn••l pcrc<:111'Ce. 2

-**12·monL~ ~"ohnc**  ,v,ilat.ilily i' as'umed ,I 97J pc""nl. Th"" "Iu" 'eflocl <Sli"""cd ,mo""l' or"'glIlivo ,di.oiiiLy imvoel expeclod [rom the implem"""tion orLho indi'>'iduol NO. oontrol lcchn;qu". l

_ Annu,l operaLinB Lime is ,"n",1 avo"'go ,,,,,Habilily muhiphcd by 8760 h,,;lyr orvo"'ibl< uplime:. 4

- Annu,1 oul'gl: limo i, S76l1 h><lyr**rn.~';hle** opo"l;ng Ii"'" m;L1us esLimaLed annu.1 o[>OraLing lime. 5

_ Mnu,1 oporOling Lime mI"c,iou**rC5ullin~** [rom lIlo implcmcn'.lion ortoe ,ndi,idu,1 NO, eO"',ollcehni4uo i, Ihe <Ilff"ono<o """,oen Lho baseline ""d expocted allnual O"",g< Lm",s.

Minnkol. Power 

### Cooperalive, Inc. C3-7 Bums & 

### MoDonnellNOx EAC[ Analysis Shldy APPENDlXCJ O&M CO,1**E.>liIllal~** 

### TABLE 

### C.3-2

- Expected Capacity Reductions for MRY 

### Unit 1 NOx Controls

() B P Y!?l g pc g (2) 12_mo,"h h."I;"e n'nn;"g plonl cop,e;'y f""OT is "-'Surnoo al % (,

## p'''''.'''- TIle" ""h", ren,e' «'''""loo "IIlnun" of ",",,"ivo Toliab;lily irnpa" expecLed r,"m 'hc lmpl"""n'''li",, "flhe iotlivid",1 NOx contrnl '''h";'I''o, 0)

- Annual dowie,'Y**Ben"~L,o"** ,.duel10" lS "no,,1 oper'ling 'imeroon"io1\ mnl'iplioo by 'h< .nonal nIJmins plan' c"pll0ily lacL",**,,,,,llin~** from Ih, iml'lem",LaL,on "f 'he iLldivldu,1 NOx ,onl<ol ted"';'I'" mullil'lied by Joe 12-mon,h ,v,,"go gross OULpUL "f244.4 MW_ (4)

_Annual clceL""Ly go""aL;,m ,,<Iud;on coS! ;, 'he "0"",,1 decLric")" gcnerolLon redu"io" (kW-hTs/;T) rosulLJn£ r,,'m Lil, Lrnpl'"'e"',,L,,,n "noe indiv;dual NO, "'''''01 Lechniquo mul"plled lly lI,e ",e"''''''',,1 ",Iue orel,w;cily !:Onc,.",", .ssumoo Lo be S3,_UUlMW-I,,_ All <oS! f,gu," ,,'**~1li)6** <1"11",,, Esl'IIlatcd Annual Aver.'ge Uuil Eleel.ioall'owor Generalinn lIeduction fTORl'()I'OTaline Time R.dueli"n Unit Unil**GeDer~l[on** Unit G,"e,ali"n All. Running Planl Red"olioll'" Rcdllct,on C"'ll'), 

### L.bcl")**NO~** Conlrol Techniqne Capadtv Faclor") kW-ln-sivr**1000.~lyr** C SNCR wi ASOFA 0_965 67,660,606**2.36~** D G., Rcbum wi ASOFA 0.957 16,120,681 1.614 C Coal Rcburn wi ASOFA 0.%1 /7,958,350 2,729 

# , FLGR wi ASOFA 0_962 46,400,200 1,621 A Advanced SOFA (ASOI'A) 0_966**4(,,5~6,546** 1,631 Boseli"" 0_966 

# " 

# " , AIL,rn"i"" de.,i naLio" ha< been rev,,"u,1**,,-~<i,·** cd fTOIll k,SI Tcrno"al '0 hi host n""o"l rocnLo e_

Burm & McDonnell 0-8 Minnk"lo Power COupLTILlive, I"c_APPENDIX 0 O&M CO'IEslimare,s NOx BACf Analy.,i., Siudy


### TABLE C.3-3

_ Expected Auxiliary Electrical Power Demand Changes for MRY Unit 1 NO. 

### Controls

() g p y g g p g 

## m- The IIfCNOx equip,",,"' S""'" auxiliary elwrieol powerd=aTId of.nemaLive, i5 lho sum orlndividual lechnolosi" combined by simple add;lion. Ac'ual 

### PO"'''' demand, may dilTcrfrom lhi,**~ti,** '" po5Hive or**ue~'live** 'YlH:rgiSfio elToolsCoal robum i"d<Jd" 1,507 kW rOT feod p'''l',,,,'ion .nd eO"""ying 'quipmeoL d<,",md plu,**3,15~** kW for the COHI'AC 'ystem addition for PM CO""ol. (J)

_ne APC NOx equipme"1 au'ili.ry eleonie,l powerdemand cred;1 ofco,l "bum ,ltom"li", i, Ihe <>li""'too**r~"1L** or lower "yolo"e 0001 prcparaTion and f"

....lorpowo,-**de"",n~ ~ue**  Lo lowerbo,l" cyclon' 0001 equipmcoL loading. A"u,l**PQ'''_~** d"m;od, may differ Iinm Lhi, due

# '0 =U"'CY o[eSfi""'te, [or

...,onled .mounl o[o!","'Ling hO"'j>OWorredu"ion_ (4)

_ fl-,,-IOl,1 n, [auxiliary cb:lr1-e,) powerd""'and i' Lhe_,um orrhc gmss dem'"" .udcredit (5)

- nc ""nu,l thange in APC NO, "'luipmrnt "u,iT;.<y <1<eI,ic.1 power**dcman~** deeTdcity u"'ga io kW·h,.lyr for thesc ,IL"""li"" i' Ihe 001 powcrdcm,"d muIL;plicd by 'he es,imaLoo an"".1 opcroti"g rime and**mnni"~** planL taraClly faotor which

# «"""" the adjostmcn' for aoy c'peoLed rdi"bil;'y and e:ll"oi'y Im!",'"' rrom 'he imrl,m"HaLion o[rhc**oonrroll""hni~",_** (('J

- '[he ,nm,,1 ,h,,"se in APC NOK equipment aoxil"ry elecLric.1

...."'" deRland clc-cl,iciIY CO" i, 'he au""al d,.nge in kW_h,s1yr [orIh"", allem,Ii"'''**,e,oILin~** [(Om ,1,0 iml'l,mC"Latioo ofIh< individual NO, '"nlrollcohoi'IUO mfliliplied by Lh, inOTcmcot,1 v,lue or"u,ili.<y elec'rioiry gelfe,.tio,,- ,ssflm<d ro he SJ5.00IMW·hr. All cost figmcs i" 2006**<loll",.~** E.lima",d Anm'al Avn.geAPC**NO~** E'luipmenl AnIili

....... Eledrical PowerDemand "od Usaee
Gross Tolal Net**Pow~r** rower Usage 

## M'. Demand 1'1 C,edil'" I)emaud'" U,age'" Co,t'" • L.bel'"**NO~** Control Techllique 

# "" 'W 'W kW_brsl r 100051 r 

# , SNCR 

### wi ASOFA 73. I 0 73.1 532,411 

# " D 

# G., Reborn 

### wIASOFA 

# , m (132) (1,054,J43) (J7) C Co.1 Rebllrn 

### wi ASOFA 4,6M 

# '" 4,405 JJ,905,082 1,217 B FLGR 

### wi ASOFA 

# , " (72) (578,744) (20) A AdvaneedSOFA (ASOFA) 

# , 0 

# , B.05S 0.' 

# , AI'<:mati,'< <I",i n"ioll "'-' boen fCviou,1 

# -, n,d ITom Ie"", "moval

# '0 hi h.,,;1 ""."vol ..,-e,n!a 

# ,

MiTmkOfa PowerCooperntivc, Inc. 0·9 Durn' & MeDon""llNOx DACT An"lysis Study APPENDIXeJ O&M COSl Eshm.le, 

### TABLE G,3-4

- Expected Auxiliary Electrical Power Demand and Generation Reduction Cost Changes for MRY Unit 1 NOx Controls

() gn p y gig (2)

_ The ann",I chongo 1Il AI'C NO, equ'l'monl ,,,.iIimy dccLr;ea! I'''"or<lemaml dOdr;e;Ly**"~ge** io kW_I",Jyrfor Lhcse aloc,naLi"" " 

### U" "eO**r"W'~** ,Iom,nd muIllplied by Lho o'lim"oo "on".1 o!'Cr"<mg Lime ,od 

### '""";Og plan' edpa6ty f,eLor whi,h reDeelS Ih, adju"",e," for "ny "",!'C,oed r<liaLiH'y aod capaciLyimpact< f",m 'he impIemcnLaLron ofLoe eon([ol**Lcch";~"c.** (J)

_ Ano",1 elw""Ly s,""aL"", ",I""ion is annoal**0I""aL;n~** L,merOOl1e,ion m"ILipli,,j bylhe ,0nu,1 "mn;"g pI,nL ""J"e,'Y i"'lo, """I'ing from the implcme,"al"'" "f,he ind,vidual NOx eonLroI Lechmq"c ",,,IL'I'I,,,) b)' Ole 12_ monLh oYe'age gross OULruL "f244.4 MW. (4)

_ rile 'oLaI "'0;' ,lcc1r;",I**puw'~** g,ncr,llion change ;< 'he '"m ofLho ,nLloal ChOllgC in I\PCNO, equipn"nl au,;I;.,y elee'"e,,1 powor dem,nd elrerri,")'**u",~e** pi", 'ho .nn",1 clcc'nciLy generalion rodu"i"n**rc'"I1;I1~** from lho ;mpIemen"'L1DO ofthe indivJduol

### NO, """',,,1 teehnique. (5)

_ ·1 he loLal ",,;l do"",;,,,,II")"'«**8e"c~"ion** ehonge co"

# L' Ihe lU',1 gencrallon ,honge**(kw·hrsl)~)** ",,,lripIicd b,' 'he ;ne,omel1l,,1 ",Iuc ofe!C"';c;Ly gco""uall,**a~,umc.:r** Lo be SJS.OlliMW-hJ 1\11 cast Jigu'".1 J" 2006doll"". K,limaled ,\nnn,,1 Cl,auge III Unil Gellerallun Due lu APC N(b Equipmonl Aux'li.",**P"",~r LltOlrj~Ily**  DelJ,and "lid Generalinn Rtdutlioll 

### >eC Total U"il ,."lal Unil Fle<lrkal Unil**~]eelr'c~1** P"wer EIeclrical Power

Po

....er GCllerati"n Gm..-allon (;eoe,-alion All. U<age'" Reducllou'"**Chau~e''"** Chaoge ('osl'" Lahel"l**NO~** Conlrol Teehlliq"e kW hrslyr kW_h.-.lvr kW.bnJ)T IOOOSI)'r C SNCR wi ASOFA 582,41 I 67,66U,606 63,2<l3,UI7 2,3R9 D (;"' Rcburn wi ASOFA (1,054)43) 46,120,631 45,066,333 1,577 

### C euaI Robum wi ASOFA 11,9U5,082 77,953,350 39,863,432 3,946 D FLGR wi ASOFA (578,744) 46,400,200 45,321,456 1,604 

# , Advonced SOFA (ASOFA) 8,058 46,5R6,546 46.594,605 1,631 

# , AHem.,ived"", "ion h" 

## ocen ",.io"-,I "-,,; nc.:r from leo" removal

# '0 hJ h,,, '0010",,1 '0"'111" 

# ,

Burns & McDonnell eJ-lO MinnkOlO Powo,**('OOpc~"liyc,** Ino.APPENDIX 0 O&M Cost E,tim.te, NOx BACTAnalysis Study


### TABLE 

### C.3-5

_ Expected NOx Reagent Usage and Cost Estimates for MRY Unit 1 NOx Controls



## () s PYS" g i>CS 0)

- All COstfigure, in <006 dollar,,- (3)

- Rc,geoH diiuLion ,",,",ru,age """""',, po,"!>le waleris ,ddoo 10 """He, 10% "rcaconoentrIli;on (4 pons w"cr iu 1 part "rca solmion 3150% con,enL""ioo) I"ior '0 injoetion. D,luiion ",aLerun;[ """ a<.,u"",d 10 bn SUHlpcr**,h~u,and gall~",.** **NO~** Reduction NOxRcdoetion Reagent Dilulion Reagenl Ur

..**U,~ge(l)** Wain Usoge'"
Alt.**L~bel,n** NOx Conlrol Tecbnique Jbsll,r tonslyr

### JOOO~hc JOOO 

# ."**JOOO~h**



# , SNCR wi ASOFA 1,894 

### ',,," 2,861 7,232 

# , , AlLcJmti"e de,; nalion has been Jev;o"sl "",i ed f,om I""" JemO",I,o hi h"l ,,,,",val re,nLD 

# ,

TABLE C.J-6

- Expected Heat Input and Equivalent Coal Cost to Evaporate Aqueous Urea for MRY Unit 1 NOx Conlrols

() g!lll p y gn g l" gc (2)

_ HeaL ""1""00 to e"apo"'," urca**re"~"nl d,I"';~n**  "",[or ."umes 900 B,wlb "'qllirai "'-,00 on

## °10% ",ea eoncCTl'r.',"o (4 pans wo"r Lo I part OJea sol"'ion fil

### >0% eo"een"

.. ;o") ;"j",,,,d for loe e"iLnaLed**"m~""1 ~f**  ",ea usage. Coal heat roo"lenl 0[6,662**BLU~b.** un;1 cu,l ufW.71ImmBlU.**Esfim~led** Annual Aver:age UnitEquivalenl**CD~I** Consumnlion CoS! for Ao":.eous Urea EvapoT;llinn



## . Heal Required In '&[oi"alent Coal Evapnrale Consnmptinn fnr Coal Consumplion All• Aqne01[S Urea"), Heallnpn(lll, Co,l'll, Label'"**NO~** Conlrol Te<lmique mmlilul r Ton." r 1000$/ 

# , 

# , SNCR wi ASOFA 54,315 4,077 

# " 

# , AltemaLjv, des; tioo h

.. boeo rev;ou,l 

# ." 00 [romleaS! "mo".llo hi I,,,,, remowl rccnla 

# .**~.** i I; 1'= 

## ,

Minnkol. l'owerCoope"'live, Inc. Cl_ll Bums & MeDuunellAPPENDIXCl O&M eml ESlirIldlc" Appendix C References:



### ;EI'A OHioe ofAir Quality Planning nnd SLarldnnh (OAQI'S) p"blic"\ion EPN45Vfl-02-00I, Scclion 4.2, NOx ConlrOls NOx l'o'I_Comllmtion, Cllnpl'T 

### 1 _Sclcclivc Non·C.I"lylic Rccl""liol1, daled**(ktoh~T** 2000, po.<ted at lhcn wcb"ile: bJJp:!LW1if\v.eRa.gnv/un/calo/di, I/c.,4_2 ell 

### I.I'dl; Ch"pler 

### 2 - Selectivc Calalylic Reduction, dnlccl Oclober 200U, posled at lheir websile: h\to;IIwW'!'..epa.gnvIllnknI cl<1ir Iks4

-2 cjl2

## oP't£:

" "SlulionalY Souroe NOx nnd 

### PM Emi,sions 1I1 the 

### VIRAI' RCll""': 

### An Inili"1 A"cssmcnl ofEmissions, Con" 

### 01" and Air Qlwlily ImpacL,", OCI"bcr 

### 1, 20U3 We,lern Regional Ai' J'JJtner.;hip Final RqlOrt of Ihc WRAP MarketTcading FOrtlrn,**~eetion** VI: Summary ofEmi,"ion Conlrol, AvaiJ"ble for' Larg,-,**~lalionary** Sourec, "fNOx Jnd PM (by Rc"otion Enginee' mg Internalional), available al h IIp:1

### 1""\'",

..\\,rapair**,~fg/lo** I'llmsfmIPno:-;oPJl1.h1m1
,,; Bun]> & McDonndl inlernal dalaba.'e_

'" "Analysis ofCombuSIioLl Conlrol> [orReducing NO

### xEmi"ions Fcom Co;ll"fi"

..l EGU's 

### in the WRAl' Region" WRAP**nr~rr.** Report EGR ContractNumbcT :10204-IOI, prepared by Easlern Re>enrch Group, [nc., daled April 26, 2005, po"led allhcir websile;**hlt\l:!lwwv,'.wrapilir.on.:!forumsfsSlf/dooulnenl<;.!eicll>JNOxEljU/050426Cg~!::** fir'W%20EGU, in W,RAP Regjon-draft,pJf

, "C"mbustion MndJlicalion

_ An Economic**Al!em~li,'c** for Boiler NOx Control" UElt_11 92 (04/01), Folsom, Blair A, Tyson,**Thmnn~** 

### J. GE Po",er Systems, Schcpeclfld y, 1\ry, (001) POSll-.J at their' wcb,ile:**hllp:l/w.\VW,H~l)",\eL~"m,'pruJ** ,,,-,y/pmduol.,ilcol L**J"cdCllldo\\'nlo"d~K~l~** IQ2.rdf
,; "A(,,,cssmcTlt ofControl Tec1mology Oplion, [or BART.Eligible Sourceo, Steam Eleelric Boiler" llUlustnal Boiler", Cemenl Planls and Paper and P"lp hcililie'''' daled March 2005, po'ted**~l** lhelr we!>,ilC:**hllp:i/bron:<~.n.c.,caom.o[** wcurnmillcl·'lh1lzeIlJART ,-"nlml A"C""'CIlI pdr
,,; Budgetary**PmJ'0s~l,** F"cl Tech, Inc. NOxOUT" SNCIl and SNCJVFLUR'" Syslem" lor One 450 MW cyclone-fired <mil, claled Decemher?, 2004. ,;

Rum' & McDoonoll <:3_12 Minnkuill Power Coopcrdlive, Inc,