February 28, 2011

U.S. Environmental Protection Agency Region VIII 1595 Wynkoop Street Denver, CO 80202-1129 Attention: Vanessa Hinkle, 8P-AR

Dear Ms. Hinkle:

This letter serves as a response to the Clean Air Ac t Section 114(a) request issued by the U.S. Environmental Protection Agency (EPA) Region 8 towards the fulfillment of the Reasonable Progress (RP) goals and strategies under EPA’s Regi onal Haze Rule, per Title 40 of the Code of Federal Regulations (40 CFR) 51.308(d)(1) and 40 CFR 51.308(d)(3) (herein referred to as “114 request letter”). 1 This response contains further analysis of control technologies for the Plum Creek Manufacturing (Plum Creek) Columbia Falls Operations’ Riley Stoker Boiler and medium density fiberboard (MDF) Fiber Dryers and the Plum Creek Evergreen Division’s Riley Stoker Boiler, per EPA’s November 5, 2010 request.

The 114 request letter issued by the EPA is include d as Attachment A to this response. In the letter, EPA requests a control technology analysis for the emission units listed above in order to develop strategies towards achieving RP goals for Mo ntana. In the letter, EPA specifies that the analysis must address the factors included in 40 CFR 51.308(d)(i)(A): the costs of compliance, time necessary for compliance, the energy a nd non-air quality environmental impacts of compliance, and the remaining useful life of th e affected sources. The 114 request letter states that further analysis is warranted for the emi ssion units listed above, based on the information submitted by Plum Creek in March 2009 in res ponse to a previously issued Section 114(a) request regarding a more expansive lis t of emission units at the facilities. 2

The Regional Haze Rule covers emissions of pa rticulate matter (PM), sulfur dioxide (SO 2 ), and nitrogen oxides (NO x ). However, detailed control eval uations for emissions of PM and SO 2 are not included in this response for the following reasons:

3⁄4 PM emissions are already well-controlled from all the emission units identified in the 114 request letter.

• The Riley Stoker Boilers at the Columbia Falls Operations and at the Evergreen Division are equipped with dry Electrostatic Precipitators (ESPs).

• The Columbia Falls Operations Line 1 MDF Fiber Dryers exhaust through a Wet ESP.

1 Letter dated November 5, 2010 from Mr. Stephen S. Tu ber, EPA Region 8, to Mr. Thomas Ray, Plum Creek Manufacturing, received November 29, 2010, included as Attachment A. 2 The first 114 request regarding RP was issu ed by EPA Region 8 on January 29, 2009.Plum Creek Manufacturing - Page 2 February 28, 2011

• The Columbia Falls Operations Line 2 MDF Fiber Dryers are equipped with a Venturi Scrubber.

3⁄4 SO 2 emissions are minimal from all emission un its identified in the 114 request letter.

• The SO 2 emissions from the boilers and dryers are expected to be minimal as the units combust wood residue with only trace amounts of sulfur.

• Any residual sulfur in the fuel will be oxidized during the combustion process and would be expected to be captured by the alkaline wood ash, with minimal amounts of SO x exhausting. 3

• Commercial-grade natural gas is used in the Columbia Falls Operations boiler during startup. The natural gas also contains only trace amounts of sulfur.

The control technology evaluation presented in this letter report follows the guidelines for a Best Achievable Retrofit Technology (BART) analysis , per 40 CFR 51, Appendix Y. The report is organized as follows:

3⁄4 Section 1: BART Determination Methodology

3⁄4 Section 2: NO x Control Technology Descriptions

3⁄4 Section 3: Control Technology Analysis for NO x from the Riley Stoker Boilers

3⁄4 Section 4: Control Technology Analysis for NO x from the Line 2 MDF Fiber Dryers

3⁄4 Section 5: Control Technology Analysis for NO x from the Line 1 MDF Fiber Dryers

3⁄4 Section 6: Conclusion

3⁄4 Attachment A: Copy of 114 request letter

3⁄4 Attachment B: Supplemental material for the control technology evaluations



## S ECTION 

## 1. BART D ETERMINATION 

## M ETHODOLOGY

In the July 6, 2005, final BART Regulations and Guidelines, the EPA established guidelines for performing a BART Determination. 4 Essentially, the goal of the BART analysis is to determine the BART for each unit identified as a BART-eligib le source. In this analysis, there are no BART-eligible sources. However, the BART dete rmination approach is followed to conduct a control technology evaluation for the fulfillm ent of reasonable progress goals under 40 CFR 51.308(d) (1) and (3). This analysis must take into account several factors:

3⁄4 The availability and feasibility of retrofit control options

3⁄4 Pollution control equipment currently utilized

3 NCASI Technical Bulletin No. 884, Compilation of Criteria Air Pollutant Emissions Data for Sources at Pulp and Paper Mills Including Boilers, August 2004. Section 9.5.1 states: “...a significant amount of the fuel sulfur can be captured within the boiler itself by the alkaline wood ash.” 4 40 CFR Part 51, Appe ndix Y, Section IV.APlum Creek Manufacturing - Page 3 February 28, 2011

3⁄4 Costs of compliance for each control option

3⁄4 Remaining useful life of the facility

3⁄4 Energy and environmental impacts of the control options

Note that a visibility impacts analysis was not requested by EPA Region 8, and, thus, it is not included in this report

To guide selection of appropriate case-by-case BART limits, EPA noted that the BART Determination evaluation must include the following specific steps (excluding the visibility impacts analysis):

1. Identify all available retrofit control options

2. Eliminate technically infeasible options

3. Evaluate control effectiveness of remaining control technologies

4. Evaluate impacts and document results

Each of these steps is describ ed in the following sections.



### S TEP 

### 1: I DENTIFY 

### A LL 

### A VAILABLE 

### R ETROFIT 

### C ONTROL 

### O PTIONS

The first step in the BART Determination is th e identification of all retrofit control options, which: 5

...are those air pollution control technologies with a practical potential for application to the emissions unit and the regulated pollutant under evaluation...Technologies required as [Best Available Control Technology] BACT or [Lowest Achievable Emission Rate] LAER are available for BART purposes and must be included as control alternatives...We do not expect the source own er to purchase or construct a process or control device that has not already been demonstrated in practice.

The guidelines also note that New Source Perform ance Standards (NSPS) le vel controls should be considered, as should pollution prevention op tions and usage (or improvement to existing units) of add-on controls.



### S TEP 

### 2: E LIMINATE 

### T ECHNICALLY 

### I NFEASIBLE 

### O PTIONS

After the identification of control options, the next step in the analysis is to eliminate technically infeasible options. A control option is considered technically infeasible if technical difficulties (based on physical, chemical, or engineering pr inciples) would not a llow the option to be utilized successfully. A control is eliminated from consideration if there are process-specific

5 40 CFR Part 51, Appendi x Y, Section IV.D.1Plum Creek Manufacturing - Page 4 February 28, 2011

conditions that prohibit the implemen tation of control or if the highest control efficiency for that option would result in an emission level that is higher than any applicable regulatory limits.

Specifically, an option is considered technically feasible if it “has been installed and operated successfully for the type of source under revi ew under similar conditions, or the technology could be applied to the source under review.” 6 According to EPA’s Guidelines for BART Determinations under the Regional Haze Rules , technologies which have not yet been applied to (or permitted for) full scale operations need not be considered as available. Therefore, control options that have not been successfully demonstrated for a particular emission unit are considered technically infeasible and remove d from further consideration in this step. 7

To demonstrate that an option is not technically feasible, the source must evaluate and document that either (1) the characteristics of the exhaus t stream and/or the capabilities of the technology that would not allow the option to be used, or (2) the option is not commercially available.



### S TEP 

### 3: E VALUATE 

### C ONTROL 

### E FFECTIVENESS OF 

### R EMAINING 

### C ONTROL 

### T ECHNOLOGIES

The third step in the BART Determination is the evaluation of control effectiveness of any control options considered technically feasibl e. The control effectiveness should include comparing options on the same basis (e.g., lb/MMB tu). Varying control effectiveness levels for the same control option can be considered (e .g., 50% control versus 75% control). The effectiveness evaluation should also consider wa ys to improve the control associated with any existing control options already employed, especi ally when existing control devices are not achieving as great of reduction as the same control device on a similar source. 8



### S TEP 

### 4: E VALUATE 

### I MPACTS AND 

### D OCUMENT 

### R ESULTS

The fourth step in the BART Determination is to analyze the costs of compliance using the control option, the energy impacts of the control option, the non-air quality environmental impacts of the control option, and the remaining useful life of the equipment.

The first factor evaluated is the cost of co mpliance. Evaluation of this factor includes development of cost calculations necessary to dete rmine the average cost effectiveness, which is defined as “the total annualized costs of contro l divided by the annual emissions reductions.” 9
The incremental cost effectiveness can also be ev aluated in situations where a number of control options are being evaluated in order to compare those options to one another. Costs of compliance can be determined using EPA’s OAQPS Control Cost Manual as guidance. 10 Note that the emissions reductions included in the cost of compliance calculations should “represent a

6 40 CFR Part 51, Appendi x Y, Section IV.D.2 7 40 CFR Part 51, Appendix Y 8 40 CFR Part 51, Appendi x Y, Section IV.D.3 9 40 CFR Part 51, Appendi x Y, Section IV.D.4.b 10 EPA, OAQPS Control Cost Manual, Sixth Edition , January 2002. EPA-452/B-02-001.Plum Creek Manufacturing - Page 5 February 28, 2011

realistic depiction of anticipa ted annual emissions for the source...based upon actual emissions from a baseline period.” 11 Therefore, emission units with limited operation during the baseline period can consider similar limited operation (a nd limited emissions) in the cost effectiveness calculations.

The second factor evaluated is the energy impact. Energy impacts will result in additional costs or income to a source. Typically, these impact s are determined as part of the cost impact calculations, considering only the direct energy consumption.

The third factor evaluated is the non-air quality environmental impact. Environmental impacts include generation of additional solid or liqui d waste and the disposal of such waste.

The fourth factor evaluated is the remaining useful life of the source. If the remaining useful life of the equipment is less than the time period recommended by EPA’s OAQPS Control Cost Manual , the shortened life should be utilized in the cost evaluations for the purposes of amortizing costs of the retrofit.



## S ECTION 

## 2. NO X 

## C ONTROL 

## T ECHNOLOGY 

## D ESCRIPTIONS

This section contains a detailed description of each NO x control technology discussed in later sections of the report. While the work ing mechanism of these technologies in NO x removal is highlighted, the unit-specific applications of these options are discussed in Sections 3 through 5. The control technologies are classified based on whether they are post-combustion controls or combustion modifications that are pollution-preventive by design.



### P OST 

### -C OMBUSTION 

### C ONTROLS

The post-combustion control technologies described in detail below include Selective Catalytic Reduction (SCR) and Selective Non-Cataly tic Reduction (SNCR), which both reduce NO x in the flue gas by converting the NO x to N 2 and H 2 O.



### Selective Catalytic Reduction (SCR)

The SCR technique involves injecting ammonia or urea into a flue gas with a temperature of about 480 to 800°F, then passing the gas through a catalyst bed where NO x is converted to N 2 and H 2 O. The function of the catalyst is to lower th e activation energy of the NO decomposition reaction, therefore, lowering the temperature necessary to carry out the reaction. Depending onthe location of the SCR system in the combustion flue gas path, SCR technologies can be Tailend (Cold-side) or High-dust (Hot-side). A High-dust SCR system is placed between the economizer and air heater, while the Tail-end S CR is located downstream of the particulate control and air heater.

11 40 CFR Part 51, Appendi x Y, Section IV.D.4.dPlum Creek Manufacturing - Page 6 February 28, 2011

Babcock Power’s patented Regenerative SCR (RSCR) systems are “Tail-end” SCR systems on the cold side, after the particulate control device. In the RSCR configuration, the reagent is first introduced upstream of the RSCR unit. The flue gas/reagent mixture (previously cleaned of particulate matter) then enters one end of the system, where the flue gas mixture travels up through the (hot) ceramic heat retention canister to be reheated. The flue gas mixture then flows through the catalyst section, where the ammonia reacts with the NO x to form nitrogen and water. After the catalyst, the flue gas flows through a “retention” chamber, where a burner reheats the flue gas slightly. From this chamber, the flue gas then flows through the (cold) second canister and is used to heat this canister’s ceramic heat retention block. Once this cycle is complete, the air flow is diverted, so that the second canister is the inlet for the “cold” flue gas, and the first canister is the outlet for the cleaned flue gas. 12 The RSCR approach minimizes the supplemental fuel required to reheat the cold exhaust gas.



### Selective Non-Catalytic Reduction (SNCR)

SNCR is an exhaust gas treatment process in whic h urea or ammonia is injected into the exhaust gas. High temperatures, normally between 1,600 and 2,100°F, promote the reaction between urea or ammonia and NO x to form N 2 and water. 13 The effectiveness of SNCR systems depends on the inlet NO x concentration, temperature, mixing, residence time, reagent-to-NO x ratio, and fuel sulfur content. The temperature of the sy stem must fall within the appropriate range to avoid excess ammonia slip or the oxidation of NH 3 to NO x . Proper mixing of the reagent and the flue gas is necessary to ensure reduction of NO x . The residence time must be of an appropriate duration to allow completion of the reaction. If the reagent-to-NO x ratio is too high, excess NH 3 will become present in the exhaust

.

Outside of the design temperature window, the emissions are adversely affected. If the temperatures are too high, then the reagent may be oxidized, causing additional NO x emissions. If the temperatures are too low, then the reaction between the reagent and NO x is slowed, and emissions of the reagent will be present.



### C OMBUSTION 

### M ODIFICATION CONTROLS

The combustion modification control technologies described below decrease NO x emissions by preventing the formation of NO x during the combustion process, rather than by reducing NO x concentrations in the exhaust.



### Flue Gas Recirculation (FGR)

Flue gas recirculation (FGR) involves recycling a portion of the flue gas back into the combustion zone where inert combustion products in the recycled gas stream adsorb some of the heat generated by the combustion process, thus lowering peak flame temperature. The reduction

12 Abrams, Richard F. (Babcock Power Environmental, Inc.) and Kevin Toupin (Riley Power, Inc.). Efficient and Low Emission Stoker Fired Bioma ss Boiler Technology in Today’s Marketplace. Worcester, MA: Babcock Power Environmental, Inc. March 2007. http://www.babcockpower.com/pdf/t-200.pdf 13 EPA, Air Pollution Control Technology Fact Sheet, EPA-452/F-03-031, Se lective Non-Catalytic Reduction (SNCR), dated July 15, 2003.Plum Creek Manufacturing - Page 7 February 28, 2011

of the peak flame temperature reduces the formation of thermal NO x (conversion of N 2 in the combustion air to NO x due to high temperatures and the presence of oxygen).



### Fuel Staging

Also known as “reburning” or “off-stoichiometri c combustion,” fuel staging is a technique where 10 to 20 percent of the total fuel input is diverted to a second combustion zone downstream of the primary zone. The fuel in the secondary zone serves as a reducing agent, and NO formed in the primary combustion zone is reduced to N 2 . This technique usually employs natural gas or distillate oil as the fu el in the secondary combustion zone.



### Low NOx Burners (LNB)

Traditional burner design introduces both the fuel an d air into one combustion zone. To obtain optimal flames, large amounts of excess air must be combined with the fuel. This relatively “uncontrolled” combustion creates high flame temperatures and therefore higher NO x emissions.

To control the generation of thermal NO x , LNB technology stages combustion in the high temperature zone of the flame. The first stag e is a fuel-rich, oxygen-lean atmosphere where little oxygen is available for NO x formation, which reduces peak flame temperatures by delaying the completion of the combustion process. Com bustion is then completed downstream in the second stage where excess air is av ailable but temperatures are lower than the hottest portion of the primary flame core. LNB technology is most suitable for oil and gas combustion.



### Low Excess Air (LEA)

LEA involves reducing the amount of excess com bustion air to near-stoichiometric levels, reducing flame temperature, and decreasing thermal NO x formation.



### Staged Combustion

Staged combustion technologies such as Overfire Air (OFA) reduce NO x emissions by creating a “fuel-rich” zone via air staging (i.e., diverting a portion of the total amount of air required through separate ports so that partial combustion is carried out initially in the first stage with a lower air to fuel ratio than that of normal combustion, while secondary air is supplied to complete the combustion reaction in a subsequent combustion stage). Fuel-rich conditions in the first stage reduce fuel NO x formation by limiting the amount of oxygen available to react with the fuel bound nitrogen. Conditions in th e secondary combustion zone result in lower peak temperatures and thus, lower NO x emissions.



## S ECTION 

## 3. C ONTROL 

## T ECHNOLOGY 

## A NALYSIS FOR 

## NO X FROM THE 

## R ILEY 

## S TOKER 

## B OILERS 

## (C OLUMBIA 

## F ALLS AND 

## E VERGREEN 

## )

The Riley Stoker Boilers at the Columbia Falls Operations and Evergreen Division facility are similar in design. Both spreader-stoker boile rs combust wood residue, primarily as bark from each facility’s log debarking process, and both ar e load-following boilers used to meet the steamPlum Creek Manufacturing - Page 8 February 28, 2011

demand of various process operations. Sander dust burners supplement the hog fuel firing downstream of the spreader-stoker grate in bot h boilers. The sanderdust burners are also capable of firing natural gas, with a design cap acity of approximately 10 percent of the total boiler capacity. Natural gas firing only occurs during startup and rare events of sanderdust shortage. For reasons of similarity in design and operation, the control technology evaluations for both units are addressed in this section.

The firing rate varies for the Riley Stoker Boilers at the Columbia Falls Operations and at the Evergreen Division facility in order to meet th e steam demand at the r espective facilities. The load of the Columbia Falls Operations Rile y Stoker Boiler fluctuates between 50,000 pph steam and 150,000 pph steam, and the Evergreen Division Riley Stoker Boiler’s load varies between 30,000 pph steam and 70, 000 pph steam. These wide load changes often occur rapidly, sometimes swinging from the minimum load to the maximum load within thirty minutes.

The Riley Stoker Boiler at Columbia Falls Operati ons was installed in 1973. It supplies steam to the dry kilns, plywood press, log vats, and MDF platen press. The boiler is rated at 292 MMBtu/hr and 170,000 pounds per hour (pph) steam.

The Riley Stoker Boiler at the Evergreen Division facility was installed in 1971. The boiler is rated at 196 MMBtu/hr and 140,000 pph steam. It supplies steam for process operations such as the dry kilns, the veneer dryers, plywood presses, and the medium density overlay (MDO) press.



### B ACKGROUND ON 

### P OLLUTANT 

### F ORMATION

In industrial boiler and furnace combustion processes, NO x is formed by two fundamentally different mechanisms: fuel NO x and thermal NO x . Technical literature suggests that NO x formation from wood combustion is primarily fuel NO x . 14

“Fuel NO x ” forms when the fuel bound nitrogen compounds are converted into nitrogen oxides. The amount of fuel bound nitrogen converted to fuel NO x depends largely upon the fuel type, nitrogen content of the fuel, air supply, and boiler design (including combustion temperature). The reaction between elemental nitrogen and ox ygen to form nitrogen oxides happens very rapidly. Therefore, the primary mechanisms for reducing fuel NO x involve creating a minimum amount of excess oxygen available to react w ith the fuel bound nitrogen throughout the combustion process. 15

NO x formed in the high-temperature, post-flame re gion of the combustion equipment is “thermal NO x .” Temperature is the most important fact or, and at flame temperatures above 2,200°F, thermal NO x formation increases exponentially. 16

14 Webster, T.S. and S. Drennan. Low NO X Combustion of Biomass Fuels. Coen Company, Inc. http://www.coen.com/i_ht ml/white_lownoxbiom.html

. 15 Kraft, D.L. Bubbling Fluid Bed Boiler Emissions Firing Bark & Sludge. Barberton, OH: Babcock & Wilcox. Sept ember 1998. http://www.babcock.co m/library/pdf/BR-1661.pdf

. 16 Kraft, D.L. Bubbling Fluid Bed Boiler Emissions Firing Bark & Sludge. Barberton, OH: Babcock & Wilcox. Sept ember 1998. http://www.babcock.co m/library/pdf/BR-1661.pdf

.Plum Creek Manufacturing - Page 9 February 28, 2011

NO formation is inherent in all high temperature combustion processes. Nitrogen dioxide (NO 2 ) can then be formed in a reaction between th e NO and oxygen in the combustion gases. In stationary source combustion, little of the NO is converted to NO 2 before being emitted. However, the NO continues to oxidize in th e atmosphere. For this reason, all NO x emissions from boilers are usually reported as NO 2 .



### S TEP 

### 1: I DENTIFY 

### A LL 

### A VAILABLE 

### R ETROFIT 

### C ONTROL 

### O PTIONS

Potentially applicable NO x control technologies are identified based on a review of relevant information published in literature, determinations for similar un its identified from the a search of the EPA RACT/BACT/LAER Clearinghouse (RBLC) and from a review of recently issued permits for similar biomass boilers (a summary of relevant RBLC and permit search results is presented in Attachment B), and experience in conducting control technology reviews for similar types of equipment. After accounting for the physical and operational characteristics of the Riley Stoker Boilers, the post-combustion and combustion modification control technologies and strategies considered in this analysis for controlling NO x emissions include the following:

Post-Combustion Controls 3⁄4 Selective Catalytic Reduction (SCR) 3⁄4 Selective Non-Catalytic Reduction (SNCR)

Combustion Modification Controls 3⁄4 Flue Gas Recirculation (FGR) 3⁄4 Fuel Staging 3⁄4 Low NO x Burners (LNB) 3⁄4 Low Excess Air (LEA) 3⁄4 Staged Combustion 3⁄4 Good Operating Practices (base case)

Each of the technologies listed above are described in Section 2 of this letter report, with the exception of good operating practices for the Riley Stoker Boilers.

The formation of NO x can be controlled using good combus tion and boiler operation practices. Plum Creek adheres to a robust maintenance progr am to maintain the boilers’ burners, hog fuel feed system, fans, and other equipment in optimal condition. The boilers are also equipped with a computer control system used to maintain optimum air to fuel ratios and fuel feed rates. These good operating practices allow the facilities to meet the NO x permit limits for the Riley Stoker Boilers at the Columbia Falls Operations (134.50 lb/hr) and Evergreen Division facility (104 lb/hr).

Additionally, the Riley Stoker Boile rs inherently use a process simila r to fuel staging by design. The sanderdust burners, which typically supply approximately 10 percent of the heat to the boiler, are located downstream of the primary wood-fired flame.Plum Creek Manufacturing - Page 10 February 28, 2011



### S TEP 

### 2: E LIMINATE 

### T ECHNICALLY 

### I NFEASIBLE 

### O PTIONS

The technical feasibility of each iden tified technology for control of NO x emissions from the Riley Stoker Boilers is discu ssed in the following sections.



### Selective Catalytic Reduction (SCR)

Implementing SCR on industrial hog fuel boilers poses several technical challenges. Size constraints often make retrofitting an SCR system near the boiler impossible. Further, most hog fuel boilers’ temperature profiles are not appropriate for SCR, and the SCR system pressure drop requirements result in sizing concerns related to existing boiler fans. The National Council for Air and Stream Improvement (NCASI) notes that the high PM concentrations upstream of the PM control equipment (Hot-side/High-dust) w ould impede catalyst effectiveness and could result in deactivation or poisoning of the catal yst (requiring downtime to clean and/or replacethe catalyst), while the installation of SCR downstream of the PM control equipment (Coldside/Tail-end SCR) would render the gas stream too cold for effective reaction with the catalyst to reduce NO x . 17 In biomass boilers, plugging and fouling of the catalyst can occur due to large amounts of fly ash generated by the biomass.

The desired temperature range for SCR application is 480 to 800 ° F, while the maximum exhaust temperature of the Riley Stoker Boiler at Columbia Falls Operations is 500 ° F and the exhaust temperature for the boiler at the Evergreen Division facility is 430 ° F. While the exhaust temperatures of the two boilers are close to the range of operation of the SCR system, higher temperatures would likely be needed for op timum control efficiency for Tail-end SCR application. In an RCSR system, the regene rative heating reduces the required heat input; however, this reheating of the flue gas still repr esents a significant amount of auxiliary fuel that would be necessary for successful operation. More over, it is not considered available as RSCR has not been previously demonstrated on load-following industrial boilers. 18 As noted above, locating the SCR in a higher temperature region (Hot-side/High-Dust SCR) to avoid the issue use of auxiliary fuel would result in exposure to high particulate emissions from hog fuel combustion that could significantly damage the catalyst.

The technical difficulties described above apply generally to biomass boilers, and recent applications indicate that these difficulties ma y be overcome by advanced technologies and auxiliary heating of the Tail-end flue gas. Howe ver, the wide swings experienced by the Plum Creek boilers result in unstable exhaust temperatur es and would make it particularly difficult to control the reagent injection rate needed to ensure appropriate NO x reductions while avoiding excessive ammonia slip. For these reasons, S CR technology has never been successfully demonstrated for a load-following spreader-stoke r boiler with load swings comparable to the

17 NCASI Special Report 03-04, NO x Control in Forest Products Indus try Boilers: A Review of Technologies, Costs, and Industry Experience , August 2003. 18 A review of the RBLC database i ndicates that RSCR technology has previously been used only on a base-loaded utility boiler.Plum Creek Manufacturing - Page 11 February 28, 2011

Riley Stoker Boilers at the Columbia Falls Operations and Evergreen Division Facility. 19 , 20 BART guidelines state that technologies which have not yet been applied to (or permitted for) full scale operations need not be considered ava ilable; thus, technologies that have not been successfully implemented on a comparable emi ssion unit are eliminated in the technical infeasibility section of this evaluation. Theref ore, this technology is considered technically infeasible and is not considered further.



### Selective Non-Catalytic Reduction (SNCR)

Implementing SNCR on industrial load-following hog fuel boilers also poses several technical challenges for many of the same reasons that SCR technology is considered technically infeasible. In an SNCR system, the injection of the reagent must be applied in a narrow temperature window in order for the reduction r eaction to successfully complete. In a loadfollowing boiler, the region of the boiler where this temperature occurs varies depending on the firing rate, making it nearly impossible to cont rol the SNCR reaction temperature. Another factor preventing proper implementation of SN CR technology in load-following biomass boilers is inadequate reagent dispersion in the injection region, which can lead to significant amounts of unreacted ammonia exhausted to the atmosphere (i .e., large ammonia slip). At least one pulp mill wood-fired boiler had to abandon their SNCR system due to problems caused by poor dispersion of the reagent within the boiler. 21

While there have been recent advancements in SNCR technology that may aide in overcoming these technical hurdles, such as setting up multip le injection grids and the addition of sophisticated Continuous Emissions Monitori ng Systems (CEMS)-based feedback loops, SNCR has yet to be successfully demonstrated for a hog fuel boiler with swing loads comparable to the Riley Stoker Boilers at the Columbia Falls Operations and Evergreen Division facility. 22 , 23 Therefore, this technology is considered techni cally infeasible and is not considered further.



### Flue Gas Recirculation (FGR)

In FGR, a portion of the flue gas is routed to the combustion zone (up to 20% of the flue gas). The flue gas acts as a heat sink, thus lowering th e flame temperature. It also reduces the oxygen concentration. Both of these effects result in lower thermal NO x . Thus, FGR does not

19 NCASI Corporate Correspondent Memorandum No. 06-014, Information on Retrofit Control Measures for Kraft Pulp Mill Sources and Boilers for NO x , SO 2 and PM Emissions , June 2006. 20 A review of the RBLC database and of recently issu ed biomass boiler permits, performed in 2011, indicates that SCR technology has not been previous ly demonstrated on sim ilar load-following boilers. 21 NCASI Corporate Correspondent Memorandum No. 06-014, Information on Retrofit Control Measures for Kraft Pulp Mill Sources and Boilers for NO x , SO 2 and PM Emissions , June 2006. 22 NCASI Corporate Correspondent Memorandum No. 06-014, Information on Retrofit Control Measures for Kraft Pulp Mill Sources and Boilers for NO x , SO 2 and PM Emissions , June 2006. 23 A review of the RBLC database and of recently issued biom ass boiler permits, performed in February 2011, indicates that SNCR technology has not been previously demonstrated on similar load-following boilers. SNCR installations were identifie d for several industrial biom ass boilers. However, each of the boilers with SNCR does not operate under load-following conditions comparab le to the Plum Creek Riley Stoker Boilers. Further detail for each SNCR application is provided in Attachment B.Plum Creek Manufacturing - Page 12 February 28, 2011

significantly reduce NO x emissions for a biomass spreader stoker boiler since the majority of NO x emissions arise from fuel nitrogen.

FGR also requires considerable equipment for carrying the recirculated flue gas. For recirculation rates greater than 15 percent, an add itional fan is needed. The recirculation fan is a specialty fan that must be able to withstand th e high temperature and high particulate loading in the flue gas stream. High particulate loading in th e flue gas stream is of particular concern since the boilers’ fuel is wood. The increased flue g as volume would also increase gas velocity in the superheaters and boiler bank, which can cause additional pluggage and lost capacity.

FGR is not anticipated to provide a significant reduction in the NO x emissions from the Riley Stoker Boilers. Applying FGR as a means of controlling NO x is considered ineffective for the Riley Stoker Boilers and is not considered further.



### Fuel Staging (Reburning)

Fuel staging involves sending the fuel into a secondary inlet combustion zone for breaking the combustion event into several stages. It is usually facilitated by diverting natural gas or distillate oil in a secondary combustion zone downs tream of the primary zone. The Riley Stoker Boilers are primarily fired by hog fuel and only use natural gas during start-ups; therefore, they are unable to utilize this technique. Further, fuel staging often employs FGR, which is considered infeasible for the hog fuel boiler s due to its inability to minimize fuel NO x , the primary component of NO x from wood-waste combustion. 24 For these reasons, this technology has not been successfully demonstrated on wood-fire d boilers and is not considered further.



### Low NO x 

### Burners (LNB)

LNB are designed to mix fuel and air at optimum ra tios in order to keep the temperature low and maintain fuel-rich zones within the burner. This results in the reduction of thermal NO x formation. An LNB retrofit is usually done for o il/gas or coal-fired units. It is not possible to retrofit a wood-fired spreader stoker boiler with LNB, because the hog fuel is not fed into the boiler using a traditional burner. Sanderdust is fired using burners in the Riley Stoker Boilers; however, sanderdust burners also work differently than traditional burners and only supply a maximum of 10 percent of the boiler heat input. 25 Therefore, applying LNB as a means of controlling NO x is considered technically infeasible for the Riley Stoker Boilers and is not considered further.

24 NCASI Special Report 03-04, NO x Control in Forest Products In dustry Boilers: A Review of Technologies, Costs, and Industry Experience , August 2003. 25 The burners installed on the Line 2 MDF dryers that are referred to as “Low NO x Burners” in the Columbia Falls Operations permit, reduce NO x by applying staged combustion tec hnology. The Line 2 MDF Dryers burners limit the combustion ai r (creating a fuel-rich zone), and air is added downstream to co mplete combustion. Refer to the staged combustion discussion for the Boilers for further discussion regarding why staged combustion is considered technically infeasible for the Riley Stoker Boilers.Plum Creek Manufacturing - Page 13 February 28, 2011



### Low Excess Air (LEA)

LEA is difficult to employ in spreader stoker boilers because high excess air levels are needed for proper fuel burning. 26 LEA can result in the production of smoke, increased carbon monoxide (CO) emissions, and other problems as sociated with the boiler operation, including increased corrosion and fouling. 27 Thus, LEA is considered technically infeasible and is not considered further.



### Staged Combustion

Implementing staged combustion technology would require installation of OFA injection ports, which poses several site-specific technical obstacl es for Plum Creek’s Riley Stoker Boilers. The ports would need to be installed at the exact location where the current sanderdust burners are located, and installing OFA in the boilers’ sma ll combustion chambers could result in flame impingement on boiler walls, leading to tube wa ll overheating and mechanical failure. Flame impingement can also result in premature flame quenching and increased soot and CO emissions. 28 Staged combustion generally lengthens th e flame configuration so the applicability is limited to installations large enough to avoid flame impingement on internal surfaces. 29 Other issues related to general OFA retrofit installations include penetration of the boiler walls, which may affect the structural integrity of the unit, and which would require re-routing of the steam tubes. The reducing atmosphere created in th e fuel-rich primary combustion zone may also result in accelerated corrosion of the furnace. Additionally, grate corrosion and overheating may occur in stokers as primary air flow is diverted to overfire air ports. 30

Retrofitting the Riley Stoker Boilers with OFA inj ection ports is not technically feasible due to the numerous technical issues described above. Th erefore, OFA technology is considered to be technically infeasible and is not cons idered further in the analysis.



### S TEP 

### 3: E VALUATE 

### C ONTROL 

### E FFECTIVENESS OF 

### R EMAINING 

### C ONTROL 

### T ECHNOLOGIES

Good operating practices are the only available NO x control technology for the Riley Stoker Boilers. Therefore, there are no other technically feasible control options for evaluation.

26 Washington State Department of Ecology Publication No. 03-02-009, Hog Fuel Boiler RACT Determination , April 2003, http://www.ecy.wa.gov/biblio/0302009.html. 27 NCASI Special Report 03-04, NO X Control in Forest Products I ndustry Boilers: A Review of Technologies, Costs, and Industry Experience , August 2003. 28 NCASI Special Report 03-04, NO x Control in Forest Products In dustry Boilers: A Review of Technologies, Costs, and Industry Experience , August 2003. 29 Sloss, Leslie L. Nitrogen ox ides technology fact book. 1992. 30 Controlling Nitrogen Dioxides under the Clean Air Ac t, A Menu of Options: Industrial and Commercial Boilers, http://www.p2pays.org/ref/02/01245/3017103.pdfPlum Creek Manufacturing - Page 14 February 28, 2011



### S TEP 

### 4: E VALUATE 

### I MPACTS

Good combustion and boiler operation practices constitute the most suitable control option for the Riley Stoker Boilers.

The remaining useful life of the boilers is used for evaluating the economic feasibility of control options. Because all control technology options are considered technically infeasible, an economic analysis is not necessary for the c ontrol technology evaluation conducted for these boilers. However, the remaining useful life of the equipment may need to be considered in establishing RP goals for the region. The remaining useful life of each Riley Stoker Boiler is 10

years. 31



## S ECTION 

## 4. C ONTROL 

## T ECHNOLOGY 

## A NALYSIS FOR 

## NO X FROM THE 

## L INE 

## 2 MDF F IBER 

## D RYERS 

## (C OLUMBIA 

## F ALLS 

## )

The Line 2 MDF Dryers at Columbia Falls Operations are direct-contact dryers. The flue gas from the combustion chamber, rated at 85 MMBtu/hr, feeds two dryer lines (the first stage dryer and the second stage dryer). The combustion stage for the Line 2 MDF Fiber Dryers employs a staged combustion design. 32 First, the burners fire sanderdus t at less than stoichiometric oxygen to fuel ratio. The primary combustion stage is "fuel rich," thereby limiting formation of fuel NO x . As the flame progresses in the firebox, additi onal air is added to complete the combustion process. Due to the lower temperature needed in the secondary combustion zone, formation of thermal NO x is also reduced.

31 Engineering estimate by Plum Creek, emailed to Trin ity Consultants by Mitchell Leu, January 11, 2011. 32 It should be noted that the Columb ia Falls Operations air permit specifi es that the Line 2 Dryers employ LNB/FGR; however, the technology employed in practice is staged combustion. The burners contribute to lower NO x formation by firing the sanderdust at s ub-stoichiometric conditions; however, the burners themselves do not support the secondary combustion stage needed to complete the combustion process. Th e unit does not empl oy any form of FGR.Plum Creek Manufacturing - Page 15 February 28, 2011



### S TEP 

### 1: I DENTIFY 

### A LL 

### A VAILABLE 

### R ETROFIT 

### C ONTROL 

### O PTIONS

Potentially applicable NO x control technologies are identified based on a review of determinations for similar units identified from the RBLC search (Attachment B presents a summary of the RBLC search results for the NO x control technologies for MDF dryers). After accounting for the physical and operational charact eristics of the Line 2 MDF Fiber Dryers, the control technologies and strategies consider ed in this analysis for controlling NO x emissions include the following:

3⁄4 Selective Catalytic Reduction (SCR) 3⁄4 Sele cti ve Non-Catalytic Reduction (SNCR) 3⁄4 Flue Gas Recirculation (FGR) 3⁄4 Fuel Staging 3⁄4 Low Excess Air (LEA) 3⁄4 Low NO x Burner (LNB)/ Staged Combustion (base case)

The Line 2 MDF Fiber Dryers are currently equi pped with staged combustion, and hence this control is treated as a baseline scenario against wh ich additional control options are considered. Please refer to Section 2 of this report for a d escription of the control technologies listed above.



### S TEP 

### 2: E LIMINATE 

### T ECHNICALLY 

### I NFEASIBLE 

### O PTIONS

The technical feasibility of each identif ied technology for the control of NO x from the Line 2 MDF Fiber Dryers is discussed in the following sections.



### Selective Catalytic Reduction (SCR)

SCR technology has not been previously demonstr ated on a wood product dryer. This control option does not appear in the RBLC search resu lts for similar units. SCR technology is not feasible for wood products dryers because of the direct contact of the combustion air with the wood product material. If the reagent were to be injected in the optimal temperature range directly after the burner, the ammonia in the flue gas would deposit on the wood fibers (due to the direct-fired nature of the burners where the combustion gases come in contact with the material being dried), causing product damage.

For these reasons, SCR has not been successfully demonstrated on wood products dryers. Hence, it is considered technically infeasi ble and is not considered further.



### Selective Non-Catalytic Reduction (SNCR)

As previously discussed, SNCR systems are instal led where the temperature in the combustion zone of the unit reaches the optimum range for operation of the SNCR of 1600 to 2100 °F. The combustion zone for the Line 2 Dryers reach es a maximum temperature of approximately 1500 °F, lower than the minimum temperature need ed for SNCR. Moreover, as for SCR, if the reagent were to be injected near the optimal temperature range within the combustion chamber, the reagent in the flue gas would deposit on th e wood fibers, causing product damage. Due toPlum Creek Manufacturing - Page 16 February 28, 2011

these reasons, SNCR has not been successfully demonstrated on wood products dryers. Therefore, SNCR is considered technically infeasible and is not considered further.



### Flue Gas Recirculation (FGR)

FGR reduces thermal NO x by routing a portion of the flue gas to the burner to reduce thermal NO x . Most of the NO x emissions from wood-fired units arise from the fuel nitrogen, and the Line 2 Dryers are already designed with LNB and staged combustion technology. Since the minimal thermal NO x emissions that may form would already be controlled using the staged combustion technology, the addition of FGR woul d be ineffective. For these reasons, FGR has not been implemented on wood products dryers and is considered technically infeasible. 33



### Fuel Staging

As previously discussed, fuel staging is a technique where 10 – 20 percent of the total fuel input is diverted to a second combustion zone downstr eam of the primary zone, and natural gas or distillate oil are used in the secondary co mbustion zone, resulting in lower thermal NO x formation. This control option is not suitable for the Line 2 Dryers, because they are fired by wood residue in a small combustion chamber with no available footprint for a secondary combustion zone. Further, th is technique reduces thermal NO x , not fuel NO x (the primary component of the dryers’ exhaust). Hence, fuel staging is considered technically infeasible and is not considered further.



### Low Excess Air (LEA)

In an MDF dryer, there is limited thermal d ecomposition (partial combustion) of wood furnish components during the drying process. 34 As such, LEA would not be effective when employed in such dryers as high excess air levels are needed for proper fuel burning. Moreover, as seen in the case of the Boilers, LEA in the dryers too can result in the production of smoke, increased CO emissions, and other problems associated with the dryer operation including increased corrosion and fouling. 35 Thus, LEA is considered technically infeasible and is not considered further.



### S TEP 

### 3: E VALUATE 

### C ONTROL 

### E FFECTIVENESS OF 

### R EMAINING 

### C ONTROL 

### T ECHNOLOGIES

Staged combustion technology, presently inst alled and operational, is an available NO x control for the Line 2 Dryers. There are no other remaining control options which are technically feasible.

33 NCASI Special Report 03-04, NO x Control in Forest Products In dustry Boilers: A Review of Technologies, Costs, and Industry Experience , August 2003. 34 Prevention of Significant Air Qu ality Deterioration Review of Ge orgia-Pacific Wood Products LLC - Monticello MDF, http://www.gaepd.org/ai r/airpermit/downloads/permits/15900012/tv16820/1590012pd.pdf 35 NCASI Special Report 03-04, NO x Control in Forest Products In dustry Boilers: A Review of Technologies, Costs, and Industry Experience , August 2003.Plum Creek Manufacturing - Page 17 February 28, 2011



### S TEP 

### 4: E VALUATE 

### I MPACTS

Staged combustion constitutes the most suitable control option for the Line 2 MDF Fiber Dryers. Plum Creek employs a robust maintenance progr am that keeps this technology effective at reducing NO x emissions. The burner itself is also stri ctly controlled using computer controls that monitor and control fuel feed and combusti on air, monitor combustion zone temperatures as well as monitor fire brick temperatures.

The remaining useful life of the dryers is used for evaluating the economic feasibility of control options. Because all add-on control technology optio ns are considered technically infeasible, an economic analysis is not necessary for the control technology evaluation conducted for this unit. However, the remaining useful life of the equipm ent may need to be considered in establishing Reasonable Progress goals for the region. The re maining useful life of the Line 2 MDF Fiber Dryers is 10 years. 36



## S ECTION 

## 5. C ONTROL 

## T ECHNOLOGY 

## A NALYSIS FOR 

## NO X FROM THE 

## L INE 

## 1 MDF F IBER 

## D RYERS 

## (C OLUMBIA 

## F ALLS 

## O PERATIONS 

## )

The Line 1 MDF Fiber Dryers at the Columbia Fa lls Operations include a core dryer and a face dryer, each installed with a sande rdust burner with a capacity of 50 MMBtu/hr. The dryers can process up to 57 tons/hr of bone dry fiber. The size of the combustion chambers in the Line 1 Dryers is approximately one-fourth that of the combustion chamber for the Line 2 Dryers. This size difference is a direct result of the Line 2 Dryers including a staged combustion design requirement from the permitting process of the second line. The staged combustion technology implemented when the Line 2 Dryers were constructed requires four times the space to complete the combustion process.



### S TEP 

### 1: I DENTIFY 

### A LL 

### A VAILABLE 

### R ETROFIT 

### C ONTROL 

### O PTIONS

Potentially applicable NO x control technologies are identified based on a review of determinations for similar units identified from the RBLC search (a summary of relevant RBLC search results are presented in Attachment B). After accounting for the physical and operational characteristics of the Line 1 MDF Fiber Dryers, the control technologies and strategies considered in this analysis for controlling NO x emissions include the following:

3⁄4 Selective Catalytic Reduction (SCR) 3⁄4 Selective Non-Catalytic Reduction (SNCR) 3⁄4 Flue Gas Recirculation (FGR) 3⁄4 Fuel Staging 3⁄4 Low Excess Air (LEA) 3⁄4 Staged Combustion / Low NO x Burners (LNB) 3⁄4 Good Operating Practices (baseline)

36 Engineering estimate by Plum Creek, emailed to Trin ity Consultants by Mitchell Leu, January 11, 2011.Plum Creek Manufacturing - Page 18 February 28, 2011

Each of the technologies listed above are described in Section 2 of this letter report, with the exception of good operating practices for the Line 1 MDF Fiber Dryers.

The formation of NO x can be controlled using good operati on practices. Plum Creek adheres to a robust maintenance program for the Line 1 MD F Fiber Dryers. Maintaining the burners and other dryer equipment in good condition promotes proper combustion and supports good operating practices, including computer controlled optimization of air to fuel ratios and firing rates. The burners are also computer monitored for combustion zone temperatures.



### S TEP 

### 2: E LIMINATE 

### T ECHNICALLY 

### I NFEASIBLE 

### O PTIONS

SCR, SNCR, FGR, fuel staging, and LEA are c onsidered technically infeasible for the Line 1 Dryers for the same reasons outlined previously under Section 3, Step 2 for the Line 2 MDF Fiber Dryers. The technical feasibility for a pplying staged combustion for the control of NO x from the Line 1 MDF Fiber Dryers is discussed in the following section.



### Staged Combustion / Low NOx Burners (LNB)

The available technique for application of staged combustion / LNB technology for the combustion of sanderdust involves the same stag ed combustion process described for the Line 2 MDF Fiber Dryers. This technique involves firing th e sanderdust at sub-stoichiometric levels at the burners, and adding air through separate air por ts to complete the combustion process. The type of LNB technology that can be applied fo r natural gas or fuel oil combustion is not applicable for the combustion of sanderdust.

The application of staged combustion is limited by the longer and cooler flames produced as a consequence of improved air distribution contro l. The Line 1 MDF Fiber Dryers have a combustion chamber that is size-restricted. The firebox is one-fourth the size of that of the Line 2 MDF Fiber Dryers combustion chamber. The small size of the combustion chamber makes it impossible to retrofit the Line 1 MDF Fiber Dryers with a staged combustion technology without requiring replacement of the unit for the larger sized chamber. Where the current burners are located is footprint restrict ed for size so the larger combustion chambers would need to be relocated further away fro m the dryer also. This would add in sizable additional costs for ducting the combustion gases into the dryer. Therefore, staged combustion technology is considered technically infeasible fo r the retrofit of the Line 1 MDF Fiber Dryers.



### S TEP 

### 3: E VALUATE 

### C ONTROL 

### E FFECTIVENESS OF 

### R EMAINING 

### C ONTROL 

### T ECHNOLOGIES

Good operating practices are the only available NO x control technology for the Line 1 MDF Fiber Dryers. Therefore, there are no other tec hnically feasible control options for evaluation.Plum Creek Manufacturing - Page 19 February 28, 2011



### S TEP 

### 4: E VALUATE 

### I MPACTS

Good combustion practices constitute the most suita ble control option for the Line 1 MDF Fiber Dryers.

The remaining useful life of the unit is used for evaluating the economic feasibility of control options. Because all add-on control technology optio ns are considered technically infeasible, an economic analysis is not necessary for the c ontrol technology evaluation conducted for these dryers. However, the remaining useful life of the equipment may need to be considered in establishing Reasonable Progress goals for the region . The remaining useful life of the Line 1 MDF Fiber Dryers is 10 years. 37



## S ECTION 

## 6. C ONCLUSION

Plum Creek conducted a control technology evaluation to address requirements under the Regional Haze Rule for Reasonable Progress goals and strategies. Based on the evaluation presented in this letter, the existing contro l measures are the most suitable for PM, SO 2 , and NO x emissions from the Riley Stoker Boilers at the Co lumbia Falls Operations and at the Evergreen Division facility and the Line 1 and Line 2 MDF Fi ber Dryers at the Columbia Falls Operations.

PM emissions are well controlled for all four emission units, using a Venturi scrubber for the Line 2 MDF Fiber Dryers and ESP technology for the remaining units. Emissions of SO 2 are minimal, since all four units combust fuels with negligible amounts of sulfur (hog fuel, sanderdust, and natural gas). NO x emissions from the Riley Stoker Boilers are controlled using good operating practices, including employing a computerized control system to optimize the air and fuel feed rates. Additionally, the fi ring of hog fuel with supplemental downstream sanderdust burners results in low thermal NO x formation. NO x emissions from the Line 1 MDF Fiber Dryers are controlled using good operati ng practices, and the Line 2 MDF Fiber Dryers employ staged combustion technology to reduce NO x formation.

37 Engineering estimate by Plum Creek, emailed to Trin ity Consultants by Mitchell Leu, January 11, 2011.Plum Creek Manufacturing - Page 20 February 28, 2011

Should EPA Region 8 have any questions or requi re further information regarding the emission units or control technologies addressed in this le tter, Plum Creek looks forward to working with EPA Region 8 to provide add itional information to assist in establishing the Reasonable Progress goals and strategies for Montana.

Sincerely,

PLUM CREEK MANUFACTURING

Thomas Ray Vice President Montana Operations

Attachments

cc: Mr. Mitchell Leu, Plum Creek Ms. Anna Henolson, Trinity Consultants Ms. Anupama Krishnan, Trinity Consultants

## A TTACHMENT 

## A

EPA 114 Request Letter

## A TTACHMENT 

## B

RBLC and Biomass Boiler Permit Search ResultsTable B-1. RBLC Search Results for NOxcontrol devices on Hog Fuel Boilers1FACILITY STATEPERMITISSUANCE DATE EQUIPMENT PRIMARY FUEL THROUGHPUT UNIT CONTROL METHOD DESCRIPTIONEMISSIONLIMIT UNITCASE-BY-CASEBASIS NOTESMEADWESTVACO KENTUCKY, INC/WICKLIFFE KY 2/27/2002 BOILER, BARK BARK 631 MMBTU/H 0.4 LB/MMBTU BACT-PSDBOGALUSA MILL LA 11/23/2004NO. 12 HOGGED FUELBOILER BARK 787.5 MMBTU/HEXISTING OVERFIRE AIR SYSTEM WITH LOWNOX BURNERS IN THE UNDER GRATE AIRHEATER SYSTEM, PLUS GOOD COMBUSTIONPRACTICES 351.38 LB/H BACT-PSDS.D. WARREN CO. - SKOWHEGAN, ME ME 11/27/2001 BOILER, #2 WOOD WASTE 1300 MMBTU/H SCNR 260 LB/H BACT-PSDThe boiler is a 1300 MMBtu/hr unit which canfire multiple fuels including fuel oil, TDF,biomass, bark, LVHC gases, solid oily waste andkraft condensates. Additionally, the facility has apackage boiler and an additional hog fuel boilerthat can meet the facility's changing steamdemands. Based on the large size of the unit andthe load demands of the boiler, the boiler is notconsidered a comparable emissions source.DISTRICT ENERGY ST. PAUL, INC MN 11/15/2001 BOILER WOOD 550 MMBTU/HSELECTIVE, NON-CATALYTIC REDUCTION,SNCR 0.15LB/MMBTU,BIOMASS BACT-PSDThe boiler is used to produce steam for electricitygeneration and is likely to be base-loaded. Basedon boiler utility, the unit is not considered acomparable source.KODA ENERGY MN 8/23/2007 BIOMASS BOILER 3SNCR 0.25 LB/MMBTU BACT-PSDThe boiler is used to produce steam for electricitygeneration and is likely to be base-loaded. Basedon boiler utility, the unit is not considered acomparable source.KODA ENERGY MN 8/23/2007 BIOMASS BOILER 4SNCR 0.18 LB/MMBTU BACT-PSDThe boiler is used to produce steam for electricitygeneration and is likely to be base-loaded. Basedon boiler utility, the unit is not considered acomparable source.NORTHERN SUN ND 5/1/2006 WOOD/HULL FIRED BOILER BIOMASS COMBUSTION CONTROLS 0.2 LB/MM BTU BACT-PSDSCHILLER STATION NH 10/25/2004BOILER, WOOD FIRED CFB,UNIT #5 BIOMASS 720 MMBTU/h SELECTIVE NON-CATALYTIC REDUCTION 0.075 LB/MMBTU OtherThe boiler is used to produce steam for electricitygeneration and is likely to be base-loaded. Basedon boiler utility, the unit is not considered acomparable source.CONCORD STEAM CORPORATION NH 2/27/2009 BOILER #1 BIOMASS 32.62 T/HSELECTIVE CATALYTIC REDUCTION (SCR)SYSTEM 0.065 LB/MMBTU LAERThe boiler is used to produce steam for electricitygeneration and is likely to be base-loaded. Basedon boiler utility, the unit is not considered acomparable source.CLEAN POWER BERLIN LLC NH 9/25/2009 BOILER 1 WOOD CHIPS 40.75 T/H WOODSELECTIVE CATALYTIC REDUCTION (SCR)WITH STAGED COMBUSTION 0.065 LB/MMBTU LAERThe boiler is used to produce steam for electricitygeneration and is likely to be base-loaded. Basedon boiler utility, the unit is not considered acomparable source.BERLIN BIOPOWER NH 7/26/2010 EU01 BOILER #1 WOOD 1013 MMBTU/HSCR (COLD SIDE OF BAGHOUSE) WITHAMMONIA INJECTION 0.06 LB/MMBRU LAERThe boiler is used to produce steam for electricitygeneration and is likely to be base-loaded. Basedon boiler utility, the unit is not considered acomparable source.BERLIN BIOPOWER NH 7/26/2010 EU01 BOILER #1 WOOD 1013 MMBTU/HSCR (COLD SIDE OF BAGHOUSE) WITHAMMONIA INJECTION 0.06 LB/MMBTU BACT-PSDThe boiler is used to produce steam for electricitygeneration and is likely to be base-loaded. Basedon boiler utility, the unit is not considered acomparable source.SOUTH POINT BIOMASS GENERATION OH 4/4/2006 WOOD FIRED BOILERS (7) WOOD 318 MMBTU/H SELECTIVE CATALYTIC REDUCTION 27.98 LB/H BACT-PSDFacility proposes to generate electricity fromwood. As of December 2010, project is movingforward. It is not expected to be a load-followingboiler, hence is not a comparable source based onboiler utility.Plum Creek ManufacturingRBLC Search Boiler_v2.0.xlsx - 11.120Trinity ConsultantsFebruary 2011LINDALE RENEWABLE ENERGY TX 1/8/2010 Wood fired boiler biomass 73 T/H Selective Non-catalytic Reduction 0.15 LB/MMBTU BACT-PSDThe wood fired boiler used to produce steam foran electricity generation facility. It is not expectedto be a load-following boiler, hence is not acomparable source based on boiler utility.LUFKIN GENERATING PLANT TX 10/26/2009 Wood-fired Boiler wood 693 MMBtu/hr Selective Catalytic Reduction 0.075 LB/MMBTU BACT-PSDThe boiler is used to produce steam for electricitygeneration and is likely to be base-loaded. Basedon boiler utility, the unit is not considered acomparable source.INTERNATIONAL BIOFUELS, INC VA 12/13/2005WOOD THERMAL OXIDERSFOR WOOD PELLENTPROCESS WOOD/WOOD PASTE 43 MMBTU/H THERMAL OXIDIZERS AND CEM SYSTEM 18.9 LB/H BACT-PSDABERDEEN DIVISION WA 10/17/2002 HOG FUEL BOILER WASTE WOOD 310 MMBTU/H SNCR, BOILER DESIGN 0.15 LB/MMBTU BACT-PSDThe wood-fired boiler is used to generate steamfor electricity generation. Boilers used forelectricity generation are not expected to haveswing loads. Therefore, this boiler is not acomparable source based on boiler utility.SKAGIT COUNTY LUMBER MILL WA 1/25/2006WOOD-FIREDCOGENERATION UNIT BARK & WASTE WOOD 430 mmBtu/HSELECTIVE NONCATALYTIC REDUCTION(SNCR) 56 LB/H BACT-PSDThe boiler is used to produce steam for electricitygeneration and is likely to be base-loaded. Basedon boiler utility, the unit is not considered acomparable source.DARRINGTON ENERGY COGENERATION POWERPLANT WA 2/11/2005WOOD WASTE-FIREDBOILER WOOD WASTE 403 MMBtTU/H SNCR 0.12 LB/MMBTU BACT-PSDThe boiler is used to produce steam for electricitygeneration and is likely to be base-loaded. Basedon boiler utility, the unit is not considered acomparable source.CLEWISTON SUGAR MILL AND REFINERY FL 2004 BOILER 8 BAGASSE 1030 MMBTU/H SNCR 0.14 LB/MMBTU BACT-PSDThe unit is a new 1030 MMBtu/hr bagasse-firedboiler. The bagasse-fired boiler is not expected tooperate as a load-following boiler, because thesteam is co-generated into electricity onsite.Hence, it is not considered a comparable sourcebased on boiler utility.DEL-TIN FIBER L.L.C AR 2/28/2003 HEAT ENERGY SYSTEM BIOMASS 291 MMBTU/H SNCR 0.3 LB/MMBTU BACT-PSDThe unit is a heat-energy system and hence, is notcomparable emission source.INLAND PAPERBOARD TX 10/5/2004 BOILER BARK 856 MMBTU/H SNCR 0.166 LB/MMBTU BACT-PSDThe unit is an 856 MMBtu/hr bark boiler, and thefacility has two natural gas fired boilers. Due tothe large size of the unit and the two boilersexpected to meet the facility's changing steamdemand, the bark boiler is not expected to be acomparable emissions source.WEYERHAEUSER RED RIVER MILLLA 5/24/2006NO. 2 HOGGED FUEL BOILERWOOD 940 MMBTU/HSNCR0.15 LB/MMBTU BACT-PSDThe unit is a 940 MMBtu/hr boiler, and thefacility has a natural gas fired power boiler. Dueto the large size of the unit as well as the powerboiler expected to meet the changing steamdemand, the unit is not expected to have wideswing loads and is not considered a comparableemissions source.1. Search Criteria for RBLC: Date range from January 1, 2000 through January, 2011; Process Information included Boilers firedby all fuel types. Boilers with all other fuel types other than hog fuel are removed from the search results. Where fuel typeis not provided in RBLC entries, assumptions regarding possible fuel types are made based on industry. Thelist also includes a search of facilities with recently permitted industrial biomass boilers having SNCR systems installed.Plum Creek ManufacturingRBLC Search Boiler_v2.0.xlsx - 11.120Trinity ConsultantsFebruary 2011Table B-2. RBLC Search Results for NOxcontrol devices on Wood Products DryersFACILITY STATEPERMIT ISSUANCEDATEPROCESS NAME PRIMARY FUEL THROUGHPUT UNITCONTROL METHODDESCRIPTIONEMISSIONLIMITUNIT CASE-BY-CASE BASISPARAGON PANELS OF ALABAMA, L.L.C. AL 4/12/2006 WOOD FIBER PREP/DRYING 151 mmsf/yr LOW NOX BURNERS 80 LB/H BACT-PSDLOUISIANA PACIFIC CORPORATION AL 6/14/2006 BOARD PRESS BARK 85000 LB/H GOOD DESIGN/OPERATION 5.3 LB/H BACT-PSDLOUISIANA PACIFIC CORPORATION AL 6/14/2006 BARK BURNER/DRYER BARK 85000 lb/h 61.3 LB/H BACT-PSDGEORGIA-PACIFIC ORIENTED STRANDBOARD FACILITY AR 1/7/2003 ROTARY CHIP DRYER, (5) WOOD WASTES 600 MMSF/YR LOW NOX BURNER 14.66 LB/H BACT-PSDNORBORD GEORGIA GA 6/3/2005 WOOD FLAKE DRYERS WOOD 52 ODT/H 0.28 LB/MMBTU BACT-PSDOAKDALE OSB PLANT LA 6/13/2005 ROTARY DRYER NOS. 1-3 WOOD 300000MSF/YR 3/8inch basiLOW NOX BURNERS ANDWATER INJECTION69.77 LB/H BACT-PSDWEYERHAEUSER MI 6/11/2002 DRYERS AND BURNERS, WOOD CHIP WOOD 108000 LB/H LOW EXCESS-AIR FIRING 27.8 PPMDV BACT-PSDSAGOLA MILL MI 1/31/2008 FLAKE DRYERSLOW NOX BURNERS, GOODCOMBUSTION PRACTICES192.2 T/YR Other Case-by-CaseDIBOLL PARTICLEBOARD OPERATION TX 9/28/2001 PARTICLE BOARD PRESS, PB-53 NONE INDICATED 3.94 LB/H Other Case-by-CaseDIBOLL PARTICLEBOARD OPERATION TX 9/28/2001 (2) DRYERS NO 1 & 2, PB-47 NONE INDICATED 4.62 LB/H Other Case-by-CaseDIBOLL PARTICLEBOARD OPERATION TX 9/28/2001 DRYER NO 3, PB-49 NONE INDICATED 10.6 LB/H Other Case-by-CaseDIBOLL PARTICLEBOARD OPERATION TX 9/28/2001 DRYER NO 4, PB-50 NONE INDICATED 6.3 LB/H Other Case-by-CaseDIBOLL PARTICLEBOARD OPERATION TX 9/28/2001 SANDER DUST BOILER, PB-44 WOOD 40 MMBTU/H NONE INDICATED 57.2 LB/H Other Case-by-CaseJASPER ORIENTED STRANDBOARD MILL TX 2/9/2004 DRYERS 1-5 BYPASS4.12 LB/H BACT-PSDCARHAGE ORIENTED STRANDBOARD MILL TX 3/16/2004 DRYER BYPASS (2)4.2 LB/H BACT-PSDLOUISIANA-PACIFIC HAYWARD WI 6/17/2004 DRYER SYSTEM, LINE I, LINE II WOODGOOD COMBUSTIONPRACTICES, USE OF LOWNOX BURNERS IN OXIDATIONSYSTEM21.9 LB/H BACT-PSD1. Search Criteria for RBLC: Date range from January 1, 2000 through January, 2011; Process Information included Dryers firedby all fuel types. Dryers with all other fuel types other than hog fuel are removed from the search results. Wherefuel type is not provided in RBLC entries, assumptions regarding possible fuel types are made based on industry.Plum Creek ManufacturingRBLC Search MFD Dryer_v2.0.xlsx - 30.530Trinity ConsultantsFebruary 2011