1 www.AndoverTechnology.com 

July 10, 2012

To: Doug Grano

Fm: Jim Staudt

Re: Colstrip 1 and 2 SNCR cost and performance

I have developed a revised cost estimate for the cost of SNCR at Colstrip 1 & 2 

utilizing cost information that I received from both Fuel Tech and Nalco Mobotec, the 

two SNCR vendors cited in PPL’s comments to EPA. Both companies provided me 

estimates of cost for a fully installed system (on a turnkey basis). Both companies also 

provided estimates of reagent usage so that cost effectiveness calculations could be made. 

The cost estimates shown here confirm the cost estimates originally developed by EPA. 

Summaries of the cost estimates are shown in Tables 1 and 2, and the spreadsheets are 

provided with this report including images of the emails received from Fuel Tech and 

Nalco Mobotec.

As shown, Fuel Tech’s information results in estimated cost effectiveness of the 

SNCR process of roughly $3,500/ton of NOx removed, only slightly higher than what 

was previously estimated by EPA. Fuel Tech estimated somewhat higher reagent 

consumption and the increased reagent consumption combined with a slightly higher 

reagent cost ($500/ton versus $400/ton) result in a higher overall reagent cost. This is 

offset to a large degree by the lower capital cost estimated by Fuel Tech. The higher 

reagent consumption is based upon Fuel Tech’s assessment of the furnace temperature 

and conditions at the site.

Nalco Mobotec’s estimate results in a cost effectiveness of roughly $2,800/ton 

and is generally lower in cost than Fuel Tech’s. But, the average of the two ($3,500/ton 

and $2,800/ton) results in an estimated cost effectiveness of $3,150/ton, only slightly 

lower than what was previously estimated by EPA.

As a result, the data from Fuel Tech and from Nalco Mobotec confirm EPA’s

estimate of cost effectiveness. They also confirm the estimated performance and are 

consistent with the performance predictions provided to PPL.
2 www.AndoverTechnology.com 

Both Fuel Tech and Mobotec’s estimate indicate that an ammonia slip limit of 10 

ppm may be necessary. Ammonia slip is normally a concern because of the impact on 

downstream equipment, especially the air preheater, from formation of ammonium 

bisulfate. Ammonia slip can also be a concern with respect to formation of detached 

plume from ammonium chloride or ammonium sulfate.

Although a 10 ppm slip limit is higher than typical for coal-fired boilers, this is 

acceptable in this situation because the Powder River Basin (PRB) coal at Colstrip is very 

high in alkalinity. The alkalinity reacts with and neutralizes the SO3, which means that 

there will be little or no SO3 present in the gases that enter the air preheater. For 

ammonium bisulfate deposition to be a problem ammonia and SO3 must be present in 

sufficient concentrations under the right conditions of temperature and moisture level. 

Because of the absence of SO3 upstream of the air preheater,

1 there should not be any 

problems from formation of ammonium bisulfate formation or ammonium sulfate. Also, 

PRB coal is generally low in chlorides and high in alkalinity and the high alkalinity in 

combination with the wet scrubber will assure that there are virtually no chlorides in the 

exhaust stack. As a result, even with 10 ppm of ammonia slip, there should not be a 

concern about impact to downstream equipment or with regard to formation of a plume 

from ammonia salts.

 1 In fact, the absence of SO3 in flue gas from PRB coal combustion is also why ESPs are so rarely used on 

boilers designed to burn PRB fuels and why SO3 conditioning systems are necessaryfor most 

boilers with ESPs that convert to PRB fuels from other fuels. SO3 helps provide ash the chargecarrying characteristics necessary for good capture in an ESP.
3 www.AndoverTechnology.com 

Table 1. Colstrip Unit 1or 2 BART Cost Analysis - SNCR+SOFA – from Fuel Tech Estimate

(2012 Dollars)

SNCR Capital Costs

Description Formula1 Value

Boiler Size (MMBtu/hr) QB 3982

NOx Removal Efficiency (%) ηNOx 25%

Cost Year 2012

Total Plant Costs ($) D= $17.5/kW times 333,000 kW $5,827,500

Allowance for Funds During Construction ($) E = 0 (Assumed for SCR) $0

Royalty Allowance ($) F = 0 (Assumed for SCR) $0

Preproduction Cost ($) G = 0.02 × (D + E) $116,550

Inventory Capital* ($) H = Vol reagent (gal) × Cost reagent ($/gal) $75,604

Initial Catalyst and Chemicals ($) I = 0 (Assumed for SNCR) $0

Total Capital Investment (TCI) ($) TCI = D + E + F + G + H + I $5,944,050

Total Capital Investment (TCI) ($) Per kW $18

SNCR Annual Costs

Direct Annnual Costs

 Maintenance Cost $89,161

 Reagent Cost $1,517,871

 Electricity Cost $20,710

 Water Cost $5,820

 Annual ΔCoal Cost $157,373

 Annual ΔAsh Cost -

Total Direct Annual Costs DAC $1,790,935

Indirect Annual Costs IDAC = TCI x CRF $561,118

Total Annual Costs TAC = DAC + IAC $2,352,054

SOFA Captial Costs

Total Captial Investment for SOFA ($)3 TCI $4,507,528

Total Capital Investment for SOFA ($/kW) Per kW $14

SOFA Annual Costs

Total Direct Annual Costs4 DAC $664,884

Indirect Annual Costs IDAC = TCI x CRF $425,511

Total Annual Costs TAC = DAC + IAC $1,090,395

Cost Effectivness

SOFA NOx Removed (tons/yr) 1,432

SOFA Cost Effectiveness ($/ton removed) $761

SNCR NOx Removed (tons/yr) 664

SNCR Cost Effectiveness ($/ton removed) $3,540

SNCR+SOFA NOx Removed (tons/yr) 2,097

SNCR+SOFA Cost Effectiveness ($/ton removed) $1,642
4 www.AndoverTechnology.com 

From: Alexander Dainoff [mailto:ADainoff@ftek.com] 

Sent: Wednesday, June 27, 2012 4:01 PM

To: Jim Staudt

Cc: Dale T. Pfaff; William Cummings; Terry Brown

Subject: Re: PPL colstrip SNCR

Jim,

As per our discussion, we have the following comments on the Colstrip Unit

1 BART Cost analysis you provided:

1. Based on our previous proposal on this unit as well as similar SNCR Turnkey installations by 

Fuel Tech, the total turnkey installed cost should be in the $15 to $20/kw range.

2. From the recently submitted proposal for this unit, 25% NOx reduction from a baseline of 

0.20lbs/MMBtu required an NSR of 1.75. This was based on a calculated FEGT of over 2500oF at the 

bullnose elevation. The Gas Temperature has a significant impact on the Process Design, system 

configuration and reagent consumption.

As an example, on a recent SNCR Process demonstration on a 750MW T-fired boiler burning PRB, 

The FEGT 2 feet above the bullnose elevation was 2334oF and were able to achieve 25% NOx reduction 

with combined HERT and NOxOUT wall injectors at an NSR of 1.1

Therefore based on actual measured gas temperature on these units, the reagent consumption 

could be reduced significantly.

I hope this information is helpful. If you need additional details,

please contact me.

Thanks,

Alexander S. Dainoff

Regional Sales Manager

Fuel Tech Inc.

120 Long Ridge Road

Stamford, CT 06902

Phone: 203-323-8401

FAX: 203-967-2366

Mobile: 201-970-4044

ADainoff@ftek.com

On 6/27/12 10:29 AM, "Jim Staudt" <staudt@andovertechnology.com> wrote:

>Alex,

>

>I've attached EPA's estimate of the cost of SNCR and SOFA at Colstrip unit 1 (the unit 2 analysis is 

identical). They show an assumed NSR of 1.38 (see page 5). This is public and in the docket. If you could 

comment on whether or not this is a reasonable (if not conservative) assumption for NSR with 25% 

reduction, that would be helpful.

>

>Thanks in advance for your help.

>
5 www.AndoverTechnology.com 

>

>Best Regards,

>

>Jim Staudt

>Andover Technology Partners

>office: 978-683-9599

>mobile: 978- 884-5510
6 www.AndoverTechnology.com 

Table 2. Colstrip Unit 1or 2 BART Cost Analysis - SNCR+SOFA – from Nalco Mobotec Estimate

(2012 Dollars)

SNCR Capital Costs

Description Formula1 Value

Boiler Size (MMBtu/hr) QB 3982

NOx Removal Efficiency (%) ηNOx 25%

Cost Year 2012

Total Plant Costs ($) D= Average($10.5,$16)/kW times 333,000 kW $4,412,250

Allowance for Funds During Construction ($) E = 0 (Assumed for SCR) $0

Royalty Allowance ($) F = 0 (Assumed for SCR) $0

Preproduction Cost ($) G = 0.02 × (D + E) $88,245

Inventory Capital* ($) H = Vol reagent (gal) × Cost reagent ($/gal) $59,619

Initial Catalyst and Chemicals ($) I = 0 (Assumed for SNCR) $0

Total Capital Investment (TCI) ($) TCI = D + E + F + G + H + I $4,500,495

Total Capital Investment (TCI) ($) Per kW $14

SNCR Annual Costs

Direct Annnual Costs

 Maintenance Cost $67,507

 Reagent Cost $1,196,950

 Electricity Cost $16,331

 Water Cost $4,590

 Annual ΔCoal Cost $124,100

 Annual ΔAsh Cost -

Total Direct Annual Costs DAC $1,409,478

Indirect Annual Costs IDAC = TCI x CRF $424,847

Total Annual Costs TAC = DAC + IAC $1,834,325

SOFA Captial Costs

Total Captial Investment for SOFA ($)3 TCI $4,507,528

Total Capital Investment for SOFA ($/kW) Per kW $14

SOFA Annual Costs

Total Direct Annual Costs4 DAC $664,884

Indirect Annual Costs IDAC = TCI x CRF $425,511

Total Annual Costs TAC = DAC + IAC $1,090,395

Cost Effectivness

SOFA NOx Removed (tons/yr) 1,432

SOFA Cost Effectiveness ($/ton removed) $761

SNCR NOx Removed (tons/yr) 664

SNCR Cost Effectiveness ($/ton removed) $2,761

SNCR+SOFA NOx Removed (tons/yr) 2,097

SNCR+SOFA Cost Effectiveness ($/ton removed) $1,395
7 www.AndoverTechnology.com 

From: Jeffrey M Filipski [mailto:jmfilipski@nalco.com] 

Sent: Wednesday, June 27, 2012 6:25 PM

To: Jim Staudt

Cc: Gary C Tonnemacher; Jeffrey M Filipski

Subject: SNCR

Jim,

The cost range that we would use for a range of boilers in the 100-400Mw range for SNCR installation is 

between $10.50 - $16.00 /KW installed cost. The estimate you had does seem high. The NSR seems a tad 

high @ 1.38 but I’m assuming that is due to the NOx reduction being set @ 25% which means you are 

going to have 10ppm slip.

Under this scenario, I believe that is a reasonable number to use. This is double the industry standard slip 

for coal fired units. Due to the low sulfur coal, there may be some leeway on not forming ABS @ the air 

heater with this high of slip. If you lower the slip to 5ppm, the NSR will obviously go down, and the NOx 

reduction will go to only 20%.

Mobotec typically has NSR’s lower than or equal to Fuel Tech, so the operating costs would tend to be 

slightly lower. For this situation, we would use a NSR of appx 1.0. with appx +/- 20% 

Jeff

From: Jim Staudt [mailto:staudt@andovertechnology.com]

Sent: Wednesday, June 27, 2012 9:29 AM

To: Jeffrey M Filipski

Subject: RE: Colstrip Units 1 and 2 SNCR

Jeff,

I’ve attached EPA’s estimate of the cost of SNCR and SOFA at Colstrip unit 1 (the unit 2 analysis is 

identical). They show an assumed NSR of 1.38 (see page 5). This is public and in the docket. If you could 

comment on whether or not this is a reasonable (if not conservative) assumption for NSR with 25% 

reduction, that would be helpful.

Thanks in advance for your help.

Best Regards,

Jim Staudt

Andover Technology Partners

office: 978-683-9599

mobile: 978- 884-5510