Wenatchee Works

Potline Scrubbing Scenario: Scaled Cost Estimate Sumamry

Scrubbing Scenario (# of Potlines) 1

Quote Used: Average

Interest Rate: 7.00%

Period of Annualization (Years) 15

Cost Effectiveness ($/ton) $ 33,100 $/ton SOx

Capital Equipment Costs

Total Purchased Equipment Costs (PEC) $60,046,604

Total Direct Installation Costs (DIC) $75,058,254

Total Direct Capital Costs (DCC) $135,104,858

Total Indirect Capital Costs (ICC) $15,011,651

Total Capital Investment Costs (TCIC) [DCC+ICC] $150,116,509

O&M Costs

Total Direct Annual Costs $7,283,440

Total Indirect Annual Costs $7,414,455

Total Annual Operating and Maintenance Costs $14,697,895

Single Scrubber, 1 Controlled Potline(s) - Cost Effectiveness Summary

SOx Reduction 941 tpy

Direct capital costs (DCC) $ 135,104,858

Indirect capital costs (ICC) $ 15,011,651

Total capital costs $ 150,116,509

Interest rate 7%

Period of annualization 15 years

Capital recovery discount factor 0.1098

Annualized capital cost $ 16,482,000

Total Annual Operating and Maintenance Costs $ 14,698,000

Total annual cost estimate $ 31,180,000

Cost of Wet Scrubber Control Option per ton SO x reduced: $ 33,100

This cost summary is based on 1 Potline(s) being controlled, using the Average vendor quote 

at an Interest Rate of 7% for 15 years.

Alternate Scenario Summary 3/27/2013
1 Enter the # of Lines

Average Pick from Drop Down List

7.00% Enter the % interest

15 years Enter the # of years

Scaling Equation 

Exponent n

Potlines Vendor

Quote #1

Average

(p1)

Reagent feed system 10% 0.33 $6,500,000 $7,350,000 Limestone Comsumption

SO2 removal system 35% 0.50 $22,750,000 $25,725,000 Flow Rate

Flue gas system 30% 0.50 $19,500,000 $22,050,000 Flow Rate

By-product handling system 10% 0.40 $6,500,000 $7,350,000 Gypsum

General support equipment 15% 0.15 $9,750,000 $11,025,000 Gypsum

TOTAL $65,000,000 $73,500,000

Value Calculations are based on the Hatch Scaling Equation: p2 = p1 x (Q2/Q1)

n

Reagent feed system $5,694,677

SO2 removal system $15,998,223

Flue gas system $13,712,763

By-product handling system $5,455,896

Cost Scaling Variable Q1 Q2 General support equipment $9,859,290

Parameter Tennesse 

Potlines

Wenatchee 

Potline

(Line #5 GTC)

Wenatchee 1 

Line Scenario $50,720,849

Clean flue gas flow rate (acfm) 1,582,432 612,009 612,009

Limestone consumption (tpy) 10,407 4,803 4,803

Gypsum production (tpy) 19,272 9,149 9,149

Note1: Scenario calculations have been estimated on the each line being equal.

$50,720,849

Scenario Cost Effectiveness : $33,100 $/ton SOx

LSFO Two Scrubber Average Cost Calculation : 

$28,700,000

$8,200,000

$12,300,000

$82,000,000

TOTAL

$9,859,290

$50,720,849

Two Scrubber Average Bid Estimate

Quote Used:

Interest Rate:

Period of Annualization:

Scaling of Capital Equipment Costs Based on Vendor Proposals

Wenatchee Works

Malaga, Washington

LSFO Scrubbing Potline Scrubbing Scenario

Fraction of 

Total 

Equipment 

Cost

Scrubber Component

Tennessee Potline Scrubber

Equipment Costs

Note2: Intalco 3-line Gypsum production rate is from page 3 of 

Final HATCH Pre-feisibility report (November 7, 2007) = 27,130 tpy

$24,600,000

Vendor

Quote #2

$8,200,000

Basis for 

HATCH Scaling

Value

Scenario Cost Calculations (Average Bid $$) - (JDJ)

Potline

$5,694,677

$15,998,223

$13,712,763

$5,455,896

Wenatchee Scrubber Equipment 

Cost Estimates (Average Bid 

Scaled )

Capital Equipment Costs

Wenatchee Single Scrubber Cost Calculations

3/27/2013
Potlines

Wenatchee Works

Malaga, Washington

Value Notes/References

Capital Investment Costs

Direct Capital Costs (DCC)

Purchased Equipment Costs (PEC)

Adsorber vessels with internals

$50,720,849

The two vendor average of $73,500,000 was based on the average vendor 

quotations for Tennessee Alcoa smelter, adjusted for Intalco's scrubber 

exhaust gas flow rate, limestone consumption, and gypsum generation, per 

the pre-feasibility report (Hatch 2007); the Intalco estimates were then scaled 

using Wenatchee Line #5's air flow to yield an adsoprber cost estimate of 

$50720849. Pumps Included

Limestone prep Included

Dewatering systems Included

Fans Included

Inlet ductwork Included

Stacks Included

Continuous Emission Monitoring system $80,000 $80,000 was the estimate for two Intalco scrubbing systems.

Subtotal (EC) $50,800,849

Instrumentation $2,540,042 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (5% of EC; adjusted from 

10% since basic instrumentation is included in proposal)

Sales tax $4,165,670 State sales tax rate for Washington adjusted to 8.2% 

Freight $2,540,042 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (5% of EC)

Total Purchased Equipment Costs (PEC) $60,046,604

Direct Installation Costs (DIC)

Foundations and supports $7,205,592 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (12% of PEC)

Handling and erection $48,037,283 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (80% of PEC; adjusted from 

40% to account for retrofit of existing plant and onsite fabrication)

Electrical $600,466 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Piping $18,013,981 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (30% of PEC)

Insulation $600,466 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Painting $600,466 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Total Direct Installation Costs (DIC) $75,058,254

Total Direct Capital Costs $135,104,858 Sum of PEC and DIC

Indirect Capital Costs (ICC)

Engineering $3,002,330 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (5% of PEC; adjusted from 

10% since vendor proposal included an allowance for engineering)

Construction and field expenses $6,004,660 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (10% of PEC)

Contractor fees $3,002,330 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (5% of PEC; adjusted from 

10% based on assumption that vendor will oversee scrubber installation)

Start-up $600,466 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Performance test $600,466 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Contingencies $1,801,398 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (3% of PEC)

Total Indirect Capital Costs $15,011,651

Total Capital Investment Costs (TCIC) $150,116,509 Sum of DCC and ICC

References:

Hatch. 2007. SO 2 Scrubbing for the INTALCO Primary Aluminum Smelter: Pre-Feasibility Report . July 26.

USEPA. 2002. EPA Air Pollution Control Cost Manual , Sixth Edition. EPA/452/B-02-001. January.

Captial Investment Cost Analysis for SO2 Control Using a Wet Scrubber

Capital Cost Calcs (Potline)

Wenatchee Single Scrubber Cost Calculations

3/27/2013
Potlines

Wenatchee Works

Malaga, Washington

Value Units Notes/References

Annual Operation and Maintenance Costs

Direct Annual Costs (DAC)

Operating labor

Operator $324,120 Assumes $37 per hour with one full-time operator, 3 shifts per 

day

Supervisor $48,618 USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (15% of 

operator costs)

Water $32,617

Water usage 168,609 gal/day Scaled from Intalco Pre-feasability Report (Hatch 2007)

Cost of water $0.00053 $/gal Assumed the same $/gallon water costs as reported for Intalco.

Limestone $158,510

Limestone usage 4,803 tons/yr Scaled from Intalco Pre-feasability Report (Hatch 2007)

Cost of limestone $33 $/ton Assumes $28/ton for 8 mesh size limestone plus $5/ton for 

shipping by barge

Compressed air $6,307

Compressed air usage 50 scfm Presumed equal to two scrubbers in Intalco's Pre-feasability 

Report (Hatch 2007) Not Scaled!

Cost of compressed air $0.24 $/1000 scf

Average compressed air generation cost for industrial facilities 

(http://www1.eere.energy.gov/industry/bestpractices/pdfs/comp

ressed_air1.pdf) 

Gypsum disposal $1,326,605

Gypsum generation rate 9,149 ton/yr Scaled from Intalco Pre-feasability Report (Hatch 2007)

Cost of gypsum disposal $145 $/ton Assumes USEPA's "No Disposal Cost" & "Syn-gyp Reuse" 

presumption at Intalco. 

Maintenance

Labor $673,920

Assumes $45 per hour with 4 full-time maintenance personnel, 

one shift per day, 5 days per week and 1 maintenance personnel 

for all other shifts [Reasonable per Ed Potter, Manager USPP Maintenance 

(3-21-13)]

Material $1,303,000

Cost for low sulfur boiler system with 1.7 macfm inlet/1.5 

macfm outlet, which is smaller than the potline system with 2.2 

macfm inlet/2.0 macfm outlet (Sargent & Lundy LLC 2003)

Electricity $3,409,742

Electricity usage 7,400 kWh/hr Presumed equal to two scrubbers in Intalco's Pre-feasability 

Report (Hatch 2007) Not Scaled!

Electricity cost $0.0526 $/kWh Facility average power rate for 2007 (Intalco controller)

Total Direct Annual Costs $7,283,440

Indirect Annual Costs (IAC)

Overhead $1,409,795 USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (60% of total 

labor and maintenance material costs)

General and administrative costs $3,002,330 USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (2% of TCIC)

Property tax $1,501,165 USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (1% of TCIC)

Insurance $1,501,165 USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (1% of TCIC)

Total Indirect Annual Costs $7,414,455 Sum of PEC and DIC

Total Annual Operating and Maintenance Costs $14,697,895 Sum of DAC and IAC

References:

Hatch. 2007. SO 2 Scrubbing for the INTALCO Primary Aluminum Smelter: Pre-Feasibility Report . July 26.

Sargent & Lundy LLC. 2003. Wet Flue Gas Desulfurization Technology Evaluation . Prepared for National Lime Association. January.

USEPA. 2002. EPA Air Pollution Control Cost Manual , Sixth Edition. EPA/452/B-02-001. January.

Operation and Maintenance Cost Analysis for SO2 Control Using a Wet Scrubber

O&M Cost Calcs (Potlines) Alternative Single Scrubber Cost Calculations
Installation of LSFO Wet Scrubber on Potline Exhaust

Reference

Uncontrolled Potline SOx emission rate: 5,480 lb/day Total Potline SOx Emission rate for 1 operating potline(s)

Primary potline control system uncontrolled SOx emission rate 5,427 lb/day Modeled SO2 Emission Rate leaving the GTC

SOx control efficiency 95%

Controlled SOx emission rate 271 lb/day

Uncontrolled annual SOx emissions 990.4 tpy

Controlled annual SOx emissions 49.5 tpy

SOx reduction: 940.9 tpy

Direct capital costs (DCC) $135,104,858

Indirect capital costs (ICC) $ 15,011,651

Total capital costs $150,116,509

Interest rate 7% USEPA 2002, Section 1, Chapter 2.4.2

Period of annualization 15 years USEPA Cost Control Manual, Section 5, Table 1.4 & USEPA Region 8 Directives

Capital recovery discount factor 0.1098 USEPA 2002, Section 1, Chapter 2.4.4.4, Equation 2.8a

Annualized capital cost $ 16,482,000 USEPA 2002, Section 1, Chapter 2.4.4.4, Equation 2.8

Operating labor costs $ 324,120

Supervisory labor costs $ 48,618

Maintenance labor costs $ 673,920

Maintenance material costs $ 1,303,000

Electricity costs $ 3,409,742

Water costs $ 32,617

Limestone costs $ 158,510

Compressed air costs $ 6,307

Gypsum disposal costs $ 1,326,605

Overhead $ 1,409,795

Property tax $ 1,501,165

Insurance $ 1,501,165

General and administrative costs $ 3,002,330

Total annual cost estimate $ 31,180,000

Cost of Wet Scrubber Control Option per ton SO x reduced $ 33,100

Potline Scrubber Cost Summary Alternative Single Scrubber Cost Calculations
Wenatchee Works

Parameter Tennesse 

Potlines

Intalco 

Potlines

Clean flue gas flow rate (acfm) 1,582,432 1,814,880 [Calcularted Value: Flow Based Scaling using Intalco Values]

Limestone consumption (tpy) 10,407 12,921 [Callculated Value: Note Below]

Gypsum production (tpy) 19,272 24,607 [Callculated Value: Note Below]

Water Consumption (gal/day) 500,000 [Callculated Value: Note Below]

Number of Potlines 2 3

One Line Comparative flue gas flow rate (acfm) 791,216 604,960 [Calculated value: Total scrubber flow ÷ # of potlines controlled]

Limestone Consumption

14,244 tons INTALCO

1,814,880 acfm INTALCO 612,009 acfm Wenatchee

Line #5 Gypsum Production

14,244 tons INTALCO 27,130 tons INTALCO

4,803 tons Wenatchee X tons Wenatchee

Water Usage

500,000 Gallons INTALCO

1,814,880 acfm INTALCO 612,009 acfm Wenatchee

Scaled

=

X

= 168,609

Wenatchee 

Potline

612,009

4,803

9,149

gallons/day Wenatchee

168,609

= 4,803 tons / yr of limestone Wenatchee

= = 9,149 tons/ yr of gypsum Wenatchee

=

X

612,009

1

$$$ Scaling and Parameter Data
Wenatchee Works

Potline GTC Flow, Velocity, and Emission Calculations

Velocity Calculation Formula

Q = A * V (Q = m3

/sec, A = m2, V = m/s)

V = Q / A

Q

π x D2

4

 Velocity Calculation

Stack Diameter = 4.27 meter Conversion Calculation

Volumetric Flow = 1,039,810 m

3

/hour 35.3147 ft3/m3

288.84 m

3

/s 1039810 m3/hr x 35.3147' ft3/m3' = 36,720,550 ft3

/hr

π = 3.14 60 min/hour

A = 14.32 m

2

612,009 ft3

/minute

Q

π x D2

4

289

14.32

V = 20.17 m/sec [Modeled GTC velocity]

3.28 ft/m

V = 66.17 ft/sec

Potline GTC SO2 Emission Rate

GTC

28.49 grams/sec 0.28 grams/sec

60 sec/minute 60 sec/minute

60 min/hour 60 min/hour

102,564 grams/hour 1,008grams/hour

453.59 grams/pound 453.59 grams/pound

226.11 pounds/hr 2.22 pounds/hr

5427 pounds/day 53 pounds/day 5,480 pounds/day

8,760 hrs/yr 8,760 hrs/yr

1,980,767 lbs/year 19,467 lbs/year 2,000,234 lbs/year

2000 lbs/ton 2000 lbs/ton

990.4 tons SO2 / year 10 tons SO2 / year 1,000 tons SO2 / year

V = 

V = 

V = 

Roof Monitor Total

Flow and Emission Calcs 7/7 3/27/2013