Wenatchee Works

Potline Scrubbing Scenario: Scaled Cost Estimate Sumamry

Scrubbing Scenario (# of Potlines) 1

Quote Used: Low

Interest Rate: 7.00%

Period of Annualization (Years) 30

Cost Effectiveness ($/ton) $ 17,700 $/ton SOx

Capital Equipment Costs

Total Purchased Equipment Costs (PEC) $38,194,963

Total Direct Installation Costs (DIC) $47,743,703

Total Direct Capital Costs (DCC) $85,938,666

Total Indirect Capital Costs (ICC) $9,548,741

Total Capital Investment Costs (TCIC) [DCC+ICC] $95,487,407

O&M Costs

Total Direct Annual Costs $3,683,673

Total Indirect Annual Costs $5,229,291

Total Annual Operating and Maintenance Costs $8,912,964

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

SOx Reduction 941 tpy

Direct capital costs (DCC) $ 85,938,666

Indirect capital costs (ICC) $ 9,548,741

Total capital costs $ 95,487,407

Interest rate 7%

Period of annualization 30 years

Capital recovery discount factor 0.0806

Annualized capital cost $ 7,695,000

Total Annual Operating and Maintenance Costs $ 8,913,000

Total annual cost estimate $ 16,608,000

Cost of Wet Scrubber Control Option per ton SO x reduced: $ 17,700

This cost summary is based on 1 Potline(s) being controlled by a single Scrubber, using the 

Low vendor quote at an Interest Rate of 7% for 30 years.

3/27/2013
1 Enter the # of Lines

Low Pick from Drop Down List

7.00% Enter the % interest

30 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 $5,036,108

SO2 removal system $14,148,089

Flue gas system $12,126,933

By-product handling system $4,824,942

Cost Scaling Variable Q1 Q2 General support equipment $8,719,100

Parameter Tennesse 

Potlines

Wenatchee 

Potline

(Line #5 GTC)

Wenatchee 1 

Line Scenario $44,855,172

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.

$32,273,843 = $44855172 x (59/82)

Scenario Cost Effectiveness : $17,700 $/ton SOx

Single Scrubber Cost Adjustment Factor: (59/82)

$28,700,000

Scaled Scenario - LSFO Scrubber Cost Calculation : 

$8,200,000

$12,300,000

$82,000,000

TOTAL

$9,859,290

$50,720,849

Single Scrubber Low Bid Estimate

Quote Used:

Interest Rate:

Period of Annualization:

Scaling of Capital Equipment Costs Based on Vendor Proposals

Wenatchee Works

Malaga, Washington

Alternate Scrubbing Potline Scrubbing Scenario

Adjustment Factor Basis: Babcock Single vs. Two Scrubber Quote ($59 MM vs $82MM)

Wenatchee Scrubber Equipment 

Cost Estimates (Average Bid 

Scaled )

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

Basis for 

HATCH Scaling

Value

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

Potline

$5,694,677

$15,998,223

$13,712,763

$5,455,896

$24,600,000

Vendor

Quote #2

$8,200,000

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

$32,273,843

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 Prefeasability Report (Hatch 2007); the Intalco estimates were then scaled using 

Wenatchee Line #5's Air Flow to yield an adsorber cost estimate of 

$32,273,834.

Pumps Included

Limestone prep Included

Dewatering systems Included

Fans Included

Inlet ductwork Included

Stacks Included

Continuous Emission Monitoring system $40,000 $80,000 was originally for two Intalco systems, reduced to $40,000 to 

represent only one scrubber system.

Subtotal (EC) $32,313,843

Instrumentation $1,615,692 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 $2,649,735 State sales tax rate for Washington adjusted to 8.2% 

Freight $1,615,692 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (5% of EC)

Total Purchased Equipment Costs (PEC) $38,194,963

Direct Installation Costs (DIC)

Foundations and supports $4,583,396 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (12% of PEC)

Handling and erection $30,555,970 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 $381,950 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Piping $11,458,489 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (30% of PEC)

Insulation $381,950 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Painting $381,950 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Total Direct Installation Costs (DIC) $47,743,703

Total Direct Capital Costs $85,938,666 Sum of PEC and DIC

Indirect Capital Costs (ICC)

Engineering $1,909,748 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 $3,819,496 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (10% of PEC)

Contractor fees $1,909,748 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 $381,950 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Performance test $381,950 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (1% of PEC)

Contingencies $1,145,849 USEPA 2002, Section 5.2, Chapter 1, Table 1.3 (3% of PEC)

Total Indirect Capital Costs $9,548,741

Total Capital Investment Costs (TCIC) $95,487,407 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 Scaled from Intalco Pre-feasability Report (Hatch 2007)

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 $0

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

Cost of gypsum disposal $0 $/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 $1,136,581

Electricity usage 2,467 kWh/hr Scaled from Intalco Pre-feasability Report (Hatch 2007)

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

Total Direct Annual Costs $3,683,673

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 $1,909,748 USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (2% of TCIC)

Property tax $954,874 USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (1% of TCIC)

Insurance $954,874 USEPA 2002, Section 5.2, Chapter 1, Table 1.4 (1% of TCIC)

Total Indirect Annual Costs $5,229,291 Sum of PEC and DIC

Total Annual Operating and Maintenance Costs $8,912,964 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) $ 85,938,666

Indirect capital costs (ICC) $ 9,548,741

Total capital costs $ 95,487,407

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

Period of annualization 30 years Assumption

Capital recovery discount factor 0.0806 USEPA 2002, Section 1, Chapter 2.4.4.4, Equation 2.8a

Annualized capital cost $ 7,695,000 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 $ 1,136,581

Water costs $ 32,617

Limestone costs $ 158,510

Compressed air costs $ 6,307

Gypsum disposal costs $ -

Overhead $ 1,409,795

Property tax $ 954,874

Insurance $ 954,874

General and administrative costs $ 1,909,748

Total annual cost estimate $ 16,608,000

Cost of Wet Scrubber Control Option per ton SO x reduced $ 17,700

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