# LG&E Services Company LG&E Services Company

Contract No. 501654 Contract No. 501654 Mill Creek FGD Performance Upgrade Study Mill Creek FGD Performance Upgrade Study

February 2011 

### Assess the feasibility of upgrad ing the Mill Creek Units 1 & 2 ing the Mill Creek Units 1 & 2

FGD ’ s and upgrading the existing Mill Creek 4 FGD and and upgrading the existing Mill Creek 4 FGD and utilizing it for Mill Creek Unit 3 utilizing it for Mill Creek Unit 3

## L G & E S e r v i c e s C o m p a n y

C o n t r a c t N o

. 5 0 1 6 5 4

M i l l C r e e k F G D P e r f o r m a n c e U p g r a d e S t u d y

“Assess the feasibility of upgrading the Mill Creek Units 1&2 FGD’s and upgrading the existing Mill Creek 4 FGD and utilizing it for Mill Creek Unit 3”

### LG&E Services Company
Contract No. 501654
Mill Creek FGD Perfor mance Upgrade Study

Table of Contents February 15, 2011

1.0 Executive Summary

2.0 BPEI WFGD Technology Features and Benefits

2.1 Extensive 3-D Modeling Technology

2.2 Dual Flow Nozzles

2.3 Wall Baffles

2.4 Agitators

2.5 Mist Eliminators

2.6 Recycle Pumps

3.0 Base Case – Existing Absorb er Design and Operation

3.1 Executive Summary – Base Case

3.2 System Description

3.3 Current Process Operation

3.4 Spray Header Arrangement / Spray Nozzle Coverage

3.5 Recycle Pump Performance

3.6 Absorber Inlet Design

3.7 Predicted Absorber Performance

3.8 Predicted Absorber Performance

3.9 Construction

4.0 Case 2 – Required Equipment Modifications to Reliably Achieve 96% SO2 Removal

4.1 Executive Summary – Case 2, 96% SO2 Removal

4.2 Case 2 – Work Scope

4.3 Spray Header Arrangement / Spray Nozzle Coverage

4.4 Wall Baffles

4.5 Liquid-to-Gas Ration

4.6 Absorber Solids / Liquid Residence Time

4.7 Oxidation Air Blowers and Agitators

4.8 Construction

5.0 Case 3 – Maximum Achievable SO2 Removal Efficiency

5.1 Executive Summary

5.2 Case 3 – Scope of Work

5.3 Optimization of Absorber General Arrangement

5.4 Impact of Reagent Grind Size

5.5 Im pact of Organic Acid

5.6 Performance Testing and Modeling

5.7 Construction6.0 Construction Plan

7.0 Budget Price

8.0 Project Schedule

Attachments

– Basis of Design Description

– Process Flow Diagrams

– Absorber System General Arrangement Drawings

– Description of Equipment being Modified

– Work Breakdown Structure

– Overall Project Schedule

– Construction & Outage High Level Schedule

– Budget Engineering Procurement and Construction Estimate1 EXECUTIVE SUMMARY

Babcock Power Environmental Inc. (BPEI) has conduc ted an extensive evalua tion of the existing Wet Flue Gas Desulfurization (WFGD) Systems at Louisville Gas and El ectric’s (LG&E’s) Mill Creek Generating Station, Units 1, 2 and 4. The purpose of the ev aluation was to determine the feasibility of modifying the existing WF GD equipment to enhance the overall SO 2 emissions performance. BPEI was requested to prepare th ree primary options for LG&E’s consideration,

as follows:

o Base Case – Current SO 2 Removal Efficiency

o Case 2 – System Upgrade – Target: 96% SO 2 Removal Efficiency

o Case 3 – System Optimization Upgrade: 98% SO 2 Removal Efficiency

BPEI evaluated multiple alternatives to accomplis h LG&E’s objectives, from minimal change to extensive retrofit, and presents in this report the most favorable options for LG&E’s consideration. BPEI utilized proprietary pro cess software modeling as well as graphical depictions of each phase and any required pro cess infrastructure upgrades. Discussions with plant engineers and reviews of existing plant equipment provided the necessary information to develop a baseline performance model from wh ich to launch the analysis of each option.

The report also includes the following Project Deliverables:

 Basis of Design Description

 Process Flow Diagrams

 Absorber System General Arrangement Drawings

 Description of Equipment being Modified

 Work Breakdown Structure

 Overall Project Schedule

 Construction and Outage High Level Schedule

 Budget Engineering, Procurement and Construction Estimate

The evaluation was based on the flue gas from Un it 3 being routed to the existing Unit 4 WFGD

and a new WFGD installed to condition the flue gas from Unit 4. For the purposes of this report and in regard to scrubber modifications, “Unit 3” refers the Unit 3 boiler train ducted to the current Unit 4 WFGD system.

Unit Descriptions

Mill Creek Units 1 and 2 are 330 MW each, controlled circulation, pulverized coal fired boilers, manufactured by Combustion Engi neering. They have been in service since 1972 and 1975, respectively. During operation, flue gas exits th e air heaters and passes through the ESP, Booster Fans and WFGD and then exits through the stack. The original WFGD systems were provided by Combustion Engineering and have been modifi ed multiple times throughout their operational

Page 1 of 59history. Recently, spray headers were modified and perforated trays adde d between spray levels 1 and 2. Today, Units 1 and 2 operate w ith all spray levels in service.

Mill Creek Unit 3 is a 425 MW pulverized coal fired boiler, manufactured by Babcock & Wilcox Co. It has been in service since 1978. Flue gas exits the air heaters and passes through the ESP,

ID Fan and WFGD and then exits through the stack. This unit also includes an SCR System that was designed and supplied by Riley Power Inc. (RPI), a Babcock Power Inc. Company.

Today, Units 1 and 2 operate with all spray levels in service. The Units burn bituminous coal

with an SO 2 level of 5.4 lb./MMBtu. The reported SO 2 removal is 90-92%, with the reaction tank pH normally set to 5.7.

This evaluation will utilize a design coal that has an SO 2 level of 6.3 lb./MMBtu.

Base Case - Current SO 2 Removal Efficiency

Technical Description – The task objective of the Base Case is to determine the maximum

achievable SO 2 efficiency without performing modificati ons to the existing equipment, based on a specified design coal with an SO 2 level of 6.3 lb./MMBtu. The work associated with the Base Case has been completed by BPEI and is presented in this report.

Engineering Scope of Work – The mechanisms for achieving the required performance are optimization of the spray coverage and droplet distribution, while maintaining droplet size for peak liquid-to-gas interaction. This is performed by modifying so me of the existing equipment and adding new equipment.

BPEI modeled the existing absorber systems on M ill Creek Units 1, 2, and 3 (Unit 3 flue gas to be redirected to existing Unit 4 WFGD system) using proprietary softwa re and data obtained from plant personnel to create a realistic baseline performance m odel. BPEI analyzed performance of the model, alteri ng key variables such as flue gas flow, coal sulfur content, recycle pump flow and pressure, recycle spray no zzle type, nozzle spray a ngles, nozzle coverage,

etc. to determine what modifications to the ex isting systems would provide the most economical reliable performance enhancements for each system. The base model also provides critical feedback to the design engineers to confirm that theories and calculations used in the model are accurate and appropriate as a starting point for performance enhancement using BPEI’s proven techniques. The evaluation was based on the flue gas from Unit 3 being routed to the existing

Unit 4 WFGD and a new WFGD installed to condition the flue gas from Unit 4.

Performance – Based on BPEI’s evaluation of th e existing equipment and performance capabilities, it has been determined that Units 1 and 2 can be expected to achieve a maximum

88% SO 2 removal. Unit 3 can be expected to achieve a maximum 91% SO 2 removal. Both of these values are based on a design coal that has an SO 2 level of 6.3 lb./MMBt u. The results are based on the spray nozzles and recycle pumps opera ting as designed. Also, the results reflect a plant modification to route the fl ue gas from Unit 3 to the Unit 4 WFGD, which has an absorber with 25% additional capacity. The higher removal in Unit 3 is attributed to this modification.

Page 2 of 59Case 2 – System Upgrade – Target: 96% SO 2 Removal Efficiency

Technical Description – The task objective of Case 2 was to provide to LG&E the most economical, reliable method to obtain 96% SO 2 removal for each of the Mill Creek Units. BPEI modeled the existing absorber systems on Mill Cr eek Units 1, 2, and 3 (Unit 3 flue gas to be redirected to existing Unit 4 WFGD system) usi ng proprietary software and data obtained from plant personnel to create a realistic baseline performance model. The process parameters were then modified using BPEI’s hi storical experience as follows:

Units 1 and 2:

 Change Spray Level 1 nozzles from dow n-only to dual-flow, double-down nozzles.

 Change Spray Level 2 nozzles from down-only to dual-flow, up-down nozzles.

 Change Spray Level 3 nozzles from down-only to dual-flow, up-down nozzles.

 Change Spray Level 4 nozzles from dow n-only to dual-flow, double-down nozzles.

 Change spray nozzle angle on Units 1 and 2 from 80 o to 120 o

.

 Add wall baffles to Spray Levels 2 and 3.

Unit 3

 Change Spray Level 1 nozzles from dow n-only to dual-flow, double-down nozzles.

 Change Spray Level 2 nozzles from down-only to dual-flow, up-down nozzles.

 Change Spray Level 3 nozzles from down-only to dual-flow, up-down nozzles.

 Change Spray Level 4 nozzles from dow n-only to dual-flow, double-down nozzles.

 Add wall baffles to Spray Levels 2 and 3.

The model was then used to determine the required recycle pump flow to achieve 96% SO 2 removal.

Units 1 and 2

 Increase the recycle pump capacity from all at 600 hp to 3 pumps at 500 hp and 5 pumps at 700 hp resulting in a change to the Liquid-to -Gas (L/G) ratio, from 112 gal/kacf to 141 gal/kacf. The recycle pump capacity change in Units 1 and 2 will alter the Liquid-to-Gas (L/G) ratio. Generally L/G ratio trends with removal rate, therefor e increasing the flow through the recycle pumps and nozzl es corresponds to greater SO 2 removal.

Unit 3

 No change to the recycle pump capacity is required.

BPEI will install agitators on each reaction tank, replacing the existing sparger system, which has a tendency to clog and hinder performance.

Page 3 of 59Unit 1

 Install six (6) agitators on each reactor tank.

Unit 2

 Install five (5) agitat ors on each reactor tank.

Several chemical and reaction ra te modifications were analyze d, namely liquids residence time and solids residence time. Optimum values for each of these reaction rate parameters have been worked into the existing scrubbe r operation by revising current ranges for opera tional level in the reaction tanks, absorber slurry solids ranges, an d limestone grind fineness. Finally the forced oxidation system was evaluated with emphasi s on achieving superior mixing of injected oxidation air, suspension of slurry in the vessel, and comple te oxidation of SO 2 removed by the absorber. The results of this analysis recommend the following operating changes:

Units 1 and 2

 Increase absorber slurry solids from 10-12% to 14-16% RETURN TO ORIGINAL

DESIGN

 Increase absorber reaction tank level fr om 31.5’ to 35.5’ RETURN TO ORIGINAL

DESIGN

Unit 3

 Increase absorber slurry solids from 10-12% to 14-16%

 Increase absorber reaction tank level from 15’ to 18’

Performance – Based on BPEI’s evaluation of th e existing equipment and performance capabilities and the modeling effort described above, it has been de termined that all three units can be expected to achieve the 96% SO 2 removal target. These values are based on a design coal

that has an SO 2 level of 6.3 lb./MMBtu. Also, the result s reflect a plant modification to route the flue gas from Unit 3 to the Unit 4 WFGD, which ha s an absorber with 25 % additional capacity.

Engineering Scope of Work – BPEI will perform engineeri ng activities associ ated with the changes noted above. BPEI will also perform CFD modeling to determ ine the modifications required to the absorber inlet and confirm the spray nozzle layout and coverage area.

Page 4 of 59Procurement Scope of Work – The materials required to m odify the WFGD and achieve the target performance of 96% SO 2 removal efficiency are detailed in the table below:

CASE 2 LIST OF MATERIALS Unit 1 Unit 2 Unit 3

Description Size Qty Units Qty Units Qty Units

Slurry Recycle System

Recycle Pumps 700 HP 3 ea. 3 ea.

Recycle Pumps 800 HP 5 ea. 5 ea.

Recycle Discharge Piping 30" 2000 LF 2000 LF

Recycle Suction Pipe/Flanges 30" 8 ea. 8 ea.

Recycle System Valves and Inline Equipment 30" TBD TBD

Spray Nozzles (double down) 120 o spray 168 ea. 168 ea. 288 ea.

Spray Nozzles (bi-directional) 120 o spray 168 ea. 168 ea. 288 ea.

Wall Baffles

Wall Baffles 4 ea. 4 ea. 8 ea.

Oxidation Air System

Oxidation Air Lances 8" x 40" lg. 6 ea. 6 ea. 10 ea.

Air Lance Supports 6 ea. 6 ea. 10 ea.

Air Piping External to Sump 20" C.S. 1000 LF 1000 LF TBD LF

Air Piping Hangers 59 ea. 59 ea. TBD ea.

Agitators 6 ea. 6 ea. 10 ea.

Construction Plan – Prior to construction BPEI will integrate engineering and fabrication into a detailed fabrication plan. The plan will consider constructability, value engineering, estimating, scheduling, safety, quality, project controls and execution. The objective is to assure that construction is a seamless part of the project delivery.

Following mobilization, BPEI will perform pre- construction activities, including receipt of materials, erection of scaffolding and instal lation of the recycle pump foundations. The remaining activities will be completed during th e outage, which is considered of sufficient duration to complete all of the work. The major work activities include the following:

Units 1 and 2

 Replace existing recycle pumps and piping wi th new recycle pumps and associated piping

 Replace existing spray nozzles with new spray nozzles

 Install new wall baffles at Spray Levels 2 and 3

 Remove existing spargers

 Install new agitators and oxidation air lances, and associated piping

Page 5 of 59Unit 3

 Replace existing spray nozzles with new spray nozzles

 Install new wall baffles at Spray Levels 2 and 3

 Remove existing spargers

 Install new agitators and oxidation air lances, and associated piping

Construction will entail four (4) months of pre-outage activity followed by a 3-week outage.

 The pre-outage construction util izes one (1) shift, ten (10) hours per shift, five (5) days per week.

 The outage construction utilizes two (2) sh ifts, ten (10) hours per shift, six (6) days per week.

Cost – The Rough Order of Magnitude (ROM) estimat e for labor, materials and construction for

each unit is as follows:

Unit 1 - $10,541,512 Unit 2 - $10,632,006 Unit 3 - $14,035,835

Case 3 – System Optimization Upgrade: 98% SO 2 Removal Efficiency

Technical Description – The task objective of Case 3 was to provide to LG&E the most economical, reliable method to obtain 98% SO 2 removal for each of the Mill Creek Units, which considered the maximum attainable performance. BPEI modeled the existing absorber systems on Mill Creek Units 1, 2, and 3 (Unit 3 flue gas to be redirected to existing Unit 4 WFGD system) using proprietary software and data obtain ed from plant personnel to create a realistic baseline performance model. The process parameters were then modified using BPEI’s historical experience.

Spray header layout and nozzle selection are op timized based on the overall absorber shell dimensions for absolute maximum performance based on the existing reactor tower dimensions. For Units 1 & 2, recycle pumps are pushed furthe r and piping is resized for greater flow to increase L/G significantly over the original and 96% removal option.

Unit 3 does not require highe r L/G ratio to maximize SO 2 removal. Spray header spacing is increased and placement is altered to allow for multiple levels of bidirectional nozzles, which have proven to be superior in performance co mpared to down-only nozzles. Spray header layout is altered to provide added spray density and pr event any holes in spray coverage by moving the position of individual no zzles on the headers.

Page 6 of 59Units 1 and 2:

 Move Spray Level 1 from below th e tray to 5’ above the tray

 Space all 4 spray levels 5’ apart

 Stagger spray header layout

 Increase spray density by increasing the numbe r of nozzles per spray level from 42 to 54

 Change Spray Level 1 nozzles from dow n-only to dual-flow, double-down nozzles.

 Change Spray Level 2 nozzles from down-only to dual-flow, up-down nozzles.

 Change Spray Level 3 nozzles from down-only to dual-flow, up-down nozzles.

 Change Spray Level 4 nozzles from dow n-only to dual-flow, double-down nozzles.

 Change interior nozzle spray angle from 80 o to 120 o

 Change wall nozzle spray angle from 80 o to 90 o

 Decrease spray pressure from 10 psig to 8 psig

 Add wall baffles to Spray Levels 2 and 3.

Unit 3

 Move Spray Level 1 from below th e tray to 5’ above the tray

 Space all 4 spray levels 5’ apart

 Stagger spray header layout

 Increase spray density by increasing the numbe r of nozzles per spray level from 36 to 52

 Change Spray Level 1 nozzles from dow n-only to dual-flow, double-down nozzles.

 Change Spray Level 2 nozzles from down-only to dual-flow, up-down nozzles.

 Change Spray Level 3 nozzles from down-only to dual-flow, up-down nozzles.

 Change Spray Level 4 nozzles from dow n-only to dual-flow, double-down nozzles.

 Change wall nozzle spray angle from 120 o to 90 o

 Decrease spray pressure from 10 psig to 8 psig

 Add wall baffles to Spray Levels 2 and 3.

The model was then used to determine the required recycle pump flow to achieve 96% SO 2 removal.

Units 1 and 2

 Increase the recycle pump capacity from all at 600 hp to 3 pumps at 500 hp and 5 pumps at 700 hp resulting in a change to the Liquid-to -Gas (L/G) ratio, from 112 gal/kacf to 144 gal/kacf. The recycle pump capacity change in Units 1 and 2 will alter the Liquid-to-Gas (L/G) ratio. Generally L/G ratio trends with removal rate, therefor e increasing the flow through the recycle pumps and nozzl es corresponds to greater SO 2 removal.

Unit 3

 Replace the recycle pump gear boxes to increase capacity.

Page 7 of 59BPEI will install agitators on each reaction tank, replacing the existing sparger system, which has a tendency to clog and hinder performa nce and add new mist eliminators.

Unit 1

 Install six (6) agitators on each reactor tank.

 Install mist eliminators

Unit 2

 Install five (5) agitat ors on each reactor tank.

 Install mist eliminators

Several chemical and reaction rate modifications were analyzed, namely liquids residence time and solids residence time. Optimum values for each of these reaction rate parameters have been worked into the existing scrubbe r operation by revising current ranges for opera tional level in the reaction tanks, absorber slurry solids ranges, an d limestone grind fineness. Finally the forced oxidation system was evaluated with emphasi s on achieving superior mixing of injected oxidation air, suspension of slurry in the vessel, and comple te oxidation of SO 2 removed by the absorber. The results of this analysis recommend the following operating changes:

Units 1 and 2

 Increase absorber slurry solids from 10-12% to 14-16% RETURN TO ORIGINAL

DESIGN

 Increase absorber reaction tank level fr om 31.5’ to 35.5’ RETURN TO ORIGINAL

DESIGN

Unit 3

 Increase absorber slurry solids from 10-12% to 14-16%

 Increase absorber reaction tank level from 15’ to 18’

Performance – Based on BPEI’s evaluation of th e existing equipment and performance capabilities and the modeling effort described above, it has been de termined that all three units can be expected to achieve the 98% SO 2 removal efficiency These values are based on a design

coal that has an SO 2 level of 6.3 lb./MMBtu. Also, the re sults reflect a plant modification to route the flue gas from Unit 3 to the Unit 4 WF GD, which has an absorber with 25% additional capacity.

Engineering Scope of Work – BPEI will perform engineeri ng activities associ ated with the changes noted above. BPEI will also perform CFD modeling to determ ine the modifications required to the absorber inlet and confirm the spray nozzle layout and coverage area.

Page 8 of 59Procurement Scope of Work – The materials required to m odify the WFGD and achieve the target performance of 98% SO 2 removal efficiency are detailed in the table below:

CASE 3 LIST OF MATERIALS Unit 1 Unit 2 Unit 3

Description Size Qty Units Qty Units Qty Units

Slurry Recycle System

Recycle Pumps 700 HP 3 ea. 3 ea.

Recycle Pumps 800 HP 5 ea. 5 ea.

Gear Boxes 8 ea.

Recycle Discharge Piping 30" TBD LF TBD LF

Recycle Suction Pipe/Flanges 30" 8 ea. 8 ea.

Recycle System Valves and Inline Equipment 30" TBD TBD

Spray Nozzles (double down) 120 o spray 324 ea. 324 ea. 624 ea.

Spray Nozzles (bi-directional) 120 o spray 108 ea. 108 ea. 208 ea.

Spray Headers 8 ea. 8 ea. 16 ea.

Spray Pipe Hangers TBD TBD TBD

Wall Baffles

Wall Baffles 4 ea. 4 ea. 8 ea.

Oxidation Air System

Oxidation Air Lances 8" x 40" lg. 6 ea. 6 ea. 10 ea.

Air Lance Supports 6 ea. 6 ea. 10 ea.

Air Piping External to Sump 20" C.S. 1000 LF 1000 LF TBD LF

Air Piping Hangers 59 ea. 59 ea. TBD ea.

Agitators 6 ea. 6 ea. 10 ea.

Absorber Shell and Ductwork Modifications

Outlet Expansion Joint 88 LF 88 LF TBD

317L Absorber Shell 16,744 sq. ft. 16,744 sq. ft.

Absorber Reheater Section 1 Lot 1 Lot 1 Lot

DV210 Mist Eliminator and Spray Wash System TBD TBD TBD

Construction Plan – Prior to construction BPEI will integrate engineering and fabrication into a detailed fabrication plan. The plan will consider constructability, value engineering, estimating, scheduling, safety, quality, project controls and execution. The objective is to assure that construction is a seamless part of the project delivery.

Following mobilization, BPEI will perform pre- construction activities, including receipt of materials, erection of scaffolding and instal lation of the recycle pump foundations. The remaining activities will be completed during th e outage, which is considered of sufficient duration to complete all of the work. The major work activities include the following:

Page 9 of 59Units 1 and 2

 Replace existing recycle pumps and piping wi th new recycle pumps and associated piping

 Replace existing spray nozzles with new spray nozzles

 Install new wall baffles at Spray Levels 2 and 3

 Remove existing spargers

 Install new agitators and oxidation air lances, and associated piping

 Perform absorber shell and duct modifications

Unit 3

 Replace existing spray nozzles with new spray nozzles

 Install new wall baffles at Spray Levels 2 and 3

 Remove existing spargers

 Install new agitators and oxidation air lances, and associated piping

 Perform absorber shell and duct modifications

Construction will entail six (6) six months of pre-outage activity followed by a 3-week outage.

 The pre-outage construction util izes one (1) shift, ten (10) hours per shift, five (5) days per week.

 The outage construction utiliz es two (2) shifts, ten (10) hours per shift, seven (7) days per week.

Cost – The Rough Order of Magnitude (ROM) estimat e for labor, materials and construction for

each unit is as follows:

Unit 1 - $20,428,467 Unit 2 - $20,567,445 Unit 3 - $32,944,117

Summary

Table 1 summarizes all planned modifications fo r each option analyzed in the feasibility study. Differences between Units 1, 2 and 3 are noted where applicable.

Page 10 of 59Base Case

As Installed Case 2

96% Removal Case 3
Maximum Removal

Spray Header

Location No Change (1 spray header below the tray) No Change All 4 headers installed above the tray spaced 5’
apart Spray Header Arrangement Stacked (As installed) Stacked (As installed) Staggered Layout

Spray Nozzle Layout As installed No Change Increase Spray Density

Type of Spray

Nozzles No Change Level 1: Double-Down Level 2: Up/Down Level 3: Up/Down

Level 4: Double-Down Level 1: Up/Down Level 2: Up/Down Level 3: Up/Down

Level 4: Double-Down

Spray Angle U1&2: All 80 o

U3: All 120 o U1&2&3:Interior: 120 o

Wall: 120 o U1&2&3:Interior: 120 o

Wall: 90 o Spray Pressure 10 psig 10 psig 8 psig

Wall Rings None Installed at Spray

Levels 2 & 3 Installed at Spray Levels

2 & 3 Absorber Tray No Change No Change No Change

Absorber Solids 10-12% 14-16% 14-16%

Absorber Level U1&2: 31.5’

U3:15’ U1&2: 35.5’

U3:18’ U1&2: 35.5’

U3:18’

L/G Ratio U1&2: 112 gal/kacf U3: 151 gal/kacf U1&2: 141 gal/kacf U3: 151 gal/kacf U1&2: 144 gal/kacf U3: 151 gal/kacf

Recycle Pumps U1&2: No Change U3: U4 No Change U1&2: New Pumps and Piping or Alternative U3: No Change U1&2: New Pumps and Piping

U3: New Gear Boxes

Absorber Inlet

Duct No Change Modify, as required, based on modeling Modify, as required, based on modeling

ME/Reheater No Change No Change Remove reheat section and supply ME section

Oxidation Air Blower/Agitators No Change No change to blower. Modify piping to match air lances w/ agitators No change to blower. Modify piping to match air lances w/ agitators

Predicted SO 2 Removal
Performance U1&2: 88% U3: 91% (in U4 abs) 96% +98%

Table 1: Mill Creek Upgrades Summary

Page 11 of 592 BPEI WFGD Technical Features and Benefits

All WFGDs utilize the same fundamental technology for SO 2 absorption. Where BPEI’s design and performance differ from others is in the am ount of power and liquid required to achieve the

maximum SO 2 removal efficiency. BPEI maximizes the contact between the gas and the absorptive liquid by optimizing the design of the spray zone and using wall rings to eliminate “gas sneakage.” This maximizes the utilization of each droplet, while minimizing power consumption from the draft and recycle systems.

BPEI utilizes both co-current a nd counter-current spray nozzles, in addition to absorber wall rings, to continuously achieve high SO 2 removals. This performance has been demonstrated at multiple installations. While many of these com ponents and features are common to open spray tower technologies, the unique design configura tions employed by BPEI provide the ability to reliably produce high removal efficiencies. To identify how BPEI achie ves these results, each of the critical design components is described below:

2.1 Extensive 3-D Modeling Technology

BPEI uses an absorber flue gas inlet configuration that effectively introduces the flue gas to the absorber below the first spray le vel and distributes it uniformly over the entire cross-sectional

area of the absorber. This avoids excessive deposits of so lids in the ‘wet-dry’ zone where the incoming hot gases contact the slurry spray flow.

Hood Location

Spra y Flowin g Down Absorber
Wall and Awa y from Inlet Duct

Inlet Gas Flow

Floor of Inlet

BPEI makes extensive use of 3-D modeling technology. From past experience, BPEI has discovered that physical and/or computational models are an im portant tool in developing the design of WFGD systems. Applic ations of m odeling include:

 The prediction of gas distribution at the abso rber inlet and into the first spray level.

Page 12 of 59 The prediction of recirculation tank agitator performance as it relates to both suspension of

solids and distribution of oxidation air for maximum effectiveness.

 Optimization of gas and spray nozzles drop let distribution and interaction through the

absorber.

Without Droplets Droplets With Droplets

The liquid film resistance in the liquid-to-gas (L /G) interface is the limiting factor that regulates

the rate at which the SO 2 absorption occurs. Beyond the (L/G) ratio, the absorption section of the WFGD system must also be designed to ma ximize the contact between the liquid and the incoming flue gas. High efficiencies are acco mplished by designing the spray zone with dualdirectional, wide-angle, hollow-cone sp ray nozzles. This arrangement provides:

 Excellent liquid distribution over the entire spra y level cross-sectional area, ensuring that all the flue gas is treated.

 A staggered spray pattern from one level to the next, avoiding flue gas ‘laning’ through paths of low liquid flow; i.e., pa ths of least resistance.

 A hydrodynamic ‘ring’ along the absorber wall, formed by the use of high liquid flow, narrower spray angle nozzles around the full perimeter. This ring counters the ‘wall effect’ and ensures that the gas flowing upward along the walls is fully treated. It also reduces the amount of water lost’ by being directly sprayed on the absorber wall.

 A physical wall ring plate, which diverts and mi xes the gas flow at the wall around the full inside perimeter of the absorber.

The advantage BPEI has over other suppliers of dual- flow nozzles and wall rings is the ability to accurately model the performance and minimize the L/G ratio necessary to achieve high SO 2 removal efficiencies.

2.2 Dual Flow Nozzles

The features of dual flow nozzles are as follows:

 Liquid flow is both counter-current and co-cu rrent with respect to gas flow, providing good gas-spray mixing and gas-liquid contact.

 The number of nozzle liquid discharge holes doubles over a down-flow only design, yielding smaller droplet size at same pump po wer, thereby improving performance.

Page 13 of 59 With the ‘hourglass’ shaped spray pattern, the fl ue gas must travel th rough twice the number of slurry spray cones as there are leve ls, insuring better ga s-slurry contact.

 Also, with the hourglass shape the number of spray-to-spray intersect ions between adjacent spray cones is greatly increased. The intersections of adjacent spray cones further enhances

SO 2 removal by:

o Generating small ‘mist’ droplets as the droplets collide, providing increased liquid

surface-to-mass ratio.

o Mixing and reforming droplets, providi ng ‘fresh’ droplet surface for gaseous absorption.

o Increasing the gas-liquid mass transfer at low liquid flow rates, thereby reducing

pump power.

Dual-Flow No zzles

0 200 400 600 800 1000 1200 1400 1600 1800

0 10 20 30 40 50 60

Pressure, psigSauter Mean Diameter,m Droplet size without collision

Smaller droplets as a re sult of collision

70

Page 14 of 59Double-Down Nozzles

2.3 Wall Rings

Features of wall rings are as follows:

 A physical barrier by which untreated gas along th e wall is driven into the spray zone for

treatment.

 Full perimeter coverage with no dire ct spray impact on the ring itself.

 Excellent gas-liquid mixing and re-distribution.

 Low gas side pressure drop.

Outer Spray Nozzles Wall Ring Absorber Wall

Page 15 of 59Wall Rings Installed at Ghent

2.4 Agitators and Oxidation Air System

Side mounted agitators are designed to provide complete dispersion of air and suspension of solids. In order to provide high reliability, thes e systems are designed such that any one of the agitators can be off-line for maintenance while the absorber remains online for operation. The agitator seal between the rotating sh aft and the absorber wall can be replaced with the tank full of slurry, thereby providing a dditional flexibility and mini mal need to drain the tank.

The oxidation air system piping delivers air to each agitator. The agitator slurry flow is towards the center of the tank, slightly off radial and slightly downward. The moving slurry ‘sweeps’ the

Page 16 of 59floor and provides ‘off bottom suspension’; i.e., no accumulation of solids on the tank floor. The slurry reaches the center of the tank in a slightly off radial direction and turns upward in a helical pattern to the slurry surface. It then travels radially outward, turns down at the tank wall and returns to the agitators. This is a long and useful travel path, providing good mixing and a long time for all the chemical reactions to reach completion.

Each agitator is equipped with an oxidation air injection lance. The air exits the end of this lance in the fast moving slurry at th e ‘backwash’ of the agitator. This causes the air to be striped into small bubbles, which follow the slurry flow path. This path, as describe d above, is long and allows time for the oxygen to be absorbed into the slurry.

2.5 Mist Eliminators

DV210 Mist Eliminators (shown in th e photo below) are an alterna tive to traditio nal flat mist eliminator arrangements. The installation of a si ngle layer benefits installation time and requires only one layer of support beam s instead of two. The other advantages of DV210 Mist

Eliminators are:

 Minimal pressure loss

 Good elimination performan ce at medium velocities

 Suitable for retrofit with existing washers

 Provides a higher net face area than any other design

Mist Eliminator System

Page 17 of 592.6 Recycle Pumps

BPEI works with all the major recycle pump supp liers to provide the best fit in terms of:

 Application,

 Reliability

 Power requirements

 Maintenance

 Noise

 Cost

 Delivery

The predominant difference between the major supp liers is the design of wetted elements. Weir pumps have a replaceable natural rubber liner insert with a high chrome iron impeller and throat bushing. The liner is a robust fitted insert that is specifically designed and formulated for WFGD slurry service. Duchting pumps have an iron shell with a cast-in-place liner and impeller made of a composite of silicon carbide grains with an epoxy binder. The GIW pumps are designed with high chrome iron for all wetted surfaces. Each pr oject requires are t horough evaluation of the recycle pump vendors to determine the best fit in the specif ic application.

High-Volume Direct-Drive Recycle Pumps

Page 18 of 593 BASE CASE - Current SO 2 Removal Efficiency

3.1 Technical Summary – Base Case

A thorough understanding of current plant operational characteristics and an accurate baseline model are required to complete a performan ce enhancement study for the Mill Creek WFGD systems. BPEI modeled the existing absorber sy stems on Mill Creek Unit s 1, 2, and 3 (Unit 3 flue gas to be redirected to existing Unit 4 WF GD system) using proprietary software and data obtained from plant personnel to create a realistic baseline performance model. BPEI analyzed performance of the model, alteri ng key variables such as flue gas flow, coal sulfur content, recycle pump flow and pressure, recycle spray no zzle type, nozzle spray a ngles, nozzle coverage,

etc. to determine what modifications to the ex isting systems would provide the most economical reliable performance enhancements for each system. The base model also provides critical feedback to the design engineers to confirm that theories and calculations used in the model are accurate and appropriate as a starting point for performance enhancement using BPEI’s proven techniques.

Absorber Tower “B” Absorber Tow e r “ A ”

Existing WFGD

Reactor Towers

and Internals

(See Fig. 2)

Inlet

Ductwor k

ID Fan Reaction

Tan k

Figure 1: Mill Creek Units 1 & 2, Current

Page 19 of 59Mist Eliminator

Levels 1 & 2 Abandoned

Reheater Section

Perforated plate
installed between

s p ra y level 1 and 2 6’ As-installed, 4 spray levels, down only spray nozzles

4’

5’



### Fl ue G a s Inl et

Figure 2: M ill Creek Units 1 & 2, Current Reactor Tower Arrangement

Page 20 of 593.2 System Description

Flue gas production is directed by means of two ID fans in pa rallel feeding the unit A and B

absorbers.

The absorbers share a single reaction tank. Eigh t recycle pumps four feeding each absorber provide the total slurry from the tank to the absorbers.

Oxidation air is introduced thru a sparger type sy stem. The sparger is arranged as a single header located above the floor introducing air evenly throughout the absorber.

Flue gas vertically moves through each of the f our spray headers. Above the first spray header LG&E has installed a perforated plate or tray for the purpose of providing even flue gas

distribution.

The flue gas exits the absorbers thro ugh the mist eliminators to the stack.

Figure 3: Mill Creek Units 1 & 2

Page 21 of 593.3 Current Process Operation

Discussions held with onsite engi neers and operators as well as re views of historical data were

used to better understand curren t operation of the three absorber units. On average the units burn

a coal with sulfur content of 5.4 lb SO 2 /MBtu. Limestone used in the WFGD process to

neutralize SO 2 is finely ground to 95% pa ssing 325 mesh. The absorber s reliably maintain 90-

92% SO 2 removal by maintaining an absorber slurry pH in the reaction tank of 5.7-5.8. Absorber slurry solids is maintained between 10-12 wt% a nd controlled with a bleed system. An oxidation air sparger ring is desi gned to oxidize the SO 2 removed from the flue gas and maintain agitation

in the reaction tank.

The level in the absorber reaction tanks are contro lled at lower set points compared to original design conditions. The absorber slu rry solid concentration is also controlled at a lower density than is typical for limestone, forced-oxidation we t FGD systems. Reported unreliability of the absorber bleed system to maintain absorber slu rry density resulted in th e reduced density control range. It may also be problematic to maintain absorber slurry solids concentration because of the lack of agitation in the absorber reaction ta nk. Currently the only mixing in the reaction tank is an air sparger ring which has been reported to pl ug up whenever an oxidation air blower trips out of service and slowly plug up over time with re gular operation. The air sparger ring assembly appears to be the highest cause of unreliability in the scrubber process operation. Operating at reduced absorber slurry density and absorber leve ls reduces the liquids and solids retention time in the absorber reaction tank, which may have the following consequences:

 Negative impact on the gypsum quality - smalle r crystal size impacting dewatering operations

 Increase the amount of excess limestone required for SO 2 removal - higher pHs required

to maintain SO 2 removal efficiency

 Reduced Hydrocyclone performance – decr eased solids in the underflow to the dewatering process and increased fraction of gypsum fines removed in the overflow
purge stream

 Flue gas off-gassing between the absorber module and the absorber reaction tank causing

area corrosion issues - no seal is maintained

3.4 Spray Header Arrangement / Spray Nozzle Coverage

The high-flow, hollow-cone spray nozzles currently installed in the absorber are designed to produce small droplets with a high spray pre ssure of 20 psig at a spray angle of 80 o on Units 1 and 2 and a spray pressure of 10 psig at a spray angle of 120 o on Unit 3. Figure 5 shows the spray coverage with the existing spray header and nozzle configuration. As can be seen there is very little spray coverage along the absorber wall and between the absorber nozzles. The four spray headers are identical in layout such that some channe ling of the flue gas through the absorber is likely to occur.

Page 22 of 59Reaction tank

Existing spray header coverage, second layer Plan view from above
Mist Eliminators

Figure 4: M ill Creek Units 1 & 2 Plan View, Base Case

Spray coverage gaps in current
system

Figure 5: M ill Creek Units 1 & 2 Plan View, Base Case

Page 23 of 59BPEI recommends testing the spray nozzle perfor mance of each nozzle type to fully understand the current nozzle performance. This is esp ecially critical for Units 1 and 2 because understanding the improvement in performance between current operation and Case 2 might make the difference between utilizing the existi ng recycle pumps or replacing the recycle pumps.

This is covered in more detail in Section 4.

3.5 Recycle Pump Performance

A generic pump curve was provide d for the recycle pumps installed on Units 1 and 2 absorbers. Nozzle data was provided regarding the total number of spray nozzles, nozzle flow rate, spray angle, and spray pressure. The recycle pump to tal dynamic head (TDH) does not correspond to a spray pressure of 20 psig when recycle pumps and piping were modeled. Instead the spray pressure appears to correspond closer to 10 psig spray nozzles. At the lower supply pressure the nozzle performance in terms of spray angle and droplet size and flow rate will not be at design. Conservative assumptions will have to be made regarding the current pump performance and change in pump performance when changing spray header elevations.

Pump curves were provided for the recycle pumps installed on the future Unit 3 absorbers (currently absorber is treating Unit 4 flue gas) and nozzle data corresponds to the pump performance.

BPEI recommends testing recycle pump perform ance on all three units to fully understand current pump performance. The pump performa nce testing would be similar to what was conducted at Trimble County in terms of measur ing motor amperage, pu mp rpm, pump flow rates, and pressure at each pump suction and disc harge to locate the actual operating point on the pump curve. The data will be used to evaluate the possibility of utilizing the current recycle pumps with dual spray nozzles for high SO 2 removal and determining if new gear boxes on Unit 3 recycle pumps will be a ppropriate for maximum SO 2 removal.

3.6 Absorber Inlet Design

On all units the absorber flue gas inlet is shor ter and has a larger surf ace area than typical for new absorber designs. The length of the absorber inlet is designed to mini mize splash back of absorber slurry into the carbon st eel ductwork. Flue gas velocity in the absorber is controlled with the size of the absorber inlet to evenly dist ribute flue gas prior to the first spray level, to eliminate any reverse flow in the duct, and to main tain the wet/dry interface in the absorber area. Otherwise, a large, shallow absorber inlet may result in corrosion of the ductwork upstream of the absorber. Computational flow modeling will determine if the installed tray offsets the negative impact of the current absorber inlet design or if modifications are required to the absorber inlet. Physical flow modeling is r ecommended at a minimum for Unit 3 since ductwork

would need to be re-routed to Unit 4 absorbers.

Turning vanes, a perforated plate, and modificati ons to the inlet duct at Trimble County are an example of how to optimize flue gas flow thro ugh the absorber and eliminate the potential for

Page 24 of 59reverse flow into the ductwork. Figure 6 shows some of the modi fications completed to Trimble County absorber inlet. These modificatio ns were completed based on CFD modeling.

Original scrubber inlet duct shown in

red . Modifications for improved gas

flow shown in green

.

Elevation view of inlet

duct modifications Plan view of inlet duct

modifications

Figure 6: In let Ductwork Modifi cations at LG&E Trimble County

3.7 Design Basis

Table 2 provides a summary of coal analyses for th e Mill Creek Station. The first set of data is a summary of the average fuel bur ned at Mill Creek in 2009. On av erage Mill Creek burned a coal

with an inlet SO 2 concentration of 5.4 lb/MBt u based on the average coal sulfur content and high heating value. The specified fuel for this study is a design coal similar to what was used for Ghent Station Units 1,3 & 4 and Brown St ation WFGD Systems with an inlet SO 2 concentration of 6.3 lb/MBtu and heating value of 12,500 Btu’ s/lb used to evaluate current absorber performance and absorber performance for Cases 2 and 3. The higher sulfur content is designed to represent future opera tion at Mill Creek Station.

Page 25 of 59Fuel Units 2009 Average Design Coal Ultimate Analysis Carbon (C) wt.% 61.61 60.30 Hydrogen (H) wt.% 4.22 4.50 Oxygen (O 2 ) wt.% 7.01 6.80 Nitrogen (N 2 ) wt.% 1.28 1.17 Sulfur (S) wt.% 3.02 3.47 Chlorine (Cl) wt.% 0.06 0.07 Fluorine (Fl) wt.% 0.01 0.01 Moisture (Water, H 2 O) wt.% 11.43 9.56

Ash wt.% 11.36 14.12

Total wt.% 100.0 100.0

Volatile wt.% 35.68 33.00

Fixed Carbon wt.% 41.54 42.00 Higher Heating Value Btu/lb 11,115 11,000

Inlet SO 2 lb/MBtu 5.4 6.3

Table 2: Summary of Coal Quality

3.8 Predicted Absorber Performance

Absorber performance was predicted using design coal sulfur conditions of 6.3 lb SO 2 /MBtu, assuming no change to Units 1 and 2 absorbers, a nd directing Unit 3 flue gas to Unit 4 absorbers. Approximately 88% removal is pr edicted with the existing absorber configuration for Units 1 and 2. Approximately 91% removal is predicted w ith the existing Unit 4 absorber configuration for Unit 3 flue gas. The higher removal is attributed to the larger recycle pumps.

Figure 7 shows the existing spray level spacing for the three units. The existing spray header layout is also used in the Case 2 evaluation.

3.9 Construction

3.9.1 Construction – BPEI has no construction for the base case.

3.9.2 Schedule – No outage scheduled.

3.9.3 Pricing – No price included.

Page 26 of 594’ 3’4”

5’ 3’ 5”

4’ 10”

Tray 6’

Unit 3 Units 1 & 2

Figure 7: E xisting Spray Header Spacing

Page 27 of 594 CASE 2 - 96% SO 2 Removal Efficiency

4.1 Technical Summary – Case 2

In this section of the report, BPEI’s task objective was to provide to LG&E the most economical, reliable method to obtain 96% SO 2 removal for Mill Creek Units 1, 2 and 3. The process models were taken from the baseline condition and modified using a variety of techniques in several stages. Multiple variables were adjusted by application of BPEI’s experience in WFGD and experimental results from the process model. Nozzle spray angle, type, pressure, flow, and arrangement were fine-tuned to provide optimum spray coverage and droplet distribution while maintaining droplet size for p eak liquid to gas interaction. Addition of wall rings, a BPEI licensed and patent ed technology, was evaluated to improve flue gas distribution and prevent laning of ga s along the perimeter of the vessels. Changes to the Liquid-to-Gas (L/G) ratio were evaluated via changes in recycle pum p flow, pressure, and nozzle flow. Generally L/G

ratio trends with removal rate , therefore increasing the flow through the recycle pumps and nozzles corresponds to greater SO 2 removal. Several chemical and reaction rate modifications were analyzed, namely liquids residence time and solids residence time. Optimum values for

each of these reaction rate parameters have been worked into the existing scrubber operation by revising current ranges for operational level in th e reaction tanks, absorber slurry solids ranges, and limestone grind fineness. Finally the forced oxidation system was evaluated with emphasis on achieving superior mixing of in jected oxidation air, suspension of slurry in the vessel, and complete oxidation of SO 2 removed by the absorber. A summary of the planned modifications respective to each vessel is shown on Table 1.

Page 28 of 59120 Degree Spray Nozzles Throughout

Wall Rings
installed at
Level 2 & 3 spray header

elevation

Side mount Agitators with
Oxidation Air
Lances for

enhanced mixing and

oxidation Level 1 & 4 –

Double-Down Spray Nozzles
Level 2 & 3 – Up/Down Spray

Nozzles

Figure 9: M ill Creek Units 1&2, Case 2 Upgrades

4.2 Case 2 – Work Scope

The Case 2 work scope consists of the following:

 Type of spray nozzles – up/down & double down.

 Spray angle – changed.

 Wall Rings – installed at spray levels 2 & 3.

 Recycle pumps – Unit 1 & 2 new pumps, Unit 3 no change.

 Side mounted agitators w ith oxidation air lances.

4.3 Spray Header Arrangement / Spray Nozzle Coverage

Spray nozzle coverage can be significantly impr oved utilizing wider spray angle nozzles on the existing spray header arrangement. Spray nozzle coverage more than doubles by utilizing wider spray angle nozzles on Units 1 and 2. The nozzl e coverage doubles by increasing the nozzles spray angle to 120 deg. from the existing 80 de g. nozzles. Utilizing dual-flow nozzles on all three units produces an even larger surface area. Dual-orifice spray nozzles increase the number

Page 29 of 59of droplets and the number of droplet collisions. Increasing th e number of droplet collisions results in smaller droplets and a significant improvement in SO 2 removal efficiency because the

area available for SO 2 absorption has been increased. Spra y level 1 will util ize double-downward nozzles since this spray header is located just below the tra y. Dual direction nozzles proposed for spray levels 2 and 3 also have additional benefit of increasing the number of collisions and increasing the residence time of droplets in the absorber. Spray level 4 utilizes double-downward nozzles to minimize carryover into the mist elim inator section. Figure 10 is example of a bidirectional spray nozzle being tested.

BPEI proposes increasing the spray angle from 80 o to 120 o on Units 1 and 2. Figures 11, 12, and 13 show the additional coverage achieved with the dual flow nozzles.

Figure 10: Bi-directional spray nozzle testing

Page 30 of 59Figure 11: Mill Creek Units 1 & 2, Case 2 Elevation View Dual flow

nozzles installed

on levels 2 & 3 Original header and perforated
tray Mist Eliminators

Wall Rings

insta lled at levels

2 and 3

Double-down spray

nozzles installed on

level 1 Double-down spray

nozzles installed on

level 4

Flue Gas Inlet Duct

Page 31 of 59Overall view with 120 degree spray nozzles

Figure 12: Mill Creek Units 1 & 2 Plan View , Case 2 Upgrades

Gaps in spray coverage eliminated by wide-angle

nozzles. Additional

droplet collisions

further enhance SO 2 removal Wall Ring

shown in

Blue

Figure 13: Mill Creek Units 1 & 2 Plan View , Case 2 Upgrades

Page 32 of 59120 Degree nozzles,

double down on levels 1 & 4, dual

flow on levels 2 & 3 Spray Headers

Absorber Agitators and

Oxidation A ir Lance s

Figure 14: Mill Creek Units 1 & 2 Elevation View , Case 2 Upgrades

4.4 Wall Rings

There is a physical limit to the degree of sp ray coverage along the wall of the absorbers especially in the corners of squa re reactor modules. Increased flue gas flow is expected along the

wall because of the decreased resi stance from this reduced coverage . BPEI will add wall rings to deflect flue gas from the absorber wall into the in terior of the absorber where there is a greater chance of interaction with recycle spray droplet s. This also promotes more thorough mixing of the flue gas, ensuring no areas of high SO 2 concentration along the walls are allowed to bypass the effective spray zones. Figure 15 below show s a typical wall ring installation in a circular,

tile-lined vessel.

Page 33 of 59Typical wall ring arrangement (circular vessel shown)

Recycle spray nozzle

Flue gas is forced away from the vessel wall, back towards the interior where it is more likely to have liquid to gas interaction, increasing SO 2 removal efficiency Recycle Spray Header

and vessel flan g e

Figure 15: Typical Wall Ring Arrangement (Ghent Plant)

W all rings will be added at spray levels 2 and 3 to maximize the benefit of contacting flue gas with the slurry spray while minimizing the impact on pressure drop across the absorber. Preliminarily, the pressure drop increase is expected to be minimal. Figure(s) 16 is a graphic representation of the wall rings prop osed for Mill Creek absorbers.

Wall Ring: typically

corrosion resistant alloy construction

Figure 16: Proposed Wall Ri ng, typical a rrangement

Page 34 of 59Dual-flow

nozzles installed

on levels 2 & 3

Original header and perforated
tray Wall Rings

installed at levels

2 and 3 Mist

Eliminators

Double-down spray nozzles

installed on levels

1 & 4

Figure 17: Mill Creek Unit 3 El evation View , Case 2 Upgrades

4.5 Liquid-to-Gas Ratio

The Liquid-to-Gas Ratio (L/G) is a sizing criteria for absorber s that compares the slurry recirculation rate to the flue gas flow rate. Pres ently the L/G ratio for Units 1 and 2 is estimated to fall between 112 gal/kacf and 129 gal/kacf base d on available recycle pu mp data. The L/G of 112 gal/kacf assumes a design flue gas flow rate based on Ghent and Brown flue gas flow rates and scaled down for Mill Creek Units 1 and 2. This flue gas flow rate results in a gas velocity through the absorber of 15.5 ft/sec which is close to what plan t personal reported for these units. The higher L/G ratio of 129 gal/kacf is calculated when the original absorber design flue gas

flow rates are modeled. The reduced flue gas flow rate results in a reduced flue ga s velocity of 13.3 ft/sec through the absorber. For the purpose of this study, the worst-case high flue gas flow

rates/reduced L/G ratios were used to evaluate improvements to these units.

Page 35 of 59The L/G ratio for Unit 3 is 153 gal/kacf. There is more data available for Unit 3 flue gas flow rates as a result of baseline testing completed on Unit 3. Unit 4 absorber cross-sectional area is approximately 23% greater than the original Unit 3 absorbers and as a resu lt the flue gas velocity is reduced compared to Units 1 and 2 at 10.8 ft/sec (versus the orig inal flue gas velocity of 13.4 ft/sec through the existing Unit 3 absorbers). The higher L/G is also a result of the higher recycle pump flow rates for the current Unit 4/future Unit 3 absorber. The design ba sis for the flue gas is summarized in Appendix Basis of Design Description.

The units were modeled with the dual spray nozzles and wall rings installed. Unit 3 is expected to achieve 96% removal provided other process issues are addressed as discussed in the following sections. Units 1 and 2 will require a higher L/G ratio of 141 gal/kacf to achieve 96% removal. The higher L/G ratio is equivalent to a pump flow rate of 19,000 gpm requiring new recycle pumps to be able to achieve 96% removal. The slurry velocity through the recycle piping for Units 1 and 2 is already 50% higher than wh at BPEI would recommend to minimize erosion issues. Utilizing higher flow pumps would also require re placing the recycle piping, pump isolation valves, and larger spray headers. Th e higher pump flow rate will also increase the pressure drop across the absorber and impact ID fan performance. This is why a thorough understanding of the existing recycle pump and spray nozzle performance through physical testing is required to determ ine if this is necessary.

In addition, more cost effective opt ions are available as an alternative to replacing recycle pumps
to achieve 96% SO 2 removal on Units 1 and 2. Alternativ e options include utilizing limestone slurry with a finer grind and the addition of orga nic acid to these absorbers. Either of these options will increase SO 2 removal efficiency without a ne gative impact on current absorber layout and ID fan performance. The absorber de sign is not very far off from making the 96% removal mark based on current absorber perfor mance. While replacing recycle pumps may be

desirable to achieve maximum removal efficien cy with these absorbers. BPEI recommends maximizing SO 2 removal in Unit 1 and 2 absorbers with modifications of dual-flow nozzles and wall rings and then making process cha nges if necessary to achieve 96% SO 2 removal.

4.6 Absorber Solids/Liquid Residence Time

As previously mentioned the WFGD systems at Mill Creek are normally operated at reduced slurry solids concentration and reduced reaction tank levels compared to original design set points. These operating conditions coupled with higher inlet SO 2 concentrations and higher SO 2 removals to be considered for this retrofit reduces the solids and liquid residence time in the absorbers. New limestone, forced-oxidized abso rber systems are traditionally designed to

maintain a solids residence time of 15 hours a nd a liquid residence time of 5 minutes. Solids residence time is necessary to provide adequate time in the reaction tank for gypsum crystal growth. The purpose of liquid residence time is to minimize the amount of excess limestone required to maintain SO 2 removal by allowing adequate time for the limestone to dissolve. This is especially important in the production of wa llboard grade gypsum. Five minutes is standard liquid residence time for the limestone grind fine ness and the limestone reactivity typical of limestone used at Mill Creek. In retrofit projec ts BPEI tries to maintain at minimum 12 hours solids residence time and 4.5 minutes liquid reside nce time. The absorber trays are designed to

Page 36 of 59add to the liquid residence time because of slur ry holdup on the tray itself. However, BPEI does

not have data available to evaluate the benefit of the tray on liquid residence time.

Unit 1 and 2 reaction tanks are ap propriately sized. At the reduced solids density and reduced tank levels the solids residence time is 15.1 hours and the liquid residence time 7.0 minutes. At minimum BPEI recommends increasing the reacti on tank level set poin t from 31.5’ to the original design level of 35.5’ to maintain a liquid seal between the absorber modules and the

reaction tanks and eliminate th e potential for flue gas corrosion above the reaction tank. There

are several other areas in inle t and outlet ductwork where flue gas leakage is occurring. The corrosion and gas leakage issues ar e not discussed in this report.

Unit 3 reaction tanks are very small and were originally designed for a lime-slurry, naturaloxidation process. Lime slurry has a faster diss olution rate compared to limestone slurry so reaction tanks are normally de signed with reduced liquid resi dence times. Also, higher solids residence times did not improve the dewateri ng properties of calcium sulfite hemi-hydrate crystals. Even though Unit 3 is a la rger unit compared to Units 1 or 2 (425 MW vs 330 MW), the
total reaction tank volume is 25% less than Unit s 1 and 2 reaction tank volumes. At the reduced solids density and reduced tank levels the soli ds residence time is 8.3 hours and the liquid

residence time 3.2 minutes. BPEI recommends in creasing the reaction tank level set point from 15’ to original design level of 18’ to increase these residence times and to maintain a liquid seal

between the absorber modul es and the reaction tanks.

BPEI also recommends improving the reliability of the absorber bleed system so that absorber slurry density can be maintained within controlled limits. Improvi ng the reliability of the bleed system requires an evaluation of the bleed control valv es and bleed logic. Brown has a similar bleed system design as Mill Creek with a Hydrocyclone assembly installed at the absorber. This system operates with high reliability and BPEI belie ves the reliability of the bleed system at Mill Creek can be improved to maintain a solids concentration approximately 15 wt%, which is typical of limestone forced-oxi dation systems. Increasing the reaction tank level and absorber slurry solids increases the solids residence time to 13.8 hours and the liquid residence time to 3.8

minutes.

The liquid residence time is still below minimu m recommendations for this process. The negative impact is increased excess limestone requi red (higher absorber slurry pH) to maintain

SO 2 removal. The absorber tray may eliminate th is issue however alternatives to increasing liquid residence time were evaluated. One way to increase liquid residence time is to increase the

volume of the reaction tanks. This is a less desirable solution and would require changing the geometry of the transition from absorber to the reaction tank and incr easing the level of the reaction tank. Additionally, liquid residence time can be increased by reducing recycle pump flow to 25,000 gpm. As a result SO 2 removal will be close but may not necessarily be maintained at 96%. Reducing pump flow rates will also require modifications to the recycle pump impellers. Alternatively, limestone grind fineness can be incr eased to offset the decreased liquid residence time. This option will be discussed in mo re detail in Section 5 of this report.

Page 37 of 594.7 Oxidation Air Blowers and Agitators

Poor mixing of air and absorber slurry can reduc e the performance of the absorber. The oxidation air sparger ring currently insta lled requires higher oxygen to SO 2 (O:SO 2 ) ratios to provide enough excess air to comple te the reaction of SO 2 removed by the absorber to gypsum. The air sparger ring is also a source of high unreliability in the absorber system causing forced unit outages whenever the oxidation air system is out of service greater than 30 minutes or the sparger ring plugs up over time. BPEI recommends adding agitator and air lance assemblies

which will reduce the O:SO 2 requirements, increase agitation in the absorber allowing the

absorber to be maintain ed at design solids conc entration, improve reactiv ity by decreasing excess limestone in the absorber, and most importan tly improve reliability of the WFGD system.

Oxidation air lances will be between 8” and 10” in diameter, which will eliminate issues with pluggage even if the oxidation air blower is out of service for several hours. Figures 18 and 19 show graphically agitators and oxidation air lances on one of the reaction tanks. The agitators will be appropriately spaced from the recycle pump s to avoid entraining air in the recycle pump suction and causing cavitation issues. The number a nd size of agitators and air lances required is

a function of the reaction tank diam eter, absorber slurry level in the reaction tank, and volume of oxidation air required to maintain full oxidation.

Plan view of Absorber Agitators and OA Lances showing radial distribution

on Absorber Tank Wall

Figure 18: Mill Creek Units 1 & 2 Plan View , Case 2 Upgrades Absorber Agitators: Completely suspend

slurry solids and disperse oxidation

air for forced
oxidation of >99%

Sulfites Oxidation Air Lance: Injects air directly in front of agitator impeller for maximum dispersion

Page 38 of 59Agitator Mechanical

Seal

, Vessel Penetratio n Side Mounted Absorber Agitator Oxidation Air Injection Lances (One paired with each agitator)

Figure 19: Absorber Agitator/Lance

Oxidation air rates required for the high sulfur, high SO 2 removal on Units 1 and 2 is 10,300 scfm with a supply pressure of 14.6 psig per unit. At present conditions th e oxidation air blowers

run at minimum levels to maintain the airflo w necessary for high oxidation. Oxidation air is provided to Units 1 and 2 with a common blower. Based on present blower operation and the air compressor size (Atlas Copco HA10) it is believed the existing blowers can be used with the new agitator/lance design. The oxidation air rate required for Unit 3 is 14,000 scfm with a supply pressure of 7.2 psig. Unit 3 oxidation air is pr ovided by a dedicated blower. The existing air compressor is capable of maintaining adequate airflow for Unit 3 with the blower operating at minimum load. However, with the relatively sh ort reaction tank levels the blower discharge pressure is relatively low. The piping system ma y require an orifice to keep the air compressor operating on its curve.

Page 39 of 59Figure 20: Oxidation Air La nce and Agitator Impeller

Additional modeling is recommended to verify mixing and ensure the oxidation air can be dispersed in the reaction tanks to complete oxidation. Unit 3 may require a higher O:SO 2 ratio than is typical for WFGDs but preliminarily the blower appears to have the capacity to accommodate higher air flows if necessary.

4.8 Construction

The Case 2 construction will consist of replacing the unit 1&2 recycle pumps and piping to the spray headers unit 3 will not be changed. BPEI will be adding spray nozzles, wall rings and agitators to units 1,2 &3.

BPEI is planning to work four months at 1-10 -5 shifting to install r ecycle pump foundations on

units 1&2 and receive materials and se t up scaffolding for the outage work.

During the three week outage BPEI will replace the recycle pumps and pipes on units 1&2 only. The unit 3 recycle pumps and pipes will not be ch anged out. All three units will have wall rings, spray nozzles and agitators added.

The ROM estimate for BPEI to provide engineer ing, materials and construction is as follows:

o Case 2: Unit 1 - $10,541,512

o Case 2: Unit 2 - $10,632,006

o Case 2: Unit 3 - $14,035,835

Page 40 of 594.9 Schedule

Our preliminary schedule included in the at tachments section is based on the following:

Case 2: Units 1, 2, & 3:4

- (4) Month construction sc hedule working (1-10-5) One shift, ten hours per day for five days

- (3) week outage schedule working (2-10-6) Two shifts, ten hours per shift, six days per week

Page 41 of 595 CASE 3 +98% SO 2 Removal Efficiency

5.1 Technical Summary – Case 3

In the final stage of analysis all available me thods for performance enhancement are brought into play. Spray header layout and noz zle selection are optimized base d on the overall absorber shell dimensions for absolute maximum performance based on the existing reactor tower dimensions. For Units 1 & 2, recycle pumps are pushed furthe r and piping is resized for greater flow to increase L/G significantly over the original and 96% removal option. Unit 3 does not require higher L/G ratio to maximize SO 2 removal. Spray header spacing is increased and placement is altered to allow for multiple levels of bidirecti onal nozzles, which have proven to be superior in performance compared to down-only nozzles. Spra y header layout is altered to provide added spray density and prevent any holes in spray coverage by moving the position of individual

nozzles on the headers.

5’

5’

5’ Perforated

Tra y

Figure 21: Mill Creek Unit s 1 and 2, Case 3 Upgrades

Page 42 of 59Wall Rings

installed at

levels 2 and 3 Absorber

Inlet

Duct

Figure 22: Mill Creek Unit 3, Case 3 Upgrades

Che mical changes including addition of an orga nic acid and increasing limestone grind fineness are considered as additional methods to impr ove the removal reaction rate. Finalizing the maximum removal upgrade options is a series of recommendations for process optimization involving control hardware and logic modificati ons. Over many iterations of design and control philosophy BPEI has refined WFGD control logic to provide to our clients a simple and efficient means of reliably removing SO 2 from flue gas. Modifications to the existing control scheme and potential hardware changes are a ddressed in this final section.

5.2 Case 3 – Scope of work

The Case 3 work scope consists of the following:

 Spray header location – All four header s above the tray spaced 5’ apart.

 Spray header arrangement – Staggered layout.

 Spray nozzle layout – Increase spray density.

 Type of spray nozzles – up/down & double down.

Page 43 of 59 Spray angle – changed.

 Wall Rings – installed at spray levels 2 & 3.

 Side mounted agitators w ith oxidation air lances

 Recycle pumps – U1&2: new pumps, U3: new gearboxes.

 Mist eliminator – Install new DV210.

5.3 Optimization of Absorber General Arrangement

The current arrangement of the tray and spra y headers is less than optimal for maximum SO 2 removal. The spray headers are spaced closely t ogether and the tray is currently installed between spray levels 1 and 2 eliminating the use of dual-flow bi-directional spray nozzles on the first spray level. Additionally, the nozzle arrang ement is identical between spray levels which can result in flue gas channeling (“laning”) through the absorber, reducing SO 2 removal potential. BPEI proposes the following to maximize SO 2 removal efficiency across the absorber:

 Relocate bottom spray header above the perforated tray

 Space the spray levels 5 ft apart

 Stagger nozzle layout between spray levels

 Increase spray density

Originally trays were installed in open spray towe rs with a spray header installed below the tray to quench the flue gas and minimize scaling on the tray. This was especia lly an issue on natural oxidation systems. Research has since been comp leted to demonstrate a quench spray header is not necessary for limestone, forced-oxidation syst ems. BPEI proposes leav ing the inst alled tray in its existing location and rearra nging the spray headers so that they are all located above the tray. Relocating the first spray header will also allow the use of dual-fl ow, bi-directional spray nozzles on an additional spray header.

Spray Header Spacing

 The spray headers will be relocated 5 ft ap art to match current design practices for high efficiency absorbers.

 To create the extra space required in the spray zone section, BPEI proposes removing the abandoned re-heater section and relocating the mist eliminator section

in this unused section.

 Moving the spray headers in this manner al lows the use of bi-directional nozzles on all but the top level spray header. Further, this spray header spacing provides for a providing more uniform distribut ion of slurry to the entire spray zone with enhanced droplet formation for more intimate contact between SO 2 molecules and slurry droplets.

Figures 22 through 26 show the original and pro posed spray header spacing for Units 1 and 2

and Unit 3.

Page 44 of 59Existing spray header spacing. Modified spray header spacing. ME System moved up into abandoned

reheater section

Tray remains at present elevation

Figure 23: Units 1 and 2 Mo dified Elevation View

Figure 24: Units 1 and 2 Spray Head er Spacing simplified sketch

Page 45 of 59ME System moved up into abandoned

reheater section

Modified spray header spacing. Existing spray header spacing.

Figure 25: Unit 3 Modified Elevation View

Figure 26: Unit 3 Spray Header S pacing simplified sketch

Page 46 of 59Staggered Nozzle Layout & Increased Spray Density

 Staggering the nozzle layout between spray headers minimizes the potential of gas channeling or ‘laning’ through pa ths of low liquid flow, i.e. paths of least resistance.

 Wall Rings along the full inner perimeter of the vessel counteract the ‘wall effect’ ensuring that the gas flowing upward along th e walls is fully trea ted and reduces the amount of ‘lost’ slurry that is sprayed onto the wall by redirecting that slurry out into the spray zone.

 Good liquid distribution over the entire spray level cross-s ection ensures all flue gas that passes through the absorber is treated.

 On smaller absorbers with a standard nozzle layout as Mill Creek the flow rate per nozzle is higher than typica l for high efficiency scrubb er designs therefore to maintain a small droplet profile with high fl ow nozzles requires increasing the spray pressure, resulting in a higher TDH for the recycle pumps.

 Alternately, increasing the number of spray noz zles per spray header , thus increasing spray density, is the most effective use of the low spray pressure nozzles proposed for the Mill Creek upgrade.

 Increasing the spray density has the potenti al additional benefits of increasing the removal of particulate and aci d gas (SO3) in the absorber.

Nozzle placement is

now staggered to provide full coverage of flue gas and preventing laning.

Wall rings

Figure 27: Unit 3 Modified Spray Header Layout

Page 47 of 59Plan View Wall Ring

Nozzle density

is increased from 42 per level to 54 per

level Elevation View Nozzle coverage has been modified to provide

m aximum overlap in the

spray zone.

Down only, dual-flow

nozzles on level 4

Wall Rin g s

Bi-directional nozzles

on level 1

, 2 and 3

Figure 28: Mill Creek Units 1 & 2 Modified Nozz le Arrangement

Page 48 of 59Spray headers

are now staggered to provide better

spray coverage

Spray Header

Level 1

Spray Header

Level 2

Spray Header

Level 3

Spray Header

Level 4

Perforated Tray

Figure 29: Mill Creek Unit 3 Modified Nozz le Arrangement

Page 49 of 59Figures 30 and 31 are Process Fl ow Diagrams with the new spray header layout for Units 1

and 2 and Unit 3.

Figure 30: Unit 1 Process Flow Diagram

Page 50 of 59Figure 31: Unit 3 Process Flow Diagram

Optimization of Absorber Process Conditions

The units were modeled with the above refere nced spray header arrangement modifications. The recycle pump curves were used to estim ate pump performance w ith the increased TDH (from the higher spray level elev ation). Utilizing the existing recycle pumps for Units 1 and 2, the decreased pump flow rate with the ne w TDH is approximately 12,000 gpm, decreasing the L/G ratio to 89 gal/kacf. SO 2 removal efficiency is predicted to drop below 95% with the high sulfur coal. To achieve +98% SO 2 removal the existing recycle pumps will have to be replaced with pumps that can achieve 19,400 gpm flow which results in a L/G ratio of 144 gal/kacf. An additional case was considered l eaving recycle spray levels 2 through 4 in the present location and only relocating spray head er 1 to the top of the absorber area. To
achieve 98+% SO 2 removal with the overall spray height reduced 2 ft requires increasing the L/G ratio from 144 to 151 gal/kacf.

Page 51 of 59Utilizing Unit 4 recycle pumps for Unit 3, the d ecreased pump flow rate with the new TDH is approximately 24,000 gpm (12,000 gpm/header), decreasing the L/G ratio to 134 gal/kacf. High SO 2 removal efficiency (>97%) is still predicted for this operating case. However, to

maximize SO 2 removal potential, BPEI recommends increasing the recycle pump flow to the current rate of 27,500 gpm, returning the L/G ratio to 151 gal/kacf. Preliminary review of the Unit 3 recycle pumps indicates it may be possibl e to maintain the pump capacity to operate at the higher TDH by utilizing new gear boxes. A liquid residence time of 4.2 minutes is calculated for Unit 3 at this L/G ratio. Options av ailable to address issues with the decreased residence time include using lime stone slurry with a finer grind or adding organic acid to the process. These options are discussed in more detail below. The addi tional liquid residence typically achieved with the use of a tray should be enough to offset the physical limits of the

reaction tanks.

An additional case was considered leaving recycle spray levels 2 through 4 in the present location and only relocating spray header 1 to the top of the absorber area. The distance between spray headers on Unit 3 absorbers are much shorter (~3.5 ft apart) compared to
Units 1 and 2. To achieve 98+% SO 2 removal with the overall spray height reduced 6 ft requires increasing the L/G ratio from 151 to 174 gal/kacf. It may be possible to still utilize the recycle pumps util izing new gear boxes and possibly im pellers, however the higher L/G has a negative impact on liquid residence time. The residence time is reduced to 3.6 minutes which may or may not be offset with the abso rber tray and chemical adjustments such as finer ground limestone slurry or the addition of organic acid. The reduc ed spray height also impacts the benefits of th e dual-dual flow nozzles.

The overall recycle pump flow rate does not change on Unit 3. The recycle piping is 36” in diameter. The slurry velocity of 8.7 ft/sec is w ithin the limits of 5 to 10 ft/sec recommended by BPEI. When the recycle piping splits between the two absorbers the slurry velocity
increases to 9.8 ft/sec. No modifications to the recycle piping is anticipated.

The required recycle pump flow rate increas es 30% for Units 1 an d 2. The recycle piping diameter is 20”. The line velocity with the curr ent recycle pump flow is already high at 15 ft/sec . High slurry velocities will result in incr eased erosion of the recycle piping especially in piping bends. It is recommended to increase th e recycle piping diameter to 30” to bring the slurry velocity down to 9 ft/sec with the higher pump flows. The three branches at each spray

level will increase from 14” to 18” to maintain slurry velocity. These modifications also require replacing the recycle pum p suction valves and installing new nozzles on the absorber recycle tank for the larger pump suctions. Since recycle piping and headers require modification there is no benefit leaving spray le vels 2 through 4 in th eir present location but proceeding with maintaining the optimal spray h eader distance of 5 ft between spray headers

to maximize SO 2 removal.

The new pump flow rates will also increase th e pressure drop across the absorbers impacting ID fan performance. Based on conversations with plant personal, it is understood that the ID fans are already operating at their maximum capac ity and that either ne w ID fans or booster

Page 52 of 59fans are planned to accommodate a future SCR a nd fabric filter for Units 1 and 2. Increase pressure drop across the absorbers to acco mmodate higher L/G ratios for maximum SO 2 removal should be considered in the new fan design. If the planned absorber modifications are to be completed prior to any modifications/additions to the upstream fans there is an alternative option to increase SO 2 removal while minimizing the im pact of absorber pressure drop. This option requires removal of the absorb er tray and increasing the L/G ratio from 144 gal/acf to 172 gal/acf. Further re view to understand the pressure drop across the absorber tray versus maintaining a higher L/G ratio would have to be completed prior to following this recommendation. If the tray is removed from the absorber, the first absorber spray level

would be located at the elevation of the tray and the subsequent spray levels spaced 5 ft apart

from each other.

BPEI recommends adding pressure instrumentat ion on the pump suctions and discharges to monitor pump performance and adding logic to protect the recycle pump s from cavitation if there is a sudden loss of suction pressure. It is also recommended to add control valves to the pump flush water connections a nd pumps drain to incorporate an automatic flush and drain

sequence.

The absorber control logic at Mill Creek controls limestone slurry feed by maintaining an absorber reaction tank pH set point. To maintain high SO 2 removal efficiency and optimize limestone consumption BPEI recommends going to a feed-forward logic loop with feedback trims to control limestone slurry feed to the reaction tanks. Feed-forward logic, calculates limestone slurry ra te based on inlet SO 2 , an SO 2 removal or emissions set point, limestone slurry concentration, and unit load or flue gas flow rate. There are two feedback trims to the calculated limestone slurry feed rate. The first feedback trim looks at the actual SO 2 removal

or emissions rate and adds more limestone sl urry if the unit is under-scrubbing or decreases limestone slurry feed rate if unit is over-scrubbing. The s econd feedback trim looks at reaction tank pH and will override SO 2 trim, if necessary, to ma intain the reaction tank pH between 5 and 6. This type of feed-forward logic allows for tighter control because the limestone slurry feed rate is adjusted as inle t conditions (such as unit load) change instead of a system that is reactive and swinging up and down around the set point. BPEI recommends a review of the absorber control logic and to consider using CEMs instrumentation, if abandoned on the old Unit 3 system, to measure inlet SO 2 on Units 1 and 2.

5.4 Impact of Reagent Grind Size

The limestone grind maintained at Mill Creek is consistently finer th an 95% passing 325 mesh which is the minimum grind BPEI recommends for high SO 2 removal efficiency absorbers. Increasing the limestone grind to greater than 99% passing 325 mesh in creases the rate the

limestone dissolves in the reac tion tank. Increasing the rate of limestone dissolution will offset the short liquid residence time in Unit 3 reactio n tanks. This would only be necessary if the excess limestone required for high SO 2 removal has a negative impact on gypsum quality. In reality if Unit 3 hydrocyclone unde rflow is being mixed with the underflow slurries from the other three operating units, it is unlikely there wi ll be an overall nega tive impact gypsum quality.

Page 53 of 59Finer grind can also be utilized to improve SO 2 removal performance on Units 1 and 2 to achieve 96% removal reliably in place of repl acing recycle pumps for this phase.

Mill Creek is curre ntly looking to increase the capacity of their reag ent preparation system. Producing ultra fine grind limestone slurry results in diminish ed capacity of the reagent preparation system thus increasi ng the power required per ton of limestone processed through the reagent preparation system. This cost can be weighed against the bene fit of maintaining SO 2 removal and/or avoiding a unit de-rate if recycl e pumps have to be ta ken out of service for

maintenance.

5.5 Impact of Organic Acid

An organic acid, sodium formate, is currently a dded to the existing Unit 3 absorber system. Unit 3 reaction tanks are odd shaped with very poor mixing. Because of the poor mixing excess limestone is required to maintain SO 2 removal. The organic acid buffers the pH in the reaction tank reducing the amount of excess limestone required to maintain SO 2 removal and gypsum quality. Organic acid is already piped the new reaction tanks to be used when treating Unit 3 gas. Similar to the benefit of finer ground limestone, the organic acid can be used to offset any negative impact the small reaction tanks may have on liquid residence time or to improve Units 1 and 2 absorber performance in Case 2. Additio nal piping and logic is required to implement organic acid addition to Units 1 and 2.

At other WFGD system organic acid is utilized as a “spare” recycle pump to maintain high SO 2 removal efficiencies if a recycle pump has to be taken out of service. Th e benefit of organic acid over ultra fine grind limestone is that the effect is immediate. There is no turnover of a slurry tank prior to the organic acid imp acting absorber performance.

If there are no permit restrictions on the organi c acid in the water purge from the WFGD system, BPEI recommends completing a cost/benefit analysis of operating with 4 recycle pumps versus adding organic acid and operating with 3 r ecycle pumps in the three absorber units.

5.6 Performance Testing and Modeling

BPEI recommends a standard baseline performan ce test as well as advanced Computational Fluid Dynamics (CFD) and physical modeling of planned modifications. Changes to ductwork (Unit 3 into Unit 4 Scrubber) can result in unforeseen gas dynamics that could be detrimental to the process if the appropriate internal flow control devices are not installed. BPEI makes extensive use of modeling technol ogy retrofit modifications such as those proposed for Mill Creek Generating Station. Some of the appl ications of this m odeling are as follows:

 Prediction of gas distribution at the absorber inlet and into the first spray level

 Prediction of gas distribution a nd slurry spray distribution with in the absorber spray zone, including advanced CFD droplet analysis for enhanced accuracy at predictions of liquidto-gas interaction

Page 54 of 59 Prediction of absorber sump recirculation for agitator performance as it relates to both suspension of solids and distribution of oxidation air for maximum effectiveness

Typical physical models are scaled for geometry and operate at full gas velocity, with the mist eliminators modeled in full scale. For this type of model, BPEI is able to analyze gas flow behavior at the gas inlet, ente ring, within the absorber, leaving the spray zone, and entering and leaving the mist eliminators. The results of thes e model tests are incorporated into the actual absorber design (ductwork layout, spray header layout, nozzle spac ing, etc.) to ensure controlled gas behavior, uniform gas flow, high liquid-gas contact for maxi mum efficiency with installed components, and uniform gas flow to the mist e liminators for consistent mist elimination from the flue gas.

Computational Fluid Dynamics (CFD) is also relied upon for design input. The below model was created to study the effects of retrofitting an additional spray level to an absorber to accommodate the use of higher sulfur coal at high er unit load, while maintaining the same outlet emission. Once again, uniformity of flow for high pe rformance with a low ga s side pressure drop was achieved in the model and then replicated in the actual unit. The plant is E.ON’s Schkopau, and the change was executed on four absorbers at 240MW each.

Figure 32: Sample of CFD Model Output

Gas distribution, as predicted at the absorber inlet, in the sp ray zone, and through the mist eliminators is shown modeled with four spray leve ls in service. The geometry of the added fifth spray level, shown on the right, was tested and confirmed to improve SO 2 efficiency, with no

adverse effect on the exis ting absorber or mist eliminator configuration.

Page 55 of 59A similar approach could be taken to Mill Creek Units 1, 2, and 3 for predictions of gas

distribution with modifications to inlet ductw ork, spray header spacin g, spray header layout, number and type of nozzles. CF D modeling would be especially advantageous on Unit 3 because

of the shift to a different absorber unit and all the ductwork modifications associated with that change.

5.7 Construction

The Case 3 construction will consist of replacing the unit 1&2 recycle pumps, piping and spray headers, unit 3 spray pipes, spray headers and recycle gearboxes will be replaced. BPEI will be adding spray nozzles, wall rings and DV210 mist eliminators on units 1,2 &3.

BPEI is planning to work six months at 1-10-5 shifting to install r ecycle pump foundations on units 1&2 and receive materials and set up scaffo lding for the outage work. The Case 3 outage is based on installing mist eliminator, spray head ers, spray nozzles and wall rings into a new absorber module. This will allow the ground fabric ation of the absorber and internals to take place before the outage.

During a six week outage working 2-10-7 BPEI will replace the recycle pumps on units 1&2 only. On unit 3 BPEI will replace th e recycle gearboxes. All three units will have the absorbers and new internals changed out as modul es to reduce the outage schedule.

The ROM estimate for BPEI to provide engineer ing, materials and construction is as follows:

o Case 3: Unit 1 - $20,428,467

o Case 3: Unit 2 - $20,567,445

o Case 3: Unit 3 - $32,944,117

5.8 Schedule

Our preliminary schedule included in the at tachments section is based on the following:

Case 3: Units 1, 2, & 3:4

- (6) month construction sc hedule working (1-10-5) One shift, ten hours per da y, five days per week

- (6) week outage schedule working (2-10-7) Two shifts, ten hours per shift, seven days per week

Page 56 of 596. Construction Plan

6.1 Organization Overview

Babcock Power Environmental, Inc. has deve loped a preliminary C onstruction Plan that capitalizes on its engineering, pr oduct fabrication, installation, and startup expertise to provide LG&E services with an efficient retrofit design to provide low projec t price and short outage

schedule.

6.2 Execution

Pre-Construction

Upon Notice to proceed BPEI will develop a pre- construction team that will integrate BPEI engineering and fabrication with construction and develop a deta iled design, project plan, and

schedule. We will develop the details for constructability, value engineering, estimating, and scheduling. During this period we will refine our budge ts, safety, quality, project controls, and execution plans to reflect mo re detailed design information. Our objective will be to assure the construction phase in a seam less part of the project delivery method. The integration of our proposal, pre-construction a nd construction teams will facilitate the most effective transfer of ownership and job kno wledge, ensuring project safety and timely completion of construction and startup.

Construction

Following the integrated project schedule, BPEI will mobilize on the Mill Creek site and prepare for the receipt of WFGD components. We will construct the Recycle Pump foundations before the outages begin in order to reduce the outage lengths.

Outage

The duration of the outage on Case 2 or Case 3 is based on work being completed during the construction phase. It is BPEI’s intention to minimize the outage duration to assist LG&E services in keeping the Mill Creek boilers operating.

Page 57 of 597. Budget Price



### LG&E Services Company
Contract No. 501654
Mill Creek FGD Perfor mance Upgrade Study

Budget Engineering, Procurement and Construction Estimate February 15, 2011

Description Engineering Equipment Construction Total

Case 2: Unit 1 $1,922,629 $5,365,667 $3,253,216 $10,541,512

Case 2: Unit 2 $1,922,629 $5,365,667 $3,343,710 $10,632,006

Case 2: Unit 3 $1,922,629 $6,735,206 $5,378,000 $14,035,835

Case 3: Unit 1 $2,949,580 $10,573,006 $6,905,881 $20,428,467

Case 3: Unit 2 $2,949,580 $10,573,006 $7,044,859 $20,567,445

Case 3: Unit 3 $2,949,580 $17,504,859 $12,489,678 $32,944,117

Note: The estimate for the Mill Creek WFGD Study is a ROM (rough order of magnitude) estimate. The accuracy is based on +25% to – 10 %. The pricing is based on current 2011 dollars

with no escalation. The scope of the pricing for the Mill Creek Study is limited to WFGD Performance retrofit improvements. There are no other maintenance upgr ades to the absorber structure or reaction

tank included.

Page 58 of 59Page 59 of 59 8. Project Schedule

Our preliminary schedule included in the at tachments section is based on the following:

Case 2: Units 1, 2, & 3:4

- (4) Month construction sc hedule working (1-10-5) One shift, ten hours per day for five days

- (3) week outage schedule working (2-10-6) Two shifts, ten hours per shift, six days per week

Case 3: Units 1, 2, & 3:4

- (6) month construction sc hedule working (1-10-5) One shift, ten hours per da y, five days per week

- (6) week outage schedule working (2-10-7) Two shifts, ten hours per shift, seven days per weekFlue Gas Desulfurization Design Basis Spreadsheet

100524

Rev. 0 LG&E Energy Mill Creek Units 1, 2, and 3 Kosmodale, KY WFGD Upgrade

Prepared Name Suzette Puski Prepared Date 1/25/11

Checked Name Matt Quitadamo

Checked Date 1/25/2011

Customer Si g ned Name

Customer Si g ned Date

Remarks:

This technical data is proprietary technology of BPEI, Inc. P.O. Box 15040, Worcester, MA 01615-0040, and is submitted, lent and furnished to recipient in strict confidence with the express understanding that the recipient shall not reproduce, copy, loan, dispose of or disclose to anyone outside recipient's organization, directly or indirectly, or use said proprietary material for any purpose other than that for which it is furnished and submitted. Recipient by receiving said proprietary material agrees not to use the same in any way injurious to the interest of BPEI, Inc., and agrees to return same upon request.

Copyright BPEI, Inc. 2011. Project Number:

Revision Number:
Customer Name: Project Name:

Report Title (shown on printed sheets)

Email changes to Location, City, State Description

Date: 2/15/2011 1 of 8FGD Design Basis Spreadsheet Scope of Supply

Plant Name:

Plant Location

U1&U2 Case 2 U3 Case 2 U1&U2 Case 3 U3 3 Case 3
Flue Gas Path

Equipment for Partical Removal Equipment for Draft System

Inlet Duct Modifications xxxx Equipment for SO2 Removal Install Wall Rings on Spray Levels 2 and 3 8 Wall Rings 8 Wall Rings 8 Wall Rings 8 Wall Rings Install Up/Down Interior Spray Nozzles 160 128 336 336 Install Up/Down Interior Wall Ring Nozzles 176 160 312 288 Install Double-Down Interior Spray Nozzles 160 128 112 112 Install Double-Down Wall Ring Spray Nozzles 176 160 104 96 Replace Recycle Pumps 8 Pumps 8 Pumps Replace Recycle Pump Piping x x Replace Recycle Pump Gear Boxes 8 Pumps Add Agitators and Air Lances 12 10 12 10 Equipment for SO3 Removal Equipment for Hg Removal Equipment for NOx Removal Equipment for Mist Removal Replace ME Section w/ DV210 x x
other Waste Water Treatment

Utilities

Reagent Equipment for Reagant Unloading Equipment for Reagent Storage Equipment for Reagent Day Storage Equipment for Reagent Slurry Preparation Increase Limestone Grind Possible Alternative May be Required Organic Acid Equipment for Organic Acid System Add organic feed system to Units 1 and 2 Possible Alternative Byproduct Equipment for Byproduct Treatment Equipment for Byproduct Storage Equipment for Byproduct Loading

Fly Ash Equipment for Flyash Treatment Equipment for Flyash Storage Equipment for Flyash Loading

Balance of Plant Water Supply Service Air Supply Instrument Air Supply Cooling Water Supply

Process Control Evaluate revising control logic for SO2 removal xxxx Electrical Equipment

Structural Steel

Civil

Construction Process Equipment Balance of Plant Equipment Process Control incl. Wiring Electrical Equipment incl. Wiring

Structural Steel

Civil

Commissioning Yes

Performance Test No Mill Creek Units 1, 2, and 3

Rev. 0

Date: 2/15/2011 2 of 8Mill Creek Units 1, 2, and 3

Rev. 0

Plant Data Sheet Units DESIGN

Plant Name: Mill Creek Units 1, 2, and 3

Plant Location Kosmodale, KY

Site Conditions

Seismic Zone (Av/Aa) 0.09/0.07
Design Ambient Temp o F 6 8
Maximum Summer Ambient Temp o F 105 ( per Trimble Count y Desi g n )
Minimum Winter Ambient Temp o F -10 ( per Trimble Count y Desi g n )
Indoor Temperature Design / Range o F
Plant Elevation @ Grade ft 460 Elevation @ Absorber Inlet ft above TOC Units 1 & 2: 39.5, Unit 3: 28.2 Atmospheric Pr. @ Absorber Inlet Elevation psia Units 1 & 2: 14.43, Unit 3: 14.44 Absolute Humidity Average % max 100% Average Rainfall inches/year 50 (per Trimble County Design) Wind Speed CRM 780 section 1611.0 MPH 70 (per Trimble County Design)

Snow Load CMR 780 Section 1610.0 lb/sf 15 (per Trimble County Design) Earthquake Loads CMR 780 Section 1612.0

FGD Operation

Mode Part/Continuous Continuous Months of FGD operation/yr - Design Mon/ yr 12 Months of FGD operation/yr - Future Mon/ yr 12 Number of Boilers served by one Scrubber # Each Unit has a dedicated mult-module absorber system Bypass Operation required Yes / No No B y pass Allowed Equipment Installation Indoor/Outdoor FGD Design Basis Spreadsheet

Date: 2/15/2011 3 of 8Mill Creek Units 1, 2, and 3

Rev. 0

Boiler Data Sheet Units DESIGN

Units 1 & 2 Unit 3

LOAD % MCR 100 100 Nominal Rating MW, Gross 350 410
MW, Net 386

Boiler Manufacturer

- Combustion Engineering Babcock & Wilcox

Fuel Fired Coal/Gas/Oil Coal Coal Firing Method Dry Bot/Wet Bot/Cyclone Opposed Wall Fired Boiler (5x4 high) w/ LNB MCR Steam Flow (Design) pph 2,326,000 3,144,000 Boiler Type Balanced Draft/Pressurized Balanced Draft Balanced Draft Plant Capacity Factor Percent of Year 74.9 Gross/ 73.6 Net Hours of operation per year Hours in 2000 7447 hrs Number of Cold Starts per year Target/Actual 2 actual Number of Hot Restarts per year Target / Actual 22 actual Ignition Fuel Fired Oil/Gas Oil Oil Ignition Fuel Fired Hours/Year 800,000 gal Minimum Load for FGD Operation MWnet 193 MW net

Flue Gas Recirculation Y/N N N

SCR

SCR Reactor - Number Installed N/A 2 Catalyst Type Hitachi Plate

NOx inlet / outlet lbs/Mbtu 0.347 / 0.035 NH3 Slip ppmdv @ ref O2 < 2.0 @ the End of Life

Air Heater

Air Heater - Number Installed

- 2 2 Air Heater Type Rotary/Tubualr Ljungstrom Rotary Ljungstrom Rotary

Air Heater Orientation V-Shaft or H-S V-Shaft V-Shaft Will Air Heater be changed? Y/N & to what? N N Air Heater Surface configuration Model Numbers & Materials 27-VI-63 29-VI-54 Air Heater Cleaning Device

- Steam Soot Blowers Steam Soot Blowers Air Heater Leakage Percent 8 @ as-found condition Baseline Test

ESP

ESP's - Number Installed Number 2 2 ESP Info - Configuration Single layer or Stacked TBD by LG&E

ESP Info - Location Cold or Hot Cold Cold
ESP Dust Loading @ ESP Temp grains/ACF @°F 3.375 @ 300 o F
Dust Loading @ Eco. Out Temp grains/ACF @°F 2.294 @ 648 o F ESP Info - Outlet Dust Loading grains/ACF @°F TBD by LG&E ESP Efficiency % TBD by LG&E

WFGD
WFGD - Original Supplier Name Combustion Engineering American Filter WFGD - Number Absorbers Operating / Installed Number 2 / 2 4 / 4 WFGD Info - Type Single Loop or Double Loop Single Single WFGD Info - Spray Configuration Co-Current or Counter Current Counter Current Counter Current (Co-Current on Level 2) WFGD Info - Spray Level Configuration Operating + Spare 4+0 + Tray 4+0 + Tray WFGD Info - Reagent Lime or Limestone Limestone Limestone WFGD Info - Original Design SO2 Loading lbs/Mbtu 6.3 6.3 WFGD Info - SO2 Removal Efficiency % Phase 1: 96, Phase 2: 98+ Phase 1: 96, Phase 2: 98+

Other Ash Reinjection Yes or No No No Draft System

FD Fan, Existing Number 2 / American Standard (595 rpm @ 110 o F) Design Pressure IWG

Fan HP HP
ID Fan, Existing Number 2/ American Standard (690,000 cfm @ 300 o F) 2 / American Standard (834,950 cfm @ 300 o F) Design Pressure IWG 20 45

Fan HP HP ID Booster Fan, Existing Number N/A N/A Design Pressure IWG N/A N/A

Booster Fan HP HP N/A N/A FGD Design Basis Spreadsheet

Date: 2/15/2011 4 of 8LG&E Mill Creek

Rev. 0

FGD Load Data Sheet Units

Load Name Brown Units 1 & 2 Unit 3 Units 1 & 2 Unit 3

Load MW 750 330 425 330 425 Fuel Flow Rate lb/hr 676,790 148,894 148,894 128,049 95,879 Firing Rate Gross10^6 BTU/Hr 5,400 5,400 5,400 5,400 5,400

Excess Air % 25.0 25.0 21.5 25.0 25.0 In-Leakage % 20.0 20.0 23.5 20.0 20.0 Flue Gas Conditions @ Inlet Scope of Supply Ratio SCR Test Old Mat Bal Ratio Flow Basis per Absorber 1 1 of 2 1 of 4 1 of 2 1 of 4 Flue Gas Flow Rate lbs/h wet 9,676,853 2,128,908 1,418,869 1,832,990 1,370,888 Flue Gas Flow Rate lbs/h dry 9,252,111 2,035,464 1,356,591 1,752,535 1,310,716 Flue Gas Flow Rate scfm wet 1,971,997 433,839 289,144 373,536 279,366 Flue Gas Flow Rate scfm dry 1,830,923 402,803 268,459 346,813 259,381 Flue Gas Flow Rate acfm 3,159,481 695,086 463,259 598,469 447,593 Flue Gas Temperature °F 330 330 313 330 313

Flue Gas Pressure I.W.G. 14.73 14.43 14.44 14.43 14.44 Flue Gas O2 % vol, dry 7.9 7.9 7.9 7.9 7.9 Flue Gas CO2 % vol, dry 11.0 11.0 11.0 11.0 11.0

Flue Gas H2O % vol wet 7.1 7.1 7.1 7.1 7.1 Flue Gas reference O2 % vol dry 6.0 6.0 6.0 6.0 6.0 Flue Gas SO2 *) ppmdv @ act O2 / lbs/MBTu 2,623 / 6.9 2,395 / 6.3 2,395 / 6.3 2,395 / 6.3 2,395 / 6.3 Flue Gas SO3 *) ppmdv @ act O2 / lbs/MBTu 26 8888 Flue Gas HCl *) ppmdv @ act O2 / lbs/MBTu 44 44 44 44 44 Flue Gas HF*) ppmdv @ act O2 / lbs/MBTu 99999 Flue Gas NOx *) ppmdv @ act O2 / lbs/MBTu Flue Gas NH3 *) ppmdv @ act O2 / lbs/MBTu Flue Gas Dust *) grains/ dcfm lbs/MBTU 0.07 / 0.41 0.07 / 0.41 0.07 / 0.41 0.07 / 0.41 0.07 / 0.41 Flue Gas Hg *) ppmdv @ act O2 / lbs/MBTu Flue Gas Cd *) ppmdv @ act O2 / lbs/MBTu Flue Gas Heavy Metals *) ppmdv @ act O2 / lbs/MBTu *) Concentration range is independent of the boiler load Flue Gas Conditions @ outlet Scope of Supply expected values
Flue Gas Flow Rate lbs/h wet 10,356,857 2,278,509 1,518,574 1,961,796 1,467,221 Flue Gas Flow Rate lbs/h dry 8,704,210 1,914,926 1,276,255 1,648,751 1,233,096 Flue Gas Flow Rate scfm wet 2,184,799 480,656 320,346 413,845 309,513 Flue Gas Flow Rate scfm dry 1,861,975 409,635 273,012 352,695 263,780 Flue Gas Flow Rate acfm 2,624,304 577,347 384,789 497,096 371,776 Flue Gas Temperature °F 128 128 128 128 128

Flue Gas Pressure I.W.G. 14.62

Flue Gas O2 % vol wet 11.1 11.1 11.1 11.1 11.1

Flue Gas CO2 % vol wet 88888

Flue Gas H2O % vol wet 14.8 14.8 14.8 14.8 14.8 Flue Gas SO2 *) ppmdv @ act O2 / lbs/MBTu 52 / 0.14 47 / 0.13 47 / 0.13 47 / 0.13 47 / 0.13 Flue Gas SO3 *) ppmdv @ act O2 / lbs/MBTu 82222 Flue Gas HCl *) ppmdv @ act O2 / lbs/MBTu 00000 Flue Gas HF*) ppmdv @ act O2 / lbs/MBTu 00000 Flue Gas NOx *) ppmdv @ act O2 / lbs/MBTu Flue Gas Dust *) grains/ dcfm lbs/MBTU 0.02 / 0.12 0.02 / 0.12 0.02 / 0.12 0.02 / 0.12 0.02 / 0.12 Flue Gas Hg *) ppmdv @ act O2 / lbs/MBTu Flue Gas Cd *) ppmdv @ act O2 / lbs/MBTu Flue Gas Heavy Metals *) ppmdv @ act O2 / lbs/MBTu *) Concentration range is independent of the boiler load FGD Design Basis Spreadsheet

Date: 2/15/2011 5 of 8Coal & Reagent Data Sheet Units Unit 1 & 2 Unit 3 Unit 1 & 2 Unit 3 Design Coal Name Must be filled in

Coal Source: Coal Mine 2009 2009 Date Sample Taken: Date Average Average Design Design Coal Ultimate Analysis As Received
Carbon (C) Wt% 61.61 61.61 60.30 60.30
Hydrogen (H) Wt% 4.22 4.22 4.50 4.50
Oxygen (O 2 ) Wt% 7.01 7.01 6.80 6.80

Nitrogen (N 2 ) Wt% 1.28 1.28 1.17 1.17

Sulfur (S) Wt% 3.02 3.02 3.47 3.47
Chlorine (Cl) Wt% 0.06 0.06 0.07 0.07
Fluorine (Fl) Wt% 0.01 0.01 0.01 0.01
Moisture (Water H 2 O) Wt% 11.43 11.43 9.56 9.56

Ash Wt% 11.36 11.36 14.12 14.12

Total Wt% 100.00 100.00 100.00 100.00

Wt. % Volatile Wt% 35.68 35.68 33.00 33.00

Wt % Fixed Carbon Wt% 41.54 41.54 42.00 42.00
Higher Heating Value Btu/lb, As Recvd 11,115 11,115 11,000 11,000 Reagent Name:

Reagent Source: Date Sample Taken:

Reagent Analysis

CaCO3 wt.%

reactive CaCO3 wt.%

CaO wt.% Ca(OH)2 wt.%

Fe2O3 wt.%

Al2O3 wt.%

SiO2 wt.% MgCO3 wt.% MgO wt.% Mg(OH)2 wt.% Chlorine (Cl) ppm Fluorine (Fl) ppm

Moisture wt%

Inert wt% FGD Design Basis Spreadsheet LG&E Mill Creek

Rev. 0

Date: 2/15/2011 6 of 8Process Water Data Sheet Units Design Min Max

Mist Eliminator Wash Water Analysis

pH

Conductivity mS/m

Total hardness mg/l

Carbonate hardness mg/l

Temperature °F

Suspended solids mg/l

Calcium as Ca 2+ mg/l

Magnesium as Mg 2+ mg/l

Sodium as Na + mg/l

Chloride as Cl - mg/l

Sulphate SO 4 2- mg/l

Sulphite SO 3 2- mg/l

Make-Up Water Analysis

pH

Conductivity mS/m

Total hardness mg/l

Carbonate hardness mg/l

Temperature °F

Suspended solids mg/l

Calcium as Ca 2+ mg/l

Magnesium as Mg 2+ mg/l

Sodium as Na + mg/l

Chloride as Cl - mg/l

Sulphate SO 4 2- mg/l

Sulphite SO 3 2- mg/l

Reclaim Water Analysis

pH

Conductivity mS/m

Total hardness mg/l

Carbonate hardness mg/l

Temperature °F

Suspended solids mg/l

Calcium as Ca 2+ mg/l

Magnesium as Mg 2+ mg/l

Sodium as Na + mg/l

Chloride as Cl - mg/l

Sulphate SO 4 2- mg/l

Sulphite SO 3 2- mg/l

Service Water Analysis

pH

Conductivity mS/m

Total hardness mg/l

Carbonate hardness mg/l

Temperature °F

Suspended solids mg/l

Calcium as Ca 2+ mg/l

Magnesium as Mg 2+ mg/l

Sodium as Na + mg/l

Chloride as Cl - mg/l

Sulphate SO 4 2- mg/l

Sulphite SO 3 2- FGD Design Basis Spreadsheet Mill Creek Units 1, 2, and 3

Rev. 0

Date: 2/15/2011 7 of 8Gypsum Slurry Data Sheet Units U1&2 - Case 2 U1&2 Case 3 U3 Case 2 U3 Case 3

Recycle Slurry Analysis

Mass Flow Rate, per pump lb/hr 10,363,636 10,581,818 15,000,000 15,000,000

Volume Flow rate, per pump gpm 19,000 19,400 27,500 27,500

Estimated TDH

Spray Level 1 ft, H2O 47.3 54.7 56.4 59.7

Spray Level 2 ft, H2O 53.3 59.7 61.2 64.7

Spray Level 3 ft, H2O 58.3 64.7 64.6 69.7

Spray Level 4 ft, H2O 62.3 69.7 68.0 74.7

Specific Gravity 1.08-1.11 1.08-1.11 1.08-1.11 1.08-1.11

Density lb/ft 3 66.8-69.3 66.8-69.3 66.8-69.3 66.8-69.3

Temperature °F 125-135 125-135 125-135 125-135

pH 5 to 6 5 to 6 5 to 6 5 to 6

Chloride as Cl- mg/l 5,000 5,000 5,000 5,000

Viscosity cp 7.00 7.00 7.00 7.00

Solids Content wt.% 14-18 14-18 14-18 14-18

Solids Stream

Gypsum wt.% dry 85-95 85-95 85-95 85-95

Limestone wt.% dry 1-3 1-3 1-3 1-3

Inert wt.% dry 5-15 5-15 5-15 5-15

Special Notes: FGD Design Basis Spreadsheet Mill Creek Units 1, 2, and 3

Rev. 0

Pump TDH calculations are preliminary for cost estimate purposes only Compressed air is injected in the reaction tank to complete oxidation reaction

No Change to existing Unit 3 pumps in Phase 1

## L G & E S e r v i c e s C o m p a n y

C o n t r a c t N o

. 5 0 1 6 5 4

M i l l C r e e k F G D P e r f o r m a n c e U p g r a d e S t u d y



# U n i t s 1 & 2

## L G & E S e r v i c e s C o m p a n y

C o n t r a c t N o

. 5 0 1 6 5 4

M i l l C r e e k F G D P e r f o r m a n c e U p g r a d e S t u d y



# U n i t s 3 & 4Mill Creek Units 1, 2 and 3

Rev. 0

Unit 1 Unit 2 Unit 3

Materials Qty Comments Qty Comments Qty Comments

Recycle Pumps **Replace existing 8 recycle pumps and motors with gear**  **driven centrifugal pumps, 3 at 700 HP, 5 at 800 HP**  **Replace existing 8 recycle pumps and motors with gear**  **driven centrifugal pumps, 3 at 700 HP, 5 at 800 HP No Modifications** 

Recycle Discharge Piping **2000 LF Increase diameter of all**  **external recycle piping to 30" 2000 LF**  **Increase diameter of all external recycle piping to 30" No Modifications** 

Recycle suction pipe/flanges **8 pcs Increase diameter of all**  **external recycle pump suction piping to 30"**  **8 pcs Increase diameter of all**  **external recycle pump suction piping to 30"**  **No Modifications**

Recycle System

Valves and inline equipment **TBD Replacement of all inline**  **equipment in recycle system with 30" Dia. Includes valves,**  **gaskets, replacement bolting, fittings.**  **TBD Replacement of all inline**  **equipment in recycle system with 30" Dia. Includes valves,**  **gaskets, replacement bolting, fittings.**  **No Modifications**

Spray Nozzles **336 Replace all spray nozzles with**  **120 degree spray patter,**

**Levels 1 & 4 will use double down nozzles, Levels 2 & 3**  **will use bi-directional nozzles,**

**all will be bolted connection type to connect to existing**  **spray header, all alloy hardware for bolting.**  **336 Replace all spray nozzles with**  **120 degree spray patter,**

**Levels 1 & 4 will use double down nozzles, Levels 2 & 3**  **will use bi-directional nozzles,**

**all will be bolted connection type to connect to existing**  **spray header, all alloy hardware for bolting.**  **576 Replace all spray nozzles with**  **120 degree spray patter,**

**Levels 1 & 4 will use double down nozzles, Levels 2 & 3**  **will use bi-directional nozzles, all will use victaulic couplings**  **to connect to existing spray header, with alloy pin and bolt**  **on coupling.**

Wall Baffles

Wall Baffles **4 Install 2 Wall Baffles, one at**  **Spray level 2 centerline, one at Spray level 3 centerline,**  **with cutouts as necessary for**

**nozzle installation. 4**  **Install 2 Wall Baffles, one at Spray level 2 centerline, one**  **at Spray level 3 centerline, with cutouts as necessary for** 

**nozzle installation. 8**  **Install 2 Wall Baffles, one at Spray level 2 centerline, one**  **at Spray level 3 centerline, with cutouts as necessary for** 

**nozzle installation.**

Oxidation Air Lances **240 LF Install one Oxidation Air lance**  **per absorber agitator (6 total). Requires new vessel**  **penetration, internal and external supports. 8" Dia**  **Nickel Alloy Piping material. 240 LF**  **Install one Oxidation Air lance per absorber agitator (6 total).**  **Requires new vessel penetration, internal and**  **external supports. 8" Dia Nickel Alloy Piping material.**  **10 pcs Install one Oxidation Air lance**  **per absorber agitator (5 Per absorber sump, 10 total).**  **Requires new vessel penetration, internal and**  **external supports. 8" Dia Nickel Alloy Piping material.** 

Air Lance Supports **6 pcs High Nickel Alloy Material to** 

**be used consistent with process and Stress analysis**  **6 pcs High Nickel Alloy Material to** 

**be used consistent with process and Stress analysis**  **10 pcs High Nickel Alloy Material to** 

**be used consistent with process and Stress analysis** 

Air piping external to

sump **1000 LF Modify existing Oxidation Air**  **Piping external to absorber to accommodate a ring header** 

**for distribution of Oxidation air**

**to all lances. 20" Dia CS Piping material for ring**  **header, down to 8" external feeding each lance.**  **1000 LF Modify existing Oxidation Air**  **Piping external to absorber to accommodate a ring header** 

**for distribution of Oxidation air**

**to all lances. 20" Dia CS Piping material for ring**  **header, down to 8" external feeding each lance.**  **TBD Modify existing Oxidation Air**  **Piping external to absorber to accommodate a ring header** 

**for distribution of Oxidation air**

**to all lances. 20" Dia CS Piping material for ring**  **header, down to 8" external feeding each lance.** 

Air Piping hangers **59 pcs External Oxidation Air pipe**  **supports to be installed on**

**vessel 59 pcs**  **External Oxidation Air pipe supports to be installed on** 

**vessel TBD**  **External Oxidation Air pipe supports to be installed on** 

**vessel**

Agitators **6 Install (6) side mount absorber**  **agitators, new vessel penetration, external supports**  **to grade required for each. Ekato, 2M blades anticipated** 

**for use. 6**  **Install (6) side mount absorber agitators, new vessel**  **penetration, external supports to grade required for each.**  **Ekato, 2M blades anticipated**

**for use. 10**  **Install (5) side mount absorber agitators per sump (10 total),**  **new vessel penetration, external supports to grade**  **required for each. Ekato, 1.6M blades anticipated for** 

**use.** FGD Upgrades - Equipment to be Modified

Slurry Recycle System

Oxidation Air System Case 2

**1 of 3 Date: 2/9/2011** Mill Creek Units 1, 2 and 3

Rev. 0

Unit 1 Unit 2 Unit 3

Materials Qty Comments Qty Comments Qty Comments

Recycle Pumps **8 Replace existing 8 recycle**  **pumps and motors with gear driven centrifugal pumps, 3 at**  **700 HP, 5 at 800 HP 8 Replace existing 8 recycle**  **pumps and motors with gear driven centrifugal pumps, 3 at**  **700 HP, 5 at 800 HP 8**  **Gear Boxes regeared**

Recycle Discharge Piping **2000 LF Increase diameter of all**  **external recycle piping to 30" 2000 LF Increase diameter of all**  **external recycle piping to 30" N/A**

Recycle suction pipe/flanges **8 pcs Increase diameter of all**  **external recycle pump suction piping to 30"**  **8 pcs Increase diameter of all**  **external recycle pump suction piping to 30"**  **No Modifications**

Recycle System

Valves and inline equipment **Replacement of all inline equipment in recycle system**  **with 30" Dia. Includes valves, gaskets, replacement bolting,**  **fittings. Replacement of all inline**  **equipment in recycle system with 30" Dia. Includes valves,**  **gaskets, replacement bolting, fittings.**  **No Modifications**

Spray Nozzles **432 Replace all spray nozzles with**  **120 degree spray patter, Level**

**4 will use double-down nozzles, Levels 1, 2 & 3 will**  **use bi-directional nozzles, all will be bolted connection type**  **to connect to existing spray header, all alloy hardware for**  **bolting. 432**  **Replace all spray nozzles with 120 degree spray patter, Level** 

**4 will use double-down nozzles, Levels 1, 2 & 3 will**  **use bi-directional nozzles, all will be bolted connection type**  **to connect to existing spray header, all alloy hardware for**  **bolting. 832**  **Replace all spray nozzles with 120 degree spray patter, Level** 

**4 will use double-down nozzles, Levels 1, 2 & 3 will**  **use bi-directional nozzles, all will use victaulic couplings to**  **connect to existing spray header, with alloy pin and bolt**  **on coupling.**

Spray Headers **8 Spray headers will be modified**  **by addition of nozzles to each**

**level and relocation of the levels to BPEI specified** 

**elevations above the perforated tray**  **8 Spray headers will be modified**  **by addition of nozzles to each**

**level and relocation of the levels to BPEI specified** 

**elevations above the perforated tray**  **16 Spray headers will be modified**  **by addition of nozzles to each**

**level and relocation of the levels to BPEI specified** 

**elevations above the perforated tray** 

Spray pipe hangers **TBD Additional pipe hangers will be** 

**installed to accommodate the additional nozzles and spray**  **header piping added. TBD**  **Additional pipe hangers will be**

**installed to accommodate the additional nozzles and spray**  **header piping added. TBD**  **Additional pipe hangers will be**

**installed to accommodate the additional nozzles and spray**  **header piping added.**

Wall Baffles **4 Install 2 Wall Baffles, one at**  **Spray level 2 centerline, one at Spray level 3 centerline,**  **with cutouts as necessary for**

**nozzle installation. 4**  **Install 2 Wall Baffles, one at Spray level 2 centerline, one at**  **Spray level 3 centerline, with cutouts as necessary for** 

**nozzle installation. 8**  **Install 2 Wall Baffles, one at Spray level 2 centerline, one at**  **Spray level 3 centerline, with cutouts as necessary for** 

**nozzle installation.**

Oxidation Air Lances **6pcs Install one Oxidation Air lance**  **per absorber agitator (6 total). Requires new vessel**  **penetration, internal and external supports. 8" Dia**  **Nickel Alloy Piping material. 6pcs**  **Install one Oxidation Air lance per absorber agitator (6 total).**  **Requires new vessel penetration, internal and**  **external supports. 8" Dia Nickel Alloy Piping material.**  **10 pcs Install one Oxidation Air lance**  **per absorber agitator (5 Per absorber sump, 10 total).**  **Requires new vessel penetration, internal and**  **external supports. 8" Dia Nickel Alloy Piping material.** 

Air Lance Supports **6 pcs High Nickel Alloy Material to** 

**be used consistent with process and Stress analysis**  **6 pcs High Nickel Alloy Material to be**  **used consistent with process and Stress analysis**  **10 pcs High Nickel Alloy Material to be**  **used consistent with process and Stress analysis** 

Air piping external to

sump **1000 LF Modify existing Oxidation Air**  **Piping external to absorber to accommodate a ring header** 

**for distribution of Oxidation air**

**to all lances. 20" Dia CS Piping material for ring header,**  **down to 8" external feeding**

**each lance. 1000 LF**  **Modify existing Oxidation Air Piping external to absorber to**  **accommodate a ring header for**

**distribution of Oxidation air to all lances. 20" Dia CS Piping**  **material for ring header, down to 8" external feeding each** 

**lance. TBD**  **Modify existing Oxidation Air Piping external to absorber to**  **accommodate a ring header for**

**distribution of Oxidation air to all lances. 20" Dia CS Piping**  **material for ring header, down to 8" external feeding each** 

**lance.**

Air Piping hangers **59 pcs External Oxidation Air pipe**  **supports to be installed on**

**vessel 59 pcs**  **External Oxidation Air pipe supports to be installed on** 

**vessel TBD**  **External Oxidation Air pipe supports to be installed on** 

**vessel** Case 3 FGD Upgrades - Equipment to be Modified

Slurry Recycle System

Oxidation Air System Wall Baffles

**2 of 3 Date: 2/9/2011** Agitators **6 Install (6) side mount absorber**  **agitators, new vessel penetration, external supports**  **to grade required for each. Ekato, 2M blades anticipated** 

**for use. 6**  **Install (6) side mount absorber agitators, new vessel**  **penetration, external supports to grade required for each.**  **Ekato, 2M blades anticipated**

**for use. 10**  **Install (5) side mount absorber agitators per sump (10 total),**  **new vessel penetration, external supports to grade**  **required for each. Ekato, 1.6M blades anticipated for use.** 

Outlet expansion joint **88 lf Outlet Duct Expansion joints**  **will be replaced. 88 lf**  **Outlet Duct Expansion joints will be replaced.**  **TBD Outlet Duct Expansion joints**  **will be replaced.**

317L Absorber shell **16,744 sf Absorber shell will be modified**  **with relocation of Spray Headers. Original**  **penetrations will be filled while**

**new ones are cut. 16,744 sf**  **Absorber shell will be modified with relocation of Spray**  **Headers. Original penetrations**

**will be filled while new ones**

**are cut. Absorber shell will be modified**  **with relocation of Spray Headers. Original penetrations** 

**will be filled while new ones**

**are cut.**

Absorber Reheater

Section **Reheater section will be**

**removed and new ME section will be installed in its place**  **Reheater section will be**

**removed and new ME section will be installed in its place**  **Reheater section will be**

**removed and new ME section will be installed in its place** 

DV 210 Mist Eliminator and spray wash system **TBD In the previous Reheat section** 

**new Munters DV210 modular**

**Mist Eliminator sections will be installed along with new ME**  **wash piping system to supply**

**wash water. TBD**  **In the previous Reheat section**

**new Munters DV210 modular**

**Mist Eliminator sections will be installed along with new ME**  **wash piping system to supply**

**wash water. TBD**  **In the previous Reheat section**

**new Munters DV210 modular**

**Mist Eliminator sections will be installed along with new ME**  **wash piping system to supply**

**wash water.** Absorber Shell and Ductwork Modifications

**3 of 3 Date: 2/9/2011** Rev 0AREAITEM DESCRIPTIONBasicEngrgDetailDesignProcure Fab DeliverErectConsultErectionCommissionTest TrainingA Oxidation Air SystemOxidation Air Compressor By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersOxidation Air Agitators BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIOxidation Air Pressure Relief Valves BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIExternal Headers BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIInternal Lances BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEISpray Nozzles BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIInlet Silencer By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersInlet Filter By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersInstrumentation By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersControl Valves By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersActuated Valves By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersManuel Valves By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersPLC Controls By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersAccess Steel (including handrails, platforms, stairs, flooring, gratingeBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersStructural Steel By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersFoundations By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersElectrical Hoists By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersElectrical Power Supply By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMotor Starters and Control Centers By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMotors low Voltage By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMotors medium Voltage By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersPipes > 2 in incl Support BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIPipes < 2 in incl Support BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIRaceway, Conduit, Pullboxes, Wiring, Cabling (excludes skid equipmBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersRaceway, Conduit, Pullboxes, Wiring, Cabling on Skids By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersHeat Tracing (Freeze Protection) By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersCathodic Protection By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersPlant Electrical and Mechanical Tie-In By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersA Absorber Recycle Pumps SystemLG&E Service CompanyContract No. 501654Mill Creek FGD Performance Upgrade StudyCase 2 : Units 1, 2 & 3:41 of 4Rev 0AREAITEM DESCRIPTIONBasicEngrgDetailDesignProcure Fab DeliverErectConsultErectionCommissionTest TrainingLG&E Service CompanyContract No. 501654Mill Creek FGD Performance Upgrade StudyCase 2 : Units 1, 2 & 3:4Absorber Recycle Pumps incl Gear BoxBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIOil Circulation and CoolersBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIAbsorber Recycle Pipes ExternalBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIAbsorber Recycle Pipes InternalBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIexpansion JointsBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEISpray NozzlesBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIInstrumentationBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIActuated ValvesBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersManuel ValvesBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersPLC ControlsBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIAccess Steel (including handrails, platforms, stairs, flooring, gratingeBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersStructural Steel By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersFoundations BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIElectrical Hoists By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersElectrical Power Supply BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIMotor Starters and Control Centers BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIMotors low Voltage BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIMotors medium Voltage BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIPipes > 2 in incl Support BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIPipes < 2 in incl Support BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIRaceway, Conduit, Pullboxes, Wiring, Cabling (excludes skid equipmBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIRaceway, Conduit, Pullboxes, Wiring, Cabling on Skids BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIHeat Tracing (Freeze Protection) BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEICathodic Protection BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIPlant Electrical and Mechanical Tie-In BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIA Absorber TowerFlow Models By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersAbsorber Material By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersSide-Mounted Agitators BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIMist Eliminators Blades By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMist Eliminators Support Structure By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMist Eliminator Wash Headers internal By Others By Others By Others By Others By Others By Others By Others By Others By Others By Others2 of 4Rev 0AREAITEM DESCRIPTIONBasicEngrgDetailDesignProcure Fab DeliverErectConsultErectionCommissionTest TrainingLG&E Service CompanyContract No. 501654Mill Creek FGD Performance Upgrade StudyCase 2 : Units 1, 2 & 3:4Mist Eliminator Wash Headers externalBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMist Eliminator Wash Headers internal SupportBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersAbsorber Internals BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIInspection Access Doors By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersGas Sample Test Ports By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersInstrumentation By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersAccess Steel (including handrails, platforms, stairs, flooring, gratingeBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersStructural Steel By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersFoundations By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersElectrical Hoists By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersElectrical Power Supply By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMotor Starters and Control Centers By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMotors low Voltage By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersRaceway, Conduit, Pullboxes, Wiring, Cabling (excludes skid equipmBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersPlant Electrical and Mechanical Tie-In By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersProject / Construction AdministrationEnviromental Licensing and Permits By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersBuilding Licensing and Permits By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersLimestone Licensing and Permits By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersProject Master Schedule BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIProject Schedule- Design,Procure,Fabricate&Deliver BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIConstruction Safety Program BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIProject Labor Plan BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIQA/QC Program BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIStart-up Field Service, Equipment Commisioning & Turnover BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIPersonnel Training BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIO & M Manuals BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIOptimization & Acceptance Testing BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIEquipment Storage BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIEquipment Precommision Maintenance BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIConstruction Facilities - Temporary BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI3 of 4Rev 0AREAITEM DESCRIPTIONBasicEngrgDetailDesignProcure Fab DeliverErectConsultErectionCommissionTest TrainingLG&E Service CompanyContract No. 501654Mill Creek FGD Performance Upgrade StudyCase 2 : Units 1, 2 & 3:4Construction Facilities - PermanentBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersSite Clean-upBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIAsbestos Testing & RemovalBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersLead Paint Testing & RemovalBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersFinish Painting and Field Touch-upBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI4 of 4Rev 0AREAITEM DESCRIPTIONBasicEngrgDetailDesignProcure Fab DeliverErectConsultErectionCommissionTest TrainingC Gas PathInlet Ductwork By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersOutlet Ductwork By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersFlow Models By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersExpansion Joints BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIDuctwork Internals (flow screen, hoist beam) By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersNew ID & Booster FansBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersNew ID & Booster Fan MotorsBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersInspection Access DoorsBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersGas Sample Test PortsBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersInsulation & Lagging For All ComponentsBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersInstrumentationBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersActuated Valves/DampersBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersManuel Valves/DampersBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersAccess Steel (including handrails, platforms, stairs, flooring, gratingeBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersStructural Steel By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersFoundations By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersElectrical Power Supply By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMotor Starters and Control Centers By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMotors low Voltage By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersPipes > 2 in incl Support By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersPipes < 2 in incl Support By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersRaceway, Conduit, Pullboxes, Wiring, Cabling (excludes skid equipmBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersHeat Tracing (Freeze Protection) By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersCathodic Protection By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersPlant Electrical and Mechanical Tie-In By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersA Oxidation Air SystemOxidation Air Compressor By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersOxidation Air Agitators BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIOxidation Air Pressure Relief Valves BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIExternal Headers BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEILG&E Service CompanyContract No. 501654Mill Creek FGD Performance Upgrade StudyCase 3 : Units 1, 2 & 3:41 of 4Rev 0AREAITEM DESCRIPTIONBasicEngrgDetailDesignProcure Fab DeliverErectConsultErectionCommissionTest TrainingLG&E Service CompanyContract No. 501654Mill Creek FGD Performance Upgrade StudyCase 3 : Units 1, 2 & 3:4Internal LancesBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEISpray NozzlesBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIInlet SilencerBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersInlet FilterBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersInstrumentationBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersControl ValvesBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersActuated ValvesBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersManuel ValvesBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersPLC ControlsBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersAccess Steel (including handrails, platforms, stairs, flooring, gratingeBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersStructural Steel By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersFoundations By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersElectrical Hoists By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersElectrical Power Supply By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMotor Starters and Control Centers By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMotors low Voltage By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMotors medium Voltage By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersPipes > 2 in incl Support BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIPipes < 2 in incl Support BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIRaceway, Conduit, Pullboxes, Wiring, Cabling (excludes skid equipmBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersRaceway, Conduit, Pullboxes, Wiring, Cabling on Skids By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersHeat Tracing (Freeze Protection) By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersCathodic Protection By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersPlant Electrical and Mechanical Tie-In By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersA Absorber Recycle Pumps SystemAbsorber Recycle Pumps incl Gear Box - Unit 3 Gear Boxes only BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIOil Circulation and CoolersBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIAbsorber Recycle Pipes ExternalBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIAbsorber Recycle Pipes InternalBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIexpansion JointsBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEISpray NozzlesBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIInstrumentationBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI2 of 4Rev 0AREAITEM DESCRIPTIONBasicEngrgDetailDesignProcure Fab DeliverErectConsultErectionCommissionTest TrainingLG&E Service CompanyContract No. 501654Mill Creek FGD Performance Upgrade StudyCase 3 : Units 1, 2 & 3:4Actuated ValvesBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersManuel ValvesBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersPLC ControlsBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIAccess Steel (including handrails, platforms, stairs, flooring, gratingeBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersStructural Steel By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersFoundations BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIElectrical Hoists By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersElectrical Power Supply BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIMotor Starters and Control Centers BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIMotors low Voltage BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIMotors medium Voltage BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIPipes > 2 in incl Support BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIPipes < 2 in incl Support BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIRaceway, Conduit, Pullboxes, Wiring, Cabling (excludes skid equipmBPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIRaceway, Conduit, Pullboxes, Wiring, Cabling on Skids BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIHeat Tracing (Freeze Protection) BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEICathodic Protection BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIPlant Electrical and Mechanical Tie-In BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIA Absorber TowerFlow Models BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIAbsorber Material BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEISide-Mounted Agitators BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIMist Eliminators Blades BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIMist Eliminators Support Structure BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIMist Eliminator Wash Headers internal BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIMist Eliminator Wash Headers external BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIMist Eliminator Wash Headers internal Support BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIAbsorber Internals BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIInspection Access Doors By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersGas Sample Test Ports By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersInstrumentation BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIAccess Steel (including handrails, platforms, stairs, flooring, gratingeBy Others By Others By Others By Others By Others By Others By Others By Others By Others By Others3 of 4Rev 0AREAITEM DESCRIPTIONBasicEngrgDetailDesignProcure Fab DeliverErectConsultErectionCommissionTest TrainingLG&E Service CompanyContract No. 501654Mill Creek FGD Performance Upgrade StudyCase 3 : Units 1, 2 & 3:4Structural SteelBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersFoundationsBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersElectrical HoistsBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersElectrical Power SupplyBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMotor Starters and Control CentersBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersMotors low VoltageBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersRaceway, Conduit, Pullboxes, Wiring, Cabling (excludes skid equipmBy Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersPlant Electrical and Mechanical Tie-In By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersProject / Construction AdministrationEnviromental Licensing and Permits By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersBuilding Licensing and Permits By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersLimestone Licensing and Permits By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersProject Master Schedule BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIProject Schedule- Design,Procure,Fabricate&Deliver BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIConstruction Safety Program BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIProject Labor Plan BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIQA/QC Program BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIStart-up Field Service, Equipment Commisioning & Turnover BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIPersonnel Training BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIO & M Manuals BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIOptimization & Acceptance Testing BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIEquipment Storage BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIEquipment Precommision Maintenance BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIConstruction Facilities - Temporary BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIConstruction Facilities - Permanent By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersSite Clean-up BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEIAsbestos Testing & Removal By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersLead Paint Testing & Removal By Others By Others By Others By Others By Others By Others By Others By Others By Others By OthersFinish Painting and Field Touch-up BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI BPEI4 of 4Activity NameContractNumberOrigDurLG&E Mill Creek Units 1-4 WFGD Upgrade Study7710No Mill Creek Unit #0Engineering0Case - 2714Unit #1337Engineering80Procurement93Fabrication & Delivery253Construction80Outage19Startup & Commissioning20Unit #2337Engineering80Procurement93Fabrication & Delivery253Construction80Outage19Startup & Commissioning20Unit #3274Engineering80Procurement80Fabrication & Delivery200Construction21Outage23Startup & Commissioning20Case - 3771Unit #1391Engineering80Procurement93Fabrication & Delivery2583456789111111111122222222223333333333444MonthLG&E Mill Creek Units 1-4 WFGD Upgrade StudyNo Mill Creek Unit #EngineeringCase - 2Unit #1EngineeringProcurementFabrication & DeliveryConstructionOutageStartup & CommissioningUnit #2EngineeringProcurementFabrication & DeliveryConstructionOutageStartup & CommissioningUnit #3EngineeringProcurementFabrication & DeliveryConstructionOutageStartup & CommissioningCase - 3Unit #1EngineeringProcurementFabrication & DeliveryRemaining WorkCritical Remaining WorkMilestoneSummaryBabcock Power Environmental IncMill Creek FGD EPC SummaryPage 1 of 2Activity NameContractNumberOrigDurConstruction105Outage31Startup & Commissioning20Unit #2412Engineering80Procurement93Fabrication & Delivery258Construction100Outage32Startup & Commissioning20Unit #3331Engineering80Procurement80Fabrication & Delivery210Construction35Outage31Startup & Commissioning203456789111111111122222222223333333333444MonthConstructionOutageStartup & CommissioningUnit #2EngineeringProcurementFabrication & DeliveryConstructionOutageStartup & CommissioningUnit #3EngineeringProcurementFabrication & DeliveryConstructionOutageStartup & CommissioningActivity NameOrigDur0No Mill Creek Unit #0Engineering0Babcock Power Receive Notice to Proceed0Case - 2714Unit #1337Engineering80Design Calculations20Conduct CFD Modeling40Conduct Physical Modeling60Develop Equipment D&R Sheets10Develop Mechanical Drawings60Procurement93Issue P.O. Recycle Pumps10Issue P.O. Agitators10Issue P.O. Spray Nozzles10Issue P.O. Recycle Piping10Issue P.O. Wall Rings10Issue P.O. Modified Oxidation Air Lances10Issue P.O. Spray Piping Hangers & Hardware10Issue P.O. Air Piping, Hangers & Hardware10Fabrication & Delivery253Fabricate Recycle Pumps210Fabricate Agitators180Fabricate Spray Nozzles130Fabricate Wall Rings150Fabricate Recycle Piping180Fabricate Spray Piping Hangers & Hardware120Fabricate Modified Oxidation Air Lances140Fabricate Air Piping, Hangers & Hardware100Deliver Spray Nozzles101234567891111111111222222222233333333334MonthNo Mill Creek Unit #EngineeringBabcock Power Receive Notice to ProceedCase - 2Unit #1EngineeringProcurementFabrication & DeliveryRemaining WorkCritical Remaining WorkMilestoneSummaryBabcock Power Environmental IncMill Creek FGD EPC DetailedPage 1 of 11Activity NameOrigDurDeliver Agitators10Deliver Air Piping, Hangers and Hardware10Deliver Spray Piping Hangers and Hardware10Deliver Recycle Pumps20Deliver Wall Rings10Deliver Modified Oxidation Air Lances10Deliver Recycle Piping10Construction80Mobilze Construction10Excavate Recycle Pump Foundations30Form & Pour Recycle Pump Foundations30Run New Electrical Cables to Recycle Pumps20Unload Outage Materials5Set Up Scaffolding for Outage10Inventory and Store Outage Material10Set Up Recycle Line Rigging10Outage19Commence Outage1Remove Electrical Recycle Pump & Motor5Remove Misc. Electrical Interferences & Instrumentation5Demo Recycle Pump and Motors6Demo Recycle Outlet Lines to Spray Headers5Set Recycle Pumps5Install Wall Rings5Remove Recycle Spray Nozzles4Install Recycle Piping10Install Agitators7Align Recycle Pumps10Install Oxidation Air Nozzles10Reinstall Electrical Removed for Access.3Reinstall Instrumentation Removed for Access.3Outage Complete1Startup & Commissioning20Start Up and Commissioning20Unit #2337Engineering80Design Calculations201234567891111111111222222222233333333334MonthConstructionOutageStartup & CommissioningUnit #2EngineeringActivity NameOrigDurConduct CFD Modeling40Conduct Physical Modeling60Develop Equipment D&R Sheets10Develop Mechanical Drawings60Procurement93Issue P.O. Recycle Pumps10Issue P.O. Agitators10Issue P.O. Spray Nozzles10Issue P.O. Recycle Piping10Issue P.O. Wall Rings10Issue P.O. Modified Oxidation Air Lances10Issue P.O. Spray Piping Hangers & Hardware10Issue P.O. Air Piping, Hangers & Hardware10Fabrication & Delivery253Fabricate Recycle Pumps210Fabricate Agitators180Fabricate Spray Nozzles130Fabricate Wall Rings150Fabricate Recycle Piping180Fabricate Spray Piping Hangers & Hardware120Fabricate Modified Oxidation Air Lances140Fabricate Air Piping, Hangers & Hardware100Deliver Spray Nozzles10Deliver Agitators10Deliver Air Piping, Hangers and Hardware10Deliver Spray Piping Hangers and Hardware10Deliver Recycle Pumps20Deliver Wall Rings10Deliver Modified Oxidation Air Lances10Deliver Recycle Piping10Construction80Mobilze Construction10Excavate Recycle Pump Foundations30Form & Pour Recycle Pump Foundations30Run New Electrical Cables to Recycle Pumps20Unload Outage Materials5Set Up Scaffolding for Outage10Inventory and Store Outage Material101234567891111111111222222222233333333334MonthProcurementFabrication & DeliveryConstructionActivity NameOrigDurSet Up Recycle Line Rigging10Outage19Commence Outage1Remove Electrical Recycle Pump & Motor5Remove Misc. Electrical Interferences & Instrumentation5Demo Recycle Pump and Motors6Demo Recycle Outlet Lines to Spray Headers5Set Recycle Pumps5Install Wall Rings5Remove Recycle Spray Nozzles4Install Recycle Piping10Install Agitators7Align Recycle Pumps10Install Oxidation Air Nozzles10Reinstall Electrical Removed for Access.3Reinstall Instrumentation Removed for Access.3Outage Complete1Startup & Commissioning20Start Up and Commissioning20Unit #3274Engineering80Design Calculations20Conduct CFD Modeling40Conduct Physical Modeling60Develop Equipment D&R Sheets10Develop Mechanical Drawings60Procurement80Issue P.O. Agitators10Issue P.O. Wall Rings10Issue P.O. Modified Oxidation Air Lances10Issue P.O. Spray Nozzles10Issue P.O. Spray Piping Hangers & Hardware10Issue P.O. Air Piping, Hangers & Hardware10Fabrication & Delivery200Fabricate Agitators180Fabricate Wall Rings150Fabricate Modified Oxidation Air Lances1401234567891111111111222222222233333333334MonthOutageStartup & CommissioningUnit #3EngineeringProcurementFabrication & DeliveryActivity NameOrigDurFabricate Spray Piping Hangers & Hardware120Fabricate Spray Nozzles130Fabricate Air Piping, Hangers & Hardware100Deliver Air Piping, Hangers and Hardware10Deliver Agitators10Deliver Spray Piping Hangers and Hardware10Deliver Wall Rings10Deliver Spray Nozzles10Construction21Mobilze Construction10Remove Electrical and I&C Interferences15Unload Outage Materials5Inventory and Store Outage Material10Outage23Commence Outage1Install Wall Rings5Remove Recycle Spray Nozzles15Set New Recycle Pump Gear Boxes20Install Agitators7Install Oxidation Air Nozzles10Reinstall Electrical Removed for Access.10Reinstall Instrumentation Removed for Access.10Align Recycle Pump Gear Boxes5Outage Complete1Startup & Commissioning20Start Up and Commissioning20Case - 3771Unit #1391Engineering80Design Calculations20Conduct CFD Modeling40Conduct Physical Modeling60Develop Equipment D&R Sheets10Develop Mechanical Drawings60Procurement93Issue P.O. Recycle Pumps10Issue P.O. Agitators101234567891111111111222222222233333333334MonthConstructionOutageStartup & CommissioningCase - 3Unit #1EngineeringProcurementActivity NameOrigDurIssue P.O. Spray Nozzles10Issue P.O. Recycle Spray Headers10Issue P.O. Recycle Spray Bull Horns5Issue P.O. Mist Eliminator5Issue P.O. Absorber Shell10Issue P.O. Outlet Expansion Joint5Issue P.O. Recycle Piping10Issue P.O. Wall Rings10Issue P.O. Modified Oxidation Air Lances10Issue P.O. Spray Piping Hangers & Hardware10Issue P.O. Air Piping, Hangers & Hardware10Fabrication & Delivery258Fabricate Recycle Pumps210Fabricate Agitators180Fabricate Spray Nozzles130Fabricate Recycle Spray Headers200Fabricate Mist Eliminator160Fabricate Recycle Spray Bull Horns180Fabricate Absorber Shell190Fabricate Outlet Expansion Joint160Fabricate Wall Rings150Fabricate Recycle Piping180Fabricate Spray Piping Hangers & Hardware120Fabricate Modified Oxidation Air Lances140Fabricate Air Piping, Hangers & Hardware100Deliver Spray Nozzles10Deliver Agitators10Deliver Air Piping, Hangers and Hardware10Deliver Spray Piping Hangers and Hardware10Deliver Recycle Pumps20Deliver Mist Eliminator10Deliver Wall Rings10Deliver Modified Oxidation Air Lances10Deliver Outlet Expansion Joint10Deliver Recycle Spray Bull Horns10Deliver Recycle Spray Headers10Deliver Absorber Shell20Deliver Recycle Piping101234567891111111111222222222233333333334MonthFabrication & DeliveryActivity NameOrigDurConstruction105Mobilze Construction10Excavate Recycle Pump Foundations30Run New Electrical Cables to Recycle Pumps20Form & Pour Recycle Pump Foundations30Set Up Scaffolding for Outage10Set Up Recycle Line Rigging10Unload Outage Materials5Inventory and Store Outage Material10Ground Fab Absorber Assembly40Outage31Commence Outage1Remove Electrical Recycle Pump & Motor5Remove Misc. Electrical Interferences & Instrumentation5Demo Existing Absorber5Demo Recycle Pump and Motors6Demo Recycle Outlet Lines to Spray Headers5Set Recycle Pumps5Install Wall Rings5Remove Recycle Spray Nozzles4Install Recycle Piping10Raise & Rig Absorber Section2Install Agitators7Align Recycle Pumps10Weld Absorber Section7Install Oxidation Air Nozzles8Reinstall Electrical Removed for Access.3Reinstall Instrumentation Removed for Access.3Install New Outlet Expansion Joint3Connect Exist. Outlet Ductwork to New Absorber4Install Insulatation and Lagging to Absorber8Outage Complete1Startup & Commissioning20Start Up and Commissioning20Unit #2412Engineering80Design Calculations201234567891111111111222222222233333333334MonthConstructionMobilze ConstructionOutageStartup & CommissioningUnit #2EngineeringActivity NameOrigDurConduct CFD Modeling40Conduct Physical Modeling60Develop Equipment D&R Sheets10Develop Mechanical Drawings60Procurement93Issue P.O. Recycle Pumps10Issue P.O. Agitators10Issue P.O. Spray Nozzles10Issue P.O. Recycle Spray Headers10Issue P.O. Absorber Shell10Issue P.O. Recycle Spray Bull Horns5Issue P.O. Mist Eliminator5Issue P.O. Outlet Expansion Joint5Issue P.O. Recycle Piping10Issue P.O. Wall Rings10Issue P.O. Modified Oxidation Air Lances10Issue P.O. Spray Piping Hangers & Hardware10Issue P.O. Air Piping, Hangers & Hardware10Fabrication & Delivery258Fabricate Recycle Pumps210Fabricate Agitators180Fabricate Spray Nozzles130Fabricate Recycle Spray Headers200Fabricate Mist Eliminator160Fabricate Recycle Spray Bull Horns180Fabricate Absorber Shell190Fabricate Outlet Expansion Joint160Fabricate Wall Rings150Fabricate Recycle Piping180Fabricate Spray Piping Hangers & Hardware120Fabricate Modified Oxidation Air Lances140Fabricate Air Piping, Hangers & Hardware100Deliver Spray Nozzles10Deliver Agitators10Deliver Air Piping, Hangers and Hardware10Deliver Spray Piping Hangers and Hardware10Deliver Recycle Pumps20Deliver Modified Oxidation Air Lances101234567891111111111222222222233333333334MonthProcurementFabrication & DeliveryActivity NameOrigDurDeliver Mist Eliminator10Deliver Outlet Expansion Joint5Deliver Recycle Spray Bull Horns10Deliver Absorber Shell10Deliver Recycle Piping10Deliver Recycle Spray Headers10Construction100Mobilze Construction10Excavate Recycle Pump Foundations30Run New Electrical Cables to Recycle Pumps20Form & Pour Recycle Pump Foundations30Set Up Scaffolding for Outage10Set Up Recycle Line Rigging10Unload Outage Materials5Inventory and Store Outage Material10Ground Fab Absorber Assembly40Outage32Commence Outage1Remove Electrical Recycle Pump & Motor5Remove Misc. Electrical Interferences & Instrumentation5Demo Existing Absorber5Demo Recycle Pump and Motors6Demo Recycle Outlet Lines to Spray Headers5Install Wall Rings5Set Recycle Pumps5Remove Recycle Spray Nozzles4Install Recycle Piping10Raise & Rig Absorber Section2Install Agitators7Align Recycle Pumps10Weld Absorber Section7Install Oxidation Air Nozzles8Reinstall Electrical Removed for Access.3Reinstall Instrumentation Removed for Access.3Install New Outlet Expansion Joint3Connect Exist. Outlet Ductwork to New Absorber4Install Insulatation and Lagging to Absorber8Outage Complete11234567891111111111222222222233333333334MonthConstructionMobilze ConstructionOutageActivity NameOrigDurStartup & Commissioning20Start Up and Commissioning20Unit #3331Engineering80Design Calculations20Conduct CFD Modeling40Conduct Physical Modeling60Develop Equipment D&R Sheets10Develop Mechanical Drawings60Procurement80Issue P.O. Agitators10Issue P.O. Wall Rings10Issue P.O. Spray Nozzles10Issue P.O. Spray Piping Hangers & Hardware10Issue P.O. Modified Oxidation Air Lances10Issue P.O. Air Piping, Hangers & Hardware10Fabrication & Delivery210Fabricate Agitators180Fabricate Wall Rings150Fabricate Spray Piping Hangers & Hardware120Fabricate Spray Nozzles130Fabricate Modified Oxidation Air Lances140Fabricate Air Piping, Hangers & Hardware100Deliver Air Piping, Hangers and Hardware10Deliver Agitators10Deliver Spray Piping Hangers and Hardware10Deliver Spray Nozzles10Deliver Wall Rings10Construction35Mobilze Construction10Unload Outage Materials5Remove Electrical and I&C Interferences15Inventory and Store Outage Material10Ground Fab Absorber Assembly20Outage31Commence Outage1Remove Electrical Recycle Pump & Motor51234567891111111111222222222233333333334MonthStartup & CommissioningUnit #3EngineeringProcurementFabrication & DeliveryConstructionMobilze ConstructionOutageCommence OutageRemove Electrical Recycle Pump & MotorActivity NameOrigDurRemove Misc. Electrical Interferences & Instrumentation5Demo Existing Absorber5Raise & Rig Absorber Section2Remove Recycle Spray Nozzles4Install Wall Rings5Weld Absorber Section7Install Agitators7Install Oxidation Air Nozzles8Install New Outlet Expansion Joint3Reinstall Electrical Removed for Access.3Reinstall Instrumentation Removed for Access.3Connect Exist. Outlet Ductwork to New Absorber4Install Insulatation and Lagging to Absorber8Outage Complete1Startup & Commissioning20Start Up and Commissioning201234567891111111111222222222233333333334MonthRemove Misc. Electrical Interferences & InstrumentationDemo Existing AbsorberRaise & Rig Absorber SectionWeld Absorber SectionInstall New Outlet Expansion JointConnect Exist. Outlet Ductwork to New AbsorberInstall Insulatation and Lagging to AbsorberOutage CompleteStartup & CommissioningStart Up and Commissioning

### LG&E Services Company
Contract No. 501654
Mill Creek FGD Perfor mance Upgrade Study

Budget Engineering, Procurement and Construction Estimate February 15, 2011

Description Engineering Equipment Construction Total

Case 2: Unit 1 $1,922,629 $5,365,667 $3,253,216 $10,541,512

Case 2: Unit 2 $1,922,629 $5,365,667 $3,343,710 $10,632,006

Case 2: Unit 3 $1,922,629 $6,735,206 $5,378,000 $14,035,835

Case 3: Unit 1 $2,949,580 $10,573,006 $6,905,881 $20,428,467

Case 3: Unit 2 $2,949,580 $10,573,006 $7,044,859 $20,567,445

Case 3: Unit 3 $2,949,580 $17,504,859 $12,489,678 $32,944,117