Wet Scrubber O&M Lessons Learned by B&W

Worldwide PollutionControl Association

IL Regional Technical SeminarIL Regional Technical SeminarAugust 3-4, 2010

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Wet FGD Lessons Learned - DesignWet FGD Lessons Learned - Designby

Greg Bielawski

WPCA Regional SeminarSpringfield IllinoisSpringfield, Illinois

August 4, 2010

Yesterday: Multiple Absorbers per Boiler:este day u t p e bso be s pe o eMany dampers & many more pumps

Proprietary and Confidential .2

Today: Single Absorber per BoilerToday: Single Absorber per Boiler

Proprietary and Confidential .3

Importance of Gas Flow Distribution

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Packed Towers No Longer Used

Excellent contactor, but big plugage problems

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B&W Absorber Gas Inlet with Tray

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Spiral Nozzle:Excellent Drop Size, but Not Suitablep ,

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Hollow Cone Spray Nozzle

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FRP Spray Headers

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FRP Can be done right, but there must be a stringent spec….

Alloy Spray Headers

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Rubber lining blockage:Common problem with Rubber-Lined Pipe p p

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Mist Eliminator Upgrade

Original Mist Eliminator Design New Modern Mist Eliminator Design

Mist Eliminator Upgrade

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Typical Lower & Upper Mist Eliminator

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Source: Munters

Mist Eliminator Wash System

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ME Wash StrainerME Wash Strainer

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Top of Mist Eliminator with Wash Header

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Wet FGD Absorber FireWet FGD Absorber Fire

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Absorber Pump with FRP Pipe (Note Supports)

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Absorber Pump Gearbox Failures:Gearboxes likely need water coolingGearboxes likely need water cooling

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Absorber Mixer Design

Mixers must be distributed around the tank, not clustered

installation angle = f (d1, d2, n2, q, quantity of agitators)

ß = too largeß = 0deposits at g

deposits inthe centre

pthe vesselwall

ß = optimalno deposits

S

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Source: Ekato

Mixer on Absorber Shell: Outboard Support Neededpp

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Source: Alstom Unit at Centralia

Agitator Motor DriveAgitator Motor Drive

Coleson Cove 7/8/04

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Erosion of Alloy Mixer Blade(Two Year Outage Inspection)(Two-Year Outage Inspection)

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Absorber Tank Access DoorNeed Big Doors; Must be to Codeg ;

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Source: Alstom Unit at Centralia

Thank You!Thank You!

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© 25© 2009 The Babcock & Wilcox

WFGD Operations & MaintenanceWFGD Operations & Maintenanceby

Greg Bielawski

WPCA Regional SeminarSpringfield IllinoisSpringfield, Illinois

August 4, 2010

Estimated Plant WFGD Operations per ShiftEstimated Plant WFGD Operations per Shift

Operator shift super 1x (shared)Operator shift super 1x (shared)

Control room operator 1x

Field operatorsField operatorsAQCS 2xElectrical 1x (shared)

Lab tech 1 per shift (for 2 shifts – shared)

Maintenance shared with boiler

Total Dedicated Personnel: 3Total Shared Personnel: 3+

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T i l Ab b M i t A ti itiTypical Absorber Maintenance Activities

Activity Description Frequency

Estimated Labor

ManhoursEquipment

On/OffAQCS On/Off

ABSORBERABSORBER

Inspect alloy parts 1 per year 24 off off

Inspect/repair internal piping 1 per year 24 off off

Inspect/clean nozzles 1 per year 24 off off

Inspect/clean mist eliminators 1 per year 24 off off

Inspect/clean flow distributors 1 per year 24 off off

Inspect/replace man way gaskets 1 per year 24 off off

Inspect fasteners 1 per year 24 off offInspect fasteners 1 per year 24 off off

List continues for many pages:

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Contact gtbielawski@babcock.com for complete set

E ti t d M i t C tEstimated Maintenance Costs for the Wet FGD System

Estimated annual maintenance manhours for the Wet FGD: ~6,900 hours

Estimated annual spare parts/materials cost for the Wet FGD: ~$515,000

Notes:

The above maintenance activities, frequency, and estimated labor , q y,values are typical and may vary dependent on equipment suppliers.

Total maintenance costs may vary in the industry from plant to plant.

Proprietary and Confidential © 2008 Babcock & Wilcox Power Generation Group, Inc. All rights reserved. .29

Thank You!Thank You!

Proprietary and Confidential .30© 2009 The Babcock & Wilcox Company. All rights reserved.