CFB Boiler

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Modular CFB

• DESIGN FEATURES

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Modular CFB

• Standard Unit Sizes Offered
• Standard Arrangement and Detail Drawings Exist

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Modular CFB Boilers
Standard Unit Sizes

• 10 MW
• 15 MW
• 20 MW
• 30 MW
• 50 MW
• 70 MW

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Modular CFB Boilers
Unit Arrangements
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Modular CFB
Design Features

• Modular Design Concept
• Standard Components
• Bottom Support/Shop Fabrication Design
• Most Components are Shop Fabricated
• Truck-Shippable, Large Components
• Fast Construction Schedule
• Low Unit Profile - Under 95 Feet (29 meters) Tall

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Modular CFB BoilerOverview
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Modular CFB BoilerDuring Construction
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Modular CFB BoilerOverview
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Modular CFB BoilerOverview
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Modular CFB Boilers
Furnace Segment
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Furnace Interior - 20MWe
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Furnace Interior - 70 MWe
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Air Distributor/Tuyure Comparison
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Directional Flow Tuyeres (Cross Section)
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Directional Flow TuyeresBed Solids Flow Pattern
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Bed Level Control for Load Following
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Evaporative Tube Bundle(Natural Circulation)

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Overbed Feed
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Overbed Air-Swept Feeder
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Backpass Arrangement
Hanger Tubes
Flue Gas from Cyclone
Superheater
Steam Cooled Wall Tubes
Reheater (where applicable)
Economizer
Fly Ash Hopper
ALSTOM Power - Leadership in CFB Technology
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Modular CFB

• PROCESS FEATURES

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Modular CFB
Process Features

• Low Velocity Fluidization for Long Residence Time
• High Efficiency Cyclones to Circulate Fine
  Particles
• Highest Boiler Efficiency, Lowest Limestone
  Consumption
• Natural Circulation, In-Bed Evaporator Tubes
  Screens
• Continuous Purging of Oversized Bed Material
• Bed Level Control and Storage for Load Following
• Furnace Temperature Control Over Wide Load Range
• Lowest Emissions

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Schematic of Typical Modular CFB Boiler System
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Modular CFB

• PERFORMANCE

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Modular CFB
Process Advantages

• Small Cyclone Diameter Design Results in
• Higher Cyclone Fractional Efficiency / Lower Cut
  Point than Large Diameter Cyclones
• Highest Limestone Utilization
• Highest Carbon Conversion Efficiency
• Significant Overall Economic Advantages for
  Situations
• High Cost Sorbent Costs
• High Sulfur Fuels
• High Cost Fuels

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Cyclone Arrangement
To Backpass
Second Pass
Inlet Duct
Vortex Finder
Gunnite Refractory
To Lower Furnace
056 329p
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Modular CFB Boilers
Emissions from Operating Plants
1. SNCR used for NOx control 2. Limestone
addition used for SO2 control
Low Sulfur Emissions at Lowest Limestone Usage
(Ca/S)
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Assured Reliability
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Modular CFB
Performance

• Highest CFB Boiler Efficiency
• Sulfur Capture in Excess of 99 Is Being Achieved
  in Commercial Operation
• SO2 and NOx Levels in the 10 to 15 PPM (3 O2)
  Range
• Ca/S Ratio of 1.6 to 1.8 Can Be Guaranteed for 90
  to 95 Sulfur Capture