Comprehensive Approach to
Reduce Emissions and
Increase Capacity and
Efficiency
© 2016 The Babcock & Wilcox Company. All rights reserved.
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Topic of Discussion
Case study describing a total plant approach to refurbishing
an existing electric utility generating asset
Generating Unit Specifications
729 MW gross
684 MW net
Operational 1981
Wyoming sub-bit “C” coal
CE (Alstom/GE) tangential-fired
boiler
© 2016 The Babcock & Wilcox Company. All rights reserved.
.2
Operating Issues/Problems
 Availability
• Pressure parts
 Capacity and heat rate
• Reheat steam temperature
• Turbine upgrade
 Emissions
• U.S. EPA mandates
© 2016 The Babcock & Wilcox Company. All rights reserved.
.3
Total Plant Approach
TURBINE
FUEL
MW
BOILER
EMISSIONS
AQCS
© 2016 The Babcock & Wilcox Company. All rights reserved.
.4
Boiler Pressure Part Upgrades
1. Front Lower Slope
Objective
• Reduce tube leaks and
forced outages
Approach
• Use furnace hopper
Energy Absorbing Tube
Support system to better
protect against falling
slag
© 2016 The Babcock & Wilcox Company. All rights reserved.
1
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Boiler Pressure Part Upgrades
1. Front Lower Slope
Objective
• Reduce tube leaks and
forced outages
Approach
• Use furnace hopper
Energy Absorbing Tube
Support system to better
protect against falling
slag
© 2016 The Babcock & Wilcox Company. All rights reserved.
.6
Boiler Pressure Part Upgrades
2. Superheater Division
Panels
Objective
• Maintain tube alignment without
over-restraining tubes (reduce
thermal stress)
2
Approach
• Use patented slip spacer alignment
castings, providing tube support
while allowing tube thermal
expansion
© 2016 The Babcock & Wilcox Company. All rights reserved.
.7
Boiler Pressure Part Upgrades
2. Superheater Division
Panels
Objective
• Maintain tube alignment without
over-restraining tubes (reduce
thermal stress)
Approach
• Use patented slip spacer alignment
castings, providing tube support
while allowing tube thermal
expansion
© 2016 The Babcock & Wilcox Company. All rights reserved.
.8
Boiler Pressure Part Upgrades
3. Economizer
Objective
• Reduce plugging potential
• Clear support stringers from sootblower lanes
• Design for potential future economizer
extension
3
Approach
• Apply increased side spacing (aligning
sections with superheater)
• Re-design the location, material, and
thickness of the support stringers
© 2016 The Babcock & Wilcox Company. All rights reserved.
.9
Boiler Pressure Part Upgrades
3. Economizer
Objective
• Reduce plugging potential
• Clear support stringers from sootblower lanes
• Design for potential future economizer
extension
Approach
• Apply increased side spacing (aligning
sections with superheater)
• Re-design the location, material, and
thickness of the support stringers
© 2016 The Babcock & Wilcox Company. All rights reserved.
.10
Availability
Unit availability improvement: 82% to 90%
TURBINE
FUEL
MW
BOILER
EMISSIONS
AQCS
© 2016 The Babcock & Wilcox Company. All rights reserved.
.11
Integrated Reheater Re-design
4. Reheater
Objective
4
• Achieve original design steam
temperature in tandem with turbine
upgrade (maximize cycle efficiency)
Approach
• Redesign reheater to optimize heating
surface in available space
© 2016 The Babcock & Wilcox Company. All rights reserved.
.12
Integrated Reheater Re-design
4. Reheater
Objective
• Achieve original design steam
temperature in tandem with turbine
upgrade (maximize cycle efficiency)
Approach
• Redesign reheater to optimize heating
surface in available space
© 2016 The Babcock & Wilcox Company. All rights reserved.
.13
Capacity and Heat Rate
Net Output: ~8% increase
Heat Rate: ~4.5% reduction
TURBINE
FUEL
MW
BOILER
EMISSIONS
AQCS
© 2016 The Babcock & Wilcox Company. All rights reserved.
.14
SO2 Emissions Control
Spray dryer absorber (SDA)
Mixes slurry with flue gas to
remove SO2, HCl, and HF
90-98% capture
© 2016 The Babcock & Wilcox Company. All rights reserved.
.15
Mercury Emissions Control
Activated carbon
injection (ACI)
Injects powdered
activated carbon
(PAC) to adsorb
mercury
90-96% capture
© 2016 The Babcock & Wilcox Company. All rights reserved.
.16
Particulate Emissions Control
Pulse jet fabric filter
(PJFF)
Removes SDA
byproducts and fly
ash
Up to 99.9% removal
© 2016 The Babcock & Wilcox Company. All rights reserved.
.17
Emissions
TURBINE
FUEL
MW
BOILER
Emissions (converted from
heat input basis):
 SO2 ≤ 96.5 mg/Nm3* (design fuel)
 Hg ≤ 0.96 µg/Nm3*
 PM (total) ≤ 18.1 mg/Nm3*
*dry flue gas at MCR
corrected to 6% O2
EMISSIONS
AQCS
© 2016 The Babcock & Wilcox Company. All rights reserved.
.18
Questions?
Questions?
The Babcock & Wilcox Company
email@babcock.com
+1 330-753-4511
DISCLAIMER
The Babcock & Wilcox Company (B&W) assumes no liability or responsibility with respect to the use of, or for damages resulting from the use of, any
information, methods, processes, or recommendations provided in this presentation. B&W expressly excludes and disclaims any and all warranties,
whether expressed or implied, which might arise or apply under law or equity or custom or usage of trade, including, without limitation, any
warranties of merchantability and/or fitness for a particular or intended purpose.
© 2016 The Babcock & Wilcox Company. All rights reserved.
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