Performance and Benefits of Flue Gas Treatment Using Thiosorbic Lime

1
Performance and Benefits of Flue Gas Treatment
Using Thiosorbic Lime

• Presented by
• Carmeuse North America

Carmeuse North America makes no warranty or
representation, expressed or implied, and assumes
no liability with respect to the use of, or
damages resulting from the use of, any
information, apparatus, method or process
disclosed in this document.
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BACKGROUND ON CARMEUSE
3
Carmeuse North America
- Background

• Part of the Carmeuse Group
• Joint Venture of
• 60 Carmeuse S.A. (Belgium)
• 40 Lafarge S. A. (France)
• Carmeuse
• 1 billion privately-held lime company founded in
  1860
• 60 plants in 14 countries
• Lafarge
• 11 billion publicly-held construction materials
  company founded in 1833
• Operations in 60 countries

4
Lime Plant Locations in U.S. and Canada
- Background
Carmeuse
While Carmeuse North America is the leading
supplier, FGD lime is widely available
North America
plant locations
5
Carmeuse Provides
- Background

• Thiosorbic Lime for flue gas desulfurization
  (FGD) in coal-fired plants
• Access to Thiosorbic process technology
• Carmeuse works in cooperation with major FGD
  equipment suppliers to provide the best system
  for the customers requirements
• Technical support for FGD users
• FGD start-up, operator training, and operations
  support
• Over 25 years experience in FGD in coal-fired
  power plants

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BENEFITS OF THETHIOSORBIC FGD PROCESS
- Thiosorbic Process
7
Benefits of Thiosorbic FGD process
- Thiosorbic Process

• Ultra-low SO2 emissions with high-sulfur fuel
• 99 SO2 removal with high-sulfur coal
• Lower FGD capital cost
• Lower FGD power consumption
• Valuable by-products wallboard-quality gypsum
  and magnesium hydroxide Mg(OH)2
• 25 year record of reliability
• 17,700 MW base of experience

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Thiosorbic Wet FGD Applications 16 Stations 34
Units 17,700 MW
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Thiosorbic FGD Process Description
- Thiosorbic Process

• Wet FGD process
• Uses lime reagent with 3-6 wt. MgO
• Mg increases SO2 removal and allows low L/G
• 45 L/G (gpm/1000 acfm) for 99 removal with
  high-sulfur fuel
• Low chemical scaling potential
• Liquid in absorber slurry only 10
  gypsum-saturated

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Thiosorbic FGD Process
- Thiosorbic Process
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FGD Process Comparison Thiosorbic vs. Limestone
Forced Oxidation (LSFO)
- Thiosorbic Process

• Higher SO2 removal
• Up to 99 vs. 95 for LSFO
• Lower Power Consumption
• 1.4 versus 2.0 for LSFO for high-sulfur coal
• Higher Reagent Utilization
• 99.9 vs. up to 97 for LSFO
• Better Gypsum Quality
• 98-99 pure, bright white vs. 95, brown or tan
  for limestone

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Comparison of Gypsum from Thiosorbic Lime with
LSFO Gypsum
- Thiosorbic Process
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FGD Process Comparison Thiosorbic vs. LSFO
- Thiosorbic Process

• Lower Capital Cost
• 8-12 lower capital cost
• Much smaller absorbers
• Fewer recycle pumps, fewer spray headers, smaller
  recirculation tank
• Lower maintenance cost
• Generate more valuable SO2 allowances

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FGD Process Comparison Absorber Size
- Thiosorbic Process
These absorbers were supplied by the same FGD
equipment supplier at two different sites. The
difference in height is due solely to FGD process
type. LSFO requires more absorber spray headers,
greater L/G, more recirculation pumps, and a
larger hold time in the recirculation tank,
leading to a substantially taller, more costly
absorber.
LSFO
125 ft 38.1 m
Thiosorbic
55 ft 16.8 m
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Thiosorbic Absorber at Zimmer Station

• Example of compact absorber
• Babcock Wilcox design
• Only 54 ft high (grade to top tangent line)
• One operating recycle pump, one spare
• Design L/G is 21 gal/1000 acfm (3 l/m3) for 91
  SO2 removal
• Achieved 96 SO2 removal in 1991 performance test
  on 3.5 sulfur coal

16
Thiosorbic Absorber At HMPL Station 2

• Example of compact absorber
• Wheelabrator design
• Only 46 ft high (grade to top tangent line)
• One operating recycle pump, one spare
• Design L/G is 30 gal/1000 acfm (4 l/m3) for 95
  SO2 removal
• Achieved 96 SO2 removal in 1994 performance test
  on 3 sulfur coal

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BENEFITS OF BYPRODUCT MAGNESIUM HYDROXIDE FROM
THE THIOSORBIC PROCESS
- Byproduct Mg(OH)2 from the Thiosorbic Process
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Thiosorbic FGD Processwith Byproduct Mg(OH)2
Production
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Benefits of Byproduct Magnesium Hydroxide
- Byproduct Mg(OH)2 from the Thiosorbic Process

• Thiosorbic process allows option for on-site
  production of magnesium hydroxide
• Demonstrated for furnace injection and SO3
  control in 800 MW and 1300 MW boilers
• Reduces furnace-generated SO3 emissions by 90
• Substantially reduces visible plume opacity

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Mg(OH)2 Injection for SO3 Control
- Byproduct Mg(OH)2 from the Thiosorbic Process
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Furnace SO3 Removal vs. MgSO3 Ratio in 1300 MW
Boiler
- Byproduct Mg(OH)2 from the Thiosorbic Process
100
90
80
70
60
50
Full-scale demonstration of SO3 control with
Thiosorbic byproduct Mg(OH)2
Full-scale demonstration of SO3 control with
Thiosorbic byproduct Mg(OH)2
40
30
20
10
0
0
1
2
3
4
5
6
7
8
MgSO3 Ratio
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Reduction in Visible Opacity withBy-product
Mg(OH)2 Treatment
- Byproduct Mg(OH)2 from the Thiosorbic Process
Untreated Treated
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Benefits of Byproduct Magnesium Hydroxide
- Byproduct Mg(OH)2 from the Thiosorbic Process

• Increases melting point of boiler slag
• Reduces strength of slag deposits increases
  friability and fracture for ease of removal
• Increases boiler efficiency
• Cleaner heat transfer surfaces
• Allows lower air heater outlet temperature

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Benefits of Byproduct Magnesium Hydroxide
- Byproduct Mg(OH)2 from the Thiosorbic Process

• Provides FGD wastewater treatment As, Cd, Pb,
  Ni, Hg below detection limits
• Reduces size and operating costs of wastewater
  treatment system no TSS removal and
  coagulation/lime precipitation steps required no
  BOD (DBA) removal
• Eliminates disposal of (RCRA-unexcluded)
  wastewater treatment sludge allows co-mangement
  via return to furnace and combination with flyash

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Full-scale Application of Byproduct Mg(OH)2
Injection for SO3 Control
- Byproduct Mg(OH)2 from the Thiosorbic Process

• A 1400 MW installation begins operation 1st
  quarter 2004

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Potential Cost Savings from Furnace Injection of
Magnesium Hydroxide
- Byproduct Mg(OH)2 from the Thiosorbic Process

• Increase in plant efficiency due to cleaner
  boiler tubes and low acid dew point 1 increase
  per 35 F lower air heater exit temperature
• Coal savings due to use of lower temperature ash
  fusion coal

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Factors Used to Determine Cost Benefits of Boiler
Injection of Byproduct Mg(OH)2
- Byproduct Mg(OH)2 from the Thiosorbic Process
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Lower Life Cycle Cost with Thiosorbic Process and
Byproduct Mg(OH)2 Compared with LSFO
- Byproduct Mg(OH)2 from the Thiosorbic Process
40
base case
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Increased availability furnace efficiency
Increased availability furnace efficiency,
reduced fuel cost
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Increasing cost
competitiveness of Thiosorbic process
Lower life cycle cost for Thiosorbic process in
area above each line
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Limestone cost, /ton
20
15
10
Based on 3 sulfur bituminous coal
5
0
40
45
50
55
60
65
70
Lime cost, /ton
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HYDRATED LIME INJECTIONFOR SO3 CONTROL
- Hydrated Lime for SO3 Control
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Ca(OH)2 Injection for SO3 Control
- Hydrated Lime for SO3 Control

• Hydrated lime Ca(OH)2 has been demonstrated at
  1300 MW for control of SO3 emissions after
  selective catalytic reduction (SCR)
• Hydrated lime powder can be injected into flue
  gas immediately after the air heater and before
  the particulate collector, or injected after the
  particulate collector and before the Thiosorbic
  FGD system

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Ca(OH)2 Injection for SO3 Control
- Hydrated Lime for SO3 Control
Ca(OH)2 Injection Locations
Selective Catalytic Reduction
Furnace
ESP
Thiosorbic FGD
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Ca(OH)2 Injection for SO3 Control
- Hydrated Lime for SO3 Control

• Hydrated lime injected before the particulate
  collector (e.g. ESP) is removed with fly ash
• Hydrated lime injected before the Thiosorbic FGD
  system is removed by impingement with absorber
  spays
• Results in complete utilization of the hydrated
  lime which substantially reduces reagent cost for
  SO3 control
• 90 removal of SCR-generated SO3 is possible at
  CaSO3 molar ratio of 8

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Performance and Benefits of Flue Gas Treatment
Using Thiosorbic LimeConclusions

• The Thiosorbic process is a widely utilized FGD
  process with a 25 record of successful operation
• The Thiosorbic lime FGD process provides better
  SO2 removal performance than the LSFO process
• The Thiosorbic process allows lower FGD capital
  cost, lower power consumption, and lower life
  cycle cost than the LSFO process
• Byproduct Mg(OH)2 provides efficient control of
  furnace SO3 emissions and additional operating
  benefits and cost savings
• Hydrated lime provides efficient, low-cost
  control of SO3 formed during SCR