Second International Conference on Industrial Gas Turbine Technologies

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Second International Conference on Industrial Gas
Turbine Technologies 29-30th April 2004 Hotel
Golf, Bled Slovenia
Development of Coal Gasified Fueled Gas Turbine
Combustor for IGCC
Mikio Sato Central Research Institute of
Electric Power Industries
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Contents

• 1. IGCC demonstration plant project in Japan
• 2. Characteristics of gasified coal fuels
• 3. Development of Air-blown entrained-flow
  gasified low-Btu fueled 1500 deg-C-class
  combustor
• Subjects
• Design concept of combustor for IGCC
• Performance evaluated by combustion
  test
• 4. Conclusion

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Design ofIGCC Demonstration Plant
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Air-blown Entrained Flow Gasifier

• Air-Blown - Lower auxiliary power
  consumption than oxygen-blown
• Two Stage - Best balance of syngas calorie
  for GT combustion and high temperature for
  melting ash
• - Effective gas/slag quenching at the 2nd
  stage with coal gasification endothermic
  reaction
• Dry-Coal-Fed - Higher thermally efficient than
  Slurry-Coal-fed

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Schematic Diagram of IGCC
Gas Cleanup (cold)
Air-blown Gasifier
Gasifier
Syngas
Dry
Gypsum
Porous
Recovery
Coal
Filter
Feed
Combustor
ASU
N
S/T
G/T
Char
2
HRSG
O
2
Air
Air Compressor
M
Combined Cycle System
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Conceptual Drawing of IGCC Demonstration Plant
Gasifier
Gas Cleanup
Turbine Train
Air Separation Unit
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Schedule of IGCCDemonstration Plant Project
Fiscal year
2001
2002
2004
2003
2005
2006
2007
2008
2009
Demonstration Plant Tests
Design of plant
Construction of plant
Operation tests
Environmental Impact Assessment
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Features of air-blowngasified coal fuel

• Fuel calorific value(HHV) is around 1,000Kcal/m3,
  it is one tenth of that of LNG
• Theoretical maximum flame temp. is around 1,750
  deg-C, it is 400 deg-C lower than 2150 deg-C of
  LNG
• Main combustible component is carbon
• monoxide(CO)
• Fuel contains ammonia(NH3) around 1,000ppm in
  case of hot/dry synthetic gas cleanup
• Fuel contains char and heavy metals

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Typical compositions of air-blown and
oxygen-blownentrained-flow gasified coal fuel
Others
Air-blown gasified low-Btu fuel
Oxygen-blown gasified

medium-Btu fuel
N
N
N)
N)
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Flame temperature of gasified fuels
CH4
HHV
Theoretical adiabatic flame temperature
deg-C
Equivalence ratio
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Subjects of combustor development for Air-blown
IGCC Features Subjects
Calorific value is low Main comb. comp. is CO
Combustion Stability
Cooling air decreases associated with higher
combustion temp.
High-Efficient Cooling
Fuel contains NH3 of 1,000ppm
Low Fuel NOx Comb. Tech.
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Air distribution design of a gas turbine which
burns low-Btu coal gasified fuel
Dilution Air
Cooling Air
Supplied air split
Combustion Air (f0.83)
Combustor exit gas temp. C
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Development of Air-blown Gasified
Low-Btu Fueled 1500 C-class Gas Turbine
Combustor
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Design concept of combustor

• Combustion Stability
• ? Adoption of auxiliary combustor

• Low Fuel-NOx Combustion Technology
• ? Two stage combustion

• High-Efficient Cooling
• ? Deletion of primary- and dilution-air
• ? Combined cooling technique of Impingement
• cooling with film cooling
• ? Cooling air for transition piece is recycled
  for
• liner wall cooling

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NOx formation from NH3 contained in fuel
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Design concept of a 1500 C-class gas turbine
combustor
Reduction of Fuel-NOx
Combustion stability
fp 1.6
High-Efficiency Cooling
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1500 deg-C-class combustor
Secondary air holes
Auxiliary combustor
Main burner
Air
Fuel
Tested burner Combustion
liner
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Outline of Secondary air inlet section
Outer wall
Iner wall
Secondary air
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Secondary air holes
Primary combustion
Secondary combustion
Fig. Relation between the reaction time and the
equivalence ratio distribution, using
in the numerical analysis
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Fig. Relation between primary equivalence ratio
and conversion rate of NH3 in the fuel
to NOx
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Schematic diagram of research facility
.
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Research facility
Reformer
Flare Stack
Combustor test section
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Combustion testing rig
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• Test results
• (Thermal Characteristics of Liner Wall)

Exhaust temp. 1500 C HHV 1000kcal/m3 Press.
1.4MPa
heat resistant temp.
Liner wall temperature deg-C
Auxiliary combustor
Transition piece
Liner
Axial distance from burner mm
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• Test results
• (Effect of calorific value of fuel)

Exhaust temp. 1500 C Press. 0.1MPa
heat resistant temp.
HHV
Liner wall temperature deg-C
Axial distance from burner mm
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• Test results
• (Thermal NOx emission characteristics)

HHV 1,000kcal/m3 Press. 0.1MPa
Thermal NOx lt 6ppm
Thermal NOx Emission ppm (corrected at 16 O2)
Thermal NOx Emission ppm (corrected at 16 O2)
Exhaust temp. 1,500 C HHV 1,000kcal/m3
Combustor Exit Temp. deg-C
Press. inside Combustor MPa
Effect of combustor exit
Effect of pressure gas temp.
inside combustor

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• Test results
• (Total NOx emission Combustion efficiency)

NOx Emission ppm (corrected at 16 O2)
Combustion Efficiency
HHV 1,000kcal/m3 NH3 conc. 1,000ppm CH4
conc. 1.5
Gas Turbine Load
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Conclusions
The designed combustor is satisfactory for
1500 C-class gas turbine combustor under the
pressurized, rated load conditions. Main results
are as follows

• Stable combustion was maintained even in the case
  of 800kcal/m3 (HHV) as caloric value of the fuel.

• Combustion efficiency shows around 100 under
  operational conditions of 25 gas turbine load or
  higher.

• NOx emission could be decreased to 60ppm
  (corrected at 16 O2) or less in the case where
  the gasified fuel contained 1,000ppm NH3.

• Liner wall temperature was almost remained under
  850?, the allowable heat resistant temperature,
  under the rated load conditions.