1. Advanced Gas Turbine Power Generation Technologies
Jinyue Yan
Luleå University of Technology (LTU)
Royal Institute of Technology (KTH)
Presented at Sweden-China Workshop on Energy R&D and Climate Change
Stockholm, November 14-16, 2001

2. Driving forces of power market
Source: International Power Generation, Vol. 21, No. 5, Sept. 1998
©J. Yan

3. What happens in Nature when energy provides services
What happens in Nature when energy provides services ? A “heat engine model”
Nature (Source)
What have we paid for the services?
Have we ever paid?
Forgot the nature?
resources
service/energy
Society
wastes
Nature (Sink)
Nature (Sink)
©J. Yan

4. When are you going to pay now or future ?
©J. Yan

5. Gas Turbine R&D Trends Efficiency Improvement
Reduce emissions including CO2
Integration with other advanced power generation technologies, e.g. fuel cells
Distributed power generation- Microturbine
©J. Yan

6. Fuel-based power plants - combustion engine based
Steam Turbine
steam as working fluid
max temp C
Gas Turbine
combution gases as working fluid
max temp > 1400C
Combined cycle: ST+GT
Hero Steam Turbine BC200
©J. Yan

7. Market of Gas Turbines and Turbines
Development of orders placed (MW) worldwide for hydrocarbon fueled power plants
(Langston, Global Gas Turbine News, IGTI, Vol. 36, No. 3, 1996)
? What are the drivers for the market:
low natural gas price
increased environmental legislation
increases in generating capacity have been required quickly and cheaply (competition)
? Fundamental drivers
Unit cost of electricity produced (Y) =
Plant operation and maintenance cost (OM)
+ capital and finance cost (C0)
+ fuel cost (cost of fuel () / (efficiency)
©J. Yan
P7010

8. (News) from Gas Turbine Manufacturers
ABB: (1994) GT24/26: simple cycle 38%, CC 58.5%.
GE: (1995) G and H-Technology, CC 60%.
Siemens-Westinghouse
Capstone(2000): Microturbine 30kWe (60kWe)
1998: 3 units
1999: 211 units
2000: 790 units
…….. Note:
1791: first gas turbine patent (John Barber)
1900: first gas turbine operated in France by Stolze
©J. Yan

9. R&D on Steam and Gas Turbines
Continue -->
Use overheads for Docent Presentations.
Annual Publications in “Steam Turbines” and “Gas Turbines” in the Last 30 Years.
Literature Searching Results from Ei – Engineering Index by Yan, May 10, Key Words: gas turbine, steam turbine.
©J. Yan
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10. Gas and Steam Turbine Efficiency Evaluation (McDonald, 1994)
©J. Yan

11. Efficiency vs turbine inlet temperature
Inlet Temperature
60% CC
©J. Yan
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12. Efficiency Improvement of Gas Turbine Cycles
Turbine Machinery Aerodynamic Advancement to improve compressor and turbine efficiency - CFD Code - Blading geometry - Casing surface treatment …...
Turbine Inlet Temperature Increases - Material technology - Cooling techniques
More advanced Cycles
©J. Yan
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13. Approaches for Gas Turbine R&D
Cycle innovation
Working fluids
Hardware
improvement
System integration
Approaches for Gas Turbine R&D
Integration
©J. Yan

14. Advanced Gas Turbine Systems
Combined cycles
Evaporative gas turbine (HAT) and STIG cycles
Reheat
Inlet air cooling
Microturbines (30kW-300KW)
Chemical Looping Combustion (CLC)
Kalina bottoming cycle
Chemical recuperation
Hydrogen combustion turbine
…...
©J. Yan

15. Recuperation
Reheat
Intercooling
Inlet air cooling
Heat recovery
Modification of System Configuration by Additions of Options to Simple Cycle.
©J. Yan

16. Solid Fuels Biomass, Coal, etc
Energy Sources
Processes
Product Outputs
Externally fired gas turbines
- System optimization & analysis
- Heat recovery subsystems
- High temperature heat exchange
- Topping combustion
Natural Gas Fuel
Evaporative gas turbines
- System optimization & analysis
- Humidification tower
- Transport characteristics
- Water recovery
Power +
Heat
Ammonia-water cycles
- System optimization & analysis
- Working fluids
- Economic analysis
- Thermophysical properties
Solid Fuels Biomass, Coal, etc
Power
Close cycles
- System optimization & analysis
- Working fluids
- Economic analysis
- Equipment sizing
Waste Heat
Chemical looping combustion
- System optimization & analysis
- Economic analysis
- Equipment sizing
- CO2 reduction
©J. Yan

17. Role of Heat Exchangers in GT Cycles/Applications
(REHEATER) STEAM GENERATOR
IGCC
HEAVY DUTY GAS TURBINE
COMB.
CYCLE
SIMPLE CYCLE
EvGT HAT
AERODERIVATIVE GAS TURBINES
STEAM GENERATOR GASIFIER
I.C. REFORMER
CHEM.
RECUP.
HAT EvGT
I.C. R.C. A.F. SATURATOR
INTER -COOLED COMB. CYCLE
I.C. STEAM GENERATOR
INTER
-COOLED
I.C.
COMBINED
SIMPLE
STEAM
GENERATOR
NO HEAT
EXCHANGER
SUPPLIMENT.
-FIRED
EFCC
PFBC
CLOSED
CYCLES
R.C. STEAM GENERATOR
HEAT EXCH.
SATURATOR
I.C. R.C. A.F.
STIG
PRECOOLERI.C.
R.C. HEATER
HTHx STEAM GENERATOR
CHEM. RECUP.
REFORMER
HEATER
©J. Yan

18. R&D on Evaporative Gas Turbines
A national R&D program, 1992: prestudy,
Team includes industrial companies and universities: Alstom (ABB), (Volvo), Vattenfall, Sydkraft, El-forskare, El-Kraft (Denmark), KTH, LTH, STEM.
Three blocks
Pilot plant: 600 KW simple cycle, EvGT started operation in 1998
Water Circuit of EvGT: water recovery, humidification, flue gas condensation ……
Advanced EvGT: Modifications of EvGT, future market and applications, EvGT+CO2, EvGT Cogeneration, …...
Other supporting projects: for example: thermodynamic properties of humid air (supported by STEM in another program: “thermodynamic processes for power generation“)
©J. Yan

19. EvGT (HAT) Cycle with Partial Flow Humidification
by pass air IC
fuel
air
Intercooler
REC
aftercooler AC H
ECO
water
EvGT (HAT) Cycle with Partial Flow Humidification
©J. Yan

20. Core Turbine: Volvo VT600 for Pilot EvGT Turbines
©J. Yan

21. ©J. Yan

22. ©J. Yan

23. ©J. Yan

24. ©J. Yan

25. Integration of advanced gas turbines with CO2 removal
Semi-closed cycles
Chemical Looping Combustion
Hydrogen Turbines
…...
©J. Yan

26. Marriage of Gas Turbines and Solid Fuels
Solid fuels: Coal, Biomass
Coal: 40 % of electricity based on coal in the world
Biomass: 17% of total energy supply in Sweden
Require: more efficient, cleaner, cheaper
©J. Yan

27. Solid Fuel Fired Gas Turbines - Clean coal technology
Integrated gasification combined cycle (IGCC)
Pressurized fluidized-bed combustion (PFBC)
Externally fired gas turbines (EFGT)
Direct solid-fuel fired gas turbine
Supercritical steam turbines (not gas turbine)
©J. Yan

28. Money?
Is it affordable?
©J. Yan

29. Strategy for R&D of Solid Fuel Power Generation Technologies
Integration of features
of different systems
Simpler integrated
system
Based on accepted
technology
IGCC
EFGT
PFBC
R&D Trends
Increase efficiency
Reduce cost
Lower environmental
Impact
Improve availability ……
©J. Yan

30. Motivation for the EvGT-BAT Cycle - Integration of three advanced Technologies -
- In order to use solid fuel, such as biomass, in a gas turbine it is necessary, either to use a gasifier, as in IGCC, or a HTHx, as in EFGT.
- But both technologies face some barries:
-The problem with integrated gasification systems is the size of the gasifier. It makes up the biggest part of the wohle IGCC power plant.
- A major problem at EFGT is the hot gas heat exchanger. Today's gas-gas heat exchanger, when also pressurized cannot withstand temperatures above 850°C. But todays advanced gas turbines have inlet temperatures above 1300°C.
- The result is, that top firing is necessary!!!
- In our EvGT-BAT cycle, three more or less new technologies are integrated; and thereby some of their technical problems can be reduced or even solved.
- The three technologies are steam based Biomass Gasification, externally fired gas turbine technology, and the evaporative gas turbine technology.
- By interating the EFGT technology with gasification and using a topping combuster, the size of the gasifier and the temperature of the HTHx can be reduced a lot.
- How thi works is easy to understand:
EFGT
EVGT-BAT
EVGT
Biomass Gasification
©J. Yan
P7010

31. Concept of EvGT-BAT Air Gas Turbine Furnace Topping combustor Biomass
-The high temperature heat exchanger does no have to achieve the TIT. Much lower temperatures are sufficient, e.g. 650 to 750°C, because the topping combustor increases the temperature to the TIT.
-And at the same time the flow of fuel gas is much less than i IGCC-plants, because the temperature of the compressed air is much higher than in IGCC-pants before entering the combustion chamber.
- The picture shows the compressed air is humidified, than heated in the recuperator and futher heated in the high temperature heat exchanger, with is located in the furnace.
- The furnace can be fired with coal as well, but in our case, we used only biomass as fuel. The turbine exhaust contains sill a lot of oxygen and sensibel heat, thus it can be used as combustion air in the furnace.
The black arrow brings us to the next main advantage of this system.
- In IGCC is an almost complete gasification required, because the char products are waste and therewith losses.
- In our system the conversion does not have to be complete, because the remaining char can be recycled in the furnace. This reduces the requirements on the gasification.
- A further feature that reduces size, is the use of steam based gasification and the location of the gasifier. The gasifier is a pipe reactor that is located in the furnace, just like a heat exchanger.
Gas Turbine
Recuperator
Furnace ~
Topping combustor
Biomass
EVGT
Cyclone
Biomass Gasification
Humidifier
Water
Biomass
©J. Yan
P7010

32. Theoretic volume of the gasifier, relative to a gasifier in IGCC
1:12
1:9
1:6
1:5
EvGT-BAT
I G C C
900
800
750
700
HTHx Temp. [C]
Reactor Volume [-]
- This figure doesn't show absolute values and it is only ment to give an idea about the potential of reducing size of the gasifier EvGT-BAT.
- We set the gasifier of an IGCC-plant as standart and calculated, based on the gas flow through it, how many times the gasifier in EvGT-BAT will be smaller.
-And this of course depends on the temperature of the HTHx.
- This great decrease in size is not just due to the use of an HTHx. In order to sustain the gasification, somehow, heat has to be added. This can be done by patial oxidation or by burning a part of the product gas. The first option reduced the heating value and the second option requires more gas production. So that the size of the gasifier increses.
- In EvGT-BAT [show the picture with the system???] the gasifier gets its energy from the soilid fuel furnace; thus no extra gas pruduction is necessary to sustain the gasification.
And this option does not exist in a conventional IGCC-system.
[Since we want to use a steam based gasification with water knock out, the heating value is about three times the one in IGCC, when partial oxidation is used.]
©J. Yan
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33. Future Power plant --> Clean energy plant
Integrated
large become larger
Distributed
small becomes smaller (PC power plants)
Flexible fuels
Multi-products
©J. Yan

34. Future Hybrid System Fuel Cells Gas Turbine Steam Turbine
Temperature
100 C
550 C
1200 C
Future Hybrid System
Fuel Cells
Combined Cycle
Gas Turbine
Steam Turbine
District Heating
Heat
©J. Yan

35. Future Technology Modules
Feedstocks
Fossil
- coal
- gas
- oil
Opportunity
- Biomass
- Municipal
waste
- Refinery waste
Fuel Upgrading
Process Options
Gasification
Combustion
Heat exchange
Separation
Catalysis
Fuel & Chemical Synthesis
Co-products
CO2-Rich Stream
Gas stream
cleanup
Output Options
Electricity
Chemicals
Transportation
Fuels
Syngas
Hydrogen Steam
Energy
Conversion
- Turbine
- Fuel Cells
Ash/trace Elements
CO2
©J. Yan

36. Thanks

37. Evaporative Gas Turbine Evaporative Gas Turbine
R&D on EvGT - System analysis and optimization
- water recovery
- air/water properties
- transport characteristics
R&D on Externally fired gas turbines:
- High temperature heat exchangers
- topping combustion
- furnace
- system optimization
Externally fired gas turbine
R&D on Closed cycles:
- system optimization
- economic analysis
- integration with other systems
Closed cycle
Evaporative Gas Turbine
Evaporative Gas Turbine
Gas turbine
Combined Cycles
Solid Fuels:
Biomass, Coal etc
Natural Gas
Rakine cycle
Kalina cycles
Products
Heat
Power
Kalina cycle
Kalina Cycles:
- cycle optimization
- properties of ammonia-water mixture
Fuel stocks
©J. Yan
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38. Electricity Generation - large contributes to environmental pollution
Coal fired steam turbine plants
Strategies
Increase efficiency
Reduce emissions
Shift to alternative fuels
Natural gas fired combined cycle
©J. Yan

39. - Reflection by the forgotten Nature
Challenges
- Reflection by the forgotten Nature
Shortage of resources
Environmental impacts:
particulate pollution, SOx, NOx, CO2
Human Society
Nature
Service, service, service
Nature
Resource, Resource, Resource
©J. Yan

40. Technology + Take care of Nature
Solution: Sustainable development
Nature
Human Society
Nature
Human Society
Nature
Human Society
©J. Yan
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41. Schematic of Biomass and Coal Co-fired EFCC with Externally Heated Gasification for Topping Combustion
Externally
Flue gas
heated
gasifier
Furnace
Cleanup
Moisture
Medium
system
biomass
Btu gas
Steam
Gas Turbine
Turbine
Air
coal
©J. Yan

42. The Development of Efficiency of Coal Fired Supercritical Power Plants
©J. Yan

43. Performance of Near and Long Term Coal & Power Systems (DOE, 1999)
©J. Yan

44. Externally Fired Combined Cycle Externally Fired Humid Air Turbine
skillnader sluten öppen, motivation
för- och nackdelar
Externally Fired Combined Cycle
Externally Fired Humid Air Turbine
Flue gas
After
Cooler
Eco
Furnace
Furnace
N-gas
(optional)
Recuperator
N-gas
(optional)
Steam
Turbine
Gas Turbine
Gas Turbine
Air
Humidifier
Air
Solid fuel
Solid fuel
Water
©J. Yan
P7010

45. EFHAT System Configuration
GAS TURBINE SUBSYSTEM
SOLID FUEL COMBUSTION SUBSYSTEM
air
top combustor
natural gas
combustor
compressor
solid fuel
generator
turbine
high temperature
heat exchanger
aftercooler
inter-
recuperator
cooler
humid air
heat exchanger
preheater
make-up
humidifier
economizer
water
preheater
combustion air
district heat network
condensing
heat exchangers
flue gas
flue gas from solid
HEAT RECOVERY SUBSYSTEM
from gas turbine
fuel combustor
©J. Yan

46. Electrical Efficiency
metallic
ceramic
Inlet Temperature of Gas Turbine
©J. Yan

47. metallic
ceramic
©J. Yan

48. Features of Biomass Air Turbine (BAT
Features of Biomass Air Turbine (BAT?) Cycle with Topping Combustion by Gasification
High efficiency
Topping combustion increases air temperature to the TIT of modern GTs.
Low cost
Metallic HTHx working at moderate temp.
Small gasifier compared to IGCC.
Using existing proven technologies, boiler at atmospheric pressure, gas turbine.
Technical features
Clean working fluid in gas turbine path.
Less volume-flow to turbine which means no/less modification needed for gas turbine design compared to IGCC.
Low emissions
Possible to use CFB with reduction of SOx and NOx.
High preheated air combustion in topping combustor to reduce NOx.
©J. Yan

49. Studies on EFCC EFCC Second-Law Case Study Parameters Analysis
©J. Yan

50. Subsystem Investigation
Studies on EFHAT
EFHAT
Case Study
Parameters Analysis
Subsystem Investigation
Heat Recovery System
©J. Yan

51. Outline History of Power Generation
Current Market and R&D Driving Forces - Challenge
State-of-Art of Gas Turbines
R&D of Gas Turbine Cycles - Chance
The Marriage of Gas Turbine and Solid Fuels (Coal and Biomass)
©J. Yan
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52. Inlet Temperature
HEAT Rate
1940
1950
1960
1970
1980
1900
2000
©J. Yan

53. History of World Energy Mix (DOE, 1999)
©J. Yan