Compressed air storage with humidification (CASH) coal gasification power plant investigation

Technical Report · Thu Aug 01 04:00:00 EDT 1991

OSTI ID:5290078

Nakhamkin, M; Patel, M

A study was performed to investigate and develop a hybrid coal gasification concept which utilizes an air saturator (AS) with an integrated coal gasification/compressed air energy storage (CGS/CAES) plant. This potentially attractive concept is designated as AS/CGS/CAES. In this concept, the coal gasification system provides fuel for the combustors of the CAES reheat turbomachinery train. Motive air from underground storage is humidified by saturators and thereby provides increased power production without additional air consumption. The heat for generating the hot water utilized in the saturators is extracted from waste heat within the overall plant. Multiple alternatives were considered and parametrically analyzed in the study in order to select the most thermodynamically and economically attractive concepts. The major alternatives were differentiated by the type of gasifier, type of CAES turbomachinery, mode of operation, and utilization of waste heat. The results of the study indicate that the use of the air saturation in AS/CGS/CAES plants might reduce capital costs of coal gasification based power used in intermediate load generation by $300 to $400 per kilowatt. Furthermore, heat rates might also be reduced by almost 1.5 cents per kilowatt hour, a major reduction. The major cause of the reduction in electricity costs is a 50% reduction in the required gasification capacity per net kW. In addition to being a load management tool, AS/CGS/CAES concepts provide a method to operate the CGS and turbomachinery in a continuous mode, improving the operation and potentially the life expectancy of both components. 3 refs., 18 figs., 4 tabs.

• Research Organization: Electric Power Research Inst., Palo Alto, CA (United States); Energy Storage and Power Consultants, Mountainside, NJ (United States)
• Sponsoring Organization: EPRI; Electric Power Research Inst., Palo Alto, CA (United States)
• OSTI ID: 5290078
• Report Number(s): EPRI-GS-7453
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404 -- Coal
Lignite
& Peat-- Gasification
20 FOSSIL-FUELED POWER PLANTS
200102* -- Fossil-Fueled Power Plants-- Power Cycles
200105 -- Fossil-Fueled Power Plants-- Heat Utilization
200600 -- Fossil-Fueled Power Plants-- Economic
Industrial
& Business Aspects-- (1990-)
AIR
CAPITALIZED COST
COAL GASIFICATION
COMBINED-CYCLE POWER PLANTS
COMPRESSED AIR
COMPRESSED GASES
COST
ECONOMICS
ENERGY
ENERGY RECOVERY
ENERGY STORAGE
FLUIDS
GASES
GASIFICATION
HEAT
HEAT RECOVERY
HUMIDITY
MACHINERY
POWER PLANTS
RECOVERY
STORAGE
THERMAL POWER PLANTS
THERMOCHEMICAL PROCESSES
THERMODYNAMICS
TURBOMACHINERY
WASTE HEAT
WASTES