Advanced steam cycles for light water reactors. Final report

Technical Report · Tue Jul 01 04:00:00 EDT 1975

OSTI ID:4171285

Mitchell, R C

An appraisal of the potential of adding superheat to improve the overall LWR plant cycle performance is presented. The study assesses the economic and technical problems associated with the addition of approximately 500$sup 0$F of superheat to raise the steam temperature to 1000$sup 0$F. The practicality of adding either nuclear or fossil superheat to LWR's is reviewed. The General Electric Company Boiling Water Reactor (BWR) model 238-732 (BWR/6) is chosen as the LWR starting point for this evaluation. The steam conditions of BWR/6 are representative of LWR's. The results of the fossil superheat portion of the evaluation are considered directly applicable to all LWR's. In spite of the potential of a nuclear superheater to provide a substantial boost to the LWR cycle efficiency, nuclear superheat offers little promise of development at this time. There are difficult technical problems to resolve in the areas of superheat fuel design and emergency core cooling. The absence of a developed high integrity, high temperature fuel for operation in the steam/water environment is fundamental to this conclusion. Fossil superheat offers the potential opportunity to utilize fossil fuel supplies more efficiently than in any other mode of central station power generation presently available. Fossil superheat topping cycles evaluated included atmospheric fluidized beds (AFB), pressurized fluidized beds, pressurized furnaces, conventional furnaces, and combined gas/steam turbine cycles. The use of an AFB is proposed as the preferred superheat furnace. Fossil superheat provides a cycle efficiency improvement for the LWR of two percentage points, reduces heat rejection by 15 percent per kWe generated, increases plant electrical output by 54 percent, and burns coal with an incremental net efficiency of approximately 40 percent. This compares with a net efficiency of 36--37 percent which might be achieved with an all-fluidized bed fossil superheat plant design. (auth)

• Research Organization: General Electric Co., San Jose, Calif. (USA)
• NSA Number: NSA-33-006686
• OSTI ID: 4171285
• Report Number(s): GEAP--20950
• Country of Publication: United States
• Language: English

Related Subjects

*BWR TYPE REACTORS-- SUPERHEATING
*PWR TYPE REACTORS-- SUPERHEATING
*SUPERHEATING-- ECONOMICS
210100* --Nuclear Power Plants--Power Reactors
Non- Breeding
Light-Water Moderated
Boiling Water Cooled
COAL
COMPARATIVE EVALUATIONS
EFFICIENCY
FLUIDIZED- BED COMBUSTION
GE STANDARD REACTOR
N77100* --Reactors--Power Reactors
Non-breeding
Light- water Moderated
Boiling Water-cooled
N77200 --Reactors--Power Reactors
Non-breeding
Light-water Moderated
Non-boiling Water-cooled
NUCLEAR SUPERHEATING
SUPERHEATERS