Advanced Power Generation Using KRW Gasifier Technology
Publication Date: 2012-Jun-06
The IP.com Prior Art Database
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ADVANCED POWER GENERATION USING KRW GASIFIER TECHNOLOGY
I . N. Banchik
S. K. Jain
The M. W. Kellogg Company
Three Greenway P1aza Houston , Texas 77046-0395
Prepared f o r Presentation a t
The American I n s t i t u t e o f Chemical Engineers
1989 Annual Meeting
San Francisco, California
November 5-10, 1989
Session 90 - Advanced Combustion f o r Power Generation
Copyright 8 The M. W. Kellogg Company
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The purpose o f this paper is to compare the performance of an integrated gasification combined cycle (IGCC) facility using KRW gasifiers under two scenarios; (1) oxygen blown gasifiers with a typical "cold gas cleanup" system and (2) air blown gasifiers with a hot gas cleanup system. Hot gas cleanup will include hot particulate removal and hot desulfurization, both inbed with limestone and external polishing with zinc ferrite. The advantages o f the two schemes will be discussed and key differences between the two flow diagrams will be identified.
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AIR BLOGlN GASIFICATION WITH HOT GAS CLEANUP
The following section describes a single train in the gasifier island of an
IGCC facility which utilizing the advanced KRW gasification technology with hot gas cleanup to produce a low-Btu fuel gas which may be fed to a combined- cycle power plant modified to be integrated with the KRW gasifier. A block flow diagram of the overall plant, Figure 1, i s included. The gasification system includes hot removal of particulate and sulfur compounds from the fuel gas. Desulfurization is accomplished by limestone/dolomite injection into the KRW fluidized-bed gasifier and polishing desulfurization in external fixed bed desulfurizers with zinc ferrite; final particulate removal is effected by a high efficiency cyclone and a ceramic filter. Because the operations are carried out at elevated temperatures, the inefficiency and capital cost associated with other systems necessary to cool the gas, and then reheat it are eliminated. Further, since the gas is kept above its dewpoint during all phases of the process, process condensate is eliminated and water effluents consist only of conventional streams such as steam drum blowdown, cooling tower blowdown, site run-off, and sanitary sewage.
The plant is divided into five process areas:
Oxidant Compression and Supply
Gas Conditioning External Desulfurization
Process flow diagrams, Figures 2 through 4 are provided to facilitate understanding o f the detailed description of each section which follows.
Coal, sized to 2 x 0inch, is delivered from coal receipt and storage to the coal feed bin, from which it is ground, dried and classified in the coal preparation system. The mill is fed by gravity from the feed bin, and hot flue gas from the sulfator is routed to the dryer to reduce the moisture content in the coal to 5 w t %.
Prepared limestone i s delivered by pneumatic truck to the plant site and stored in a silo. As with...