Pilot plant gasification

The work on catalysis reviewed thus far does not include either gasification at elevated pressures or the use of volatile coals. The bench-scale work now reported compares the catalytic activity of various additives in the gasification of volatile coals with steam under pressure and studies other process parameters of interest such as gasification temperature, type of contact with the catalyst, degree of gasification, and repeated use of catalyst. Results of pilot plant gasification tests using additives are also reported. 

Consequently, two semicommercial pilot plants have been operated for 1.5 years. One plant, designed and erected by Lurgi and South African Coal, Oil, and Gas Corp. (SASOL), Sasolburg, South Africa, was operated as a sidestream plant to a commercial Fischer-Tropsch synthesis plant. Synthesis gas is produced in a commercial coal pressure gasification plant which includes Rectisol gas purification and shift conversion so the overall process scheme for producing SNG from coal could be demonstrated successfully. The other plant, a joint effort of Lurgi and El Paso Natural Gas Corp., was operated at the same time at Petrochemie Schwechat, near Vienna, Austria. Since the starting material was synthesis gas produced from naphtha, different reaction conditions from those of the SASOL plant have also been operated successfully. 

Note that the methanation section is the last processing step in the HYGAS pilot plant, and it depends on the steady-state troublefree operation of the preceding steps (the gasification reactor, amine purification, and caustic wash sections for cleanup sulfur removal) before it can be brought on-line. 

Process scheme of the supercritical water gasification pilot plant at FZ Karlsruhe. (Reproduced from Boukis, N., Galla, U., Diem, V., and Dinjus, E., Science in Thermal and Chemical Biomass Conversion, CPL Press, Victoria, 2004, 975-990. With permission.)... 

Bi-Gas [Bituminous Gas] A coal gasification process using a two-stage, entrained-flow slagging gasifier. Developed by Bituminous Coal Research. A 120-tons-per-day pilot plant was built in 1976 at Homer City, PA, under sponsorship from the U.S. Energy Research and Development Administration and the American Gas Association. 

Coalcon A coal gasification process using a fluidized bed operated with hydrogen. Developed by Union Carbide Corporation and the Chemical Construction Company, based on work on liquid-phase hydrogenation completed by Union Carbide in the 1950s. A 20-ton per day pilot plant was operated in the 1960s, but a planned larger demonstration plant was abandoned because of cost. 

Synthane A coal gasification process using steam and oxygen in a fluidized bed. An unusual feature is the large volume of hot gas recycled. Developed by the U.S. Bureau of Mines from 1961. A pilot plant, designed by the C. E. Lummus Company, was built at Bruceton, PA, in 1976. 

The MHI gasification technology has been tested in Nakoso (Japan) in two pilot-scale gasifiers. A new IGCC project has been started that is a 250 MW air-blown IGCC demonstration plant located in Nakoso, where the former pilot plants were based, and will process up to 1500 ton/day of coal, which is about nine times more than the former 200 ton/day... 

Table 2.11 Gasification Technology Demonstration/Pilot Plant Scale... 

---