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Show WASTE GASIFICATION BY THE TEXACO GASIFICATION PROCESS Lisa A. Davis, Jamie E. Miranda, G. Neal Richter and John S. Stevenson Texaco Inc. Montebello Research Laboratory The Texaco Gasification Process (TGP) is generally considered to be the leading commercial, second generation, gasification process. Recently, the 100th plant using this technology was started. These plants have used feeds ranging from natural gas to asphalt and coal to produce chemicals, hydrogen, clean energy and electricity. In all of these applications, the most stringent environmental discharge requirements can be met. Particularly noteworthy, are several recent commercial plants that gasify coal to make ammonia, chemicals and, in the world's first Integrated Gasification Combined Cycle (IGCC) plant, electricity. In a number of these plants, petrochemical by-products and waste oils have been used as feedstocks. In one particularly interesting case, a plant gasified used motor oil to manufacture ammonia. Currently, the use of the TGP is being expanded to include the conversion of a larger range of wastes to useful products. In recent pilot plant operations, sewage sludge, from municipal waste water treatment, and oil field production wastes have been gasified successfully. The TEXACO GASIFICATION PROCESS (TGP) The TGP is a partial oxidation gasification process that uses an entrained flow configuration, and is operated in the slagging mode when ash containing feedstocks are used. Normally, oxygen is used as the oxidant, although air can be utilized. The ratios of the feeds are carefully regulated, and are kept in a range that leads to a highly reducing atmosphere. Carbon conversion in excess of 95% is normal, and in many cases can exceed 99%. The process can operate at high pressure. Because of the extreme conditions, high temperature and pressure, only a few, simple products are found, primarily CO and H2 • Sulfur is converted to H2S and COS, compounds that can be readily removed from the gas by conventional technologies. Details of the nature of the process, its operation and how it compares to the other classes of gasification processes that might be used, have been given in several earlier papers (1,2,3). - 1 - |