Economic Evaluations of Energy Recovery options for oxygen- and enriched air-blown Texaco GCC power plants. Final report

This report presents the results of preliminary process design and economic screening studies of seven integrated Texaco-based coal gasification/combined-cycle power plant systems. Previous reports have indicated that the oxidant feed and hot gasifier effluent cooling units are the most costly items in the gasification system and, thus, hold the greatest possibility of being reduced. Therefore, the systems examined reflect combinations of two types of coal oxidant (98 percent oxygen and enriched air containing 35 percent oxygen) and four gas cooling options. Also presented is an eighth process design (without economics) of the most efficient of the seven systems under the more favorable ISO ambient conditions, rather than summer conditions. Except for the gasifiers and associated high-temperature heat recovery equipment, all of the combined-cycle designs in this report use commercially available components, including the gas turbines. The gasifier performances are based on extrapolations of the pilot plant gasifiers from mid- to the late 1980s. The high-temperature heat recovery equipment designs have not been demonstrated as full-sized equipment. The first and major objective was to determine whether or not oxygen-blown Texaco-based gasification combined-cycle power plants employing current technology combustion turbine (2000/sup 0/F), could produce electricity at a competitive cost to that produced in a conventional coal-fired steam plant using limestone scrubbers for SO/sub 2/ removal. When all the cases are compared and referred to earlier studies, it is concluded that oxygen-blown Texaco GCC plants employing current technology (2000/sup 0/F) combustion turbines produce electricity that is cost competitive with electricity produced by a conventional coal-fired steam plant with stack gas scrubbers designed to meet 1978 New Source Performance Standards.