Coal-Fired, Closed-Cycle, Gas Turbine Cogeneration Systems

Cogeneration systems capable of utilizing our abundant coal resources are now especially attractive, as petroleum products are relatively expensive. However, coal-fired systems must inevitably cope with the abrasive and fouling character of the noncombustible ash content of all coals. This paper discusses the characteristics and cogeneration potential of the coal-fired, closed-cycle, gas turbine system (in which the working fluid is isolated from the products of coal combustion). Many closed-cycle, gas turbine thermodynamic cycles may be adapted to cogeneration. Parametric performance data are presented. The advantages of closed-cycle, gas turbine system/cogeneration cycles are explored, and comparisons are made between such systems and the more conventional steam-turbine based cogeneration cycles. The technology of closed-cycle fired heaters, including pulverized coal and fluidized bed firing is discussed. The key technical features of the fired heaters are discussed.