An innovative gas turbine/steam turbine coupled process is described and evaluated. The process consists of a gas turbine-driven PFBC of the recirculating type, in which urban refuse can be burnt with a minimum of preprocessing. The hot exhaust from the PFBC is then used in a waste-heat boiler to produce steam for a conventional reheat steam turbine powerplant. The proposed process is evaluated from a conventional First-Law (energy balance) point of view, and shown to have a higher limit efficiency than comparable existing cycles. A Second-Law (exergy-) analysis is then performed to show that the Second-Law efficiency of this coupled cycle is also higher than that of comparable cycles; this means that the proposed process effectively reduces the intrinsic irreversibilities in the energy-transfer subcycles. Finally, a conservative, conventional economic analysis is performed to compute the global economic plant parameters of engineering interest. The simple payback, among others, is shown to be in the range considered feasible for cogeneration cycles.

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