抄録
The present paper discusses the performance analysis of a combined power generation system driven with syngas from coal gasification processes. The system, consisting of a gas turbine combined cycle and a solid oxide fuel cell, is targeted for the numerical analyses. The typical compositions of gases obtained from oxygen-blown and air-blown types coal gasification plants are adopted for fuelling the combined system in the present investigation. Throughout the numerical analyses, the effects of the coal-gasified fuel composition on the power generation performance were clarified. The change of fuel composition, which is caused by the different coal gasification process, does not significantly affect cell performance. The fuel flow rate is larger in the case of the air-blown type compared to the oxygen-blown type. Regarding the air-blown type, the much larger fuel flow rate is unavoidable, since the fuel includes the large amount of nitrogen. This causes as well as the gas turbine and steam turbine outputs and the power consumption of the fuel compressor being larger in the case of the oxygen-blown type compared to the air-blown type. The present estimation leads to power generation efficiency of about 61% could be achieved in the combined power generation system.
