CO_2回収型高効率IGCC用クローズドサイクルガスタービンの開発: 排気循環ガスの分割供給による燃焼促進

摘要

排気循環によるガス化燃料?O2量論比燃焼クローズドサイクルガスタービン燃焼器を対象に，燃焼促進を図る希釈剤の供給方法について二段反応器モデルを用いた反応解析により検討した。その結果，希釈剤を分割して供給することにより一次燃焼領域の燃焼温度を調整して燃焼促進を図り，燃焼効率を向上できることがわかった。%Oxy-fuel IGCC (integrated coal gasification combined cycle) power generation employing the oxygen-fired, semiclosed cycle gas turbine with exhaust recirculation enables the realization of highly efficient, zero-emission power generation. In order to realize the oxy-fuel IGCC, we have to develop the combustion promotion technologies of the CO-rich gasified fuel/oxygen-fired stoichiometric combustion with recirculated exhaust. In this study, the effects of the recirculated exhaust split supply in gas turbine combustors on the emission characteristics have been examined through numerical analyses based on reaction kinetics with multistage reactor models of combustors. It was clarified that the fuel oxidation reaction rates increased and the chain initiation reaction in the primary combustion zone was hastened by the recirculated exhaust split supply, and then combustion efficiency improved.