Chemical looping combustion (CLC) offers a possibility of separating the greenhouse gas CO2.An integrated gasification combined cycle based on CLC is discussed in this paper.In the system

NiO/NiAl2O4 is used as the CLC oxygen carrier and Texaco gasification process is selected.The system performance is simulated by using ASPEN software tool.The system efficiency is 39.61%HHV (41.55%LHV) and CO2 emission is 126 g·kW-1·h-1

assuming compressor pressure ratio 17

air reactor outlet temperature 1200℃

turbine inlet temperature (TIT) 1350℃ after supplementary firing

and cooling air fraction 12%.At TIT 1350℃

CO2 capture rate increases by about 23% and system efficiency decreases from 40.3% to 39.61% when the air reactor outlet temperature rises from 1000℃ to 1200℃.With the increase of TIT after supplementary firing from 1200℃ to 1500℃

system efficiency increases from 37.4% to 40.8% and CO2 emission rises from 3 g·kW-1·h-1 to 202 g·kW-1·h1.At a specific TIT there exits an optimum pressure ratio and the optimum pressure ratio goes up as TIT rises.