Combustion properties of coal gasification gas with CO2 dilution were investigated for a newly proposed IGCC power generation system with CO2 capture. In this system, the gasification gas is burned under high CO2 concentration atmosphere. In order to clarify the combustion properties of the gasification gas under such atmosphere, the laminar and turbulent burning velocities were investigated for outwardly propagating stoichiometric H2/O2/CO2 flames at the mixture pressures of 0.10 to 0.50MPa, comparing them with those of H2/O2/N2 flames. The unstretched laminar burning velocities of H2/O2/CO2 flames were smaller than those of H2/O2/N2 flames. The ratios of the turbulent burning velocity at the flame radius 30mm, utn(30mm) to the unstretched laminar burning velocity were found to be larger than those of H2/O2/N2 flames at the same turbulence intensity. Increase in the turbulence Karlovitz number and decrease in the Lewis number by the CO2 dilution might cause the increase in the ratio of the turbulent burning velocity to unstretched laminar one of H2/O2/CO2 flames.
