COAL-GASIFICATION GAS CLEANUP

Coal gasification integrated with combined cycle power generation (IGC C) is an alternative technology to utilize coal for electric power gen eration. IGCC technology has a higher efficiency and lower sulphur emi ssions than that of conventional power generation by coal combustion. Under gasification conditions, part of the coal S and N is converted t o H2S and NH3, which have to be removed from the product gas before it s combustion in the gas turbine. Sorbents can be used to capture H2S a t the reactor temperature, or at a lower temperature after the product gas is partially cooled. Controlled combustion of coal gas can conver t NH3 to N2. Equilibrium calculations provide valuable information on gas cleanup as a function of operating conditions of the selected gasi fier technology and the type of sorbent being used.