Closed Dual Fluid Gas Turbine Power Plant without Emission of Co 2 into the Atmosphere

This paper describes a construction and characteristics of a coal-gas-burning high e ciency power plant which emits no carbon dioxide (CO 2 ) into the atmosphere. In the plant, CO 2 gas and superheated steam are used as the main and sub working uid, respectively, of a closed dual uid gas turbine power generation system. It is assumed that a coal gas whose principal compositions are CO, H 2 , CO 2 and CH 4 is burnt in a combustor using oxygen, and that CO 2 gas and superheated steam are used as the main and sub working uid of a turbine, respectively. Consequently, the constituent gases of the combustion gas become CO 2 and H 2 O. Thus, CO 2 gas included in the exhaust gas can be easily separated at the condenser outlet from the condensate (H 2 O). Most of recovered CO 2 is recycled as the main working uid of the turbine. In the plant, high-temperature turbine exhaust gas is utilized in a waste heat boiler to produce superheated steam which is injected into the combustor in order to improve power generation e ciency. It has been estimated that an electric power of 208 MW can be generated with gross thermal e ciency of 51.3 %. Power generating e ciency has been estimated to be 43.7 % since the electric power of 31.1 MW is required for producing the oxygen for combustion. The problem of liquefying CO 2 recovered has also been dealt with in the paper. It has been shown that the resultant power generating e ciency is estimated to be 39.0 % if the power for liquefaction of recovered CO 2 is taken into account.