Abstract
A CO2-capturing power generation system utilizing waste heat was proposed for increasing electric power generated in the daytime. In the system, relatively low temperature saturated steam is produced by using industrial waste heat at nighttime and is stored in a steam accumulator (AC). At daytime the steam from the AC is used as the working fluid of a gas turbine power generator in which generated CO2 is captured based on the method of oxygen combustion. The system has no process of compressing the working fluid gas, that is the process to be extremly power consuming one. Hence the system has high power generation efficiency. The generated CO2 can be captured by using oxygen combustion method, so that high CO2 capturing ratio near 100% as well as no thermal NOX emission characteristics can be attained. It has been shown through a case study of using waste heat generated in a urban waste incineration plant that the proposed system has total net exergetic efficiency of 31.1% and that the power generation efficiency is 51.1%, when the amount of utilized waste heat is neglected, being higher than 17.5% compared with that of the conventional power plant with the efficiency of 43.5%.
