Design and exergy analysis of waste heat recovery system and gas engine for power generation in Tehran cement factory

Abstract

Abstract Cement production is one of the most energy-intensive industries in the world which has high potential for heat recovery. This paper has studied the feasibility of technical design of WHR from a gas engine to use in electrical power generation for Unit-8, Tehran Cement factory. Two different approaches for energy recovery are proposed and compared. In the first scenario, which uses only one heat recovery boiler, total mixed gas enters the boiler before going into the pre-heater and grid cooler; however, in the second scenario, there is a vapor mixture that goes toward the steam turbine. In the current study, it is focused on analyzing and design of the gas engine which its calculations are done under FORTRAN codes, and the final configuration is made as a software. It should be noted that air conditioning of management building in the factory is involved in gas engine heat load calculations. The third analytical part considered in the codes is calculation processes of the combined heat recovery system coupled with a gas engine. Based on obtained results, the amount of recovered heat for the 1st and 2nd scenarios were 23931\u202fkJ/s and 21253\u202fkJ/s, respectively. In addition, the efficiencies of the power generation cycles for the 1st and 2nd scenarios were equal to 23.5% and 22.2%, respectively.