Investigation efficiency factors in Tabriz thermal power plant

In this study, the energy and exergy analysis of Tabriz thermal power plant in Iran is presented. The primary objectives of this paper are to analyze the system components separately and to identify and quantify the sites having largest energy and exergy losses. In addition, the effect of varying the reference environment state on this analysis will also be presented. The performance of the power plant was estimated by a component wise modeling and a detailed break up of energy and exergy losses for the considered plant has been presented. Energy losses mainly occurred in the condenser where ۴۴۶.۷۵۵MW is lost to the environment while only ۱۹۹.۶۵۴ MW was lost from the boiler system. The percentage ratio of the exergy destruction to the total exergy destruction was found to be maximum in the boiler system (۸۱.۱۲%) followed by the turbine (۹.۷۸%), and then the other components (۹.۱%). In addition, the calculated thermal efficiency based on the lower heating value of crude oil was۳۳.۱۴%, while the exergy efficiency of the powercycle was۳۱.۲۶%. For a moderate change in the reference environment state temperature, no drastic change was noticed in the performance of major components and the main conclusion remained the same; the boiler is the major source of irreversibilities in the power plant. Chemical reaction is the most significant source of exergy destruction in a boiler system which can be reduced by preheating the combustion air and reducing the air–fuel ratio.

Keywords:

exergy analyze , exergy efficiency , dead state , Tabriz thermal power plant , exergy destruction