Análise termoeconômica de uma central de cogeração de uma indústria siderúrgica

Abstract

A steel-making company which has in its industrial field waste gases of internal processes available for power generation is the focus of this work. It’s a cogeneration plant operating on rankine cycle, with three closed feedwater heaters and one open feedwater heater, whose function is meet the factory demands of mechanical energy (for production of blown air and electricity) and thermal energy (process steam) The thermoeconomic analysis through cost allocation was applied using three thermoeconomic models (E Model, E&S Model and H&S Model) besides their variants for formulating the auxiliary equations (subproduct and multiproduct criteria) in order to determine the final products exergetic cost of the plant. The results were analyzed considering general aspects of thermodynamics and cogeneration that allowed the calculation of efficiencies, exergy destruction in equipments and plant performance indicators. Among applied models, the E&S Model presented inconsistent results according to thermodynamics and cogeneration while E Model and H&S Model were the most satisfactory assessment of steel-making company cogeneration plants. The E Model limitation is the inapplicability of total disaggregation of the plant