Exergetic, Thermal, and Fuel Savings Analyses of a 20.70-MW Bagasse-based Cogeneration Plant

ABSTRACT

A thermodynamic study of a 20.70-MW bagasse-based cogeneration plant in the Indian sugar industry located in Belgaum is presented in this article. Analyses based on first and second laws of thermodynamics using actual operating data are presented first to acquaint the reader with plant's components and operation. The primary fuel energy savings achieved by the cogeneration plant in comparison with that of separate generation plants is determined and discussed. Secondly using the combustion, flue gas and environmental data from the plant, an irreversibility study is outlined that estimates the loss of exergy in the plant's components. The component contributing most to the overall plant inefficiency is pinpointed. The results show that the plant's cycle performs with an energy utilization factor of 69% and exergetic efficiency of 28%. Because of the inherent nature of combustion irreversibility, the largest fuel exergy loss (about 70%) is noticed in the boiler.

Keywords:

• Cogeneration
• bagasse
• exergy
• efficiency