Emission control exploring the energy and exergy analysis for turbines of a 500 MW coal-based conventional power plant

Abstract

This work considers an analysis using energy and exergy of turbines for a coal-based conventional steam power plant of 500 MW under the Damodar Valley Corporation (DVC), India to optimize its operating conditions. An effort has also been made to control the environmental emission of different gases from the plant. Hence, a control volume is assumed consisting of a high-pressure turbine (HPT), an intermediate turbine (IPT), and a low-pressure turbine (LPT) of the plant. A thermodynamic-based model is considered in determining the performance of turbines in the power cycle under various unit loads (60%, 80%, and 100%). This analysis includes a prediction of energy, then exergy, and related irreversibility of flow stream to and from said control volume under the unit load conditions. The improvement in heat rate of the turbine with an increase in load is also estimated. As found, the heat rate reaches a minimum when the plant operates at higher unit loads (80% and 100%), which is an economical condition of operation. With the basis of the improved heat rate, a reduction in coal consumption, plant ash generation, also SO2 and CO2 emissions by the plant are estimated.