Design of components of a steam power plant and its exergoeconomic performance analysis

Abstract

This study reports on design parameter calculation of the components of a steam power plant and its exergoeconomic performance. The plant is designed with the help of Flownex software, where the component sizing is done considering the fluid flow and heat transfer aspects which is usually ignored in usual thermodynamic analysis. A one dimensional flow equation solves the velocity and the pressure drops in the pipes and other components. Components such as steam drum, bottom header, furnace, downcomer and riser tubes are considered in the boiler. A simple turbine element and a basic centrifugal pump element are used to model the turbines and pumps. The heat exchangers are designed considering those as a two-phase tank with one composite heat transfer and the required number of pipe elements. Among the heat exchangers, the condenser is found to be the largest. It was found that the size of the heat exchangers is not solely dependent on the heat transfer rate but also on the overall heat transfer coefficient. The boiler is the major source of exergy destruction and the condenser ranks the last in terms of exergy efficiency. The system has a thermal efficiency of 36.07% whereas its exergy efficiency is 32.85%. The boiler-SH shows the highest total cost rate of 2413.08 $/h and the total cost rate of the system including fuel cost is 9339.75 $/h.