Comparison of five developed power cycles in the frame of waste heat recovery

Abstract

A thermodynamic comparison of five developed power cycles which are gas turbine (GT), Kalina (KAL), organic Rankine (ORC), gas turbine-Kalina (GT-KAL) and gas turbine-organic Rankine (GT-ORC) fed by the waste heat of an actual power plant system in Gaziantep is presented in this paper. The waste heat has a temperature and a pressure of 566 oC and 1.9 bar, respectively. In order to compare the thermodynamic performance of the power cycles, various parametric studies were performed by using the effect of the values of the pressure ratio of the cycles, the temperature of the exhaust gas, the logarithmic mean temperature difference of the heat exchangers and the turbine inlet and the outlet pressures in the given ranges. The net power output of GT, KAL, ORC, GT-KAL and GT-ORC were found to be 1095 kW, 955 kW, 585 kW, 1508 kW and 1594 kW, respectively. The thermodynamic results showed that the GT-KAL cycle has the best thermodynamic performance in terms of energetic and exergetic efficiencies such as 19.71% and 40.53%, respectively, as well as in terms of the highest net power production of 1594 kW from the available exhaust gas.