Thermodynamic and exergo-environmental assessment of the organic Rankine cycle and S-CO_2 Brayton cycle for heat recovery in a gas turbine

摘要

The general purpose of this study is to make feasible the recovery of waste heat in gas turbines. An integrated power generation system consisting of a gas turbine-powered by supercritical carbon dioxide closed Brayton cycle and organic Rankine cycle working with n-pentane is designed. The actual operating conditions of the combined system are examined thermodynamically to establish the limiting states. Thermodynamic examination is performed for all elements of integrated system. The total net power generation of overall system is found to be 2,789 kW. The energetic and exergetic efficiencies of combined plant are found to be 44.71 and 42.05, respectively. As a result of thermodynamic analyses, the irreversibility amount of system is also calculated and found to be 13,810 kW. System equipment with the highest exergy destruction is found in the heat exchangers with 56. The temperature and pressure of turbine inlet conditions have considerable impact on the whole system performance.