Utilization of the Exhaust Gas of a Gas Pipeline Compression Station to Generate Electricity

Abstract

In this study, an application of an Organic Rankine Cycle (ORC) in a natural gas compression station in Erzincan region is presented. Natural gas compression station (NGCS) uses a gas turbine to pressurize the natural gas for transportation. Waste heat of gas turbine can be utilized by an ORC which uses n-pentane as working fluid to generate electricity. A costs/advantages analysis of the implementation is performed. According to designing factors, the pressure of the natural gas at the inlet and outlet of the NGCS are 48 bar and 73 bar
respectively. Mass flow rate and temperature of the exhaust gas from the GT are 26.65 kg/s and 460°C respectively and it shows that a significant amount of heat is rejected to the ambient. By applying an ORC to the NGCS, the results show that; total gross power via organic turbine, annual energy savings and annual cost savings are 1,385 kW, 11,057,535 kWhr and 1,327,000 $ respectively. Furthermore the payback time is calculated 3.77 years. Generally in this study, by utilizing an ORC in a NGCS, it has been tried to reduce the transportation cost and environmental impact of NG transportation.