Waste Heat Recovery from Gas Turbine Flue Gases for Power Generation Enhancement in a Process Plant

摘要

To improve on-site power generation capacity and efficiency in process facilities, the thermal coupling of an industrial gas turbine cycle with a bottoming organic Rankine cycle for power plant flue gas waste heat recovery in a process facility is investigated. Using 1,1,1,3,3-pentafluoropropane (R245fa) as heat carrier in the Rankine cycle, 5.2 MW of additional electric power is generated, enhancing on-site power generation capacity and energy/exergy efficiency by approximately 23% and 6%, respectively. The overall energy and exergy efficiencies of the waste heat recovery system are estimated at 9% and 24%, respectively. Primary energy savings of approximately 1.3 million standard cubic feet per day (MMSCFD) of natural gas, or net annual operating expenditure savings of 1.6 million USD, could be realized with the proposed flue gas waste heat recovery system based on subsidized industrial electricity tariffs in the UAE, with 457 tons of avoided C02 emissions per year.