Research On Upgrading And Utilizing Of Exhaust Steam Waste Heat Of Turbine

Extraction steam heating and low vacuum heating are the mainly methods of currentcogeneration district heating. The new circulating water quality improvement technologybase on the absorption heat pump is endowed with potentials. The research is shown thatdecrease of cold source loss is the most effective method to improve the efficiency ofturboset.25MW extraction steam turbine units of Lindian is taken as examples to put forwardthe heat power and cool cogeneration technology n this paper. Firstly, Matlab is used tostimulate the circulating process of lithium bromide absorption heat pump to analyze theinfluence rule of parameters as the temperature of driving heat source on the thermalprocess. Secondly, theoretical calculation models of absorption heat pump and turbosetare established. The performance indexes of the extraction steam heating unit andcirculating water absorption heat pump heating unit in rated condition and maximumoperation cognition are contrasted and analyzed. In the rated conditions of scheme II,When the coefficient of heat supply of the heat pump unit amount to1.65, the thermalefficiency of circulating water absorption heat pump heating unit reach up to77.7%andthe heating load amount to83.47MW, which are22.43percentage and31.3MW higherthan those of extraction steam heating unit respectively. The heating capacity is improvedby60%. The heating load amounted to104.41MW under the condition of recovering allcirculating water low-temperature exhaust heat. Finally, a steam exhaust comprehensiveutilization system is put forward to the steam exhaust to determine power by heating(cooling) and improve the utilization of steam exhaust of turbine.The research is shown that the quality improvement and utilization of waste heat oflow grade circulating water by absorption heat pump could reduce the cold source loss ofthe unit and improve the thermal efficiency and heating load of the unit.