Technology research on deep utilization of flue gas waste heat for 9F grade gas-steam combined cycle back pressure heat supply unit

According to a set of large 9F grade gas-steam combined cycle back pressure heat supply unit, proposes a new integrated process that can deeply recover the waste heat of flue gas. The new process can increase the temperature drop of the primary heating network, using absorption heat exchanger at the heating station, and deeply recover the flue gas waste heat in the heat source through two-stage heating process. It can reduce the outlet temperature of flue gas to about 20℃, greatly improving the heating capacity of the heat source and the heating efficiency of the system, and can solve the problems of insufficient heating capacity(small thermoelectric ratio) and large gas consumption of gas cogeneration system. On premise of same gas consumption and output power, the annual heat supply of new system can increase by more than 32.2%, and the heating area can cover around 16.55 million square meters, comparing with the conventional heating system. Designs the technology process, and the analysis results of the yearly operating conditions show that the technology can achieve good energy conservation, environmental protection and economic benefits.