The thermal power plant is rich in waste heat resources, and there is a phenomenon of "white feather" caused by the exhaust of boiler flue gas into the atmosphere. Domestic and foreign scholars have carried out a lot of research on the utilization of waste heat of flue gas. Absorption heat pump is widely used in the field of district central heating and cooling for energy level lifting device driven by waste heat. The regenerative, multi-effect, multi-stage and compression-absorption composite absorption heat pump technologies used in the field of waste heat recovery was reviewed. A flue gas waste heat recovery system consisting of a two-stage absorption heat pump, a temperature rising compression absorption coupling heat pump and a three-stage flue gas heat exchanger was proposed. The system is based on the principle of use of flue as waste heat energy cascade, reducing the flue gas from 145℃ to below 40℃, and obtaining a heating network hot water above 70℃, which can effectively improve the energy efficiency and reduce the "white feather" phenomenon.
