Industrial boiler flue energy-saving device and using method

The invention discloses an industrial boiler flue energy-saving device and a using method, and relates to the technical field of boiler flue energy-saving devices. The system comprises a boiler flue, a waste heat power generation assembly, a waste heat refrigeration system and a cooling coil. The waste heat power generation assembly comprises a first mounting plate, a plurality of wave-shaped heat conduction plates and power generation modules. The first mounting plate is fixedly mounted on the power generation mounting port; the plurality of wave-shaped heat-conducting plates are arranged on the side surface of the first mounting plate; the power generation modules are electrically connected in series; and the cooling coil is fixedly connected with a refrigerant water pipe in the evaporator. High-temperature flue gas exhausted from the boiler flue is used for supplying heat to the lithium bromide generator, the high-temperature flue gas in the boiler flue is utilized, and cooled refrigerant water enters the