System for preheating cold air required by combustion of hot blast stove by waste heat of slag vertical mill

The utility model discloses a system for preheating cold air required by combustion of a hot blast stove by waste heat of a slag vertical mill, which comprises a system exhaust fan, a heat exchanger air inlet pipeline, a control valve, a pipeline heat exchanger, a cold air valve, a heat exchanger air outlet pipeline, a hot blast stove air blower, the hot blast stove, a hot air pipeline, the slag vertical mill and a bag type dust collector, the output end of the system exhaust fan is connected with the heating medium input end of the pipeline heat exchanger through the heat exchanger air inletpipeline, the control valve is fixedly installed on the heat exchanger air inlet pipeline, and the cold air valve is fixedly installed at the cold medium input end of the pipeline heat exchanger. Waste heat which is not utilized by the grinding tail is introduced into the pipeline heat exchanger, waste gas is directly exhausted into the atmosphere after cold air needed by entering the hot blast stove is heated, heated hot