Air cooler is mostly used for soft water cooling of blast furnace body. As the air cooler takes air as the medium and is greatly affected by seasons, the temperature of soft water entering the blast furnace will also change with seasons. The air cooler tube bundle is prone to corrosion and water leakage. When the heat exchange area of the air cooler is reduced, it is easy to increase the temperature of soft water in the blast furnace. With the improvement of ironmaking process and the increase of blast furnace utilization factor, the safe production and service life of blast furnace have been seriously affected.

At present, plate heat exchanger is used to replace air cooler in soft water cooling of blast furnace body. After the plate heat exchanger is used, the temperature of softened water entering the blast furnace is basically stable at 34~39 ℃ throughout the year, which is lower than that of air cooler when the flow rate of soft water and cooling water are both stable at 960~1200m/h.

The temperature of softened water in and out of the plate heat exchanger is determined according to the existing supply of soft water for the blast furnace. When the supply temperature of soft water is between 35 ℃ and 40 ℃, it is helpful for the production of the blast furnace. At the same time, considering the cooling capacity of the refrigerant water and cooling tower in summer, the temperature of softened water entering the blast furnace should be less than 40 ℃, and the temperature of softened water leaving the blast furnace should be less than 45 ℃, that is, the temperature of softened water entering the heat exchanger should be 45 ℃, and the temperature of softened water leaving the plate heat exchanger should be 40 ℃.

As the soft water system does not change except for shutting down the air cooler and merging it into the Banwu heat exchanger, the pressure loss on the soft water side of the plate heat exchanger must be less than the pressure loss on the soft water side of the original air cooler. The pressure loss on the soft water side of the original air cooler is less than 0.05MPa, so the pressure loss on the soft water side of the plate heat exchanger should be less than 0.05MPa.