According to the characters of condensing dehumidification,the energy efficiency method,material balance method and heat balance method were used to build an analytical model about the cascade use of cooling energy in blast furnace (BF) blower system.The actual data,which were collected from a steel works,were settled and then analyzed by means of the analytical model.The results show that the cooling energy in the steel works’ BF blower dehumidifying system is not fully used.For better use,the condensed water,with a production rate of 22.56 tons an hour at 10 ℃ in July and August,can be used in the condenser of one refrigerator after water treatment,and lower the cooling water temperature by 1 ℃.Meanwhile,it can enhance heat transferring and increase the cooling energy of refrigerating system by 352 kW.