Exploration Of Energy Saving Ways In Ironmaking Process

As one of the basic industries of all industrialized countries in the world,iron and steel industry is an important symbol to measure the comprehensive competitiveness of the country.Ironmaking process is the upstream process of metallurgy,and blast furnace ironmaking is in the dominant position,but it existing some problems such as huge energy consumption,heavily dependent on coke and low utilization rate of heat energy.This paper aims to realize the energy saving and consumption reduction in the whole industry chain of the iron and steel industry,two dimensions are explored:Improvement of ironmaking process,high efficiency recovery and high value utilization of heat energy in ironmaking process.The results provide some reference for the exploration of energy saving methods in ironmaking industry.In the respect of improvement of ironmaking process,the model of reaction and energy in blast furnace was built,including the change of reaction heat,temperature distribution,concentration distribution,the change of physical form,mass transfer,heat transfer and the change of reaction rate.The problems of blast furnace process today and improved technology were summarized,the energy balance of blast furnace and the cost structure of ironmaking system were calculated,and by this method,the exploration direction of improving reaction efficiency,reducing coke dependency and recovering waste heat from by-product were put forward.In the respect of efficient recovery of heat energy in ironmaking process,the heat transfer process of molten slag when granulating was analyzed.The solidification process and granulation process of molten slag were simulated by Flunet,by this method,get the result that the optimal operating conditions of granulation are under nozzle pressure 0.2 MPa,cooling speed 50 m·s^-1,initial air temperature 473 K.At the same time,the trajectory of the solidification process,the changeof temperature and the necessary operation are obtained.In the respect of high value utilization of heat energy in ironmaking process,the influence factors of air supply temperature in hot blast stove were studied.Three schemes for increasing the blast temperature of hot blast stove were put forward based on defects in existing technology.Through the analysis and comparison with the existing advanced technology,highlights the advantages of the scheme:that is tosay,the heat recovery of metallurgical slag and heat energy utilization for hot blast stove are combined,in order to realize high value,high efficiency and low cost of whole process and system.