Numerical simulation of innovative operation of blast furnace based on multi-fluid model

A multi-fluid blast furnace model was simply introduced and was used to simulate several innovative iron-making operations. The simulation results show that injecting hydrogen bearing materials, especially injecting natural gas and plastics, the hydrogen reduction is enhanced, and the furnace performance is improved simultaneously. Total heat input shows obvious decrease due to the decrease of heat consumption in direct reduction, solution loss and silicon transfer reactions. If carbon composite agglomerates are charged into the furnace, the temperature of thermal reserve zone will obviously decrease, and the reduction of iron-bearing burden materials will be retarded. However, the efficiency of blast furnace is improved just due to the decrease in heat requirements for solution loss, sinter reduction, and silicon transfer reactions, and less heat loss through top gas and furnace wall. Finally, the model is used to investigate the performance of blast furnace under the condition of top gas recycling together with plastics injection, cold oxygen blasting and carbon composite agglomerate charging. The lower furnace temperature, extremely accelerated reduction rate, drastically decreased CO2 emission and remarkably enhanced heat efficiency were obtained by using the innovative operations, and the blast furnace operation with superhigh efficiency can be realized.