Numerical Simulation Of Gas Distribution In Oxygen Blast Furnace

Oxygen blast furnace is a new kind of technology in ironmaking industry. Compared to the traditional blast furnaces, oxygen blast furnace replaces the common air with almost total oxygen. There are many advantages of oxygen blast furnace. Not only in the structure of energy but also in the aspect of environment protection is the oxygen blast furnace better than the ordinary blast furnace. In recent years, with the improvement of environment awareness of people, more and more attentions have been paid to the research of oxygen blast furnace because of its unique function in decreasing the amount of carbon dioxide. There is a close relationship between the gas flow and the metallurgical process. So, it is necessary to study the gas flow to understand the whole process of ironmaking.Based on the different inner structures of zones in blast furnace, the porous model of the whole blast furnace has been built. Then the model has been used to study the gas flow. Because of the different ironmaking conditions between traditional blast furnace and oxygen blast furnace, it’s necessary to re-modify the model to make it applicative to the new oxygen blast furnace. Based on the theory of RTD, the percentage of different fluid models has been calculated. In condition of the utilization efficiency, the one which has the smallest percentage of dead zone has been selected as the best oxygen blast furnace.Secondly, the influence of different cohesive zone on the gas flow has been studied. The factors have been considered including the shapes of cohesive zone, the structure of cohesive zone. A lot of pictures related to velocity and pressure distribution have been plotted to help analysis the flow in blast furnace. We have found the shapes of cohesive zone including V, W and invers V shape that cause different gas flow phenomenon especially in the region adjacent to the cohesive zone. The cohesive angle, cohesive height, cohesive thickness also impacts the gas flow too. Besides, the porosity and diameter of the cohesive zone may make a difference in velocity and pressure distribution of the gas.Thirdly, several burden distribution parameters have been studied using the modified model to clarify the relationship between burden distribution and gas distribution. The parameters considered including the mass of ore and coke, the porosity variation along the axis and radius. A lot of conclusions have been reached. For example, when increasing the mass of coke, it will improve the velocity of the coal gas in the center of the blast furnace; when increasing the weight of the ore, it will decrease the velocity of the center gas. The change of the porosity along the axis does not change the velocity distribution any much. But the modification of porosity along the radius direction will change the velocity distribution significantly. The pressure in the blast furnace changed accompanied the change of burden parameters. Different burden parameters correspond to different phenomena.