Numerical Simulation of the HIsmelt Main Reactor for Optimizing Heat Transfer and Combustion at Different Hot Air Oxygen Contents and Daily Iron Production

Abstract

ABSTRACT The HIsmelt process uses pulverized coal and iron ore as raw materials, eliminating the need for coking and iron ore lumping compared to traditional blast furnace ironmaking processes, and significantly reducing CO2 and other pollutants emissions. However, as a new ironmaking process, the flow field, heat transfer, and combustion influencing factors of the main reactor are not resolved. Therefore, in this study, based on the consideration of fluid mechanics, heat conduction, and combustion reaction, a two-dimensional mathematical model was developed for the upper space of SRV (smelting reduction vessel), the main reactor of the HIsmelt ironmaking process, based on actual production data. The effects of hot air oxygen content and daily iron production on the velocity field, temperature field, and CO2 content field inside the SRV were investigated. The results show that as the oxygen content of hot air increases, the central airflow in the furnace develops downward, the gas temperature rises gradually, and the CO2 mass fraction generally shows a rising trend. When the daily output of iron increases, the velocity of airflow in the furnace decreases significantly, the gyratory zone moves upward; the high-temperature distribution zone in the furnace contracts; and the CO2 mass fraction decreases.