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The OBF process is widely studied as an alternative ironmaking process, due to the social pressure of energy and environment at present. A comprehensive mathematical model of the OBF proces...

Ironmaking using an oxygen blast furnace is an attractive approach for reducing energy consumption in the iron and steel industry. This paper presents a numerical study of gas–solid flow in an oxygen blast furnace by coupling the discrete element method with computational fluid dynamics. The model reliability was verified by previous experimental results. The influences of particle diameter, shaft tuyere size, and specific ratio (X) of shaft-injected gas (SIG) flowrate to total gas flowrate on the SIG penetration behavior and pressure field in the furnace were investigated. The results showed that gas penetration capacity in the furnace gradually decreased as the particle diameter decreased from 100 to 40 mm. Decreasing particle diameter and increasing shaft tuyere size both slightly increased the SIG concentration near the furnace wall but decreased it at the furnace center. The value of X has a significant impact on the SIG distribution. According to the pressure fields obtained under different conditions, the key factor affecting SIG penetration depth is the pressure difference between the upper and lower levels of the shaft tuyere. If the pressure difference is small, the SIG can easily penetrate to the furnace center.

In order to reduce the energy consumption from iron and steel industry, decreasing coke rate by establishing oxygen blast furnace (OBF) ironmaking process is a favorable way. In recent years, many scholars and metallurgical workers from all over the world have made a lot of related work about this ironmaking process. The main content in this paper is as follows: The necessity, process characteristics and optimization research of OBF were introduced. The optimal OBF process were elected by the calculation of energy-mass balance mathematical model. In order to cope with the subsequent industrial test, theoretical calculation of the improved process is carried out. The process parameters under different oxygen enrichment rate 9, 19, 29%, and eventually reached 100% are calculated. Calculation results show that with the increase of oxygen enrichment rate, the recycling gas volume from both shaft tuyere and hearth tuyere were increased, the coke rate gradually is reduced and the coal rate increased gradually. After adopting the OBF ironmaking process the ironmaking costs and CO2 emissions can be greatly reduced.

DEM-CFD coupled mathematical model of oxygen blast furnace (OBF) is established. Then it is applied to study the gas-solid flow in OBF. The effects of burden motion state, particle size, auxiliary tuyere size and the ratio of injected gas flow rate to total gas flow rate on the injected gas distribution were investigated in detail. The results show that there are 4 moving regions in the OBF. The high particles velocity corresponds to the high porosity in furnace, so the injected gas can penetrate into the center in moving bed more easily than fixed bed. Both decreasing particle size and increasing auxiliary tuyere area will increase the injected gas ratio at the edge, but decrease at the center. Calculation results also prove that the ratio of injected gas flow rate to total gas flow rate is crucial for the injected gas distribution in the furnace.