2016 Volume 56 Issue 9 Pages 1588-1597
Decreasing coke rate by establishing an oxygen blast furnace ironmaking process is an attractive method to reduce energy consumption in the iron-steel industry. An important feature of this process is shaft gas injection. In this work, a three-dimensional coupling model of DEM-CFD about OBF was performed to analyze the gas-solid flow in an OBF. The presence of melting zone and raceway were taken into consideration. The particles number is closer to the actual blast furnace by improving the coupling method. Three shaft tuyere configuration modes were proposed for studying the penetration behavior of the shaft injected gas (SIG). The solids distribution in furnace is discussed. Next, the effect of the SIG on gas pressure and the velocity vector was investigated. Finally, the SIG penetration behavior in both the radial and vertical cross-sections under different cases are investigated. The results showed that in conventional charging the solid phase volume fraction at the edge was larger than at the center in the shaft, which is conducive to center gas development. The effect of the SIG on the gas pressure and velocity vector was only observed in the vicinity of the shaft tuyere outlet. The rapid pressure drop and change of gas flow direction were observed above the melting zone. The shaft tuyere configuration mode where the number of shaft tuyeres and hearth tuyeres is equal and where the shaft tuyere was located between the hearth tuyeres is regarded as the optimum mode for a more reasonable heat distribution in the OBF.
