Numerical Simulation Of Gas Flow Field In The COREX Smelter-Gasifier

COREX is an alternative process of blast furnace, which is the first commercialized non-coking coal based smelting-reduction process. The COREX C-3000 in Baosteel is the largest set all over the world, it breaks a new path of non-blast furnace for ironmaking. In order to improve the capacity of the process and make full use of it, practical problems need to be deal with. Fundamental research on the process is necessary to study, publications about this are rarely found, especially on the melter-gasifier. In this paper, a 2-D static model has been developed to evaluate the gas-solid flow transport phenomena in the COREX smelter-gasifier, application of Computational Fluid Dynamics (CFD) combined with the porous media and multi-phase models are employed. Pressure distributions and velocity profiles are obtained, further more the effects of operational parameters on the transport phenomena in the smelter-gasifier were studied. The parameters studied were the particle diameter, porosity of the bed, charging manner, blasting velocity at the tuyere and bed height of the packed bed, pressures and velocity profiles under different conditions are obtained and also the effects of these parameters on the gas velocity field and pressure in the smelter-gasifier were analyzed, the results reveal:①The 2-D gas-solid flow model was established, the velocity profile and pressure distribution in the smelter-gasifier are obtained, the simulation results in line with the experiments results in related references, but there are lots of studies on this field in great request, especially the exact simulation of transport phenomena in the smelter-gasifier under muti-field coupling conditions, further researches about this are needed.②The particle diameter and the voidage in the packed bed influence the gas velocity and pressure distribution, the effect of particle diameter is significant, the gas velocity increases with the particle diameter increasing. When the particle diameter is in constant, the gas velocity at the smelter-gasifier increases slightly with the porosity increasing as porosity increasing because of the different charging manner.③Bed voidage variations may influence the gas flow in the melter gasifier. With the porosity of deadman increasing, the gas velocity in the hearth increases but the gas velocity in the packed bed and dome zone decrease. When the porosity of packed bed increases, the gas velocity in the hearth decreases and the gas velocity in the packed bed and dome zone increase. Controlling of the particle diameters of solid materials can optimize the gas flow in the smelter-gasifier.④The charging manner of the smelter gasifier significantly affects the gas flow field in the gasifier. The inverse"V"shape bed charging manner is preferred.⑤The blast velocity of gas in tuyere affects the gas velocity distribution significantly. The gas velocity in the smelter-gasifier can be adjusted by changing the blast velocity in the tuyere;⑥The height of the packed bed has little influence on the gas velocity in the smelter-gasifier, but much influence on the pressure distribution in the hearth. With the blast velocity increasing, the pressure in the furnace increases.