The mechanism of smelting reduction of chromite ore

对于ferro-chromium production from chromite ore and for chromium recovery from the slag formed during the decarburaization period of stainless steel-making。如果要增加减少铬浓度的有效性，则强烈地希望从实际和理论的角度澄清其减少机制。因此，对铬氧化物形态学的影响、减少剂和通量的影响以及对降低率的研究结果如下。铁熔体中的铬碳减少在一个粉末状态下非常缓慢，但当硅被添加到铁熔体时，它最好用于减少成型硅，在与ore反应时，将臭氧转化为液体泥浆。作为一个结果，削减是惊人的建议。The addition of fluxes such as silica， sodium borate and CaO-SiO-SiO-D22-D2 slag to chromite ore favored for the formation liquid slag and then the reduction rate of CryD22-D23-D2 was significantly promoted。Apparent activation energies of 200-300 kJ mol_

The reduction of CrィイD22ィエD2OィイD23ィエD2 is a basic reaction for ferro-chromium production from chromite ore and for chromium recovery from the slag formed during the decarburaization period of stainless steel-making. In order to increase the reduction efficiency of chromite ore, it was strongly desired to clarify its reduction mechanism from the practical and the theoretical points of view. So, the effects of morphology of chromium oxide, kinds of reductant and fluxes and temperature on the reduction rate were examined.The results obtained as follows. The reduction of chromite ore by carbon in iron melt was very slow in a powder state but when silicon was added to iron melt, it was preferentially used for the reduction to form silica, which reacted with ore to promote the dissolution of ore into liquid slag. As a result, the reduction was remarkably promoted. The addition of fluxes such as silica, sodium borate and CaO-SiOィイD22ィエD2 slag to chromite ore favored for the formation liquid slag and then the reduction rate of CrィイD22ィエD2OィイD23ィエD2 was significantly promoted. Apparent activation energies of 200-300 kJ molィイD1-1ィエD1 were obtained for the reduction of CrィイD22ィエD2OィイD23ィエD2 in molten slag and chromite ore by carbon or silicon.It was found from these results that the rate-determing step for CrィイD22ィエD2OィイD23ィエD2 reduction was the diffusion of Cr ion in chromite ore and the dissolution reaction.