根据低配碳直接还原—低温熔分工艺制备粒铁的技术思想,考察了渣相成分对熔分开始时间及熔分后铁收得率的影响.试验结果表明,随着CaO添加量的增加,球团熔分开始时间先减小后增加.当CaO添加量为2.0%时,熔分开始时间最短.n(C)/n(O)为0.8时,渣相熔点较低,流动性较好,有利于渣铁分离.综合考虑熔分时间、铁收得率及能耗等,实验室条件下的最佳工艺参数为n(C)/n(O)=0.8,CaO添加量为2.0%,反应时间40 min(熔分开始时间30 min+熔分时间10 min).该条件下铁收得率约为85%,铁粒中铁含量约为94%,金属化率达95%以上,可作为优质的电炉炼钢原料.
According to the technical idea of direct reduction followed by melting separation at low temperature based on ore-coal composite with low carbon ratio,the effects of slag composition on the start time of melting separation at low temperature and the recovery of iron were investigated.The experimental results show that,with the incresement of CaO,the start time of melting separation first decreases and then increases.The start time is shortest when CaO is 2.0%.When the n(C)/n(O) is 0.8,the melting point of slag is lower with a good fluidity.considering the melting separation time,the recovery of iron and energy consumption,the optimum parameters of this process in the lab include: n(C)/n(O)=0.8,CaO=2.0%,reaction time=40 min(start time is 30 min,and the duration time is 10 min).Under this condition,the recovery of iron is about 85%,the iron content in metal is about 94%,and metallization is more than 95%,which is a good feed for electrical furnace.