含砷、锡铁精矿煤基直接还原焙烧脱除砷锡试验研究

摘要

Experimental studies on removing arsenic and tin from As-Sn bearing iron concentrates in Huanggang, Inner Mongolia were performed by coal-based direct reduction roasting process.The effects of roasting process, roasting atmosphere and the dosage of chlorination agent on removal effects of As and Sn in the products were investigated.The results showed that As was removed by oxidation at the neutral roasting statge and Sn was removed with highly volatile chloride resulting from the reaction with chlorination agent at the reduction roasting stage.The comprehensive experimental results showed that under optimal conditions the grade and recovery of TFe in direct reduction iron products obtained by reduction roasting-magnetic separation both reached 88％, and the contents of As and Sn residuals were 0.03％ and 0.07％, respectively.%采用煤基直接还原焙烧工艺对内蒙古黄岗含砷、锡铁精矿进行了焙烧脱除砷锡试验研究.考察了焙烧工艺、焙烧气氛及氯化剂用量等工艺参数对产品中砷、锡脱除效果的影响.结果表明,砷主要是在中性焙烧阶段被氧化脱除,锡是在还原焙烧阶段与氯化剂反应生成易挥发的氯化物挥发脱除.综合试验结果表明,在优化条件下,还原焙烧-磁选得到直接还原铁产品中TFe品位及回收率均达到88%,As残余含量0.03%,Sn残余含量0.07%.