转底炉煤基直接还原铁矾渣回收铁锌联合工艺

Combined Process to Recover Iron and Zinc from Jarosite Residue by Coal-based Direct Reduction in Rotary Hearth Furnace

开发了转底炉内铁矾渣含碳球团直接还原—熔分回收铁、烟气回收次氧化锌的联合工艺,研究了工艺参数对铁矾渣中铁和锌综合回收的影响。最佳工艺条件为:碱度2.5,配碳比1.4,还原温度1 300℃,还原时间30min,金属化率达到98.47%,铁回收率为95%,在还原阶段锌的挥发率达到94%,熔分结束锌的挥发率接近100%。在最佳工艺参数下进行了Φ3.0 m转底炉中试试验,得到全铁含量44.50%,金属铁含量34.71%,金属化率78%的金属化球团,锌挥发率达到92%。

Direct reduction-melting combined process in rotary hearth furnace（RHF）address carboncontaining pellets of jarosite residue was developed to recover iron and zinc.The effects of parameters on recovery of iron and zinc were investigated.Under the optimum conditions including basicity of R=2.5,C/O=1.4,temperature of 1 300 ℃,time of 30 min,metallization rate is 98.47%,iron recovery rate is95%,zinc volatilizing rates is 94% at reduction stage and almost 100%in the end of melting.Pilot plant test was carried out to produce metallized pellets under the optimum conditions.Total iron content in metallized pellets is 44.50% with metallic iron of 34.71% and metallization rate of 78%,and zinc volatilizing rates is 92% in RHF（Φ =3.0 m）pilot plant test under the above mentioned optimum conditions.