碱焙烧法综合利用低品位氧化锌矿

Comprehensive Utilization of Low-grade Zinc Oxide Ore by Alkaline Molten Roasting

采用碱焙烧法综合利用低品位氧化锌矿。将氧化锌矿与氢氧化钠混匀后焙烧。熟料水溶后过滤分离得到溶出液和滤渣,滤渣回收铁。碳分碱性溶出液制备ZnO、SiO_2产品。碳分溶液制备碳酸钠晶体或苛化碳酸钠溶液,得到轻质碳酸钙产品和氢氧化钠溶液,结晶后返回碱焙烧工序。整个工艺过程实现了低品位氧化锌矿中有价组元的综合提取利用,又实现化工原料的循环利用。碳分产品是ZnO、SiO_2和PbO_2的混合物,有待进一步探索分离手段。

The method of alkaline molten roasting was adopted for comprehensive utilization of the zinc oxide ore.The zinc oxide ore and industrial NaOH were m roasted after mixing.The clinker was digested and then filtrated to obtain solution and filter residue,which was used to recycle iron. The alkaline solution was carbonated by CO_2 to prepare ZnO and SiO_2 products.The Na_2CO_3 solution was used to prepare Na_2CO_3 crystal or was causticized by active lime milk to obtain light calcium carbonate and sodium hydroxide solution,which was crystallized and then returned for roasting process.The whole process achieves comprehensive extraction and utilization of valuable elements in low-grade zinc oxide ore,and realizes cyclic utilization of chemical material NaOH. The carbonation product was mixed product of ZnO,SiO_2 and PbO_2,and the further separation methods was needed to be discussed.