分银渣中有价金属综合回收试验探讨

Discussion on Comprehensive Recovery Test of Valuable Metals from De-silver Residue

为充分回收利用分银渣中的有价金属,针对某冶炼厂稀贵金属车间采用“半湿法—回转窑”工艺处理铜阳极泥所产生的分银渣进行了有价金属综合回收试验,分别对试验的熔浸、氧化、沉淀、造贵铅等4个阶段进行研究。研究成果发现:熔浸阶段当分银渣、片碱、硫化钠的质量配比为1∶0.5∶0.6时,金属锑和锡的浸出率分别达到99%和93%以上;采用质量分数为10%的H2O2,且其用量为理论值的3倍,反应时间为2 h进行氧化反应时,锑的沉淀率达到99.27%,产品粗锑酸钠含锑达到45.9%;利用石灰可以使锡以钙盐的形式沉淀,锡的沉淀率达到92.97%,沉淀产物为粗锡酸钙;在造贵铅试验中,片碱与滤渣的质量配比为0.4∶1时,有价金属的回收率均可达到98%以上。

In order to fully recycle and utilize the valuable metals in the de-silver residue,a comprehensive recovery test was conducted on the de-silver residue generated from the treatment of copper anode slime in the precious metal recovery plant of a certain smelter by using the"semi-hydrometallurgy-rotary kiln"process.The four stages of the test,including melting&leaching,oxidation,precipitation,and production of precious lead,were studied.The study results found that the leaching rates of antimony and tin can reach over 99%and 93%respectively while the mass ratio of de-silver residue,flake alkali,and sodium sulfide is 1∶0.5∶0.6 in the melting&leaching stage.Once hydrogen peroxide with a mass fraction of 10%H2O2 is used for oxidation reaction,with a dosage of 3 times the theoretical value and reaction time of 2 hours,the precipitation rate of antimony reaches 99.27%,and the coarse sodium antimonate product contains 45.9%antimony.Lime can be used to precipitate tin in the form of calcium salts,with a precipitation rate of 92.97%.The precipitate product is coarse calcium stannate.When the mass ratio of flake alkali to filter residue is 0.4∶1 in the test of producing precious lead,the recovery rate of valuable metals can all reach over 98%.