二次砷碱渣清洁化生产技术工业试验

以锑精炼产生的含砷9%、含锑2%、含碱40%左右的二次砷碱渣为原料, 在液固比为3∶1、90 ℃以上搅拌浸出3 h, 过滤后得到砷锑渣和浸出液。在浸出后液中加入脱锑剂A, 在60 ℃条件下搅拌反应3 h, 过滤后得到锑酸钠。在脱锑后液中通入二氧化碳, 在45 ℃左右搅拌反应3 h, pH值达到中性后, 过滤得到碳酸氢钠; 在95 ℃以上条件下返溶碳酸氢钠, 产出碳酸钠。在脱碱后液中加入试剂B, 在55 ℃左右搅拌反应3 h, 过滤后得到无水砷酸钠; 脱砷后液返回浸出工序。产品锑酸钠中锑含量在40%左右, 碳酸钠中砷含量小于1.5%, 砷酸钠中砷含量在24%以上。二次砷碱渣清洁化生产技术实现了浸出后液中的砷、锑、碱的全分离, 对于环境保护及资源的综合利用具有重要的现实意义。

Commercial Test of Cleanly Production Technology of Second Arsenic-alkali Residue

By stirring the second arsenic-alkali residue for 3 h which contained 9% arsenic, 2% antimony and 40% soda produced in the process of antimony abstracting when the fluid solid ratio was 3 and the temperature was above 90℃, the leached liquid and arsenic-antimony slag was obtained after filtering. Through adding the antimony-removing reagent A into the liquid and stirring it at 60 ℃ for 3 h sodium antimonate was got after filtering. After removing the antimony, carbon dioxide was blown into the liquid, which was stirred for 3 h at 45 ℃ or so until the pH value was neuter, and then sodium bicarbonate was produced after filtering. Sodium carbonate was got after re-dissolving the sodium bicarbonate above 95 ℃. The reagent B was added into the soda-free liquid. Anhydrous sodium arseniate was got after stirring the liquid for 3 h at 55 ℃. The liquid was returned to the leaching process after arsenic was removed. The content of antimony in the sodium antimonate product reached to 40%. The content of arsenic in the sodium carbonate product was under 1.5%. The content of arsenic in the anhydrous sodium arseniate product reached to 24%. The cleanly production technology of second arsenic-alkali residue achieved the absolute separation of arsenic, soda and antimony in the lixivium. It had vital practical significance for the environmental protection and the resource's comprehensive utilization.