Research On Comprehensive Recovery Of Silver Form High Temperature Acid Leaching Of Zinc Smelting Slag Form Inner Mongolia

At present, the recovery of silver from the hydrometallurgical slag has become an important way to silver production.Conventional methods of silver zinc leaching residue basically can be effectively recovered by flotation, and to achieve industrial production.With the technological development of hydrometallurgy, high temperature and high acid leaching method greatly improves the leaching rate of zinc and other valuable metals leaching rate.However, the silver was enriched in the slag so that it was not recycled.The sample was taken from Inner Mongolia zinc smelter company uses high-temperature high-acid leaching of zinc dross residue.In this paper, I made a detailed study on the material composition of the leaching residue was made.The water-soluble substances in the leach residue are mainly zinc alum and The main material of leaching residue is water jarosite(Fe[SO4]?H2O).Followed by,the leaching residue contain colloidal silica and zinc(Pb), iron oxide, and the residual debris of some minerals(hematite, zinc, iron spinel, feldspar, quartz, etc.).The silver leaching residue containing about 240 g / t(40.93% after removing the residue soluble silver-containing around 400g/t). MLA conducted mineral spectroscopy analys is shows that independent silver mineral of leaching residue contain chlorargyrite 、acanthite 、 stromeyerite..Other silver sporadic presence in the surface of various mineral leaching slag,some of which exist in the surface of tetrahedrite, covellite,chalcopyrite and sphalerite and other copper minerals, lead, manganese hard, zinc oxide, silica and other minerals also contain part of the silver.The main objects of silver is associate with manganese, copper minerals and sphalerite.By studying the material composition and the occurrence of silver of the leaching slag, we determine determine a reasonable flotation process. By single factor test conditions for testing and open process optimized testing,we ultimately determine the optimal flotation process.Under optimal reagent system condition,by "a fast floating a rough two fine two sweep" of the closed process,we can receive one silver concentrate that contain silver3087 g / t, 5.67% silver recoveries and another silver concentrate that contain silver2186g/t,61.23%of the silver concentrate.Comprehensive grade of silver concentrate contain silver 2242 g / t, recovery 66.9%,effective recycling of the slag silver mineral.By acting on the mechanism of sodium hexametaphosphate and colloidalchemistry DLVO theory draws a potential graph of interaction between particles in the slurry after adding potential hexametaphosphate,we know that the Hexametaphosphate is composed of multiple(20~100)PO3- polymeric the long chain polyphosphates. It can be ionized strong electronegative ion,which can form a complex with all the metal cations.After added sodium hexametaphosphate in the slurry, while The distance between the particles is 2~4nm, between the particles appear larger barrier.when the particles close to each other, presence greater repulsion between them,so the pulp in a decentralized state.