Experimental Study On Arsenic Reduction By Copper In Gejiu Tin - Copper Polymetallic Deposit In

At present, separation of copper and arsenic is still a big problem in the field of mineral processing. A lot of researches on the mineral separation have been carried out for a long time by mineral processing workers both at home and abroad, and some new progresses and achievements have been made. But it is difficult to achieve effective separation for some disseminated closely and refractory ore with complex properties by the existing mature beneficiation process.Many of the existing beneficiation processes lack of systematic process mineralogy as guide, and the optimization and research of the process flowsheet structure and flotation reagents have not been carried out, resulting in series of problems such as lower copper recovery and excessive level of arsenic in copper concentrate. At the same time, most of the mines only pay attention to the development of the valuable minerals, lack of understanding the comprehensive recovery of the associated minerals, especially for the associated silver minerals, leading to serious waste of resources.In view of the above questions, a tin-copper polymetallic sulfide ore coming from Gejiu tin mine in Yunnan was chosen as the research object. The separation of copper and arsenic minerals and the strengthening recovery of the associated silver by flotation were carried out. Systematic study the influence of the process mineralogy, process flowsheet, grinding process, flotation reagents, pulp pH value and other factors on the separation of copper-arsenic and associated silver, and under the condition that the main metal elements were not affected such as tin, the purpose of separation of copper and arsenic was achieved, meanwhile the associated silver was also comprehensive recovered.In this paper, on the basis of process mineralogy, a large number of floatation experimental studies were carried out. Finally, "copper-arsenic iso-flotation and copper-arsenic separation in rough concentrate" process was adopted. During copper-arsenic iso-flotation stage, ethyl xanthate was chosen as collector, weakening the collecting ability for arsenopyrite and selective recovery of copper and silver minerals. During copper-arsenic separation stage, used lime and sodium humic acid as arsenic combined inhibitor and chosen LZ as strong selective collector of copper and silver, strengthening the recovery of copper and silver. Eventually the copper concentrate with a grade of 20.19% at the total recovery of 64.15% was obtained, of which arsenic grade of 0.42%, meeting the quality requirements of qualified copper concentrate with containing arsenic content less than 0.5%. The grade and total recovery of silver in the copper concentrate were 308.72g/t and 31.93%, respectively.