| Copper has an important strategic position in the development of the national economy.China’s copper resources are dominated by small and medium-sized deposits,with low copper grades and complex accompanying elements.The characteristics of "small scale and low grade" not only restrict the production capacity of China’s copper mines,but also increase production costs.With the rapid development of China’s economy,the demand for copper resources is also increasing.According to relevant statistics,China has been the world’s largest copper consumer for 18 consecutive years,and the external dependence of copper concentrates has exceeded 70% for many consecutive years,posing a serious safety hazard to the national economy.Therefore,increasing research and development efforts on China’s copper resources is of great significance in alleviating the supply-demand contradiction of domestic copper resources and promoting sustainable development of the national economy.Yangla copper sulfide ore is a typical low-grade complex refractory copper ore,which is difficult to beneficiate.This paper takes Yangla copper sulfide ore as the research object,and conducts relevant flotation experiments based on the characteristics of the ore.Research on process mineralogy shows that the raw ore of this ore has a Cu grade of 1.08%,a Fe grade of 21.06%,and an S grade of 8.81%.The associated rare and precious metal elements Au and Ag have grades of 0.33g/t and 12.07g/t,respectively.The copper mineral in the ore is mainly chalcopyrite,which has a complex embedding relationship in the ore and is closely associated with pyrite and pyrrhotite,making it difficult to separate copper and sulfur.In addition,some chalcopyrite occurs in micro and fine grained states in the crevices of gangue minerals,making it difficult for some chalcopyrite to achieve monomer dissociation and difficult to recover.On the basis of process mineralogy research,a large number of experimental studies were carried out,and the flotation magnetic combined separation process flow of "copper sulfur mixed separation copper sulfur separation magnetic separation" was finally determined.The results showed that under the conditions of-0.074 mm in flotation fineness accounting for 80% and-0.038 mm in regrinding fineness accounting for 85%,24 K was used as the foaming agent,JD-1(modified xanthate)was used as the collector for copper sulfur mixing and sulfur separation,and KMY-1(lipid agent)was used as the collector for copper sulfur separation.Through small-scale closed circuit experiments,a copper concentrate with a copper grade of 20.02% and a copper recovery rate of 83.43% can be obtained.The gold and silver grades in the copper concentrate are 1.44g/t and 91.31g/t,respectively.A sulfur concentrate with an S grade of 44.39%,an S recovery rate of 47.29%,an Fe grade of 43.32%,and an Fe recovery rate of 18.75%can be obtained.The final sulfur grade of the sulfur concentrate and the total magnetic separation concentrate is 41.17%,and the iron grade is 44.48%.According to the small-scale closed circuit test process,industrial tests of the new beneficiation process and reagent system will be carried out after completing the transformation of the on-site process flow.Through continuous production,a copper concentrate with a copper grade of 19.58% and a copper recovery rate of 83.38% was obtained during industrial trials,with gold and silver recovery rates of 40.62% and 50.86% respectively.Additionally,a sulfur iron concentrate with an S+Fe grade of 85.54% and a recovery rate of 79.48% was obtained.According to relevant statistics,the copper recovery rate of copper concentrate has increased by 5.91% compared to the average value of the five years(2016-2020)before the experiment,and the application of the new process has reduced the grinding and flotation cost of the concentrator by about 0.47 yuan/ton.The application of the new technology has achieved good technical and economic indicators. |
