Mechanism Analysis And Recovery Of Copper By Flotation From The Copper Tailing In Dexing

For the development of the use of copper was historic,since the low copper grade and the various factors in actual production which led to a huge amount of copper tailings.Copper tailings of early stage has a higher grade because of the technical immaturity,although the recent low grade ore,but the technology is relatively mature led to lower grade of tailings.Because of the long-term storage of tailings,surface oxidation and other factors reduce the floatability of copper tailings,the properties of tailings are very different due to the geographical differences and different pre-treatment.In this paper,flotation experiment was implemented on the copper tailings from Dexing on the basis of mineralogical analysis,multi-element analysis was took by X-ray fluorescence spectroscopy and the result show that the copper grade is 0.139%.Laser particle size analysis showed that the content of-38μm is 65%,the fine-grained tailings have some adverse effect on the flotation.Mineral components was studied by XRD,the results indicated that he copper was mainly in the form of copper sulfide,there are some components of oxide copper minerals,gangue minerals are mainly silicates and aluminum silicate minerals.Disseminated relationship and surface topography are studied by EMPA,the results showed that there are some very fine particle size dispersion of chalcopyrite in the tailings,but there are some copper minerals and pyrite symbiotic or gangue mineral inclusions.Single factor test,orthogonal test、flow comparison test、open circuit test followed by closed-circuit test conducted on flotation of tailings,the results indicated that utilizing sulphuric acid for pretreatment led to higher copper recovery,by approximately 10%under the same conditions.The recovery can be improved by approximately 3%in the way of replacing Na2S by Na2S4.Finally choose amyl-xanthate、ammonium dibutyl dithiophosphate as the collectors of sulfide ore、salicylhydroxamic acid as collector of oxidized ore、MIBC as foaming agent、guar gum and carboxymethylcellulose(CMC)as depressor of gangue minerals.Finally the grade of concentration reach to 13.67%while the recovery of copper reach to 59.2%after the process of Pro-process by sulphuric acid-Vulcanized-Bulk flotation-Finely grind-Copper sulfur separation.The theoretical and experimental analysis of the difference of flotation result between terpenic oil and MIBC and utilizing sulphuric acid pretreatment led to higher copper recovery were conducted using foam analyzer and infrared spectroscopy respectively as supplementary tools.The difference of flotation result by different forthers mainly because of the inclusions of fine mineral and the difference foaming ability between MIBC and terpenic oil,and the phenomenon of sulphuric acid pretreatment led to higher copper recovery maybe due to the reaction between sulphuric acid and free-OH on the surface of mineral led to the reduce of free-OH on the surface,so that increased hydrophobicity led to easier flotation,and this reaction takes place in contact with sulfuric acid and free-OH not selective,thus sulfuric acid is added to improve the recovery rate while the grade of the product didn’t show a decline.