Study On Comprehensive Utilization Of Secondary Resources In Copper Smelting Slag Flotation Tailings

Copper smelting slag flotation tailings as a huge secondary resources,its average utilization rate is only about 10%.The comprehensive utilization of these resources can not only produce considerable economic benefits,but also alleviate the lack of resources and reduce environmental pollution.In this paper,the atmospheric pressure acid leaching of flotation tailings and reduction roasting-magnetic separation recovery comprehensive utilization test technology are put forward.The material characterization and physicochemical analysis show that the flotation tailings granularity is mainly concentrated between 200 and 400 meshes,accounting for 67.55%of the total.Iron is mainly in the form of fayalite,ferrite,and partially magnetic iron and iron oxides,and the total iron content is 38.34%.Copper is mainly in the form of oxides and sulfides,and the copper content is 0.27%.Flotation tailings atmospheric pressure acid leaching process was used to investigate the effect of sulfuric acid concentration,leaching time,liquid-solid ratio,leaching temperature and oxidant dosage on copper leaching rate.The results show that the leaching rate of copper reaches 80.26%and acid consumption is 25.52kg·t^-1 under the conditions of initial acidity pH=3,leaching time 12h,liquid to solid ratio 4:1,leaching temperature 90°C,KCl O₃ content 1%and stirring rate 400 r·min^-1.Through the analysis of leaching process dynamics,the leaching of the flotation tailings is in accordance with the internal diffusion control model.The apparent activation energy of the leaching process is E=9.766 kJ·mol^-1.The leaching residue roasting-magnetic separation recovery technology is used to investigate the effects of coke addition amount,lime addition amount,roasting time,roasting temperature and cooling method on reduction roasting of iron recovery.The results show that the iron recovery rate is 92.82%,and the grade of reduced iron powder is 86.9%,when the amount of coke added is 20%of tailings leaching slag,lime addition content is 10%,calcination time is 90 mins,calcination temperature is 1200°C,and the calcined product is water quenched and the grinding degree?70%or more of the grain size?is less than 0.047mm.The iron oxides that react during the reduction roasting process are mainly FeO,Fe₃O₄,Fe₂O₃,and Fe₂SiO₄.When CaO is added and the roasting temperature is greater than 1100K,the degree of difficulty in reduction of the iron oxides during reduction roasting is:Fe₂O₃<Fe₃O₄<Fe₂SiO₄<FeO.Using copper sulphate,sodium sulfide and leachate as raw materials,explored a testing program for preparing Cu₂S by a method of reaction precipitation-high temperature melting reaction.The scheme is simple in process and low in preparation cost.Through XRD and SEM-EDS analysis of the Cu₂S powder,verifying that the purity of produced samples is high,particles are smooth and clean,and the smelting and crystallization process is fine.