Study On Iron Removal Process And Thermodynamics Of Regenerated Copper Fire

China is a big consumer country of copper, but 75% of the copper concentrate and secondary copper for producing electrolytic copper are dependent on imports, which severely restrict the development of China’s copper industry. The recycle, refining and reuse technology of scrap copper is particularly important. The recycling difficulties of scrap copper lies mainly in the study of the regulation mechanism of impurity elements and refining process, the domestic current research have solved the problem of partial removal of impurities by practically the experience of the plant; More in-depth study of the regulation theory of related alloys element are wanted.In this paper, the raw material is secondary copper with high content of iron, and studied the thermodynamic conditions of impurity removal process through the oxidation refining and flux method, discussed the influence law of experimental results by different flux composition, holding time, refineries temperature and other melting process parameters, and validated the impurity removal reaction by material testing methods, finally discussed the iron removal results by different flux formulations through comparing software simulation and experimental data, then determine the optimum process parameters of iron removal with fire refining.(1)Combine with FactSage software calculated the activity of Cu-0.5Fe copper alloy on melting temperature:(1086.725 ℃)= 1.0018, derived activity coefficients component of Fe in binary alloys calculating by Gibbs-Duhem equation;calculated free energy of the reaction 2Fe + 2Cu2O+ SiO2= 2FeO·SiO2+ 4Cu is negative which ΔG1423 K=-2234925 J·mol-1; Determined the feasibility of SiO2 and oxidation refining of iron removal; Calculated the temperature of oxidation refining is 1150 ℃, and at this temperature the limit of iron removal is 0.0011 wt.%.(2)Compared A1, A2, A3, A4 flux formulations effect of iron. With the increase of holding time, iron removal efficiency of A1, A2, A3 flux formulations grow with basic linear, the iron content decreased rapidly in first 10 min, and then the reaction slowed down, effect of iron removal reached the maximum which iron content was 0.005% at 30 min. Slag phase analysis was used to confirm the occurrence of the reaction of SiO2 and FeO.(3)By Equilib module of FactSage software calculated the results of iron removal by different flux formulations, validated that 1150 ℃is feasible refining temperature for oxidation refining, which can achieve good results of iron removal. Theoretical calculations showed that the higher the temperature refining, the worse the effect of iron removal. The results also showed that the A3 flux had the best effect of iron removal and the highest amount of copper in slag. Considering the effect of impurity removal and content in copper slag, A2 flux had a better effect of iron removal and less copper losses, which is more suitable for actual production using, the quartz amount of A2 flux is 4% of total melt mass the formula is Na2CO3 :SiO2 = 1:1. It shows that if guaranteed the flux formulation, refining temperature and holding time, the content of iron in the copper alloy can be controlled by laboratory condition.