Research On The Process Of Removing Tin From Recycled Copper Melting And Refining

With the rapid development of economy,the quality demand for copper is growing yearly in China.This dissertation briefly describes the performance of copper and the impact of copper impurities on the performance.This dissertation describes the main methods of copper recovery,as well as domestic and foreign scrap copper smelting process and technology status,points out several recycled copper industry problems,and makes some suggestions to the development of renewable copper industry.In this dissertation,thermodynamics and kinetics of copper smelting process were analyzed and calculated,preliminary concluded:Standard free energy is negative in oxidation reduction reaction of the removed tin slag in the smelting temperature range,Thus redox reaction can occur.This dissertation makes calculation of volatilization in the process of smelting metal,it is concluded that impurities reducing value is very small which is caused by volatile and it is negligible.Through the analysis of tin in copper liquid activity,it is concluded that the main factors influencing the tin activity is the mole fraction of impurities in copper liquid.When the tin content is 0.5%,the residual concentration of tin is 0.0059%after oxidation refined.The specific content of tin scrap copper is prepared for expriments,SEM photographs of different morphologies of diatomite is shot.Through the experiment in the induction furnace,it is concluded that there is more microporous in the the microstructure of the diatomite,the ability of adsorption and remove will be stronger.Injecting refining and flux method was adopted in the workshop production expriments.Powder injection in refining is the mean that injecting the antioxidants and refining agent into copper liquid,this method can be increase mixing function,and the impurity will be dispersed in liquid copper,then the impurity and added solvent reaction sufficiently and generate slag,the slag will be removed by this way.The Tin can be removed 60%by dusting refining method,70%removal of iron,electrical conductivity can be increased by 5%.By flux method the tin can be removed by 25%tin,iron can be reduced to a very small amount,and there is no significant change about conductivity.Preliminary conclusions is obtained by factory expriments,the program is feasible.However,if it will be put into practical production,there are some practical problems to be solved.Test equipment is not suitable for actual production,so the equipment should be improved.Spray cans and blow tube need to be fixed as well as automate.The optimal time can be calculated so that the enterprise can be obtain maximize profits.