Basic Study On The Process Of Moderate Dilution Copper Slag By Blowed And Stirred Gas

The copper resources of our country is very meagre,The characteristic of the existing copper resources is by low ore grade,less rich ore,lean ore,and selecting more difficult,the 0.3%?0.4%of the copper mine has been mined using which lead to our country need to import a large amount of concentrate copper every year;At the same time,the annual copper smelting will produce large amounts of copper slag,Copper content in copper slag is usually over 0.5%,iron content over 40%,therefore,the comprehensive recovery of copper slag of copper,iron,etc of valuable elements has the vital significance.Currently,the methods of industrial dilution processes of copper slag include mineral separating method and fire dilution.Cu-Fe resources of the copper slag can be effectively recovered by slow cooling iron ore dressing method.But large area is needed by the method,and latent heat of copper sla can't be effective utilization.The recovery rate of copper by fire dilution is not ideal.To cure the above problems we propose a new method.It is appropriate dilution by natural gas-deep reduction copper slag to extract the valuable metals for the smelting of Cu-containing Antibacterial Stainless Steel.Firstly it is an appropriate dilution by the stirring of the natural gas.When the matte is separated from the slag,copper and the other noble metal are recovered.Then we get the secondary slag.After deep reduction of the secondary slag the molten iron includes copper can be got,which can be used to produce Cu-containing Antibacterial Stainless Steel.The stirring with natural gas is the core technology.The thermodynamics of the reaction system between copper slag and natural gas was analyzed in this paper firstly.Then the impact factors of the dilution process were studied.It included reaction temperature,bubbled time of natural gas,settling time,the addition of the additive such as CaO,SiO2,sulfurizing reagent and so on.The composition and mineral phase of copper slag,orthogonal experiment of copper slag reduced by pyrolysis nature gas and 2kg amplification experiments in the medium frequency induction furnace were analyzed.The analysis and characterization of the result was conducted by using XRD,SEM,ICP,chemical analysis and metallographic microscope analysis methods.The following conclusions could be obtained:(1)The thermodynamic calculations shown that in 1200-1300°C,copper slag occurred the reduction reaction of copper,iron oxide and ZnO and MoO,but other oxides such as CaO,SiO2 and Al2O3 could not happen the reduction reaction;Copper oxide(Cu2O,CuO)in slag could happen vulcanization reaction with FeS;Used thermodynamic calculation software such as HSC,FactSage rendering the gas composition of the balance of iron oxide reduction process and predominance diagram of Fe-Cu-C-O-S and Fe-Cu-H-O-S,there was a common area of Cu2S and FeS which existed stably.(2)The dynamics analysis of copper slag,C,and CaO system and copper slag,C system was proceeded.And the reaction activation energy was respectively 535.4KJ/mol and 562.6KJ/mol.The addition of CaO could reduce the initial reaction temperatu re,activation energy and in favour of dilution of copper slag.(3)From the natural gas reduce and dilution copper slag single factor experiment's results,it could be obtained that Reaction temperature was 1250?,the air flow was 80ml/min,outlet pressure was 0.1 MPa,the aeration time was 20min,the settling time was 60min,the optimum addition of CaO was 4%,the rate of Fe/SiO2 was 1.4.And the content of Fe3O4 in the residue was 1.22%.The content of copper in the residue was 0.38%.The recovery rate of copper was 91.57%.Porous spray gun was better than that of single-hole spray gun,bubble ultra-micronization model,the copper slag dilution process.(4)Induction furnace enlargement experiment,the separation result of residue and matte was good.The matte's macrostructure was uniformity.The main basis material was Cu2S.Some part of Cu elemental substance consists in matte.Solid solution Cu3As2 was formed by harmful elements As and Cu.0 was evenly distributed in matte phase;Some part of Zn,Pb,As in the original slag enter into the dust with form of oxide.The main volatile matter was ZnO.The main residue was 2FeO-SiO2.