Research On High-efficiency Microbial Disposal Technology Of Copper Smelting Fume

Copper smelting fume contains a large amount of heavy metal elements,which is both a potential resource and a huge environmental risk.Based on the basic physical and chemical properties of copper smelting fume,this paper studies the effect of acidihiobacillus ferrooxidans and sulfate-reducing bacteria on heavy metals in copper smelting fume.At the same time,the effect of microorganisms on the migration and transformation behavior of heavy metals in smelting fume was also preliminarily explored under the synergy of additives.Taking copper smelting fume as the research object,the heavy metals in smelting fume were extracted by means of digestion and Tessier five-step extraction method,what's more,the mineral phase,element composition,heavy metal content,occurrence state,bioavailability and chemical leaching of copper smelting fume were explored.So it can identify typical heavy metals in them.The results show that the copper smelting fume is mainly spherical granular dust.The main metal elements are Pb,Bi,Zn,As,Cd,Sn,Cu and Fe,which mass ratio decreases in turn.It's mineral phases are mainly Pb SO₄,Pb S,Cd S,Zn O.Among them,Cd,Cu,and Zn are mainly in the exchangeable state,which are metals with high mobility and bioavailability.As,Bi,Sn,Fe are mainly in the residual state and Pb is mainly in the sulfide state along with the bound state,which belong to the metal with less mobility and bioavailability.The leaching rate of each metal element in acid environment is significantly higher than that in the neutral or alkaline environment.The Cd,Cu and Zn are easily leached under the condition of p H=2.0,on the contrary,other metal elements are relatively leaching difficultly.Through the analysis of the action characteristics of acidihiobacillus ferrooxidans on heavy metals in smelting fume,it was found that At.f could grow stably at the 1%copper smelting fume.In the liquid phase,the p H increased from 1.8 to 2.1 and then decreased to 1.7.The Eh rise from 320m V to 630m V.The At.f has a great contribution to the dissolution of As,an inhibitory effect for Pb and Bi and little effect for other heavy metal elements.For the phases,it concentrates in lead sulfate and jarosite.Under the synergy of the three additives,the liquid concentration of Cd and Zn,which are more easily leached out,has no great effect;travertine cooperates with At.f to adsorb As,Cu,Pb and Bi;bentonite cooperates with At.f showed adsorption of As,Cu,Pb and Bi,and the liquid concentration of Cu changed little;zeolite cooperates with At.f to promote the release of As,which has little effect on Pb,Cu and Bi.The dissolution of other metals has a certain inhibitory effect.Through the analysis of the action characteristics caused by sulfate reducing bacteria for heavy metals in the smelting fume.The SRB can resist less than 0.1%copper smelting fume.The p H increases from 6.6 to 7.5.Moreover,the Eh first drops to-210 m V and then increased to 50 m V.The concentration of each heavy metals is at a low level in the first 5 days and increases slightly in 6?7 days with the action of SRB.There is the adsorption and mineralization of Zn,Cd,Pb and Cu in particular.For the phases,it mainly includes lead sulfate,zinc sulfide,lead sulfide and cadmium sulfide.The three additives can reduce the survival pressure of SRB to a certain extent,which leads concentrations of Cu,Bi,Cd,and Zn are finally maintained at a low level.The effect on As and Pb could be enhanced by the synergistic action of travertine,bentonite and zeolite with SRB,respectively.