Bioleaching Of Yongping Copper Sulfide Ore And Tongling Copper Sulfide Ore By Mixed Bacteria

Bioleaching is an economical method for the recovery of metals from minerals,especially from low grade ores,overburden and waste from current mining operations.Bioleaching of ores has many advantages, such as moderate reaction,low energy consumption,simple technological flowsheet,environment friendly,etc.Compared with leaching of ores using single bacteria,the leaching efficiency of the mixed bacteria is obviously increased.More and more studies focus on bioleaching of ore using mixed bacteria.In the acid mine drainage(AMD),there are many kinds of Autotrophic and Heterotrophic bacterium,which can be used in bioleaching.In this paper,The mixed bacteria selected from the sites of seventeen different acid mines were respectively enriched in 9K medium plus copper Sulfide ore as energy substances.To test its leaching efficiency,bioleaching of copper sulfide ore from Yongping and Tongling are studied in shake flask cultures under conditions of temperature 30℃, initial pH value of 2.0,pulp density 10%,inoculating volume of microorganisms 10%,partile size＜0.075mm and rotating speed of 180rpm.In order to increase Cu leaching rate of Yongping Copper mine and Tongling Copper mine,acclimatized mixed bacteria and ultrasonic wave tratement and Ag⁺ are used in the bioleaching.CGAs was applied to investigate the population dynamics of the best mixed bacteria groups during bioleaching of Yongping Copper sulfide ore and Tongling copper sulfide ore.The Leaching results on an orbital shaker show that the adapted mixed bacteria has a great differernce in leaching efficiency.YS2-2 has the highest Cu leaching rate from Tongling copper sulfide ore in 17groups,68.69%of Cu is leached on the 24^th day.and the adapted mixed bacteria G has the highest Cu leaching rate from Yongping Copper sulfide ore in 17groups,27.12%of Cu is leached on the 16^th day. Ultrasonic wave has the effect of promoting leaching rate.The dissolution rate of Yongping copper sulfide ore and Tongling copper sulfide ore were increased 3%—4%and 3%—8.41%after 24d bioleaching.By adding 10 mg/L silver-containing catalyst at the initial stage of the bioleaching,the dissolution rate of Tongling copper sulfide ore was increased 17.53%-19.63%and the dissolution rate of Yongping copper sulfide ore was increased 32.31%-34.54%after 24 d bioleaching. Yongping copper sulfide ore.Cu of 94.63%is leached from Tongling ore by mixed bacteria group YS2-2,Cu of 70.04%is leached from Yongping ore by mixed bacteria group G,The addition of sliver ions was more beneficial to the improvement of the Yongping ore dissolution rate than that of Tongling copper sulfide ore.The microbial compositions were quit different during bioleaching of Tongling copper sulfide ore and Yongping copper sulfide ore with mixed bacteria G and YS2-2.When bioleaching Tongling copper sulfide ore with YS2-2,A.ferrooxidans,A.thiooxidans,A.caldus,Sulfobacillus sp.,Alicyclobacillus sp.,actinobacterium 8ev,Arthrobacter globiformis,Acidisphaera sp.,Actinomyces naeslundii,Ferromicrobium sp.S-4,Leptospirillum sp.excited in the shaker.A.ferrooxidans,A.thiooxidans andAlicyclobacillus sp.were the dominant bacteria,which is.While in the bio-oxidation process of Yongping copper sulfide ore with YS2-2,only A. thiooxidans was the main microorganism.When bioleaching marmatite, A.ferrooxidans,A.thiooxidans,Alicyclobacillus sp.,Acidisphaera sp.,Arthrobacter globiformis,Sulfobacillus sp.,Leptospirillum sp.t excited in the shaker.The main microorganisms were A.ferrooxidans and Alicyclobacillus sp.and Arthrobacter globiformis.