Rule of oxygen transmission in dump leaching

Abstract

According to the chemical equations, the flux and concentration of oxygen required during bacterial leaching sulfuric mineral were investigated; the rule of air bubble transmitted in granular was researched in the Dump Leaching Plant of Dexing Copper Mine. The results show that lack of oxygen in dump leaching is the critical factor of restricting leaching reaction. Pyrite is the primary oxygen-consuming mineral in bioleaching. When its content is too high, it needs a great deal of oxygen for reaction and competes for the finite oxygen with objective minerals, and thus the leaching velocity decreases greatly. The average size of ore particles and diameter of bubbles are the key parameters affecting the mass transfer coefficient. Reverse analysis was adopted, and it shows that 44.8 m³ air per unit ore can meet the requirement of production if the molar ratio of pyrite to chalcopyrite is 10.

Keywords

dump leaching / bioleaching / oxygen transmission / pyrite / mass transfer coefficient

References

[1] BrierleyC L. Bacterial succession in bioheap leaching [J]. Hydrometallurgy, 2001, 59(2): 249-255

[2] IsamuS. Microbial leaching of metals from sulfide minerals[J]. Biotechnology Advance, 2001, 19(2): 119-132

[3] KrebsW, BrombecherC, BosshardP P, et al.. Microbial recovery of metals from solid[J]. FEMs Microbiology Review, 1997, 20: 650-617

[4] JeffreyM I, BreuerP L, ChuC K. The important of controlling oxygen addition during the thiosulfate leaching of gold ores[J]. International Journal of Mining Processing, 2003, 72(1): 323-330

[5] HeathA R, RumballJ A. Optimising cyanide: oxygen ratios in gold CIP/CIL circuits[J]. Minerals Engineering, 1998, 11(11): 999-1010

[6] KondasP D, GriffithW F, JaraJ O. The use of oxygen in gold cyanidation [J]. Canadian Metallurgical Quarterly, 1996, 35(1): 39-45

[7] LiuJian-she, XiaHai-bo, WangZhao-hui. The investigation into inefficient leaching in Dexing Copper Leaching Plant [J]. Copper Engineering, 2004, 20(1): 23-26(in Chinese)

[8] LiWei-zhong, PengXiao-hua. The optimization study and practice on dump leaching method in Dexing Copper Mine[J]. Hydrometallurgy of China, 1999, 9(3): 29-33(in Chinese)

[9] ZaKe-bing. The analysis and discussion on affecting factor of dump leaching production in Dexing Copper Mine[J]. Mining Technology, 2003, 3(9): 4-7(in Chinese)

[10] WangHong-jiang, WuAi-xiang, LiQing-song. Several key questions settled urgently on leaching technology in large copper mine dump pit[J]. Mining and Metallurgical Engineering, 2004, 19(2): 15-19(in Chinese)

[11] WeiDe-zhouResource microorganism technology [M], 1996, Beijing, Metallurgical Industry Press(in Chinese)

[12] ZhangJian-guo, WangHai-feng, JiangYan. Introduction to the development of alkaline in-situ leaching of Uranium in America[J]. Uranium Mining and Metallurgy, 2005, 24(1): 6-8(in Chinese)

[13] PrevenslikT V. The cavitation induced becquerel effect and the hot spot theory of sonoluminescence [J]. Ultrasonics, 2003, 41(4): 313-317

[14] BartleetR WSolution Mining: Leaching and fluid recovery of materials[M], 1998, New York, Gordon and Breach Science Press

[15] SherwoodT K, PigfordR L, WilkeC RMass transfer[M], 1988, Beijing, Chemical Industry Press(in Chinese)

[16] ChenLin. Feasibility study on full capacity realization of leaching plant[J]. Copper Engineering, 2002, 18(4): 41-44(in Chinese)