Pilot scale bioleaching of copper sulphide flotation concentrate using different consortium of mesophile, moderate and extreme thermophile microorganisms
This technical contribution aimed at extracting copper from a flotation concentrate comprising copper sulphides such as chalcopyrite ( CuFeS2) , at a content of nearly 70％ , and bornite ( Cu5FeS4 ) as 30％ , amounting a copper content of 28. 8％. The pilot column was loaded with around 1 ton of a mix of a support rock coated with flotation concentrate in a ratio of 9 ? 1, respectively ( 890 kg of support rock to 96. 2 kg of flotation concentrate). The support rock used was a copper primary ore in particle size ranging from 6 mm to 1. 25 mm. The coating operation was done pouring the flotation concentrate slurry, with 70％ of solids, on top of the support rock on a rotating mixer. The aqueous phase of the slurry was a mix of sulphuric acid solution, at a pH 1.5, with the mesophile, moderate and extreme thermophile microorganisms at 106cells per gram of flotation concentrate. During the leaching process a period of 7 days were used to make the mesophile microorganisms from acting at 30X1, where the copper concentration in solution started levelling out. At that time the temperature was raised gradually up to 50t , where the moderate thermophile microorganisms reach their optimum temperature, remaining there for 14 days levelling out the copper concentration as such. Finally, the temperature was raised up to 66t , which is the extreme thermophile temperature, remaining at that value for 83 days. Therefore, the copper extraction reached, considering the contribution of the three consortium used, was of 90. 6％ , which was really high bearing in mind the considerable chalcopyrite content of that concentrate. We are expecting to enhance such extraction with optimization of the experimental parameters.
bioleaching flotation concentrate autotrophic microorganisms copper sulphide
Luis Sobral Carlos Souza Debora Oliveira
Centre for Mineral Tecnology Avenida Pedro Calmon, 900, Rio de Janeiro, Brazil
国际会议
The 19th International Biohydrometallurgy Symposium(第19届国际生物湿法冶金大会 IBS2011)
长沙
英文
731-735
2011-09-18（万方平台首次上网日期，不代表论文的发表时间）