Chemical sulfatization of chrome-containing sludges from DUBERSAY tailing dump

Waste chromium production sludge from the Dubersay tailings dump is present in huge quantities with a magnesium oxide content of up to 40 %. The chrome-containing waste was sintered at 1 100 °C, the resulting sinter was mixed with sulphuric acid when heated to 300 °C. The resulting mixture after heating was leached with water at 90 °C, the solid precipitate was washed and dried to yield a chrome concentrate containing 55,4 % Cr2O3, 8,2 % SiO2. Evaporation of the purified solution produces magnesium sulphate which is a magnesium fertilizer

Intensification of copper leaching from heaps using biological oxidation

The article presents the results of experiments intended to leach copper from ore heaps of complex mineral composition biochemically. The processing of such heaps is complicated due to the presence of oxidized copper minerals among significant fragments of sulfide minerals and iron-calcium silicates. This factor does not allow to perform standard sulfuric acid leaching effectively without the use of additional oxidation catalysts, or to apply beneficiation methods for that kind of raw materials. Use of A. Ferrooxidans bacteria adapted to the composition of the copper dump, as a bio-catalytic agent, significantly accelerates the leaching process and increases the copper recovery degree into the productive solution

Intensification of copper leaching from heaps using biological oxidation

The article presents the results of experiments intended to leach copper from ore heaps of complex mineral composition biochemically. The processing of such heaps is complicated due to the presence of oxidized copper minerals among significant fragments of sulfide minerals and iron-calcium silicates. This factor does not allow to perform standard sulfuric acid leaching effectively without the use of additional oxidation catalysts, or to apply beneficiation methods for that kind of raw materials. Use of A. Ferrooxidans bacteria adapted to the composition of the copper dump, as a bio-catalytic agent, significantly accelerates the leaching process and increases the copper recovery degree into the productive solution

Chemical sulfatization of chrome-containing sludges from DUBERSAY tailing dump

Waste chromium production sludge from the Dubersay tailings dump is present in huge quantities with a magnesium oxide content of up to 40 %. The chrome-containing waste was sintered at 1 100 °C, the resulting sinter was mixed with sulphuric acid when heated to 300 °C. The resulting mixture after heating was leached with water at 90 °C, the solid precipitate was washed and dried to yield a chrome concentrate containing 55,4 % Cr2O3, 8,2 % SiO2. Evaporation of the purified solution produces magnesium sulphate which is a magnesium fertilizer