ALTA 2013: Autoclave technology of refractory gold-bearing pyrrhotite concentrates and residues of bioleaching

ALTA 2013 4th Anuual Gold Event, Melbourne (Australia), 2013
J.M. Shneerson, M.T. Zhunusov, L.V. Chugaev, A. Markelov, S. Drozdov

Bacterial leaching is widely used by gold companies as a method of processing of refractory gold concentrates. At present this method is used by more than 10 companies worldwide. In this paper, two variants of the possible upgrade of the existing technology of processing refractory sulfide concentrates are considered. Laboratory tests were conducted on the autoclave oxidation of bioleaching products and flotation concentrate. A mathematical model of the continuous process was generated based on this data, parameters for pilot testing were calculated and preliminary calculation for the industrial process was made.

As a result of the pilot test it was shown that the additional autoclave oxidation of bioleaching products can significantly improve gold recovery to 96% and reduce cyanide consumption from 50 kg/t to 6.4 kg/t. It was shown that the optimal parameters of POX for bioleaching products are temperature 225°C and oxygen partial pressure 5-7 bar. The data obtained will be used for technical and economic evaluation, which will select the optimal scheme for the modernization of the technology for processing refractory gold concentrates