Irkutsk Research Institute of Precious and Rare Metals and Diamonds (Irkutsk, Russia):

Emelyanov Yu. E., Leading Researcher, e-mail: emelyaov@irgiredmet.ru
Shketova L. E., Researcher
Gudkov S. S., Head of Laboratory
Kopylova N. V., Researcher

Geochemistry Institute of Siberian Branch of Russian Academy of Sciences (Irkutsk, Russia):

Verkhozina V. A., Leading Researcher

Heap biooxidation tests were carried out for refractory ores of three deposits. It was found that the recovery of gold from refractory ores with the usage of heap biooxidation is similar to conventional processes, such as: flotation, vat biooxidation and cyanidation of biooxidation product.
The recovery of gold from the products of heap biooxidation for deposits No. I, No. II and No. III was 76%, 77% and 80%, respectively.
According to the researches, the heap biooxidation depends sufficiently on the ore drilling grade. The ore decomposes during bioleaching. In this case, this process can replace grinding.
A long process time (about a year) is a feature of heap biooxidation.
This process could be used for carbonate ores only if it is combined with an acid-generating process.

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