A METHOD OF RECOVERING PRECIOUS METAL VALUES FROM A PRECIOUS METAL BEARING REFRACTORY SULPHIDE ORE USING A NONSTIRRED SURFACE BIOREACTOR

摘要

A method of biotreating a solid material to remove an undesired compound using a nonstirred surface bioreactor is provided. According to the method, the surface of a plurality of coarse substrates is coated with a solid material to be biotreated to form a plurality of coated coarse substrates. The coarse substrates have a particle size greater than about 0.3 cm and the solid material to be biotreated has a particle size less than about 250 mu m. A nonstirred surface reactor is then formed by stacking the plurality of coated coarse substrates into a heap or placing the plurality of coated substrates into a tank so that the void volume of the reactor is greater than or equal to about 25 %. The reactor is inoculated with a microorganism capable of degrading the undesired compound in the solid material, and the solid material is then biotreated in the surface bioreactor until the undesired compound in the solid material is degraded to a desired concentration. The process is useful for bioremediation of contamined soils, the desulfurization of coal and the biooxidation of refractory sulfide ores and concentrates.