Apparatus for biological processing of metal containing ores

A reactor vessel for use in processing metal-bearing solids through bioleaching, said vessel comprising:

• a tank having a bottom and upright walls mounted on said bottom, said tank being dimensioned to contain a liquid suspension of sulfide containing, metal-bearing solids, water, a quantity of thiobacillus bacteria capable of oxidizing said sulfides, carbon dioxide, oxygen and nutrients for said bacteria;
• a drive shaft mounted vertically upright and rotatably within said tank;
• a plurality of arms on said drive shaft extending radially therefrom, said arms being positioned above said tank bottom;
• at least one uprightly oriented planar faced diffuser mounted on at least one of said arms;
• an oxygen-containing gas delivery conduit means mounted within said tank, said conduit means adapted to receive oxygen-containing gas from a source exterior of said tank and convey said oxygen-containing gas to each of said diffusers;
• each of said diffusers including a porous, vertically mounted membrane having a planar face, each of said membranes being adapted to receive a supply of oxygen gas and disperse said gas into said slurry in the form of fine bubbles across said planar face of said membrane;
• and a drive means made mechanically cooperative with said drive shaft wherein said drive means effects a rotation of said drive shaft, said arms and said diffusers about an upright longitudinal axis of said tank;
• a separation means mounted on said tank for removing a quantity of said liquid suspension from said tank, and separating from said quantity of suspension any metal solids from the class consisting of oxidized metal solids and partially oxidized metal solids, said separation means being adapted to convey said oxidized and partially oxidized metal solids to a second reactor system while returning a remainder of said quantity of suspension to said tank.

A reactor vessel for use in processing metal-bearing solids through use of a bioleaching process, said vessel comprising:

• a tank having a bottom and upright walls mounted on said bottom, said tank being configured to contain a metal-bearing concentrate slurry;
• an oxygen supply means mounted within said tank for supplying oxygen to said slurry, said supply means comprising:
• a drive shaft mounted upright within said tank, said drive shaft being rotatable about a vertical, upright axis;
• a plurality of arms mounted radially on said drive shaft, said arms being located above said tank bottom wherein a rotation of said drive shaft effects a rotation of said arms about said vertical axis, said arms being made slidable along the length of said drive shaft and said arms being fitted with lifting means adapted to raise said arms above a surface level of said slurry within said tank wherein said arms are made accessible for maintenance;
• a plurality of uprightly oriented planar faced diffusers positioned on each of said arms, each of said diffusers having a porous planar face membrane configured to receive a supply of oxygen containing gas and to produce gas bubbles in clear water having mean diameters of at most approximately two millimeters;
• said planar face of each of said diffusers being oriented to confront a flow of slurry induced by a rotation of said diffusers about said upright axis, wherein said flow of slurry passes over an entire surface of said diffuser membrane to break up gas bubbles emerging from said membrane face and scour said membrane face to maintain said pores of said membrane free from obstruction;
• and
• a conduit means mounted within said tank for receiving oxygen-carrying gas from a source exterior to said tank and conveying said gas to gas to said diffusers;
• a cooling means mounted within said tank adapted to absorb heat produced within said container means and transfer said heat away from said container means;
• a filtering means mounted in said tank adapted to remove suspended solids-free liquor from said slurry;
• and convey said liquor to disposal exterior of said tank;
• and
• a removal means mounted within said tank adapted to remove a quantity of slurry from said tank, said removal means operating to separate any oxidized and partially oxidized metal solids from said quantity of slurry, said removal means being adapted to then convey said oxidized and partially oxidized metal solids to a second reactor system, and recycle said quantity of slurry, which includes those metal solids which are as yet unoxidized, to said tank.