Material processing apparatus

A materials processing apparatus for the wet attrition of particulate material, the apparatus comprising:

• an attrition scrubber comprising at least one mixing chamber having at least one pair of opposing impeller blades or paddles arranged to direct material in opposing directions to facilitate attrition of the material within the mixing chamber, and a drive device for driving the impeller blades or paddles;
• a dewatering screen comprising a deck having a plurality of openings therein for passing water and undersize material therethrough into a sump beneath the deck, a vibration generator for imparting vibration to the deck, and the dewatering screen being mounted upstream of the attrition scrubber whereby oversize material from a downstream end of the deck of the dewatering screen passes into the mixing chamber;
• and
• a hydrocyclone comprising a cylindrical body having an inlet for supplying a feed slurry into the hydrocyclone tangentially, and a conical base, outlets being provided at upper and lower ends of the hydrocyclone, whereby an underflow, containing a coarser fraction of the feed slurry, passes out of the lower outlet while an overflow, containing a finer fraction of the feed slurry and most of the water, passes out of the outlet at the upper end of the hydrocyclone, a pump being provided for pumping material from the sump of the dewatering screen to the inlet of the hydrocyclone, wherein the underflow from the hydrocyclone is passed into the mixing chamber of the attrition scrubber and 15 wherein at least a portion of the overflow from the hydrocyclone is passed into the sump of the dewatering screen to maintain a predetermined level within the sump.