Abstract: The invention relates to a method and apparatus for extracting gold from gold ore. The apparatus and process save capital and operating costs in the extracting of gold from gold ore and include comminution and leaching of the ore, and more particularly the apparatus and process reduce the costs for the ore grinding, and make a fine ore grinding superfluous without having to accept a reduction in the gold yield during leaching. The gold ore is subjected to a product bed stressing and interparticle crushing in the nip of a high-pressure roller press before being leached and the product that has been product-bed-comminuted and subjected to interparticle crushing and the product agglomerates thereby formed are piled on a heap that is sprayed with a lixivium.

Abstract: A method and apparatus for continuous pressure comminution of brittle grinding stock such as cement clinker wherein simultaneous operations of unit grain comminution and product bed comminution are carried out in the roller gap of the same roller machine in such a manner that the grinding stock is first precomminuted by means of the unit grain comminution in a wider roller gap and immediately thereafter, the grinding stock fragments produced in the unit grain comminution are further comminuted by the technique of product bed comminution in the region of the narrowest roller gap. The continuous pressure comminution is characterized by a high pressure of more than 2 metric tons per centimeter of roller length, with a sifter being provided after the pressure roller.