High-temperature pretreatment by means of an alkaline aqueous solution of ores with a clayey gangue containing at least one upgradable element other than uranium, vanadium and molybdenum.

摘要

Process for high-temperature pretreatment, by means of an aqueous, so-called pretreatment, solution, of ground ores containing at least one upgradable element other than uranium, vanadium and molybdenum, in which the gangue contains clayey compounds capable of forming a plastic suspension which is stable in the presence of water, characterised in that, in order to avoid any preliminary calcination of the ore and to permit easy subsequent separations of the liquid and solid phases, the ore whose particle size does not exceed the mesh for releasing the metal(s) to be upgraded is placed in contact with an alkaline pretreatment solution containing at least 2x10-5 g/l of OH- ions and the mixture formed is then immediately heated to the minimum pretreatment temperature of at least 120 DEG C over a time of not more than 30 minutes counted from placing the ore in contact with the aqueous pretreatment solution.