Evaluation of a new milling process for the Caetite-Brazil uranium ore

The Caetite-Brazil uranium facility produces about 400 tonnes/year of U₃O₈ from an ore averaging 0.29% U₃O₈. The steps of the process consist of: ore crushing, heap leaching with sulphuric acid, U separation and purification by solvent extraction with a tertiary amine followed by stripping with a sodium chloride solution and precipitation as ammonium diuranate and then product drying. A change in the milling process is being evaluated in order to increase the production as well as uranium recovery. Heap leaching will be replaced by conventional tank agitated leaching of the -590 μm ground ore slurry in a sulphuric acid medium. The replacement of the stripping reagent is also being considered. (author)