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This paper presents the process flow sheet of the main nuclear industrial units in Brazil and dis-cusses some solvent extraction technical support required for these plants. The Center for the Development of Nuclear Technology—CDTN has been investigating alternative ways to supply the nuclear industry in or-der to improve the industrial processes. Some case study examples are presented, Emulsion from Uranium Solvent Extraction Plant and Itataia Uranium Developments. In Caitité industrial plant the water recirculation has caused continuous changes in the composition of pregnant liquor mainly in the sulfate and chloride concentrations. After some water recirculation cycles, a decrease in the uranium extraction efficiency was noted which was followed by the formation of stable emulsion at the uranium extraction stage. Itataia Ura-nium Developments were performed in a pilot plant for Itataia ore. This ore has the uranium mineral associ-ated to the phosphate. The process consists of four main steps: 1) phosphate concentration, 2) chemical digestion of the concentrate to produce phosphoric acid with dissolved uranium, 3) uranium recovery, and 4) phosphoric acid purification by solvent extraction.
This paper presents the process flow sheet of the main nuclear industrial units in Brazil and dis-cusses some solvent extraction technical support required for these plants. The Center for the Development of Nuclear Technology-CDTN has been investigating alternative ways to supply the nuclear industry in Some-case studies are presented in Emulsion from Uranium Solvent Extraction Plant and Itataia Uranium Developments. In Caitité industrial plant the water recirculation has caused continuous changes in the composition of pregnant liquor mainly in the sulfate and chloride After some water recirculation cycles, a decrease in the uranium extraction efficiency was noted which was followed by the formation of stable emulsion at the uranium extraction stage. Itataia Ura-nium Developments were performed in a pilot plant for Itataia ore. This ore has the uranium mineral associ-ated to the phosphate. The process consists of four main steps: 1) phosphate concentration, 2) chemical digestion of the concentrate to produce phosphoric acid with dissolved uranium, 3) uranium recovery, and 4) phosphoric acid purification by solvent extraction.