Extraction processing of concentrated solutions of uranyl nitrate with high impurities content

Process flowsheet of recycling uranium concentrated solutions with its purification from insoluble impurities of iron, silicon, molybdenum, calcium oxides and hydroxides and soluble impurities with application of centrifugal extractors cascade has been developed and suggested for commercial introduction. The process was carried out at extractant saturation (30 % tributyl phosphate in hydrocarbon diluent) in extraction assembly lower than a limiting level (85...95 g/l) and in wash assembly - at limiting saturation (up to 120 g/l). As a result the waste uranium content in water-tail solutions 0,01...0,04 g/l and minimal content of impurities in re-extractors is provide

The research of uranium monoxide-oxide dissolution process in nitric acid

The kinetics of concentrates of uranium monoxide-oxide dissolution process by nitric acid solutions of 5...9 mole/l in the range of 11...90 °C has been studied. It is stated that initial nitric acid concentration increasing results in some uranium dissolution degree increasing only at the first process stage. Temperature increasing significantly raises uranium dissolution degree at the first stage as well. Uranium dissolution degree increases for all studied temperatures with increasing of the process period. The main feature of the studied process is that while dissolving uranium monoxide-oxide the behavior of iron, molybdenum, silicon additives is adequate to that of uranium. The equation of the reducing sphere describes the uranium leaching process from its nitric acid concentrate

Perspectives of Siberian chemical plant in increasing volumes of uranium concentrates recycling

The purification technology of uranium concentrate of natural isotopic composition developed at Siberian chemical enterprise is basically universal, allows recycling uranium concentrates with different content of impurities and obtaining uranium nitrate solutions corresponding by quality to the international standards requirements to uranium hexafluoride preparation for isotopes ASTM C 787-03 separation and to ceramic fuel ASTM C 788-02 preparation. Uranium reserves in Russia and abroad were appraise

Intensifying separating processes of high-concentration uranyl solutions and fine-dispersed suspended solids

The investigations on intensifying separation processes of highly concentrated uranylnitrate solutions and solid fine-dispersed suspended particles (ferric, silicon, molybdenum oxides and others) applying organic coagulants and flocculants have been carried out. It is shown that in the investigated regions of uranium concentrates of 300...450 g/l, nitric acid of 0,5...3,0 mole/l at optimal temperature 30...50 °С for effective phases separation the introduction of 100...200 mg/l of coagulant FLOQULATTM FL 45 С (or an analogue VPK-402) and 5...10 mg/l of flocculant FLOPAMTM FO 4140 PWG type is enoug

Physico-mathematical model of uranium concentrate extraction processing in countercurrent columns cascade

Mathematical model of extraction recycling uranium concentrate in cascade of countercurrent column cascade has been presented. The model describes nonequilibrium interconnected physical-chemical processes subject to a large number of components (uranium, nitric acid, iron, silicon, molybdenum, calcium etc.). On the basis of numerical implementation of mathematical model the software was developed and program-technical complex for increasing the efficiency and optimization of operating the extractive columns cascade and achieving the required technological parameters of the output solutions under changing characteristics of the initial solution was develope