Study of leaching characteristics on low grade uranium ore of bagjata mine

Abstract

Indian uranium deposits are of low grade and medium tonnage. This necessitates optimal exploitation of all known uranium reserves of the country maximizing the recovery through cost effective and proven process technology. Bagjata uranium deposit in south eastern part of Singhbhum shear zone has been developed recently by Uranium Corporation of India Ltd and the ore is being processed in the existing plant of UCIL at Jaduguda. Extensive laboratory scale leaching tests of ore from Bagjata deposit were carried out to optimize various process parameters for maximizing the recovery of uranium. All tests were conducted in acid medium as the host rock is siliceous in nature. Leaching parameters like temperature, grind size, pulp density, lixiviants, oxidants, etc were varied keeping retention time of 12 hours and maintaining the potential of the leach slurry in the range of –480 to –510 mV. The maximum extraction of uranium (96–97%) was found after 10 hours of leaching using lixiviant sulphuric acid, maintained at pH 1.7–1.8 and pulp density of 60% solid at 60°C in the presence of Pyrolusite (MnO2) as oxidant. The present paper provides a detailed account of optimization of various process parameters. The findings have been successfully implemented in the plant operations achieving desired results.