Leaching behaviour and mechanism of U, Ra and Pb from uranium tailings at different pH conditions.

A large number of radionuclides remain in uranium tailings, and U, Ra and Pb leach out with water chemistry, causing potential radioactive contamination to the surrounding environment. In this paper, uranium tailings from a uranium tailings pond in southern China were collected at different depths by means of borehole sampling, mixed and homogenised, and analysed for mineral and chemical composition, microscopic morphology, U, Ra and Pb fugacity, static leaching and dynamic leaching of U, Ra and Pb in uranium tailings at different pH conditions. The variation of U, Ra and Pb concentrations in the leachate under different pH conditions with time was obtained, and the leaching mechanism was analysed.