Tracer Study For Leachant Leakage From Stope Leaching Uranium

Stope leaching of uranium, a new mining technology of mining and smelting, it can obtain better economic benefits in recovery of low grade uranium ore, but it also brings a lot of potential environmental hazard, especially the potential impact on the groundwater. A suitable tracer need to be found for the tracer study in the process of heap and spraying in order to find the leachant leakage from stope leaching of uranium timely and accurately.In this study, fluorescein sodium was chosen out from three candidate tracer(such as fluorescein sodium, Bromide ion and Iodide ion) by static experiment for its little adsorption by uranium ore and influence on uranium leaching. Moreover, surfactant MES, MAEPK, DMSS and SDS were studied, finding that surfactant SDS can improve the leaching rate of uranium and lower adsorption of fluorescein sodium by ore. The further research on tracer properties about fluorescein sodium and SDS were conducted by column experiment.The static experiment results show that three kinds of tracers nearly had no effect on the uranium leaching rate; sodium fluorescein had the minimum distribution coefficient in the ore, it shows that the ore only had little adsorption of sodium fluorescein; surfactant SDS strengthened uranium ore leaching, surface tension of lechant was reduced by 52.94%. The lechant had the lowest surface tension and the uranium leaching rate reached to the highest when the concentration of surfactant SDS was 0.008mol/L. So the tracer of fluorescein sodium and 0.008mol/L surfactant SDS were selected for column experiment.The column experiment results show that fluorescein sodium had no influence on uranium leaching and the uranium leaching rate increased nearly 9.01% by surfactant added in leachant. Meanwhile, surfactant reduced the adsorption of fluorescein sodium, especially reduces the initial adsorption greatly, which made the concentration of fluorescein sodium in the first through-fall increase 20.8 times. The distribution coefficient(Kd) of fluorescein sodium were 6.66ml/g and 4.22ml/g by using surfactant SDS or not, and the retardation factor(Rd)were 29.46, 20.59, which reduces 36.63% and 30.11% respectively.Therefore, surfactant SDS and fluorescein sodium can monitoring to determine the leakage in stope leaching of uranium timely and accurately, which can avoid leakage and wasting of uranium resources. It has great significance and research value in the stope leaching of uranium.