Abstract: Uranium and boron are abundant in uranium-bearing paigeite ore in Wengquangou area,Liaoning Province, which mainly exist in the form of uraninite and ascharite. The grades of U and B2O3 in the tailings of uranium-bearing paigeite ore in a concentrator are 0. 013 3% and 14. 05%. In order to improve the utilization rate of uranium and boron resources in the tailings of iron separation,through the automatic mineral identification and characterization system (AMICS) test,chemical analysis,balance calculation of uranium and boron elements and particle size analysis,the characteristics of mineral existence, particle size distribution,dissociation characteristics and element distribution in the tailings were carried out. According to the tailings properties,the separation process of " gravity-flotation combination" of " enhanced physical field preconcentration of fine uranium and boron minerals,shaking table separation,gravity tailings flotation" was formulated. The test results indicate that:by optimizing centrifugal separation,shaking table separation and flotation,the separation indexes of U grade of 0. 151 8% and U operation recovery rate of 60. 16% in uranium concentrate and B2O3 grade of 14. 76% and B2O3 operation recovery rate of 94. 84% in boron concentrate were obtained. Uranium minerals are mainly distributed in -74 μm fine grains with a U distribution rate of 77. 13%,while boron minerals are mainly distributed in - 38 μm fine grains with a B2O3 distribution rate of 84. 67%. Compared with the original process index,the recovery rates of U and B2O3 in iron tailings are improved,which can increase the benefit of enterprises. The " gravity-flotation combined process" of uranium-bearing paigeite ore iron separation tailings can effectively recover fine uranium and boron minerals,which has reference significance for the recovery of other fine minerals.

Key words: uranium-bearing paigeite,Knelson centrifugal beneficiation,flotation,gravity-flotation combined process,resource recovery