低掺量木质素磺酸钙改良红黏土氡气阻滞效果

为使覆盖后的铀尾矿库滩面长期稳定可靠，以我国南方湿润区某铀尾矿库为研究对象，采用自制模拟滩面覆土层氡析出试验装置，通过开展吸附试验验证木质素磺酸钙（木钙）吸附氡气性能；开展低掺量木钙改良红黏土对铀尾矿的覆盖控氡试验，研究其作为覆土层对铀尾矿库滩面的氡气阻滞效果，以及改良红黏土的强度特性。结果表明：木钙对氡具有较明显的吸附性能，6%及8%掺量木钙改良红黏土的降氡率较素红黏土分别高9%和12%；木钙改良红黏土的强度在0~6%掺量内增强，在6%~8%略微减少，但整体而言强度均有所提升。

Effect of Low Content Calcium Lignosulfonate Stabilized Red Clay on Radon Retardation

In order to achieve long-term stability and reliability of the covered uranium mill tailings(UMTs) pond beach face, simulation studies were carried out applying a self-made experimental instrument of radon exhalation for soil overburden on the beach, aiming at a UMTs pond in humid location of southern China, to verify radon adsorption performance of calcium lignosulfonate(CaLS) through adsorption experiments. Experiments on enhanced radon retarding performance of CaLS-stabilized red clay were carried out. Effect of CaLS-stabilized red clay as soil overburden for radon retardation on the beach surface of the UMTs pond was studied, and the strength characteristics of CaLS-stabilized red clay was studied. The results show that CaLS has some radon adsorption properties. The radon retardation rate of 6 mass percent and 8 mass percent CaLS content is 9 percent and 12 percent respectively higher than that of red clay cover without CaLS. The strength of CaLS-stabilized red clay is enhanced within 0-6 mass percent content and slightly reduced between 6-8 mass percent, but the strength of soil is enhanced overall by the effect of CaLS.