回填材料膨润土阻滞性能优化研究

Study on retardancy optimization of bentonite backfilling material

在膨润土中添加不同比例的石英砂和活性炭,研究它对示踪气体SF6的扩散行为和滞留能力的影响。结果表明:SF6在膨润土中扩散系数随石英砂含量的增加而变大;随活性炭含量的增加而减小。在膨润土中加入活性炭使吸附性能优化,对示踪气体扩散阻滞能力有明显的提高;添加石英砂改善其物理性能,但引起阻滞能力的下降。活性炭和石英砂的最佳配比各为5%。

Effects of volume fractions of activated carbon and silicon dioxide in bentonite on the diffusion coefficient and retardancy (retardant ability) of tracer gas SF6 were studied. The results showed that the diffusion coefficient increases with increasing silicon dioxide, but decreases with increasing activated carbon. Addition of activated carbon to bentonite can enhance its adsorptivity, thus resulting in a better retardancy. On the other hand, addition of silicon dioxide will lead to a reduction of retardancy though some physical characteristics can be improved. The optimum volume fraction of activated carbon and silicon dioxide was 5% each.