水泥固化体的铯的浸出行为

通过对硅酸盐水泥、碱矿渣水泥以及掺加沸石的碱矿渣水泥固化体在２５℃和７０℃下Ｃｓ￣＋的浸出行为研究发现，掺加３０％沸石的碱矿渣水泥固化体２８天Ｃｓ￣＋累积浸出量仅是硅酸盐水泥固化体的１／１０，是碱矿渣水泥固化体的１／６－１／４。几种水泥固化体Ｃｓ￣＋的累积浸出分数Ｐｔ与ｔ￣（１／２）作图都呈折线关系，前３天Ｃｓ￣＋扩散系数大于后期。Ｃｓ￣＋的浸出主要取决于水泥固化体的结构致密程度和固化体连通孔溶液中游离Ｃｓ￣＋浓度，而后者则又与水化产物束缚Ｃｓ￣＋的能力成反比和水化产物的溶解度成正比。因此碱矿渣水泥固化Ｃｓ￣＋的能力大于硅酸盐水泥。同时探讨了水泥固化体Ｃｓ￣＋的浸出模型。

THE Cs LEACH BEHAVIOUR OF CEMENT WASTE FORM

t was investigated that the Cs leach behaviour of three kinds of cement waste froms, Port-land Cement(PC),Alkali-Activated Slag Cement( AASC)and Alkali-Activated Slag Cementwith Zeolite(AASC with Zeolite), at 293 and 343K. The results show that 28 days cumulativepercent leach of Cs from AASC with Zeolite waste from is one-tenth that from PC waste formand one-sixth to one-fourth that from AASC waste form.The broken line graphes exist be-tween Pt(cumulative leach fraction ) and t(1/2)(square root of time)for these cement waste forms.The diffusion coefficients of Cs calculated form slopes before 3 days are larger than those after 3days for all waste forins. The Cs leachability mainly depends on the compact degree of cementwaste form and concentration of free Cs in the interconnected pores of cement waste form,andthe latter is in inverse proportion to the ability of retarding Cs by hydrates and in proportion to thesolubilities of hydrates.So,the ability of immobilizing Cs in AASC waste form is larger than thatin PC waste form. The leach model of Cs from cement waste from is described.