137Cs transport in crushed granitic rock: The effect of bentonite colloids
137Cs transport in crushed granitic rock: The effect of bentonite colloids
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DOI：
10.1016/j.apgeochem.2018.06.005
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发表时间：
2018-09-01
影响因子：
3.4
通讯作者：
Hanusova, Irena
中科院分区：
文献类型：
--
作者：
Koloma, Katerina;Cervinka, Radek;Hanusova, Irena
本文着重研究了在连续输入液相的动态柱排列中，在膨润土胶体存在下，铯通过破碎花岗岩的迁移。实验的目的是研究膨润土胶体的存在对花岗岩中铯的行为的影响。示踪剂的行为进行了研究，在有氧条件下应用恒定的示踪剂浓度（活性）和恒定的流速。在色谱柱出口处定期对规定体积的液相进行取样，以测量示踪剂浓度（活性）。通过穿透曲线描述了运输。逐步方法包括以下步骤：1）使用非吸附示踪剂H-3来评估柱的流体力学性能; 2）用去离子水中的膨润土胶体进行柱实验; 3）Cs-137在两个液相（去离子和合成花岗岩水）中的迁移; 4）研究放射性胶体悬浮液在去离子水中的传输。结果表明，花岗岩柱中膨润土胶体与铯的行为完全不同，胶体颗粒对铯在花岗岩上的吸附有影响。膨润土胶体表现为保守的非吸附示踪剂，而相反，铯强烈吸附在花岗岩材料。据确定，铯在花岗岩岩石中的行为是受强烈的吸附铯相对于膨润土胶体。一小部分铯不可逆地吸附在膨润土胶体上，并立即与膨润土胶体一起穿过花岗岩，大部分铯从膨润土胶体上解吸并保留在花岗岩中。
The paper focuses on the study of caesium transport through crushed granite in the presence of bentonite colloids in a dynamic column arrangement with the continuous input of the liquid phase. The aim of the experiments was to investigate the effect of the presence of bentonite colloids on the behaviour of caesium in granitic rock. The behaviour of the tracer was studied under aerobic conditions applying a constant tracer concentration (activity) and constant flow rate. Defined volumes of the liquid phase were sampled periodically at the outlet of the column for the measurement of tracer concentrations (activity). Transport was described by means of breakthrough curves. The stepwise approach included the following steps: 1) the non sorbing tracer H-3 was used to evaluate the hydrodynamic properties of the column; 2) the conducing of a column experiment with bentonite colloids in deionised water; 3) the migration of Cs-137 in two liquid phases (deionised and synthetic granitic water); 4) the study of the transport of the radiocolloid suspension in deionised water. The results revealed the completely different behaviour of the bentonite colloids and the caesium in the granitic column and the effect of colloid particles on caesium sorption on granite. The bentonite colloids behaved as conservative non-sorbing tracers whereas, conversely, caesium sorbed strongly on the granitic material. It was determined that the behaviour of the caesium in the granitic rock was influenced by the strong sorption of caesium with respect to the bentonite colloids. A minor part of the caesium irreversibly sorbed on the bentonite colloids and passed through the granite immediately together with the bentonite colloids, and a major part of the caesium was desorbed from the bentonite colloids and was retained in the granite.