非平衡吸附对核素迁移的影响及平衡速率参数的确定

Influence on radionuclide migration by nonequilibrium sorption and identification of rate coefficient

放射性核素以水为载体在多孔介质中迁移时，吸附和解吸作用不容忽视吸附和解吸是一非平衡过程．非平衡状态下吸附和解吸达到平衡的快慢程度可以用平衡速率参数ａ来表征本文首次定量分析了非平衡吸附对核素迁移的影响，提出基于室内分配系数实验求取ａ值的方法，并将室内实验得出的ａ值同原位核素迁移试验拟合值进行比较；结果表明用此方法求出的ａ值可作为非平衡吸附核素迁移数学模型的主要参数依据。

When radionuclides migrate in porous medium with water serving as carrier the mechanism of sorption and desorption is not negligible. Sorption and desorption is a nonequilibrium process represented by the rate coefficient a which shows how quickly the nonequilibrium condition in sorption and desorption reaches equilibrium. In this paper, the quantitative analysis was made for the first bine that the influence of nonequilibrium on the ingration of radionuclides and the method for identification of rate coemcient a was presented basing on the indoor test for the distribution coefficient The result of this method was compared with that of the in-situ radionuclides migration test, which shows the value of a from this method can be used as preliminary parameter for numerical model of radionuclide migration in porous medium with nonequilibrium sorption.