滨海含水介质胶体释放的粒度和动电性质表征

Characteristics of particle size and electrokinetic properties of colloid release in coastal water-bearing media

为了研究滨海地区含水介质胶体在不同水动力条件下的释放规律,在野外调查的基础上,采用室内土柱实验研究不同水力梯度下胶体释放的动态特征,同时表征了释放胶体的粒径分布、ζ电位和电泳淌度。结果表明:随着水力梯度的增大,释放胶体浓度逐渐增大,到水力梯度为10时突增达到峰值,随后浓度逐渐降低,变化幅度小;胶体累积释放量随着孔隙体积数的增大呈线性增长,不同水力梯度下增长幅度不同;在低水力梯度下粒径小的胶体优先释放出来,胶体的ζ电位、电泳淌度大多数为正,而在高水力梯度下粒径大的颗粒也会释放出来,胶体的ζ电位、电泳淌度大多数为负。

In order to investigate the release law of colloid in coastal water-bearing media under different hydrodynamic conditions, on the basis of field investigation, column experiments were conducted to study the characteristics of colloid release under different hydrodynamic gradients. Moreover, the particle size distribution, ξ potential and electrophoretic mobility of released colloid were discussed. The results show that the concentration of colloid release increased gradually with the increase of hydraulic gradients, and reached a maximum at a hydraulic gradient of 10. Then the concentration decreased gradually with little range of variation. The cumulative capability of colloid release increased linearly with the increase of pore volume number, and the extent of increase was different at different hydraulic gradients. The small size of the colloid particle, for which the ξ potential and electrophoretic mobility were mostly positive, was released preferentially at the low hydraulic gradients, while the large size of colloid particles was also released at high hydraulic gradients when the ξ potential and electrophoretic mobility were negative.