The transport of Pb(II) or Cd(II) in subsurface has been studied in the literature; however; their co-transport in porous media in presence of colloids has not been clearly understood. In this work, a series of column experiments were conducted to study Pb(II) and Cd(II) co-transport in saturated porous media under various experimental conditions with different combination of colloidal solution (montmorillonite colloid, manual loessial soil colloid and humic acid), flow rate (0.1, 0.5 and 1.0 ml min⁻¹) and sand grain size (0.4–0.8mm and 0.8–2.0mm). The results showed that increase of flow rate and grain size promoted the mobility of Pb(II) and Cd(II), furthermore, the presences of mobile colloids also enhanced the mobility of the two heavy metals, meanwhile, Cd(II) showed higher mobility than Pb(II) in the columns. Findings from this work enhanced current understanding of the competitive transport and colloid-facilitated transport of heavy metals in saturated porous media.

文献中已经研究了Pb（II）或Cd（II）在地下的迁移。然而; 尚不清楚它们在胶体存在下在多孔介质中的共转运。在这项工作中，进行了一系列柱实验，研究了在不同的实验条件下，采用胶体溶液（蒙脱土胶体，黄土土体胶体和腐殖酸的不同组合）在饱和多孔介质中共迁移的Pb（II）和Cd（II） ），流速（0.1、0.5和1.0 ml min ^-1）和沙粒尺寸（0.4-0.8mm和0.8-2.0mm）。结果表明，流速和晶粒尺寸的增加促进了Pb（II）和Cd（II）的迁移率，此外，流动性胶体的存在也增强了两种重金属的迁移率，而Cd（II）的迁移率更高。柱中的迁移率高于Pb（II）。这项工作的发现增强了当前对饱和多孔介质中重金属的竞争性运输和胶体促进运输的理解。