Flow and Transport through Clay Membrane Barriers

摘要

The flux equations for liquid and solute migration through clay membrane barriers (CMBs) used in waste containment and remediation applications are discussed. A simplified analysis of flow through a geosynthetic clay liner (GCL) using measured values for the chemico-osmotic efficiency coefficient (ω) of the GCL shows that membrane behavior can result in a total liquid flux that counters the outward Darcy flux due to chemico-osmotic counter flow. Also, the effect of a CMB is shown to reduce the contaminant mass flux through the barrier relative to the contaminant mass flux that would occur in the absence of membrane behavior due to two mechanisms: chemico-osmotic counter flow, and contaminant (solute) restriction. An important consideration with respect to solute restriction is the implicit correlation between co and the effective diffusion coefficient, D~* , of the contaminant.