Review of the Anti-Pollution Performance of Triple-Layer GM/GCL/AL Composite Liners

Abstract

Landfill leachates contain several types of pollutants and complex components, which pollute soils and groundwater. To compensate for the limitations of single-layer and double-layer liners, a triple-layer liner system composed of a geomembrane (GM), geosynthetic clay liner (GCL), and attenuation layer (AL) was invented and widely used in landfill anti-pollution systems. In this paper, the available literature on triple-layer GM/GCL/AL composite liners is summarized. First, the four main transport processes of pollutants through the composite liner, including convection, diffusion, adsorption, and degradation, were analyzed, and the anti-pollution performances were evaluated. According to this, the pollutant transport model considering the transport activity and transport state was classified, and the solution methods were summarized. Finally, the breakthrough time expressions of the composite liners were determined, which provided a base for evaluating their long-term performance and predicting the service life. The purpose of this literature review is to scientifically evaluate the anti-pollution performance of GM/GCL/AL and provide a scientific base and theoretical guidance for extending its application.

Effects of Temperature, Ionic Strength and Humic Acid on the Transport of Graphene Oxide Nanoparticles in Geosynthetic Clay Liner

“…The geosynthetic clay liner (GCL) is one of the most important barriers preventing the leakage of pollutants in landfills [32][33][34]. Previous studies have shown that the GCL can reduce the ground subsidence caused by garbage leakage, improve the stability of landfills and prolong the service life of landfills [35,36]. One of the main components of the GCL is bentonite particles, and the adsorption of bentonite particles is pretty large, resulting in the fact that the retention mechanism of the GCL is quite different from traditional porous media [37].…”