Investigation of the suitability of activated and non-activated bentonites from the Imerys Mine (South Africa) for geosynthetic clay liners

Geosynthetic clay liners (GCLs) have become a suitable substitute for compacted used prevention of leachate percolation from landfills and tailings dams into the groundwater system. The characteristics most bentonites is improved through process activation by mixing with soda ash (Na2CO3). This paper presents investigation results suitability Imerys Mine in South Africa use GCLs. Both activated non-activated were investigated X-ray diffraction (XRD) analysis swell index, fluid loss, plate water absorption Atterberg limits tests. XRD indicate that bentonite smectite content 58% 67%, respectively. index was significantly lower than bentonite. samples tested at different times subsequent to revealed minimum 4 weeks time required fully activate it ideal ratio 1:16. loss tests displayed slightly above 18 mL because low tested. capacities 133% 121%, plasticity 101%, 15% higher overall concluded medium-quality borderline properties requires least beneficiation achieve complete suitably be as Significance: significance this geotextile industry. study relevant geotechnical engineers, environmental geologists, engineering geologists other related professionals working geosynthetic whereby key ingredient. provides an optimum sodium carbonate beneficiation. We further recommend quality control measures should implemented ensure bentonite, including blending qualities