Geomembrane Performance Testing-Impacts of a Negative Langelier Saturation Index on Geomembranes

摘要

In 2013, we were informed of a possible failure of a linear low density (LLDPE) liner used in a reverse osmosis potable water treatment application in Australia. Further testing confirmed the material had a premature loss of antioxidants resulting in surface cracking and welding problems. Additional analysis confirmed the fluid had an unusually negative Langelier Saturation Index (LSI) of -3.5. It was determined that a negative 3.5 LSI indicated the water was extremely under saturated with calcium carbonate resulting in a highly corrosive environment to the liner and distribution system. This paper explains the research undertaken to investigate the impacts of a negative LSI and the performance testing completed to determine a suitable replacement geomembrane.