Francis R. Costa, Christophe Salles, Anh Tuan Tran, Jeroen Oderkerk and Thomas Hjertberg
# 2012 Barcelona
Over the years polyethylene has gained preference as the material of choice for water distribution pipes due to its long successful track record offering comparatively lower frequency of leakage, corrosion resistance, flexibility, light weight, easy installation, etc. However, in recent years, there have been growing concerns over the influence of water disinfectants (mainly chlorine, Cl and chlorine dioxide, ClO2) on the life time of polyethylene pipes, especially when operating conditions, like high concentration of disinfectant, highly aggressive disinfectant, high temperature, etc are employed. Industries, research and test institutes are working for thoroughly understanding the topic. Attempts are being made both in developing a comprehensive test method for life time prediction or material evaluation and also in finding superior material solution that can be commercialised. It is now well known how chlorine and chlorine dioxide interact with polyethylene pipe. Though several parameters, such as operating and installation conditions, quality of pipe extrusion, etc can play significant roles, the prerequisite of a good performance is the polyethylene composition that has inherently high resistance against these disinfectants, i.e. against the direct chemical attack caused by them and the processes, like crack formation, crack propagation, etc followed afterwards. In the present paper, we highlight the evolution of polyethylene compounds with time when exposed to such disinfectants, especially how the stabilizing chemicals make a significant difference in overall performance. Keywords : Water disinfectant, chlorine dioxide, chlorine, additive, polyethylene pipe