Particle characteristics influencing the UV disinfection of drinking water

摘要

This study investigated the influence of virus-particle association on UVrndisinfection. Specifically, the objectives of the study were to determine whether colloidalrnparticles could protect viruses from UV light and to determine which particlerncharacteristics enhance protection. Three types of particles (kaolin clay, humic acid, andrnactivated sludge particles), two coagulants (alum and ferric chloride), two viral surrogatesrn(MS2 coliphage and bacteriophage T4), two filtration conditions (no filtration or 0.5-rnmicron filtration), and two UV doses were considered in a series of jar tests designed asrnfactorial experiments to evaluate the effect of particle characteristics (size, composition)rnon UV disinfection of particle-associated viruses. The results suggest that particulaternorganic content is a critical parameter in the protection of waterborne viruses from UVrndisinfection. The findings reinforce the importance of a multi-barrier approach tornpathogen control that includes the effective physical removal of particles and particleassociatedrnpathogens prior to disinfection.