Evaluation of commercial peroxyacetic acid products for wastewater disinfection -considering feasibility of the on-site generation of peroxyacetic acid

摘要

Municipal wastewater is treated at publicly owned treatment works where it is subjected to physical, chemical, and biological processes for reintroduction to the natural environment. The final step before releasing the water to rivers, lakes, or oceans is "secondary effluent disinfection." Traditionally, chlorine is used as a disinfectant to inactivate harmful bacterial pathogens and viruses. Chlorine is relatively inexpensive, but it takes a toll on the environment through 1) formation, with organic matter, of carcinogenic disinfection byproducts and 2) high toxicity to aquatic organisms in the receiving water. For these reasons, the industry is moving away from chlorination, in favor of ultraviolet light, ozone, and peroxyacetic acid (PAA). This study examines the efficacy of peroxyacetic acid as a regulatory-compliant alternative to chlorine for disinfection. Of particular interest is the on-site generation of PAA at the point of use, to reduce transportation costs, increase shelf life, and optimize dosing. Advanced oxidation processes, in which combinations of disinfectants are believed to exhibit synergistic effects through the formation of highly reactive hydroxyl radicals, are also investigated.