Chemical aspects of peracetic acid based wastewater disinfection

Abstract

Peracetic acid (PAA) has been studied for wastewater disinfection applications for some 30 years and has been shown to be an effective disinfectant against many indicator microbes, including bacteria, viruses, and protozoa. One of the key advan tages compared to, e.g., chlorine is the lack of harmful disinfection by-products. In this paper a pilot-scale study of PAAbased disinfection is presented. Indicator microbes ( E. coli, total coliforms and coliphage viruses) as well as chemical param eters (pH, oxidation-reduction potential (ORP), chemical and biochemical oxygen demand (COD and BOD), and residual PAA and hydrogen peroxide) were studied. The main aim of this investigation was to study how these selected chemical parameters change during PAA treatment. Based on the results, disinfection was efficient at C∙t values of 15 to 30 (mg∙min)/ℓ which equals to a PAA dose of 1.5 to 2 mg/ℓ and a contact time of 10 to 15 min. In this concentration area changes in pH, COD and BOD were negligible.

Authors

Categories