You are here:
A Pilot Study of On-site Generated Peracetic Acid and its Application for Municipal Wastewater Disinfection
Citation:
Namboodiri, V., D. Murray, A. Garg, R. HAUGHT, F. Alvarez, AND C. Cypcar. A Pilot Study of On-site Generated Peracetic Acid and its Application for Municipal Wastewater Disinfection. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-20/152, 2020.
Impact/Purpose:
One of the major strategies of the NPDES permit and Clean Water Act (CWA) in making “reasonable further progress toward the national goal of eliminating the discharge of all pollutants” is to require effluent limitations based on the capabilities of the technologies available to control those discharges. This study is designed to contribute towards above strategies for improving secondary effluent treatment efficiency, energy conservation and effluent quality. Recently, peracetic acid (PAA) is emerging as an alternative to chlorination in many utilities in US. PAA is getting more acceptance due to its potential to reduce known health and ecological impacts raised from continued usage of chlorination or other treatment methods. However, application of PAA is limited in waters with high oxidant demand and for certain microbial species that require high dose concentrations. By combining PAA with UV technologies will help to overcome the issues where one or both fails independently. UV treatment prevents normal reproduction of microbial community but insufficient UV treatment results in cell repair and become viable again. PAA disrupts the chemiosmotic function of the lipoprotein cytoplasmic membrane and transport due to cell wall rupture. The cell repair issues are significantly low in PAA-UV combination treatment compared to UV alone treatment. Our recent studies revealed that PAA and UV combination can exceed the performance than that of each individual technology. Economic savings can be achieved due to the reduction in UV capital expense, power usage, operational expense, maintenance, easy installation of PAA/low capital need. In addition, PAA can be used to support aging UV systems around nation without much capital expense. This approach will also help to achieve new regulatory changes or needs without increasing UV capital expense or energy footprint.
Description:
For the past several years, the Office of Research and Development (ORD) and the Metropolitan Sewer District of Greater Cincinnati (MSDGC) have been investigating the use of peracetic acid (PAA) as an alternative to chlorination and several aspects of its implementation in the real world. We have studied the treatment of secondary effluent with PAA alone and in combination with UV with an objective to increase the efficiency and reduce the cost of disinfection treatment. This study report on the development and evaluation of on-site generated PAA for wastewater disinfection is a collaborative research effort of ORD, ORD’s industrial CRADA partner Lubrizol and MSDGC. This report summarizes the results from a pilot study that we conducted recently at the EPA’s T&E Facility. In this study, we treated secondary effluent from the MSDGC’s Mill Creek facility with on-site generated PAA and then compared disinfection efficiency and the rate of microbial inactivation with commercially available PAA and chlorine. It is observed that the onsite generated PAA has comparable disinfection and microbial inactivation properties compared to PAA from other sources.