You are here:
Dual Disinfection of Wastewater Effluent with Peracetic Acid and Sodium Hypochlorite in a Sequential Treatment
Citation:
Garg, A., S. Islam, M. Nemade, B. Murugesan, V. Namboodiri, A. Ouermi, AND B. Smith. Dual Disinfection of Wastewater Effluent with Peracetic Acid and Sodium Hypochlorite in a Sequential Treatment. In Proceedings, 92nd Water Environment Federation Technical Exhibition and Conference (WEFTEC 2019), Chicago, IL, September 21 - 25, 2019. WEF, Alexandria, VA, 1735, (2019).
Impact/Purpose:
Peracetic acid(PAA) is an attractive alternative to chlorination can alleviate certain permit concerns such as high levels of DBPs, effluent toxicity, high total dissolved salts and quenching agent needs. Many utilities in US are currently interested in PAA treatment to reduce/eliminate the use of chlorination/ultraviolet (UV) and also to improve treatment efficiency. Combining PAA and chlorination disinfection approaches (Dual-disinfection) take advantages of each technologies such as cost reduction, improved treatment efficiency, elimination of post chlorine quenching treatment and less permit violations. This practical treatment approach may find application in future municipal wastewater treatment in all over US.
Description:
The Mill Creek Treatment Plant (MCTP) is one of seven wastewater treatment plants operated by the Metropolitan Sewer District of Greater Cincinnati (MSD). On average, MCTP treats about 100 million gallons of wastewater per day (MGD). The treated effluent is discharged into the Ohio River. While renewing MCTP's National Pollutant Discharge Elimination System (NPDES) permit in 2018, The Ohio Environmental Protection Agency (Ohio EPA) included E. coli monitoring and effluent limits for the disinfected effluent during summer months (1 May to 31 October). The weekly and monthly geometric average limits of E. coli were set at 240 colony forming units (CFUs)/100 ml and 126 CFU/100 ml of wastewater respectively. For winter season (1 November to 31 March) the plant continues to use fecal coliform as the primary organism for compliance. This is a change from the previous NPDES permit where fecal coliform was the sole microorganism to measure disinfection efficiency throughout the year.
