Electrochemical oxidation for stormwater disinfection: How does real stormwater chemistry impact on pathogen removal and disinfection by-products level?. (December 2018)

• Record Type: Journal Article
• Authors: Feng, Wenjun; McCarthy, David T.; Henry, Rebekah; Zhang, Xiwang; Zhang, Kefeng; Deletic, Ana
• Is Part Of: Chemosphere. Volume 213(2018)
• Page Start: 226
• Page End: 234
• Publication Date: 2018-12
• Subjects: Stormwater harvesting -- Boron doped diamond (BDD) anode -- Enterococci -- Campylobacter -- C. perfringens -- Disinfection by-products (DBPs); Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2018.09.038
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Preliminary laboratory work has shown that electrochemical oxidation (ECO) is a promising technology for disinfection of harvested stormwater. This paper focuses on understanding how stormwater chemistry ( e.g. pH, chloride, bicarbonate, ammonia and total organic carbon - that can vary substantially between sites) impacts the disinfection performance of ECO. Real stormwater samples from four different urban catchments were collected and tested for ECO performance in disinfecting stormwater pathogens using a boron doped diamond anode under the current density of 4.2 mA/cm 2 . Results showed that total disinfection of indigenous Escherichia coli (E. coli), as well as three different stormwater pathogens ( Enterococci, Campylobacter and C. perfringens ) was achievable for all four tested stormwater within 30 min. Compared to the synthetic stormwater, lower disinfection rates were observed in real stormwater which has more complex chemistry. Stormwater chloride concentration was the only tested parameter that had significant impact on the treatment performance, with higher initial stormwater chloride concentration leading to an increased disinfection rate. Disinfection by-products in the treated stormwater were well below the Australian Drinking Water Guideline value for health, with its production level positively correlated to the pH values of stormwater. Highlights: It is the first comprehensive study of ECO for real stormwater disinfection. Complex chemistry in real stormwater did slow down the disinfection rate. Chloride level was the only factor that have significant impact on the disinfection. Production of DPBs from ECO was below drinking standard hence not of concern. ECO is able to disinfect pathogens in real stormwater within 30 min.