Comparison of different surface disinfection treatments of drinking water facilities from a corrosion and environmental perspective

Abstract

Surface disinfection of water facilities such as water wells requires measures that can remove pathogens from the walls to ensure a high drinking water quality, but many of these measures might increase corrosion of the contact surfaces (often highly pure steel) and affect the environment negatively due to disinfectant-contaminated waste sludge and wastewater. Today, most treatments worldwide are based on hypochlorites. We investigated the extent of corrosion during treatments of steel at relevant conditions of ozone, sodium, and calcium hypochlorite for drinking water preparation, utilizing weight loss, electrochemical, solution analytical, and surface analytical methods. The ozone treatment caused significantly less corrosion as compared with sodium or calcium hypochlorite with 150-250 mg/L active chlorine. Hypochlorite or other chlorine-containing compounds were trapped in corrosion products after the surface disinfection treatment with hypochlorite, and this risked influencing subsequent corrosion after the surface disinfection treatment. A life cycle impact assessment suggested ozone treatment to have the lowest negative effects on human health, ecosystems, and resources. Calcium hypochlorite showed the highest negative environmental impact due to its production phase. Our study suggests that ozone surface disinfection treatments are preferable as compared with hypochlorite treatments from corrosion, economic, and environmental perspectives.

Microbial and physicochemical assessment of irrigation water treatment methods

“…Addition of calcium or sodium hypochlorite has been shown to increase the pH of water from neutral to 8Á5-9, making it more alkaline (Stewart et al 2001;Romanovski et al 2020). This study utilizes calcium hypochlorite tablets for treatment of irrigation water; however, no significant changes were observed in the pH for the chlorine-based treatments.…”

Life Cycle Assessment and Life Cycle Cost of Sludge Dewatering, Conditioned with Fe2+/H2O2, Fe2+/Ca(ClO)2, Fe2+/Na2S2O8, and Fe3+/CaO Based on Pilot-Scale Study Data

“…For instance, the carbon emissions generated during the production of CaO included the direct carbon dioxide emissions from the decomposition process of limestone in addition to the greenhouse gases generated from energy consumption; On the other hand, it came from the difference in energy structure. As an example, the main energy for the production of calcium hypochlorite by using the sodium method was natural gas, thus reducing the carbon emission of the process . However, the production cost of calcium hypochlorite was increased (discussed in the Life Cycle Cost).…”

“…As an example, the main energy for the production of calcium hypochlorite by using the sodium method was natural gas, thus reducing the carbon emission of the process. 41 However, the production cost of calcium hypochlorite was increased (discussed in the Life Cycle Cost). Furthermore, the sludge conditioning stage was a major contributor to carbon footprint and energy consumption (Figures S4 and S5).…”

In Vitro Antiviral and Virucidal Activity of Ozone against Feline Calicivirus

“…Conversely, chlorination could leave residues toxic to humans and wildlife because its decomposition produces trihalomethanes and other halo-organic carcinogens [ 43 ]. O 3 , unlike sodium and calcium hypochlorite, does not induce corrosion on the steel components of water systems, healthcare facilities, and surfaces where food is processed and handled [ 44 ].…”