The effectiveness of chlorine residuals in inactivation of bacteria and viruses introduced by post-treatment contamination
| Autor: | Kazuyoshi Kawata, M.C. Snead, Vincent P. Olivieri, Cornelius W. Krusé |
|---|---|
| Rok vydání: | 1980 |
| Předmět: |
Environmental Engineering
business.industry Chemistry Ecological Modeling Microorganism Sewage chemistry.chemical_element Contamination Pollution Tap water Environmental chemistry polycyclic compounds Chlorine Shigella sonnei IMViC Bacterial virus business Waste Management and Disposal Water Science and Technology Civil and Structural Engineering |
| Zdroj: | Water Research. 14:403-408 |
| ISSN: | 0043-1354 |
| DOI: | 10.1016/0043-1354(80)90203-1 |
| Popis: | The protection afforded the water consumer by the maintenance of a free or combined chlorine residual in water distribution systems was evaluated in a laboratory system provided with a simulated cross connection. Tap water, adjusted to the appropriate pH, temperature and chlorine residual, was challenged with varying levels of autoclaved sewage seeded with Shigella sonnei, Salmonella typhimurium, a coliform (IMVIC++−−), poliovirus 1 and f2 bacterial virus. Comparative survivals of these microorganisms were evaluated over 2 h periods. As expected, microbial inactivation was increased by lower pH, higher temperature, higher initial chlorine concentration and lower sewage concentration. An initial free chlorine residual was more effective than an equivalent initial combined chlorine residual. Generally, S. sonnei, S. typhimurium and the coliform organism were inactivated at the same rate but poliovirus 1 was more resistant and f2 was the most resistant. At pH 8, with an initial free chlorine residual of 0.7 mg 1−1, and added sewage levels of up to 1% by vol, 3 logs or greater bacterial inactivation was obtained within 60 min. Viral inactivation under these conditions was less than 2 logs. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|