Affiliation:
1. School of Chemical Engineering, College of Engineering, Seoul National University, Shilim-dong, Gwanak-gu, Seoul 151-742
2. Water Microbiology Division, National Institute of Environmental Research, Kyungseo-Dong, Seo-Ku, Inchon 404-170, Korea
Abstract
ABSTRACT
Ozone is widely used to disinfect drinking water and wastewater due to its strong biocidal oxidizing properties. Recently, it was reported that hydroxyl radicals (
·
OH), resulting from ozone decomposition, play a significant role in microbial inactivation when
Bacillus subtilis
endospores were used as the test microorganisms in pH controlled distilled water. However, it is not yet known how natural organic matter (NOM), which is ubiquitous in sources of drinking water, affects this process of disinfection by ozone-initiated radical reactions. Two types of water matrix were considered for this study. One is water containing humic acid, which is commercially available. The other is water from the Han River. This study reported that hydroxyl radicals, initiated by the ozone chain reaction, were significantly effective at
B. subtilis
endospore inactivation in water containing NOM, as well as in pH-controlled distilled water. The type of NOM and the pH have a considerable effect on the percentage of disinfection by hydroxyl radicals, which ranged from 20 to 50%. In addition, the theoretical
C̅T
value of hydroxyl radicals for 2-log
B. subtilis
removal was estimated to be about 2.4 × 10
4
times smaller than that of ozone, assuming that there is no synergistic activity between ozone and hydroxyl radicals.
Publisher
American Society for Microbiology
Subject
Ecology,Applied Microbiology and Biotechnology,Food Science,Biotechnology
Reference26 articles.
1. Bancroft, K., P. Chrostowski, R. L. Wright, and I. H. Suffet. 1984. Ozonation and oxidation competition values: relationship to disinfection and microorganisms regrowth. Water Res.4:473-478.
2. Cho, M., H. Chung, and J. Yoon. 2002. Effect of pH and importance of ozone initiated radical reactions in inactivating Bacillus subtilis spore. Ozone Sci. Eng.24:145-150.
3. Dahi, E. 1976. Physicochemical aspects of disinfection of water by means of ultrasound and ozone. Water Res.10:677-684.
4. Elovitz, M. S., U. von Gunten, and H. P. Kaiser. 2000. Hydroxyl radical/ozone ratios during ozonation processes. II. The effect of temperature, pH, alkalinity, and DOM properties. Ozone Sci. Eng.22:123-150.
5. Facile, N., B. Barbeau, M. Prevost, and B. Koudjonou. 2000. Evaluating bacterial aerobic spores as a surrogate for Giardia and Cryptosporidium inactivation by ozone. Water Res.34:3238-3246.
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