| Summary: | 碩士 === 國立中正大學 === 地震研究所暨應用地球物理研究所 === 94 === Wastewater reclaiming and recycling is quite important , because of the shortage of water resource and reservoir of resuming in environmental consciousness in recent years. If harmful substance or the pathogenic microorganisms public existed in the reclaimed wastewater, it may cause great injury to people's health and environment. Whether harmful substances and pathogenic microorganisms in the wastewater can be dealt with and disinfected by the wastewater treatment plant, it is quite important for reclaiming and recycling wastewater.
This research analyzed 41 wastewater samples of 17 wastewater treatment plants in Taiwan by polymerase chain reaction (PCR). Twenty five wastewater samples (61%) of 10 wastewater treatment plants (58.8%) are detected positive for Legionella by PCR and DNA sequencing, including six kinds of different Legionella spp. - Uncultured Legionella spp., Legionella pneumophila str. Paris, Legionella lytica, Legionella pneumophila serogroup 6, Legionella anisa and Legionella donaldsonii. highly infectious Legionella pneumophila were detected in 2 wastewater treatment plants. The Legionella in the detected raw wastewater are ranged from 6.0 × 104 CFU/L to 1.9 × 105 CFU/L by MPN-PCR estimation. All of 14 air samples collected from wastewater treatment plants were not detected Legionella. Legionella in some wastewater treatment plants are effectively controlled by cleaned treatment procedures or adding HOCl to the discharged wastewater. Ultraviolet (UV) Light is an effective method. It achieved more than 90% deactivations of Legionella while exposing at 2.2 mWs/cm2. The Protease disinfection made Legionella achieved more than 90% deactivations while CT values more then 330000 mg/L•min. It is also effective that Legionella disinfected by HOCl. The HOCl disinfection made Legionella achieved more than 90% deactivations while CT values more then 98 mg/L•min.
Legionella was widely detected in wastewater so that it is very important to control the Legionella in wastewater, in order to reduce the infection risk of people in wastewater and reclaimed wastewater.
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