Effects of disinfection by chlorine and chlorine dioxide on pipeline biofilm in hot water supply system

被引:0
|
作者
Chai S. [1 ]
Li X. [1 ]
Yang Y. [1 ]
Liu Y. [1 ,2 ]
Zhao L. [2 ]
机构
[1] College of Architecture and Civil Engineering, Beijing University of Technology, Beijing
[2] China Architecture Design & Research Group, Beijing
关键词
Biofilm; Chlorine; Chlorine dioxide; Domestic hot water; Shock disinfection;
D O I
10.11918/j.issn.0367-6234.201711051
中图分类号
学科分类号
摘要
Effective disinfection measures are in urgent need due to the serious biosafety issues in domestic hot water supply system. In this study, biofilms annular reactor was applied to simulate the domestic hot water pipeline system. The effects of chlorine and chlorine dioxide on microbial inactivation in biofilm were investigated. The changes of microbial community and the surface structure of biofilm were further explored using Illumina MiSeq sequencing and scanning electron microscopy (SEM). The results show that by increasing disinfectant concentration, the microbial inactivation rate could be notably improved while the inactivation effect remained stable. 1.5 mg/L chlorine or chlorine dioxide did not achieve a good microbial inactivation effect. However, the complete inactivation of Escherichia coli, total number of bacteria and heterotrophic bacteria (HPC) were observed in the presence of 3-5 mg/L chlorine and chlorine dioxide. 3-5 mg/L chlorine and chlorine dioxide can effectively control the biofilm of hot water pipeline. The results suggest that adequate concentration of disinfectant and disinfection time are important for keeping high inactivation effect. The pipeline biofilm was high in bio-diversity. Different from those in municipal water supply system and the secondary water supply system, the predominant phyla of pipeline biofilm were Deinococcus-Thermus and Proteobacteria, as well as some detected pathogenic bacteria. The shock disinfection of chlorine or chlorine dioxide showed a different inactivation effect on each phylum. Specifically, compared with chlorine, chlorine dioxide had a better inactivation effect on pathogenic bacteria, Proteobacteria, and Chlamydiae. The results of SEM indicate that the surface structure of biofilm was effectively destroyed by chlorine and chlorine dioxide, resulting in the larger gaps, shrinkage, and shedding of biofilm. Moreover, the effect of chlorine dioxide on biofilm surface structure was higher than chlorine. Overall, the results are important for the biosafety in hot water system. © 2019, Editorial Board of Journal of Harbin Institute of Technology. All right reserved.
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页码:51 / 57
页数:6
相关论文
共 17 条
  • [1] Xu P., Long Y., Wu J., Et al., Study on the microbiology of water quality of living hot water, Water & Wastewater, 34, (2008)
  • [2] Proctor C.R., Dai D., Edwards M.A., Et al., Interactive effects of temperature, organic carbon, and pipe material on microbiota composition and Legionella pneumophila in hot water plumbing systems, Microbiome, 5, 1, (2017)
  • [3] Shen C., Research on silver ion disinfection technology of living hot water, (2013)
  • [4] Mathys W., Stanke J., Harmuth M., Et al., Occurrence of Legionella in hot water systems of single-family residences in suburbs of two German cities with special reference to solar and district heating, Int J Hyg Environ Health, 211, 1-2, (2008)
  • [5] Zhao L., Liu Z., Fu W., Et al., Probe into water quality problems in hot water supply system, Water & Wastewater Engineering, 37, 7, (2011)
  • [6] Qian C., Zhao R., Liu Y., Study on Legionella pneumophila contamination of hot system at hotels in Beijing from 2006 to 2010, The 2nd General Meeting and Academic Exchange Meeting of China Architecture Society Building Water Supply and Drainage Research Branch, (2010)
  • [7] Li Y., Research on the safety and disinfection of hot water in building, (2016)
  • [8] Shang S., Research on microbial inactivation of living hot water disinfection technology, (2017)
  • [9] Wang S., Yang Y., Li X., Et al., Effect of shock chlorine and chloramine disinfection on biofilm disinfection in pipe system of secondary water supply, Journal of Harbin Institute of Technology, 49, 8, (2017)
  • [10] Lu W., Wang Y., Zhang X., Biofilm separation and biomass quantification method in biological annular reactor, China Water & Wastewater, 21, 2, (2005)