Effect of Stainless Steel Reconstruction on Microbial Safety of Water Quality in Secondary Water Supply System
The material in secondary water supply system has a significant impact on the supplied water quality.In order to study the effect of stainless steel material renewal on the improvement of microbial water quality in the secondary water supply system,the microbiological quality of drinking water in the Shanghai Direct Drinking Water Demonstration Zone before and after stainless steel materials renovation was evaluated using the heterotrophic bacteria plate count(HPC)detection method based on R2A medium and the microbiome technology based on 16S rRNA gene high-throughput sequencing.The results showed that the renovation of stainless steel pipes can effectively decrease the microbiological number in the secondary water supply system.After the implementation of stainless steel material reconstruction at the secondary water supply system in summer,the quantity of HPC decreased greatly.Among them,the average of the high-rise pump decreased from 968 CFU/mL before the renovation to 178 CFU/mL,a decrease of about 82％.The 6th floor riser had decreased by about 93.7％from an average of 1 383 CFU/mL before the renovation to 88 CFU/mL.The overall level of HPC in unmodified community B was higher than that in modified community A,and the number of HPCs in renovated community B was lower than before the renovation.Temperature could signficantly influence the HPC number in the secondary water supply system.The number in October was higher than that in November and December.From the raw water,treated water to the water inlet of the pump station,the dominant bacteria changed from Acinetobacter to Pseudomonas,and after entering the house.Phreatobacter gradually dominated.Compared with modified community A,community B before reconstruction has higher relative abundance of microorganisms with potential pathogenic phenotype and biofilm forming ability phenotype,and was mainly provided by Acinetobacter with high abundance.The replacement of stainless steel pipes in the community can control some microbial risks in drinking water by reducing the abundance of bacteria related to biofilm formation and pathogenicity.
drinking waterstainless steel pipesheterotrophic bacteria plate count(HPC)high-through put sequencing for microbiomewater quality of pipelines
万方数据
维普
