Research On The Bacteria Of Water Quality And Pipeline Biofilm In Water Supply Network

The water supply network was an important part in the whole water supply systems, and carries drinking water that humans depended on. It played a key role in protecting security of water supply. Through the monitoring of water quality in the network and the research on the pipeline biofilm, the paper gave the analysis of factors that endangered the water quality in drinking water system, which provided technical support for guarantee the security of water supply.Firstly, the simulative distribution network in the lab and the pipeline network were chosen for the sampling and the monitoring. Research and analysis were also carried on the regularity for the change of the conventional indicators, the indicators that affected the heterotrophic plate counts (HPC) and the biological stabilization in drinking water. It came to the conclusion by the analysis of the experimental data that conventional indicators had close relationship with the regrowth of bacteria. For that reason, it was important to control the turbidity, the residual chlorine and other factors. The indicator that indicated the content of the organic matters in drinking water were also studied. It showed from the studies of AOC, BDOC that the content of organic matters was higher than the standard, and the water was biological unstable, which had potentially danger on the security of water supply.Secondly, the paper discussed the research on pipeline biofilm in the simulative distribution network using molecular biological technologies. The 16SrDNA sequence of E. coli and the Pseudomonas were chosen to be amplified. The result showed the existence of E. coli both in samples of the biofilm and samples of the drinking water. Compared to the monitoring of the bacteria using the conventional methods, the test based on PCR amplification were more sensitive and reliable. Besides, there were no signals showing the existence in both samples, which mean the drinking water was regularly safe.A real-time quantitative PCR method was innovational used in the study of bacteria in drinking water. The method was used to study the E. coli in pipeline biofilm. And a real-time quantitative PCR method based on SYBR Green I to study the E. coli was established, which represents the whole new way on the research of bacteria in water distribution system was found. The content of E. coli in total bacteria was detected by analyzing the biofilm sample and the water sample. Lastly, the paper discussed the factors that affect the growth of bacteria in water supply network. On this basis, effective measures about how to reduce the microbiology risk and improve the water quality of the distribution network were brought forward.