Research And Modeling The Microbiology Water Quality Of Drinking Water In Distribution Networks

Now, more attention is put on the research of water quality of the water treatmentplant outlet, and the regard to water quality of distribution network is not enough. Thedistribution network is an important part in the whole water supply systems, and itplays a key role in protecting security of water supply. Researches were made toexplore the variation rules of water quality in distribution network, especially thewater quality of microbiology, and study the factors affect the water quality. The workapplies technique support for guarantee water supply secure.Firstly, an experimental investigation (about one year) is presented on evaluatingthe water quality of the selected residual area, there are 20 parameters analyzed. Agreat deal of water quality data was got. (1) The variation rules of regular parametersand the correlation between every parameter were analyzed, the water qualitysituation of high-rise building water tank was also evaluated. The results showed thatmost parameters over standard serious, especially after the change of water source.There are well correlations between some parameters, and the water quality controlmust involve every parameter and control them synthetically. (2) Trichloromethane(TCM) was detected. The pollution of disinfection by products, and the factors thatinfect the yield of TCM were evaluated. (3) Dense water sampling was made to studythe variation and decay process of chlorine and turbidity in 24h. (4) Cultureconditions that affecting the result of heterotrophic plate counts (HPC) were studied,and the parameters correlated with HPC were analyzed. The biological stabilizationwas researched.Secondly, molecular biological technologies were innovational used in the studyof bacteria diversity in drinking water. Five specific bands were got, sequenced andindexed, Phylogenetic tree was mad by DNASTAR, and represented bacteria wereanalyzed, most of them were got by methods without culture. Four GenBankaccession numbers were got. It's proved that molecular biological technologies couldbe used in the research of bacteria diversity in drinking water, it is useful to protectthe security of microbiology water quality, and helpful for ensure the health of people.Lastly, HPC prediction model were developed by SAS and Matlab software withthe methods of multi-linearity regression, Logistic stepwise regression, principalLogistic stepwise regression and artificial neural network (ANN). HPC predicted asqualification and disqualification. The result showed that the prediction effect of ANNmodel is better than others, and the precision is good. Model also developed by ANNfor simulating the correlation between parameters and HPC, and the modeling resultis good, limit value of some parameters are provided.