Tian Yimei

Research of enhanced coagulation as the pretreatment of membrane process in a reclaimed water plant

In order to enhance the coagulation pretreatment of a reclaimed water plant, an experiment was employed by means of the Polymerization Aluminum Chloride (PAC), the Polyferric Sulfate (PFS) and the Ferric Trichloride (FeCl3). The performances of Powder Active Carbon (PAC) and Pre-coagulation Chlorine Addition using as coagulant aids were also discussed. The results showed, turbidity removal could reach 87.5% by using PACl as coagulant, optimum dosage should be 12~ 16mg/L; Compound of PSF and PACl had better performance than Compound of FeCl3 and PACl; PAC and Pre-coagulation Chlorine Addition could enhance the effect of coagulation process.

Prediction Model of Iron Release When the Desalinated Water into Water Distribution System

A trial network was constructed in the laboratory to simulate the water quality condition of real water distribution network. Three models were established based on experimental data and regression analysis method, which are total regression model, stepwise regression model and principal component regression model. The relationship between iron concentration and related water quality indexes was described quantitatively and the iron concentration was predicted by the reliable statistical models. The result shows as for prediction accuracies of these models, the principal component regression model is a little better than total regression model, and is much better than stepwise regression model. The accuracies of three models are 72.03%, 65.02% and 72.92% respectively.

Constructing the water circulation system to maintain and improve the urban landscape water

In this article, artificial wetland and landscape river were used to build the water circulation system to maintain and improve the quality of urban landscape water and to prevent water eutrophication. According to the Liebig law of the minimum, it could be determined that TP played an important role in the process of eutrophication and TP (total phosphorus) was the primary constraint condition to control eutrophication. After the water circulation system operated, the TP content of the landscape river water was detected. The result showed that the TP content became stable. Compared the water quality of landscape river with the stagnant waters, through the 6 times samplings, the content of TP, ammonia nitrogen in the landscape river was lower than the stagnant waters. Through the assay of TP content and the contrastive experimentes, the role of the water circulation system was proved.

Study of iron release kinetics model when desalinated water transmitted in water distribution system

Desalinated water, which could destroy the original balance of pipe networks and water when transmitted in water distribution system, would result in the substandard effluent in pipe ends such as high turbidity, chromaticity or iron content caused by iron release. In this paper, a trial network was constructed in the laboratory to simulate the water quality condition of real water distribution system. A kinetics model based on iron release mechanism was established using the experimental data. On the whole, the prediction accuracy of this kinetics model is over 80%, and it can be used on iron release prediction. Especially, the longer the immersion time is, the better it works.