Optimal Of Booster Chlorination And The Implementation Of Algorithms To It In Water Distribution Network

Chlorine disinfection is an widely used antisepsis technology in most of our water purification plants. Proper quantity of chlorine adding to the water supply network plays a key role to the water quality. But majority water plants cast chlorine once only at the outlet of the treatment plants, which is often not sufficient to reach a good spread-out of chlorine in the system because the chlorine residual decreases with the residence time, and also may results in high chlorine concentration in some local districts and an increase in disinfection by-products dangerous to people's health. To achieve this specific goal, an idea of optimization of booster chlorination was put forward in this paper. That was to locate some rechlorination sites in the network so that the applied disinfection dose was sufficient to meet the inherent demand in the treated water to provide sufficient protection against microbial infection, and at the same time assure more uniform disinfectant residual and minimize the production of DBPs.The mechanism of chlorine disinfection and the factors that influence the chlorine residual decay in the network were studied first in the paper. By analyzing legion chlorine residual decay models, an applied first-order decay model was selected. Then the indirect optimal model of booster chlorination was set up on the basis of hydraulic models and the former chlorine residual decay model. The first optimal model was to ascertain the locatin and the number of rechlorination stations, which was solved by using genetic algorithms and MATLAB. The second optimal model was to find the best chlorine injection pattern, which was solved by using Lingo software.In order to validate the validity of the above models and algorithms, they were used on an existing network given in the EPANET software and a practical network of Daqing City. Firstly, use EPANET 2.0 to calculate the hydraulic models. Secondly, optimize the booster chlorination based on the hydraulic solution. The optimal results indicate that booster disinfection can make the residual concentrations of the control points meet the standards while helping to reduce variability in nodal concentrations compared to conventional disinfection only at the source. They also show that booster chlorination can assure less risk...