Leakage Control And Energy Consumption Optimization In The Water Distribution Network Based On Joint Scheduling Of Pumps And Valves

With the increasing scale of urban water supply networks,leakage control and energy consumption management have gradually become the most concerning issues and challenges for water treatment plants(WTPs)in addition to water quality.The joint scheduling of pumps and pressure reducing valves(PRVs)in the water distribution network can reduce excessive pressure and distribute pressure more evenly,which achieves comprehensive reduction of leakages and energy consumption.Considering that the traditional manual empirical scheduling method has many shortcomings,based on computer technology,network modeling theory,and optimization scheduling theory,it is of great significance to establish an optimization scheduling model to jointly schedule the distribution networks to obtain greater comprehensive benefits,which will also lay an important foundation for the WTPs to realize the scientific modern management.Taking into account the main shortcomings of the existing research and methods,in order to make the optimization scheduling model more adaptable and generalizable,this paper has taken the PRV(position and opening settings)and the working status of pumps(switch or pump speed)as decision variables and the cost savings contributed by leakage reduction and energy consumption savings as the objective function.A genetic algorithm(GA)is used to optimize the solution under multiple working conditions,which maximized the economic benefits brought by PRV and/or pump scheduling.Based on a small distribution network and the urban distribution network of H city in southern China,the performance of three control strategies(PRV-only scheduling,pump-only scheduling,and joint scheduling of PRVs and pumps)are compared to each other.In the small network,joint scheduling has achieved the best economic benefits in reducing the gross cost contributed by leakage and energy consumption of the three control strategies,which results in a leakage reduction of 33.4%,an energy consumption reduction of 25.4%,and a total cost reduction of 33.1%,when compared to the original status.Compared with the pump-only scheduling,the total cost is reduced by 9.9%;in the network of H city,the joint scheduling reduces the leakage of original network by 15.0%,the energy consumption by 16.2%,the total cost by 15.1%in three periods,and the total cost has been decreased by 5.4%compared with the pump-only strategy,which has a significant effect.On the basis of the optimal scheduling scheme of the urban network of H City(determination of the position of PRVs),the further optimization scheduling was performed for other periods except the three periods selected by the model.Taking periods 6 and 18 as examples,the joint scheduling reduced the total cost of period 6 by 6.3%and the total cost of period 18 by 17.2%compared with the original status,which proves the effectiveness and adaptability of the scheduling model;when the minimum pressure limit of some nodes is raised from 18m to 22m,taking periods 8 and 18 as examples,through comparing the result before and after scheduling when with or without local pressure limit,it can be found that joint scheduling can better respond to the pressure limit.The addition of PRV makes the dispose of pressure limit more flexible.