Study On Optimal Dispatching Operation Of Drainage Pumping Station In A Southern City

In decades,the eutrophication degree of Taihu is serious.Some studies have shown that the inflow of river pollutants is the main cause of Taihu Lake pollution,and 45% of the river inflow of Taihu Lake comes from the city.Therefore,the strict restriction of the sewage discharge from the rivers and lakes in the city has a positive impact on the control of the water pollution in Taihu.In recent years,the city on Taihu Lake has largely invested in the construction of urban drainage system,improved the collection rate of urban sewage and improved implementation standards of water treatment,but there are still problems in scheduling and management of the urban drainage system.To improve the operation of urban drainage system,a optimal control is implemented on the basis of the SCADA system.Considering problems occurring in the urban drainage system,following 3 optimization strategies are implemented by modifying PLC programs in pumping stations,modifying operating parameters of the urban drainage system in central control rooms,and scheduling and controlling drainage pumping stations.(1)For the instability of the inflow in the WWTP of the urban drainage system,pumping stations in the upstream of the WWTP are controled as integration,and the PID controller is introduced to control frequency conversion pumps to regulate the outflow of pumping stations.(2)Considering the overflow level of upstream pipes of drainage pumping stations,the relationship between the water level of pumping stations and important nodes in upstream networks,the maximum water level setpoint of existing drainage pumping stations is properly raised,and the utilization rate of storage spaces of pumping basins is increased;(3)More implement of pumps' rotation system in drainage pumping stations,reducing maintenance difficulties of pumps,and improving the reliability and stability of operation of pumping stations.After a period of implementation,the optimal operation strategies of the urban drainage system in The city have achieved remarkable results.The management and operation efficiency of the urban drainage system in the city have been obviously improved.For inflow control of the WWTP,the drastic fluctuation of water quantity in a short time is avoided by integrated control and PID controller.The continuous and accurate control of pumping stations' outflow is realized.The control decreases negative impacts of the high inflow to WWTP and improves the quality of treated water.In addition,according to the guard water level of the drainage network in pumping stations,water level setpoints of pumping stations are raised.The storage amounts are increased of 8.5%~16.7% in the storage capacity of the pumping basins.