Research On Monitoring The Operational Efficiency Of Eco-sponge City Facilities And Improving River Water Quality Simulation Research

Rainfall runoff pollution directly enters the river without treatment will affect the water quality of the main stream of the river.At present,there are many treatment technologies used in the design of river improvement projects.However,in order to restore the river to pay more attention to ecology,various ecological measures have been gradually promoted and used.The development of it and the research on the initial rainwater pollution problem in a certain area have important practical significance for the local selection of scientific,appropriate,economical and effective rainwater treatment measures and the protection of the water ecological environment.In view of this,this study selected the ecological sponge city facilities used in the watershed of the study area as the research object,carried out on-site monitoring during the rainfall period,analyzed the removal effect of the selected pollutant indicators by the facility,and discussed the difference in the removal rate of pollutants and their differences.The relationship of rainfall,summed up the removal rate of each pollution index under light rain,moderate rain and heavy rain.Based on the collected watershed hydrology and water quality measured data,a one-dimensional hydrodynamic-water quality model reflecting the migration law of river pollutants was established,and then the model was used to simulate the impact of system removal differences on the water quality of the main stream of the river under various rainfall levels.On the basis of theoretical analysis,field monitoring and simulation,the following conclusions are obtained:(1)The fuzzy evaluation method in the water quality evaluation method is combined with the comprehensive pollution index method.According to the weight coefficient of each index,it is known that the main pollutants in the basin are mainly ammonia nitrogen and total phosphorus,and the water quality of the river deteriorates along the way.The water quality in April was Grade V.A comparative analysis of the water quality in each month of the year shows that the water quality in the dry season is worse than in the wet season;(2)Based on the ecological sponge city facilities built in the basin,the system has carried out research on the removal of pollutants in rainwater under different rainfall intensities.It is found that the removal rate of ammonia nitrogen and total phosphorus in the system during moderate rain is the highest,and the removal of COD under various rainfall levels The rate is relatively volatile,and the removal rate of SS is relatively stable;(3)Based on the collected watershed hydrology and water quality actual measurement data,a one-dimensional river hydrodynamic-water quality model was established.The calibration proved that the established model has good practicability for studying river water quality,and the errors in the hydrodynamic and water quality modules are all within reach.Within the acceptable range,it can be used for subsequent program simulation;(4)Based on the built water quality model and the pollutant removal rate obtained by monitoring,simulate the impact of the outflow of the ecological sponge city facilities built in the basin on the water quality of the river,and launch the simulation of the system construction location and different outflow and flow combinations.The results show that under the premise of ensuring the stable water quality of the effluent,the closer the location is to the upstream,the greater the effluent flow,the stronger the improvement of the river water quality.At the same time,it was learned that under heavy rain or rainfall intensity above heavy rain,the system can improve the water quality of the river,but the effect is limited.It needs to be integrated with other measures in the river basin renovation project to perform comprehensive control to ensure that the water quality of the downstream handover section meets the standard.