Study On Water Quality Control And Engineering Application Using Numerical Technology

Along with social economy development, the ability for human to transform the nature is rapidly enhanced. But it also leads to a series of environmental problems at the same time. The water environment is the most serious area, which is inflicted by human disturbance and destruction. The water environment pollution has become one of the most important environmental problems around the world. In that context, the problems of health, safety and reasonable development for water environment, get the more and more attention of mankind. The water quality and supply security of drinking water source directly affects resident health. The construction of waterfront area has a large impact on the resident living environment and regional ecological environment. Therefore, it is of great theoretical and profound significance for us to predict and control the water quality problem. It is necessary to explore its engineering application. Specifically, the main achievement of this research is as follows:Firstly, on the basis of hydrodynamic and water quality model, the water exchange process of reservoir was simulated. The spatial and temporal trend of water quality in reservoir was predicted. A method of reservoir eutrophic state grade was developed by the combination of eutrophic state evaluation and EFDC model for the first time. It achieved the spatial and temporal evaluation of eutrophic state quantificationally. The influence of nutrient and temperature on algal growth was analyzed. The measures for water quality improvement were put forward and the optimization one was obtained by comparing to the results of simulation. This study provided a scientific guidance for the work of water quality control in a reservoir. It was of profound significance for water environment protection and supply security of drinking water source.Secondly, on the basis of the research on water quality control, two studies about the practical engineering application were conducted:(1) Prediction of space-time evolution process for water pollution emergency and the real-time assessment for its riskThe model of water pollution emergency for open channel system was built. It achieved the prediction of space-time evolution process for water pollution emergency.The water pollutant transport in representative situations was simulated. The real-time assessment system combined with EFDC model for risk of water pollution incidents was built. The concept of space-time change weight for risk factor is put forward. An emergency system for water pollution incidents was also established. The results provided a scientific basis for the decision makers to take effective measures. It had very important ecological, economic and social meaning to the protection of water source.(2) Quantitative prediction of the feasibility for waterfront project and scheme optimizationThe EFDC numerical simulation technology was applied to the construction of waterfront. It realized the quantitative prediction and evaluation of the feasibility for waterfront project. The quantitative evaluation of the implementation effect of waterfront project included the aspects of geometry, landscape, water erosion,vegetation growth, water exchange process and water quality. By predicting the implementation effect of project, the feasibility of project and an optimal blue print was obtained. The improving methods are proposed in the end. The study provided important guidance for engineering construction in waterfront area.