Study On Pollution Control Of Dongdong Estuary Based On Water Environment Capacity Of Open Sea Area

At present, China’s environmental pollution of the coast and the offshore was not under effective control yet. Rivers that carry pollutants into the sea and terrigenous sewage discharging into the sea are the main causes that affect the nearshore marine environmental quality in China. Large amounts of sewage into the sea will exacerbate the pollution of sea water, affecting marine function, constrainning the sustainable development of marine economy, and may even threaten marine ecosystems. Estuaries are the heaviest polluted area in our country. On the basis of making full use of sea water environmental capacity, the implementation of the estuary of the sea pollution total amount control can not only alleviate the pollution of water environment of this area, but also maximumly satisfy the needs of terrigenous pollution, thus providing environmental protection for social and economic development.This paper takes sea area of Rudong in Jiangsu Province as the study area, confirming marine environment status and the flux of dye into the sea of Beiling gate, Yangkou gate, Juejv gate, Dongan gate, and Yaowang gate through data collection and field investigation. This paper reviews the environmental capacity of research and application situation home and abroad, analyzes the pollutant dispersion characteristics of Rudong marine, and determines the scope of the mixing zone based on the equilibrium stability diffusion field. This paper studies and identifies sea water environmental capacity in the design of average daily flow rate and maximum concentration of pollutants into the sea discharge of 6 hours and 3 hours respectively.This paper investigate the situation of the concentration of the pollutants and the flow in different seasons, discovering the estuary actual discharge condition can not make full use of the marine environmental capacity, Based on this, the programs will be put forward. With the mathematical programming method, the program, which is based on the sea flow, concentration and discharge time of the river pollutants discharge pollutants into the sea, should meet the objective function and constraint condition. Research has shown that CODCr emissions of Beiling gate is in good condition, total phosphorus need to cut 195.543 t/a.CODCr emissions of Yangkou gate is in good condition, so it does not need to cut, total phosphorus need to cut 361.271 t/a; CODCr emissions of Juejvgate must be cut 12147.48 t/a, total phosphorus need to cut 335.371 t/a. CODCr emissions of Dangan gate must be cut 12823.43 t/a, total phosphorus need to cut 241.089 t/a.