The Study Of Simulation About Urban River Environment

Water is the source of life, is the indispensable valuable resources for the survival of mankind, is an important part of the natural environment, and is the basis conditions about sustainable development of economic and social. The shortage of water resources and the pollution of water sources have become a problem and major issues of social concern in China's urban development. The shortage of water resources is the main contradiction in our country's water resources, and is increasingly becoming a bottleneck about the development of economic and social in our country. And this is one of the major challenges to achieving social objectives. And the pollution of the water environment was aggravated the contradictions about the shortage of water resources.Following the rapid development of economic, the growing urbanization and the transformation of human, the urban river is gradual depredating into a single functional channel of flood controlling and pollutant carrying capacity. The water environment pollution of urban river is particularly become even more noticeable, and is contrary to the overall development of the urban environment. Improving the water quality of urban river, restoring the water environment of urban is very important throughout the eco-city construction at the moment. This paper focuses on Yuxiu River (Jinan, China) restoration project and has a research about simulation of urban river water environment.At present, the effluent parameters are accustomed chosen according to national or local standard at, which have their limitation in restraining phytoplankton proliferation. Chlorophyll-a is selected as the index to show the ecology status of Yuxiu River in this paper. The measurement of decreasing the concentration of nutrient limiting factor is taken to restrain the growth of phytoplankton in the receiving water body according to the principle that organism growth depends on the most lacking nutrient factor. That nutrient limiting factor just is the effluent parameter to be controlled emphatically. The parameter will be also used to calculate and get flow requirement. Finding the nutrient limiting factor is one of targets in this paper.Typical data of 10 indexes for Yuxiu River from May to November are collected such as chlorophyll-a, COD, TN, NH3-N, NO3--N, NO2--N, TP, PO4-, DO and Temperature under the dynamic condition. The relationships between Chlorophyll a and 9 chemical and physical water quality parameters in Yuxiu River are studied by gray relation analysis. These results indicate that ammonia is a more important nutrient limiting factor than others for the growth of phytoplankton. Nitrification and denitrification processes need intensified to decrease the ammonia concentration in effluent for current wastewater advanced treatment plants.Choosing chlorophyll-a as constraint target, and searching for a suitable water quality objective of Yuxiu River. After establishing the one-dimensional water quality model, using Matlab for the water environment simulation and the Linear Programming of the water pollution control. Designing some test programmers to simulating the impact of the water quality along the river when the water quality and quantity is changed at the initial pilot, as well as the impact of the emission about NH3-N on several different reduction rates, proposed the problems on Yuxiu River about sewage treatment.Using the improved method to identifying the water environment capacity of the research reach. Identifying the treatment efficiency of the proposed station on the basis of maintaining the treatment efficiency of bullied stations. Finally using a widely applicated method linear programming (LP) at currently to researching. Through establishing the cost model of sewage treatments, using the costs (Z) minimum as the objective function, getting the treatment efficiency of all stations. Identifying the most emissions plan, then provide the basis data and programme for the ecosystem management and decentralized treatment of urban riverThe research improves the decentralized model of the point pollution source in the urban river. The technical line and results of the research will be provide an important reference and guidance role on the water pollution control technology in other urban rivers.