Study Of Bearing Capacity Of Water Environment Based On Wastewater Regeneration And Reuse In Yinchuan City

The bearing capacity of water environment can reflect the maximum supporting capacity of water environment system to regional development and affect the scale of urban sustainable development.With the process of urbanization,water resources shortage and water environment pollution are becoming more and more serious,which makes the carrying capacity of water environment decrease,and then seriously restricts the social and economic development of the region,and cause a vicious circle.The reuse of sewage water is reliable,large,stable and has a certain effect of anti fouling,which is one of the effective ways to improve the carrying capacity of water environment.Therefore,study on water environment carrying capacity of Yinchuan based on wastewater recycling and reuse has a greatsignificance to optimize the wastewater recycling and reuse system,improving the quality of water environment maintain the sustainable development of urban economy,society and environment.The main research contents and results are as follows:(1)By means of literature review,the concepts and methods of wastewater reuse and water environmental bearing capacity were studied,and the system dynamics method was selected as the main research method.On the basis of comprehensive consideration of data collection,data reliability and feasibility of evaluation methods,the grey relational model is applied to screen the evaluation index system of water environmental carrying capacity,and the weight of each index is further determined.On the basis of this,the concept of membership degree in fuzzy mathematics is used to describe the bearing degree of water environment,so as to prepare for the quantification of water environment carrying capacity in Yinchuan.(2)According to the modeling theory of system dynamics,the structure of urban water environment system is analyzed.The system is divided into three subsystems:society,economy and environment,and the environment subsystem is further divided into water resources supply and demand subsystem,wastewater recycling subsystem and water environment subsystem.The feasibility of reusing reclaimed water in all directions was discussed.The feedback relation between wastewater reuse and the variables of each subsystem is analyzed,and the functional relationship between the variables is determined,and the system dynamic model of water environment carrying capacity based on wastewater reuse is established.The calculation method of the related parameter pairs in the model is given,and the reliability of the model is verified.(3)Taking different growth rate of wastewater reuse as decision variable,four kinds of development schemes of wastewater recycling in Yinchuan were designed and simulated with the model.The results of operation of the model are good,which shows that the model has practicability.The evaluation index system and quantitative calculation method of water environment carrying capacity of Yinchuan under different wastewater reuse schemes were used to calculate the(4)carrying capacity of water environment in Yinchuan.The results show that the water environmental carrying capacity of scheme 1 and historical year is in a weak bearing state,the other three schemes is in a loadable state.It can be seen that the construction of sewage recycling and reuse has a certain contribution rate to improve the water environment carrying capacity of Yinchuan,among which the water environment carrying capacity of Yinchuan under scheme 4 is the highest.It can be used as the optimal development strategy of wastewater recycling and one of the measures to enhance the water environment carrying capacity of Yinchuan.