The Feasibility Research Of Xi'an Decentralized Wastewater Reuse And Engineering Example Analysis

With the increase of population, urbanization, the development of industry and agriculture, Water shortage and pollution becomes one of the main problems facing in China, Xi'an is a serious water shortage in the country's 40 cities. Water recycling and reusing becomes one of the most important ways to solve the shortage of water resources in Xi'an. Large-scale treatment of sewage pipe network requires a corresponding range of construction and sewage collection basin, which requires huge systems, and huge investment. Operation and maintenance costs are high. Scientists are actively advocating decentralized sewage disposal and recycle in order to realize water recycle and water balance. Combining with the "Xi'an integrated water resources planning", "Xi'an reclaimed water planning"etc, through field survey, data collection, theoretical analysis, the feasibility of decentralized wastewater reuse in Xi'an has been studied, the main research results are as follows:(1) Through a comprehensive survey of the Xi'an city situation, which including the water resource, water supply system, sewage treatment etc, the paper analyzed the situation of water resources utilization, the balance of supply and demand situation and developing trend of Xi'an;(2)The paper also forcasted the potential demand of reclaimed water in Xi'an using correlation analysis, putting forward the necessity of decentralized sewage disposal and recycle;(3) The Paper selected two representative decentralized systems (residential district and high school), through which to predict the amount of reclaimed water, Established by CVM distributed in water use, economies of scale will pay the minimum function, and in accordance with the existing decentralized wastewater reclamation and reuse projects operating cost model, the price of tap water and distributed to determine the minimum sewage treatment facilities economies of scale;(4) Through reference and investigation of investment, operating costs and economic benefits of existing decentralized waste water recycling systems in Beijing (using Biochemical-physico-chemical treatment technology), combined with Xi'an circumstances, come to the relationship between the investment of unit volume of sewage treatment and design size, as well as the operation cost under different percentages of the total running water. The paper has estimated the typical college and the residential area of Xi'an's wastewater reuse project investment, and the project running costs under different sewage treatment capacity as well as project cost (direct economic benefits and indirect economic benefits), and demonstrated by examples of decentralized wastewater reuse is feasible.