Research On Long Distance Water Conveyance Project In Cascade Pumping Stations Site Selection

China's water resources are scarce,and water resources in the time and space uneven distribution. With the development of urbanization and the improvement of the people's living standard, the contradiction against water supply and water demand is becoming more and more seriously, long distance water transfer projects are becoming increasingly critical. The long distance water conveyance project of cascade pumping station is a complex system engineering,its design, construction, operation and management level will directly affect the safety and economic benefits of the project. Selection of pumping station site, water pipe diameter and wall thickness in engineering design have more important theoretical and practical significance.Based on the water supply project of an industrial park in Shaanxi Province, in order to reduce its cost, this paper systematically studies the site selection, the diameter of the pipeline and the wall thickness of the long distance water conveyance project of cascade pumping station. The main contents of this paper are as follows:(1) Take the sum of the minimum cost of the current value of the pipeline, the present value of the annual electricity consumption and the current value of the annual maintenance cost of the pipeline to established mathematical model, to determine the long distance cascade water pump station at all levels of the head distribution, site location.(2) In order to minimize the cost of long-distance water supply pipeline, in the calculation of pipeline investment costs, the mathematical model is established by taking the minimum cost of investment cost and infrastructure construction as the objective function. The paper puts forward the method of using different wall thickness in different pressure section of the pipeline to reduce the investment of pipeline engineering.(3) Take the sum of the minimum cost of the present value of the investment pipeline, the present value of the annual electricity consumption and the present value of the pipeline maintenance fee as the objective function to established mathematical model. Considering the different initial and long-term water flow, the pump running scheme is different, the pump working head and the pump unit working efficiency is different, and China's implementation of two-part electricity price and other factors, to study the long-distance pump water transport project economic diameter. Taking a long distance pump water supply pipeline project in Shaanxi as an example, the process of determining the economic diameter of three kinds of water supply pipes such as DN500, DN600 and DN700 is introduced, which provides reference for the economic diameter selection of similar long distance pump water supply project.(4) Combined with the water supply project of an industrial park in Shaanxi Province,take the sum of the minimum cost of the current value of the water supply pipeline, the present value of the annual electricity consumption and the present value of the annual maintenance fee to established mathematical model, which ultimately obtain the cascade pump station site selection scheme.