The Research On Optimization And Adjustment Methods Of Gathering And Transporting Pipeline Network In Water Flood Oilfield With Low Permeability

Among the oil field construction investment, surface engineering cost occupies 30%~40% of the entire developing investment at oil field, and it occupies 60%~70% of the gas field investment. Generally speaking, the quantity of construction engineering and investment of both oil-gas gathering and transportation system and disposal system occupies 60%~70% of the whole surface engineering. The cost of gathering and transportation system and management system occupies 30%~40% of the entire crude oil production cost, thereinto the gathering and transportation cost occupies 60%~80%, and 90%~97% of these energy cost is heat energy. Optimizing pipe net framework, reducing pipeline amount, optimizing gathering and transporting parameter, selecting reasonable gathering and transporting manner, accordingly realize low energy cost, low investment, high benefit and high level during the course of gathering and transportation.Combining the field practice demand, with minimum pipe net investment as target function, this paper establishes topology optimization mathematical model of ramiform and orbicular pipe net system, and according to the model structure character, adopts grades optimization method to resolve it. With minimum pipe net investment and running fare as target function, the paper establishes parameter optimization mathematical model of ramiform pipe net, and adopts POWELL combining mixed SUMT methods to resolve this model. According to diathermanous principle of gathering and transportation pipelines heated by electricity, the paper establishes physical and mathematical models of pipeline transporting heat, resolves the models by emendation estimated in advance, and then can calculate the needed power of gathering and transportation pipelines heated by electricity under different states. Under steady condition, the paper establishes physical and mathematical models of soil temperature field around pipelines heated by electricity, resolves them by limited difference method, and can work out the earth temperature at certain depth on each day in a year. With the lowest first investment of gathering and transportation pipe net heated by electricity and running cost as target function, the paper establishes the design parameter model of ramiform gathering and transportation pipe net heated by electricity, then woks out that the best heat preservation layer thickness of gathering and transportation heated by electricity in Aonan is 38mm and economic depth is 1.2m. With the lowest investment and running cost as target function, the paper establishes gathering and transportation optimization mathematical model of newly increased production at block fields, and can make sure reasonable gathering and transportation manner, the best offloading oil location, logical conversion transportation occasion, the best time of closure, halt, consolidation and transition at every disposal station. Aiming at subsistent problem of surface engineering at NO.9 production plant, this paper combines optimization software, and brings forward regulatory measures of gathering and transportation.