Research On Water Injection Development Rule And Adjustment Method For Horizontal Wells Of Reservoir With Low Permeability

At present, drilling technology and experience of horizontal wells, which are used fordevelopment on Putaohua reservoir on the east of Changyuan, Dangqing, was already mature.However, research on water injection exploitation rule and adjustment method for horizontalwells was not deep and comprehensive. It lacks of theoretical guide and hardly meets thedemand of reservoir. The article, aiming at reservoir characteristic, conducted study onhorizontal well development pattern, water injection development rule, capacity and itsinfluencing factors, and reserves estimating method, proposed a reasonable aggregateadjustment method.The thesis mainly obtained following results:1. Optimize the advantage well pattern that was fit for reservoir characteristic anddevelopment characteristic of Putaohua with low abundance, namely “seven points’ parallel”mixed developing pattern. The length of horizontal segment was500m, with300m ofsandstone that is oilness.2. Under the condition of advantage well pattern, considering fault, lithology,sedimentary characteristics, the horizontal well control reserves calculation according tostreamline trap area calculation method was studied, and it was applicable and reliable; Thelower limit of effective thickness of0.5m, permeability lower limit for10×10-3μ m2.3. Apply stable seepage and unstable seepage theory to studying the horizontal wellproductivity prediction method, with the relative error generally within10%.4. Horizontal well production factor chart was established; Two horizontal well ratioanalysis chart was established. Horizontal well water flooding control the proportions of thelength, thickness of water injection well water flooding beneficial technology limit was60%.5. Horizontal well water flooding by the effect of time was generally in6~12monthsafter injection Wells betting, accumulated injection-production ratio about2.0, the output wassegmented by effect or single step by rising characteristics, injected water breakthrough inhorizontal Wells near the endpoints.6. Horizontal well production decline type for the hyperbolic decline, productiondecreasing amplitude of the first year at20~30%, the effect the year after water injectiondecline rate was within18.0%. Advanced water injection production Wells decreasingamplitude was small, lagging water decreasing amplitude was bigger.7. In order to improve the injection-production relationship that was given priority to thelow abundance of putaohua reservoir comprehensive adjustment technology, a "vertical Wellsand asymmetric water injection, horizontal sublevel fine adjustment" appropriate technologywas formed, measures to adapt to the characteristics of thin reservoir optimization andoptimization technology was carried out, innovation in the horizontal well "use and adjustevery block, the realization of water control in stages and phases capacity to replace" new ideas were all realized.The article carries out the low abundance of putaohua reservoir horizontal well waterflooding development rule and adjustment method research which will be promoted in theperipheral daqing oil sheet in the horizontal scale, high level and high benefit development,have important guidance and reference for similar oilfield development effect, has greateconomic and social benefits.