Peripheral wellblock in low-permeability oilfields feature in discontinuous sand bodies, imperfect well pattern, and invalid injection and production. Conventional fracture technology could not increase single-well output remarkably. For this, we carried out research on energy storage bulk fracturing technology. With lab fracture simulation, net pressure monitoring analysis and lab evaluation on fracturing fluid system, we optimized the fracture parameters, construction dis-placement, liquid volume and fracturing fluid system of special well pattern in old oilfields and energy storage bulk fractu-ring in reservoirs. The displacement optimization result was 4~10m3/min. Fracturing effect was enhanced by matching with complex fracturing fluid system ( slickwater+linear glue+gel) and proppant of multisize particles ( ceramic powder+medium powder+small powder) . Field test showed that net pressure within fractures was increased and micro-fracture opening de-gree was enhanced by alternately adding injecting slickwater and clean water at preflush period. Simultaneous fracturing in oil wells at the same wellblock could increase mutual interference within a certain range, increase output of the wellblock, and improve injection-production relationship. Test results revealed that the energy storage bulk fracturing technology could increase single-well output while reducing cost, and enable the peripheral wellblock of old oilfields to realize economic and efficient development.%低渗透油田外围井区砂体不连续,井网不完善,注采不见效,常规压裂技术无法显著提高单井产量,针对此问题,开展蓄能整体压裂技术研究.采用室内裂缝规模模拟、裂缝净压力监测分析及压裂液体系室内评价方法,对老区特定井网和储层条件下蓄能整体压裂的裂缝参数、施工排量、用液量及压裂液体系进行优化,排量优化结果为4 ~10m3/min,配合复合压裂液体系 (滑溜水+线性胶+冻胶组合)、多粒径组合支撑剂 (粉陶+均陶+小陶) 提高压裂改造效果.现场试验表明,前置液阶段滑溜水与清水交替加入,增加裂缝内的净压力,提高微裂缝开启程度; 同一井区油井同步压裂,能增加裂缝在一定范围内的相互干扰,提高井区的产量,改善注采关系.试验结果表明,蓄能整体压裂技术能够在控制投入成本的同时提高单井产量,实现老油田外围井区经济有效开发.
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