深层致密砂砾岩储层盐227区块为厚层特低渗常压油藏，常规直井压裂效果差、建产难，单一水平井开发难以实现纵向厚层有效动用。借鉴国外页岩气工厂化开发理念，发展了“三层楼”工厂化整体压裂开发模式，即1套层系、3层开发，8口水平井组作为一个整体进行压裂，第一层为3口井，第二层为3口井，第三层为2口井，水平段长900～1400 m ，三层之间纵向跨度为80 m。综合考虑平面上同层井间、纵向上层间裂缝参数匹配，建立层间立体体积缝网，提高储量控制程度。通过优化施工参数，应用新型实时混配压裂液技术，配套泵送桥塞分段压裂工艺、裂缝实时监测技术，完成4个井组8口井87段的集中压裂，裂缝监测显示立体缝网基本形成。工厂化整体压裂平均施工周期比单一水平井压裂缩短50％，单井投产费用减少395.5万元。压裂后单井平均产油量11.8 t/d ，为同区块直井的4倍以上，取得了良好的改造效果，为今后同类致密油储层的经济开发积累了经验。%Block Yan 227 is a thick tight sandstone-conglomerate reservoir with ultra low permeability . The result of fracturing in a conventional vertical well was too poor to obtain a satisfactory yield ,to the point that it is even not desirable to develop such a thick reservoir with a single horizontal well .Based on the concept of factory production from numerous countries for shale gas ,a three-layer development model was developed .The model included a group of eight horizontal wells for fracturing :three wells were includ-ed in the first layer ,another three wells in the second layer ,and remaining two wells in the third layer .The length of the horizontal section ranged from 900 to 1 400 m ,the vertical span in the three layers was 80 m . Fracture parameter matching was done with wells within the same layer as well as between layers to estab-lish a 3-D fracture network to improve the controlling degree of reserves .Operating parameters were opti-mized ,with a new type of real-time mixing technology for fracture fluids ,which included pumping a bridge plug for staged fracturing ,and monitoring fractures in real time ,which allowed eight wells in four well groups with 87 sections to be fractured .The fracture monitoring results showed that a 3D fracture network was formed .The centralized multi-well fracturing technology has many advantages compared with single horizontal well fracturing ,including the fact that average operation cycle time was shortened by 50% ,and the production cost of a single well was reduced by 3.955 million RMB .After treatment ,average daily oil production of single well was 11.8 t/d ,which was four times higher than that in the vertical well in the same block .It is a good experiment for economic recovery in similar tight oil reservoirs .
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