塔里木盆地玉北地区储层损害机理主要表现为碱敏程度中等偏强,储层水锁损害严重.针对以上损害机理,通过加入理想充填暂堵剂、无荧光仿沥青和超低渗透成膜剂,形成了钻井液优化配方,其高温高压滤失量可降至小于12 mL,岩心渗透率恢复值可达85％以上,达到储层保护的要求;建立了暂堵剂粒度分布与储层裂缝宽度上限值之间的匹配关系:当缝宽上限小于150μm可使用超细碳酸钙;当储层缝宽上限值大于150μm之后,应使用超低渗透成膜剂和无荧光仿沥青.玉北5井和玉北9井的现场试验表明,所使用的优化四开钻井液性能优良,井浆的岩心渗透率恢复值达到87％以上,对储层的保护达到预期效果.%To protect the reservoirs in block of Yubei Tarim basin that are of high alkali and water sensitivity, the temporary sealing additives, bloomless asphalt and ultra-low penetration additives are applied to form a drilling fluid formulation, which the HTHP filtration rate is less than 12 mL, the core penetration recovery rate is over 85%, and the relationships between temporary sealing particle size distribution and fracture width are ultra-fine calcium carbonate can be used while the largest fracture width is less than 150 μm, and if the largest fracture width is more than 150 μm, the bloomless asphalt and ultra-low penetration additives can be applied. The applications in well Yubei5 and Yubei9 show that the core penetration recovery rate is over 87%, which can protect the reservoirs effectively.
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