考虑储层非均质性的限流筛管完井设计及应用

Design and Application of Limited Entry Liner Completion Considering Reservoir Heterogeneity

现有的限流筛管(LEL)完井和酸化设计没有充分考虑水平井段间及段内储层非均质性对酸化效果的影响。为此,推导了LEL孔眼分布设计解析式,提出了基于“均匀布酸”“均匀酸蚀蚓孔长度”和“均匀酸化后表皮系数”3种设计目标的LEL完井和酸化设计策略,并以中东陆上某油井为例,开展了设计计算。计算结果表明:不考虑储层非均质性时,总孔眼数为198,酸蚀蚓孔长度可达1.36 m,酸化后表皮系数可达-2.88;考虑水平井段间差异后,总孔眼数为135,孔眼的分布更不规律,酸蚀蚓孔长度为0.13 m,酸化后表皮系数为-0.52;考虑纵横向渗透率差异后,总孔眼数为161,各段间孔眼数差异小,酸化后表皮系数为-0.49。所得结论可为碳酸盐岩超长水平井增产设计提供数据参考。

The existing limited entry liner(LEL)completion and acidizing design does not fully consider the influence of reservoir heterogeneity between and within horizontal sections on the acidizing effect.The analytical formula of LEL hole distribution design was derived, the LEL completion and acidizing design strategy based on three objectives(uniform acid distribution, uniform acid wormhole length, and uniform post-acidizing skin factor)was proposed, and design calculation was carried out taking well A in an onshore oilfield in the Middle East as an example.The calculation results show that when the reservoir heterogeneity is not considered, the total number of holes is 198, the acid corroded wormhole length reaches 1.36 m, and the post-acidizing skin factor reaches -2.88. When the difference between horizontal sections is considered, the total number of holes is 135, the distribution of holes is more irregular, the acid corroded wormhole length is 0.13 m, and the post-acidizing skin factor is -0.52.When the difference of vertical and horizontal permeability is considered, the total number of holes is 161, the difference of the number of holes between each section is small, and the post-acidizing skin factor is -0.49. The conclusions provide data reference for the stimulation design of carbonate ultra-long horizontal wells.