射孔孔眼磨蚀对分段压裂裂缝扩展的影响

发布时间：2018-06-20 05:10

本文选题：非常规油气藏 + 水平井　；参考：《天然气工业》2017年07期

【摘要】：非常规油气藏分段压裂施工中常利用射孔限流法促进段内多条水力裂缝均匀发育,压裂过程中,支撑剂会逐渐磨蚀射孔孔眼,致使射孔孔眼的限流作用失效。为研究射孔孔眼磨蚀现象对分段压裂中多裂缝发育的影响情况,耦合了孔眼磨蚀模型和水力裂缝扩展模型,建立了考虑射孔孔眼磨蚀的水平井分段压裂裂缝扩展模型。模拟结果表明:随着支撑剂磨蚀破坏射孔孔眼,孔眼的限流能力显著下降,导致压裂段内各水力裂缝尺寸差距增大。基于所建立的数值模型,研究了不同支撑剂浓度、压裂液排量条件下射孔孔眼磨蚀对压裂段内多条水力裂缝扩展的影响。结果表明:(1)压裂液内支撑剂浓度越高,射孔孔眼初期的磨蚀速度越快;(2)支撑剂浓度变化对段内裂缝扩展延伸的影响较小;(3)压裂液排量越高,射孔孔眼限流效果越好,压裂段内各裂缝发育越均匀。最后建议在分段压裂施工中尽可能提高压裂液排量,这将有助于压裂段内各裂缝的均衡发育。
[Abstract]:Perforating flow limiting method is often used to promote the homogeneous development of multiple hydraulic fractures in unconventional oil and gas reservoir fracturing. During fracturing, proppant will gradually erode perforated holes, resulting in the failure of the flow limiting effect of perforating holes. In order to study the effect of perforating hole abrasion on the development of multiple fractures in segmental fracturing, the model of hole abrasion and hydraulic fracture propagation was coupled, and the fracture propagation model of horizontal well was established. The simulation results show that with the abrasion of proppant to destroy the perforating hole, the flow limiting capacity of the hole decreases significantly, resulting in the increase of the hydraulic fracture size gap in the fracturing section. Based on the established numerical model, the effects of perforating hole abrasion on the propagation of multiple hydraulic fractures in fracturing section under the conditions of different proppant concentration and fracturing fluid discharge are studied. The results show that the higher the concentration of proppant in fracturing fluid, the faster the abrasion rate in the initial stage of perforating hole is. (2) the effect of concentration of proppant on the extension of fracture is smaller than that of proppant concentration in fracturing fluid) the higher the discharge rate of fracturing fluid is, the better the flow limiting effect of perforating hole is. The more uniform the fracture development is in the fracturing section. Finally, it is suggested that the fracturing fluid discharge should be increased as much as possible in the fracturing operation, which will be helpful to the balanced development of each fracture in the fracturing section.
【作者单位】： "油气藏地质及开发工程"国家重点实验室·西南石油大学;中国石油西南油气田公司勘探开发研究院;
【基金】：国家自然科学基金重大项目“页岩地层动态随机裂缝控制机理与无水压裂理论”(编号:51490653) 国家重点基础研究发展计划(973计划)项目“中国南方海相页岩气高效开发的基础研究”(编号:2013CB228004)
【分类号】：TE357

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