摘要
克深井区储层的孔隙结构与裂缝特征造成钻井过程中钻井液大量漏失,其中的固相颗粒会堵塞裂缝,使得部分生产井在完井后产量偏低甚至无产量,现场主要是通过酸压来解决这类问题。对于裂缝性气藏的酸压而言,需要知道钻井液在裂缝中的侵入深度变化,以便于设计施工参数,评价酸压效果。针对这一问题,根据牛顿流体在裂缝中的流动机理,裂缝宽度的变化以及裂缝壁面的滤失等,建立了钻井液在单一裂缝中的漏失动力模型,根据裂缝内钻井液压力的分布来定量描述钻井液的侵入深度,考虑并分析了该模型的侵入深度与侵入时间,压差和裂缝宽度之间的相互关系。最后,利用该模型计算了克深井区获得增产效果的酸压井中钻井液的侵入深度和酸液的侵入深度,通过增产井中二者之间的关系,从而间接证明了该模型。
The pore structure and fractures of the reservoir in the Keshen site of the Kelasu Gas Field cause significant leakage of drilling fluids while drilling.In particular,solid particles block the fractures,leading to low or even zero productivity for some wells after completion.In the field,acid fracturing is mainly employed to remove blockage.The variations in the invasion depth of the drilling fluid in fractures can reflect the performance of acid fracturing.Concerning this issue,according to the flow mechanism of Newtonian fluids in fractures,fracture aperture variations,and filtration losses of fracture walls,a dynamic model for drilling fluid leakage in a single fracture is established.The invasion depth of the drilling fluid is quantitatively described based on the distribution of the drilling fluid pressure inside the fracture.The relationship between the invasion depth and invasion time and that between the pressure difference and fracture aperture are considered and analyzed.Finally,using the established model,the relationship between the invasion depths of the acid and drilling fluid is predicted.The results are compared with the actual values obtained from the Keshen C well,indirectly validating the model.
作者
雷强
唐洪明
张烈辉
朱柏宇
LEI Qiang;TANG Hongming;ZHANG Liehui;ZHU Boyu(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu,Sichuan 610500,China)
出处
《西南石油大学学报（自然科学版）》
CAS
CSCD
北大核心
2018年第4期97-104,共8页
Journal of Southwest Petroleum University(Science & Technology Edition)
基金
国家自然科学基金(5167041601)
国家自然科学基金重点项目(51534006)
关键词
裂缝性储层
钻井液
漏失
致密砂岩
侵入深度
fractured reservoir
drilling fluid
leakage
dense sandstones
invasion depth
