摘要
针对斜井段砂粒沉降的问题,建立了砂粒两相流动数值模型,并结合现场井眼参数,将模型简化,建立了冲砂管柱与井筒在斜井段的环空流体仿真模型;研究了斜井段砂粒沉降的规律,分析了排量、冲砂液黏度、砂粒大小、冲砂液密度、井斜角等因素对砂粒沉降的影响,并结合多个影响因素进行正交试验。研究结果表明:在斜井段冲砂过程中环空宽间隙处砂粒平稳运移,主要以层流方式上返运动;环空窄间隙处砂粒主要以翻滚、迂回、跃移的形式进行运动,砂粒运移速度明显滞后于环空宽间隙处,且部分砂粒会聚集、回旋并沉积,主要沉积在斜井段末尾接近水平段处;各影响因素中,砂粒粒径及冲砂液黏度对携砂效果影响最大,冲砂液排量影响次之,冲砂液密度对携砂效果的影响较小。综合试验结果,建议现场作业冲砂液排量选取为800 L/min左右,所使用的冲砂液黏度为35~45 mPa·s,推荐胍胶液质量分数为0.1%~0.3%。研究结果可为水平井安全高效作业提供一定的指导。
Sand production often accompanies the exploitation of highly deviated wells,extended reach wells and horizontal wells.Sands gradually deposit to form sand beds,which affect oil exploitation.Especially,in deviated well sections,sand settling easily occurs to block oil pathway,increase flow resistance,and even damage downhole equipment.To address the issue of sand settling in the deviated well section,a numerical model of sand two-phase flow was built.Then,the model was simplified depending on field wellbore parameters.Moreover,a simulation model of annular fluid between the sand washing string and the wellbore in the deviated well section was built to understand the pattern of sand settling in the deviated well section,and analyze the influences of the factors such as displacement,sand washing fluid viscosity,sand particle size,sand washing fluid density and inclination on sand settling.Finally,orthogonal tests were conducted with consideration to multiple influential factors.The results show that during the sand washing process in the deviated well section,at wide gap of annular space,sand particles migrate smoothly,and mainly move upward in a laminar flow form;at narrow gap of annular space,sand particles mainly move in the form of rolling,meandering and saltation,the sand particle migration velocity is significantly slower than that at wide gap of annular space,and some sand particles accumulate,swirl and deposit mainly at the end of the deviated well section near the horizontal section.Among the influential factors,the sand particle size and sand washing fluid viscosity have the greatest impacts on the sand carrying effect,followed by the sand washing fluid displacement,and the impact of the sand washing fluid density on the sand carrying effect is relatively small.Based on the test results,it is proposed to select a sand washing fluid displacement of around 800 L/min,sand washing fluid viscosity of 35-45 mPa·s and guar gum fluid concentration of 0.1%-0.3%for field operation.The study results provide guidance
作者
纪海涛
冯定
孙巧雷
王尚卫
侯学文
黄成彬
Ji Haitao;Feng Ding;Sun Qiaolei;Wang Shangwei;Hou Xuewen;Huang Chengbin(School of Mechanical Engineering,Yangtze University;Hubei Engineering Research Center for Oil&Gas Drilling and Completion Tools;Oil and Gas Technology Institute,PetroChina Changqing Oilfield Company)
出处
《石油机械》
北大核心
2024年第10期108-116,共9页
China Petroleum Machinery
基金
湖北省技术创新专项(重大项目)“智能油气钻采井眼轨迹控制工具研究”(2019AAA010)
中国石油天然气股份有限公司长庆油田分公司油气工艺研究院科研项目“页岩油长水平井冲砂流体流动特性与管柱优化研究”(22JX-FW-003)。
关键词
冲砂
斜井段
砂粒沉降
携砂效果
正交试验
sand washing
deviated well section
sand settling
sand carrying effect
orthogonal test
