摘要
稠油水平井出砂后发生井筒砂埋是造成油井产能下降、作业成本增加的关键原因之一,研究稠油水平井中地层砂的运移规律,可为稠油水平井生产设计提供依据。通过水平井携砂能力试验,测量不同稠油黏度和稠油比例条件下水平井筒中地层砂的临界携砂流速,定义了稠油比例黏度系数和稠油极值比例黏度系数,探究稠油黏度和稠油比例对水平井筒中地层砂运移的综合影响。结果表明:增加稠油比例或稠油黏度,水平井筒中地层砂临界携砂流速均会先降低后趋于稳定并呈现轻微上升的变化趋势,水平井筒中地层砂临界携砂流速随稠油比例黏度系数先降低后增加,且存在一稠油极值比例黏度系数使得地层砂运移的难度和砂埋风险最低。基于试验结果提出一套用于稠油水平井开采时防砂埋风险的生产优化方法,即通过测试地层砂对应的稠油极值比例黏度系数,对油井实际稠油比例黏度系数进行调整,以降低地层砂在水平井筒中沉积的风险。现场应用结果表明:该优化方法可有效降低井筒砂埋的风险,对于提高油井经济效益、保证油井稳产高产具有一定的指导意义。
The sand burial caused by sand production in horizontal wells of heavy oil reservoir is one of the key reasons for the decline of oil well production capacity and the increase of operating costs.In order to study the regularity of formation sand migration in heavy oil horizontal wells and provide basis for production design,this paper conducts a horizontal well sand carrying capacity test to measure the critical sand carrying velocity of formation sand under different viscosity and ratio conditions of heavy oil.The paper defines proportional viscosity coefficient and the extreme proportional viscosity coefficient to explore the comprehensive effects of heavy oil ratio and viscosity on the formation sand migration in horizontal wellbore.Then,the paper proposes a set of production optimization methods for heavy oil horizontal well to prevent sand burial.The result indicates that increasing the proportion or viscosity of heavy oil makes the critical sand carrying flow rate first decrease and then tend to be stable and show a slight upward trend.And the critical sand deposition velocity of the sand decreases first and then increases with the proportional viscosity coefficient.There also exists an extreme proportional viscosity coefficient,which makes the risk of sand burial and sand migration lowest.Based on the experimental results,the paper proposes a set of production optimization methods suitable for horizontal wells preventing sand burial,that is,to test the extreme viscosity proportional coefficient of the formation sand,and apply the actual viscosity ratio coefficient of the well to reducing the risk of formation sand deposition in the horizontal wellbore.The application shows that the optimization method can effectively reduce the risk of sand burial in the wellbore,which has certain guiding significance for increasing the economy benefit and ensuring stable production and high yield of oil wells.
作者
周瑞国
李志强
ZHOU Ruiguo;LI Zhiqiang(Weifang Geotechnical Investigation and Surveying Institute,Weifang 261000,China;Anqiu Planning and Architectural Design Institute,Anqiu 262100,China)
出处
《安全与环境工程》
CAS
北大核心
2019年第4期177-182,189,共7页
Safety and Environmental Engineering
基金
内蒙古地质勘查基金项目(13-4-KC28)
关键词
稠油
水平井
砂埋风险
稠油比例黏度系数
生产优化
携砂能力试验
heavy oil
horizontal well
sand burial risk
proportional viscosity coefficient of heavy oil
production optimization
sand carrying capacity test
