垂直井筒低黏度液流最小携砂速度研究

Research on critical sand transportation velocity for low Viscosity liquid flow in vertical well-bore

刘爱萍 邓金根

LIU Ai-ping DENG Jin-gen

中国石油大学石油天然气工程学院, 北京 102249

Faculty of Petroleum Engineering in China University of Petroleum, Changping 102249, Beijing, China

油气井出砂开采或储层出砂后的垂直井筒最小携砂速度是井筒携砂的重要设计参数,一般的方法是对颗粒自由沉降末速附加一个固定的修正系数。基于理论和试验分析,用颗粒的等沉降速度当量直径取代了等体积当量直径,进而利用沉降试验解决了颗粒的形状系数测定问题,并通过携砂试验得到了埕北地区东营组油藏砂粒的最小携砂速度计算公式。研究结果表明,在低黏度流体中最小携砂速度的修正系数随颗粒直径减小而增加,在携砂试验条件下其变化范围为1.45~2.90。研究成果可用于计算垂直井筒内低浓度砂粒无淤塞的最低携砂流速,对于解决其他地质区块和微小颗粒的垂直井筒携砂问题具有借鉴意义。

After well or reservoir sanding,critical sand transportation velocity is an important parameter for sand transportation design of vertical well bore.It can be worked out by adding a fixed coefficient of correction to the granule free settling terminal velocity.Based on theoretical and experimental analysis,the problem of shape coefficient measurement is solved through conducting granule settling experiment in virtue of the replacement of the equivalent diameter of equal volume by the equivalent diameter of equal sedimentation velocity.In addition,the formula of critical sand transportation velocity is established for the Dongying formation reservoir of Chengbei area through sand transportation test.The research results show that the correction coefficient of critical sand transportation velocity l increases with the decrease of the granule diameter in low viscosity fluid.It varies from 1.45 to 2.90 under conditions of the critical sand transportation experiment.These results are available to calculate the critical sand transportation velocity of no silting in vertical well bore of low sand grain concentration and can be referred to solve the sand transportation difficulties of vertical well bore in other areas.

10.3969/j.issn.1000-7393.2007.01.010