疏松砂岩油藏出砂机理室内试验研究

EXPERIMENT OF SANDING PRODUCTION MECHANISMS IN UNCONSOLIDATED SANDSTONE RESERVOIRS

吕广忠 张建乔 孙业恒

Lv Guangzhong Zhang Jianqiao Sun Yeheng

胜利油田有限公司地质科学研究院, 山东东营 257015 中国石油大学机电工程学院, 山东东营 257061

为研究疏松砂岩油藏出砂机理,对地层出砂进行了室内试验研究。利用玻璃板填砂平面模型,对影响地层出砂的非均质性、黏度、渗透率和流体渗流速度等因素进行了研究。结果表明,大孔道的形成是一个在主流线上分枝发展的"灾变"过程。在临界出砂速度以上,随流速的增大,出砂速度迅速提高;胶结强度越高,出砂量和出砂速度越小;在相同的渗流速度下,渗透率越大,出砂量越小;随着原油黏度的增加,出砂量增加。出砂量的变化表明,胶结程度和水力冲刷是影响油层出砂的重要因素,大孔道一旦形成,油井含水率增加,油藏的采收率降低36%。试验结果为现场防止出砂提供了参考依据。

The experiments were used to study the sanding production mechanism in Unconsolidated Sandstone Reservoirs.The effects of sanding production are investigated using the sand-packed glass plate model.The factors influencing heterogeneity,mobilization,permeability and fluid velocity are analyzed.The experiment results show that macroscopic throats forming is a catastrophic process in main stream line.Above a critical sand producing velocity,with the increment of the flow velocity,sand producing velocity increases quickly, and cementation intension is more higher,the content and velocity of sand producing are smaller than before.Under the same percolation flow velocity,the content of sand producing is smaller with the bigger permeability.The content of sand producing increases with the increase of crude oil viscosity.The variety of a sand producing proves that cementation intension and hydraulic sand washing are important factors which affect formation sanding production.Once the macroscopic throats forms in formation,water cut in well increases,and oil recovery reduces to 36 percent.The experiment results are useful for preventing sanding production in oilfield.

10.3969/j.issn.1000-7393.2005.05.018