海上油田高含水油藏水平井堵水实验研究

针对曹妃甸11-1油田油层的储层特性、非均质特征以及流体性质,评价了无机铬凝胶体系的成胶性能,通过调节聚合物和交联剂的加量,形成了一系列成胶时间可调、强度可控的配方;并考察了凝胶的黏弹性随时间的变化规律。借助水平井堵水物理模型模拟水平井堵水过程中堵剂的注入过程,评价了水平段地层平面非均质性对堵剂在水平井中渗流规律以及选择性封堵性能的影响。实验结果表明,无机铬凝胶体系的储能模量和耗能模量均随着交联反应时间的延长增大;当水平段跟部渗透率高,趾部渗透率低时,其选择性封堵性能要优于跟部渗透低趾部渗透率高时的选择性封堵性能。研究成果明确了堵剂在水平井中的渗流规律,为海上水平井堵水施工设计提供了技术支撑。

The experimental Study for Water Shut-off in Horizontal Well of High Water Cut Reservoir on Offshore Oilfield

According to the reservoir petrophysics, heterogeneity and fluid property in CFD11-1 oilfield, the gelation ability are evaluated for the inorganic chromium cross-linked polymer solution. A series of formula whose gelation time and strength can be controlled is formed by adjusting the amount of the polymer and the crosslinkder. At the same time, the viscoelasticity of the different crosslinking time of gel are measured. The injecting process of the plugging agent in the horizontal well is simulated by the horizontal well water shut-off physical model, and the impact of the plane heterogeneity of the horizontal section to the selectivity plugging and seepage laws is evaluated. The results indicated that the storage modulus and loss modulus rises with the crosslinking time. Compared with the low permeability of heel and high permeability of toe, the selective plugging is better than the inverse permeability distribution. The seepage laws of plugging agents is clear and technological foundation is provided for the water shut off in the horizontal well in offshore oilfield.