支化预交联凝胶颗粒微观驱油机理可视化实验

Visual experimental study on microscopic oil displacement mechanism of branched-preformed particle gel 

赵方剑 侯健 元福卿 王代刚 刘永革

中国石油大学（华东）石油工程学院，山东 青岛 266580 中国石化胜利油田分公司勘探开发研究院，山东 东营 257015 中国石油大学（北京）非常规油气科学技术研究院，北京 102249

由于良好的黏弹性、耐温抗盐性和悬浮性能，支化预交联凝胶颗粒（B￣PPG）作为驱油剂已广泛应用于三次采油领域。文中将B￣PPG岩心驱替实验与CT扫描技术相结合，研究了B￣PPG在真实岩心驱替过程中的微观驱油机理。实验结果表明：与水驱相比，驱替至残余油阶段，B￣PPG驱采收率提高了16.0百分点。基于CT扫描微观可视化研究，制定了剩余油赋存形态的划分标准，发现B￣PPG颗粒能以暂堵—变形—运移的方式从岩石表面剥离更多连片的剩余油，使剩余油呈现更低的接触面积比，驱替至残余油阶段时，形态复杂的多孔状剩余油成为主要赋存形态。

Because of good viscoelasticity, temperature resistance, salt resistance and suspension performance, branched-preformed particle gel (B-PPG) as oil displacement agents have been widely used in the tertiary oil recovery field. Combined the core displacement experiments of B-PPG with CT scanning technology in this paper, the microscopic oil displacement mechanism of B-PPG during the real core displacement process is studied. The experimental results show that compared with water flooding, B-PPG flooding recovery is increased by about 16.0 percentage points from displacement stage to residual oil stage. Based on the microscopic visualization study of CT scanning, classification standard of residual oil occurrence state is set. It is believed B-PPG can peel more contiguous residual oil from the rock surface in the way of temporary plugging, deformation and migration, which makes residual oil present a lower contact area ratio. The porous residual oil with complex shape after B-PPG flooding is main occurrence state from displacement stage to residual oil stage.

10.6056/dkyqt202204022