预交联体增效聚合物驱研究

Study on Preformed Particle Gel (PPG)Enhanced Polymer Flooding

利用预交联体良好的耐温抗盐能力、在地层中具有变形特性和选择性进入等特点,首次开发建立了适合高温高盐和聚合物驱后提高采收率的预交联体增效聚合物驱油方法。室内高温高盐条件下双管驱油试验结果表明:预交联体增效聚合物驱油体系具有极好的液流转向、扩大波及体积能力,能够同时改善层内、层间矛盾;0.3PV聚合物驱比水驱提高采收率6.7%,而同等段塞尺寸的预交联体增效聚合物驱段塞提高采收率可达23.8%,聚合物驱后0.2PV预交联体增效聚合物驱段塞可进一步提高采收率11.8%。预交联体增效聚合物驱在高温高盐、聚合物驱后具有极好的提高采收率效果,是复杂苛刻油藏进一步提高采收率的潜力技术。

Preformed particle gel (PPG) enhanced polymer flooding is a new chemical flooding method which is suit to both serious heterogeneous reservoir and HT/HS reservoir based on PPG’s insensitive to temperature and salinity and excellent profile control performance. Two tube sand pack core flooding tests conducted under HT/HS reservoir condition of Shengli oilfield indicate that the injection of PPG enhanced polymer system generates a significant fluid diversion, tetrad the heterogenous both within layer and between layers, and improve the swept volume substantially. The incremented oil recovery by 0. 3Vp polymer flooding is only about 6.7% ,while the recovery ratio increase of PPG enhanced polymerflooding slug with the same volume is up to 23.8% ; 0.2Vp additional PPG enhanced polymer flooding slug can further increase oil recovery 11.8% after the polymer flooding. It can be predicted that PPG enhanced polymer flooding will meet a broad potential in HT/HS and post—polymer flooding reservoirs.