CDG/表面活性剂二元体系性能研究

Investigation on properties of CDG/surfactant combination system

针对温度70℃、矿化度20794mg/L的油藏,开展了胶态分散凝胶(CDG)/表面活性剂二元体系研究。研究了超支化聚合物浓度、聚交比对新型CDG成胶性能影响,结果表明聚合物浓度为800mg/L、聚交比为20∶1的CDG体系具有较好的成胶性能;扫描电镜实验表明CDG呈胶态分散结构;TGU装置测定CDG的转变压力,聚合物浓度为800mg/L、聚交比为20∶1体系成胶后形成CDG转变压力为52.4KPa。将CDG与表面活性剂SA复配后形成CDG/表面活性剂二元体系,与CDG相比其粘度增大、界面张力降低。岩心驱油实验表明:超支化聚合物浓度为800mg/L CDG与0.2%表面活性剂复配的二元体系的提高采收率程度比CDG提高采收率程度高6.58%。

On account of the reservoir whose temperature is 70℃ and salinity is 20794 mg / L,we carried out CDG / surfactant combination system and the study of the performance. The impact of gelling performance on different concentration of hyperbranched polymer and ratio of polymer to cross-linker are studied,the results show that the system which contains 800 mg / L polymer and a ratio of polymer to cross-linker of 20 ∶1 has good gelling performance,then the microstructure of CDG solution is decentralized in the way of scanning electron microscopy. Moreover,TGU device is used to detect the transition pressure of CDG solution,the transition pressure of gelled CDG solution which contains？ 800 mg / L polymer and a ratio of polymer to cross-linker of 20 ∶1 is 52. 4KPa. With the mixture of CDG and surfactant,the viscosity of the CDG / Surfactant combination is larger than that of CDG solution,and the interfacial tension will reduce. The core flooding tests show that the enhanced oil recovery of CDG / surfactant combiationn system which contains 800 mg / L hyperbranched polymer of CDG and 0. 2%surfactant SA is 6. 58%higher than that of CDG system.