胜利油区二元复合驱油先导试验驱油体系及方案优化研究

首先根据胜利油区的油藏特点和复合驱的特点,在孤东油田七区西南Ng54-61层优选出了具有广泛代表性的试验区。然后根据试验区具体的油藏情况,室内筛选出了适合该油藏类型的以石油磺酸盐为主剂的二元复合驱油体系,研究表明,该体系可与模拟油达到超低界面张力状态,其吸附量较小、乳化性能和热稳定性好,驱油效果好。结合室内研究的结果,在建立基于模糊综合评判模型的二元复合驱注采参数优化设计方法的基础上,对化学剂组合方式、配方浓度、段塞尺寸、注入方式、注采速度等参数进行了优化。综合研究认为,该二元复合驱油体系驱油效率高、油藏适应性强,可较大幅度提高采收率。

STUDY ON OIL FLOOD SYSTEM AND PLAN OPTIMIZATION IN THE PILOT TEST OF SURFACTANT/POLYMER FLOOD IN SHENGLI OIL FIELD

Coupling reservoir characteristic in Shengli oil field with surfactant/polymer flood peculiarity, pilot test area is selected in southwest Ng54-61 of District Seven in Gudong oil field. And surfactant/polymer flooding system is ascertained in experiment laboratory which is adaptable to this type of reservoirs. The main surfactant is petroleum sulfonate. This system possesses ultralow interfacial tension with the crude oil. Its adsorbance is little. Its emulsibility and thermal stability is fine. And its displacement efficiency is high. By numerical simulation, such parameters as combination manner of chemical agent, surfactant concentration, polymer concentration, slug size, injecting manner and injection rate are optimized. For the surfactant /polymer flooding system, its displacement efficiency is high. It has strong reservoir applicability and could enhance oil recovery greatly.