Petroleum Reservoir Evaluation and Development ›› 2024, Vol. 14 ›› Issue (1): 124-132.doi: 10.13809/j.cnki.cn32-1825/te.2024.01.017

• Comprehensive Research • Previous Articles     Next Articles

Development adjustment technology of extending life cycle for nearly-abandoned reservoirs

ZHANG Lianfeng1,2(),ZHANG Yilin1,2,GUO Huanhuan3,LI Hongsheng1,2,LI Junjie1,2,LIANG Limei1,2,LI Wenjing1,2,HU Shukui1,2   

  1. 1. Research Institute of Exploration and Development, Sinopec Henan Oilfield Company, Nanyang, Henan 473000, China
    2. Henan Provincial Key Laboratory of Enhanced Oil Recovery, Nanyang, Henan 473000, China
    3. Huabei Measurement and Control Company, Sinopec Jingwei Co, Ltd, Zhengzhou, Henan 450000, China
  • Received:2023-06-15 Online:2024-02-26 Published:2024-03-05


Facing the challenges of extremely high water cut, developed preferential channels, highly dispersed remaining oil, and strong heterogeneity in nearly abandoned reservoirs, the study focuses on the 4-5 layer series of the North Block II(Oil Group No. 2) in the Shuanghe Oilfield. By employing detailed reservoir geological modeling, numerical simulation methods, and microscopic displacement experiments, the distribution characteristics of remaining oil after polymer flooding were characterized. Post-polymer flooding, the remaining oil saturation is higher in areas away from the main streamlines on the macro scale, including non-mainstream areas, weak zones along main streamlines, and peripheral areas with larger injector-producer distances. Vertically, remaining oil tends to accumulate at the top of positive rhythm sequences. Microscopically, the remaining oil is primarily in the form of semi-bound state. Based on the characteristics of remaining oil distribution, a technical concept of heterogeneous composite driving and streamline well pattern densification adjustment was proposed. By adjusting the well pattern to alter streamlines, creating a staggered row and column well pattern with a change in streamline direction of over 30° and a streamline deflection rate of 80%, the effective mobilization of remaining oil is promoted. Numerical simulation predicts that this technique could increase the recovery factor by 10.96%, add 706.1 thousand tons of recoverable reserves, and extend the life cycle by 15 years. This offers a new technical approach for significantly enhancing the recovery factor of reservoirs after polymer flooding.

Key words: reservoir after polymer flooding, numerical simulation, remaining oil, encryption adjustment, heterogeneous composite flooding, enhanced oil recovery

CLC Number: 

  • TE319