考虑启动压力的低渗透油藏压裂改造井网优化

WELL PATTERN OPTIMIZATION FOR FRACTURING AND RECONSTRUCTION OF LOW-PERMEABILITY OIL RESERVOIR CONSIDERING THRESHOLD PRESSURE

大庆肇源油田属于低渗透油田，渗流规律偏离达西定律，往往表现出启动压力现象，流体渗流阻力大，油水井之间难于建立有效驱替系统。从人工裂缝走向出发，研究了适合大庆肇源低渗透油藏改造的井网类型和井排方向，确定了合理的井网密度和井距；考虑油藏各向异性强烈，优化了不同程度的渗透率各向异性所对应的最优井排距比，并绘制了相应的理论图板，这些研究成果可以为油田现场的井网部署提供参考依据。

Zhaoyuan Oilfield is a low-permeability oil field in Daqing, where the flow mechanism varies from Darcy law and threshold pressure always occurs. Due to the strong flow resistance, it is difficult to establish effective displacement system between injection wells and production wells. Based on the strikes of artificial fractures, well spacing pattern and well array directions suited to low-permeability reservoir reconstruction has been analyzed and reasonable well spacing density and distances between wells have been determined in Zhaoyuan Oilfield. Considering the severe anisotropy of the oil reservoir, optimum well spacing and well array ratio have been improved according to different degrees of anisotropic permeability; moreover, relevant theoretical charts have been generated. The conclusions from the studies will provide references for well pattern arrangement in the oilfield.