聚合物传输运移能力和油藏适应性评价

Evaluation of Polymer Transmission and Migration Capacity and Reservoir Adaptability

苏延昌

SU Yanchang

大庆太18-38 井区具有储层渗透率低和非均质性强的特点，水驱开发效果受到极大影响，亟待采取进一步 提高采收率技术措施。针对大庆太北开发区的问题，开展了普通聚合物和抗盐聚合物溶液渗流特性和传输运移 能力实验研究和作用机理分析。结果表明，与普通聚合物相比，抗盐聚合物分子聚集体尺寸较大，岩心孔隙内尤 其是注入端附近区域内的滞留水平较高，致使该区域渗流阻力增幅以及压差和压差比较大，传输运移能力较 差。与普通聚合物不同，抗盐聚合物分子链上存在少量片状结构，致使聚合物分子链间缠绕作用增强、分子聚集 体尺寸增大和聚合物传输运移能力变差。当目标油藏储层渗透率为238×10-3、246×10-3、255×10-3 μm2时，与其相 适应的聚合物分别为中分、中高分、高分聚合物；当储层渗透率为500×10-3 μm2时，适应的聚合物为超高分和抗盐 聚合物。

Tai 18-38 well area in Daqing has the characteristics of low reservoir permeability and strong heterogeneity，as a result， the development effect of water flooding is greatly affected，and thus further technical measures to enhance oil recovery are urgently needed. Aiming at the problems in Taibei Development Zone of Daqing，the experiment research and mechanism analysis of the seepage characteristic and transmission capacity of common polymer and salt-resistant polymer solution were carried out. The results showed that compared with ordinary polymer，salt-resistant polymer had larger molecular aggregate. The retention level in the core pores，especially in the area near the injection end，was high. As a result，the increase of seepage resistance，pressure difference and differential pressure ratio in this area were relatively large. The transmission and migration capacity was poor. Unlike ordinary polymer，salt-resistant polymer had a small amount of flaky structures on its molecular chains. So the entanglement between polymer chains was enhanced，the size of molecular aggregate was increased，then the transmission and migration capacity of polymer was poor. When the permeability of target reservoir was 238×10-3，246×10-3 and 255×10-3 μm2，the corresponding polymer was medium，medium and high score polymer，and high score polymer，respectively. When the reservoir permeability was 500×10-3 μm2，the suitable polymer was super high score and salt-resistant polymer.

10.19346/j.cnki.1000-4092.2022.04.017