测定聚合物或交联聚合物不可及孔隙体积新方法

New Method for Determination of Inaccessible Pore Volume of Polymer or Crosslinking Polymer

马云飞 侯吉瑞

MAYunfei HOU Jirui

聚合物不可及孔隙体积（IPV）对聚合物驱波及系数的影响较大，为了尽可能从配方优选的角度减弱这一参数的负面影响，建立了一种测试IPV 的新方法。该方法采用淀粉-碘化镉法测量通过岩心孔隙的聚合物浓度，结合质量守恒公式，直接计算聚合物对于岩心的IPV，并借助压汞数据所得的岩心孔隙半径与频率分布关系，推算出不可及孔隙极限半径。用该方法计算了部分水解聚丙烯酰胺和交联聚合物溶液的IPV 与不可及孔隙极限半径，研究了岩心渗透率和交联剂浓度对这两个参数的影响。实验结果表明，随着岩心渗透率下降，聚合物溶液IPV逐渐增大；岩心渗透率相近时，交联剂浓度越高，不可及孔隙体积百分比越大。在渗透率较高的岩心中，交联聚合物的不可及孔隙极限半径随交联剂浓度增加而增大；在渗透率较低的岩心中，交联剂浓度对聚合物溶液的不可及孔隙极限半径几乎没有影响。该方法具有操作简便、结果可靠的特点，可以通过采集得到的露头岩心测量任意油层的IPV和不可及孔隙极限半径，并对聚合物或交联聚合物的配方优选提供数据支持。图3 表3 参19

Inaccessible pore volume（IPV）of polymer had a deep impact on the swept volume in polymer flooding. In order to reduce the effect of IPV as much as possible in consideration of formula optimization，a new method for the measurement of IPV was built. Starch-cadmium iodide method was used to measure the concentration of polymer through the cores，then the IPV could be calculated directly with the equation of mass conservation. Besides，with the distribution of pore radius by mercury intrusion method，the limit radius of IPV could be calculated. With this method，the IPV and the limit radius of IPV of HPAM and crosslinking HPAM solution were calculated，and on this basis，the effect of permeability and crosslinking agent dosage on the two parameters was studied. The results showed that the IPV increased with decreasing permeability，and the ratio of IPV increased with increasing concentration of crosslinking agent when the permeability was similar. The limit radius of IPV enlarged with increasing dosage of crosslinking agent in the core with high permeability. However，the dosage of crosslinking agent barely affectd the limit radius of IPV when the permeability was lowered to a certain extend. The method was simple and reliable. The IPV and the limit radius of IPV of any oil layer could be measured as long as the outcrop cores were obtained. The result of the study could provide data support on the formula optimization of polymer or crosslinking polymer flooding.

10.19346/j.cnki.1000-4092.2017.02.033