Effect of Ionic Strength on the Transport and Retention of Polyacrylamide Microspheres in Reservoir Water Shutoff Treatment
Effect of Ionic Strength on the Transport and Retention of Polyacrylamide Microspheres in Reservoir Water Shutoff Treatment
复制标题
离子强度对水库堵水处理中聚丙烯酰胺微球运移和滞留的影响
DOI：
10.1021/acs.iecr.7b01588
复制
发表时间：
2017-07-19
影响因子：
4.2
通讯作者：
Steenhuis, Tammo S.
中科院分区：
文献类型：
--
作者：
Yao, Chuanjin;Wang, Dan;Steenhuis, Tammo S.
了解离子强度（IS）对聚丙烯酰胺微球在多孔介质中迁移和滞留的影响，对于其在油藏堵水处理中的应用，特别是在高IS条件下的应用至关重要。本文在透明填砂微模型中进行了0.001 ~ 0.20M的不同IS值下的截留和释放实验，研究了聚丙烯酰胺微球在多孔介质中的孔尺度传输-截留-释放过程，以及它们在多孔介质中的截留机理和空间分布。采用DLVO相互作用剖面、小室剖分和质量平衡计算等方法，定量分析了IS在油藏堵水过程中对聚丙烯酰胺微球运移和滞留的影响。结果表明，聚丙烯酰胺微球的留着率随着IS的增加而增加，这是因为在高IS水平下能垒的减少/消除。在孔喉处的应变是所有IS条件下聚丙烯酰胺微球保留的最大贡献者。IS的减少有利于聚丙烯酰胺微球的释放，这些微球通过二次能量极小而松散地保留在砂粒表面。尽管如此，大部分释放的聚丙烯酰胺微球再次通过应变保留，这将进一步提高堵水性能。不可逆保留的初级能量最小值范围在0.37%和4.65%之间，随着IS的增加，消除高IS条件下的能量势垒可以增强这一过程。
Knowledge of the effects of ionic strength (IS) on the transport and retention of polyacrylamide microspheres in porous media is essential for their application in reservoir water shutoff treatment, especially under high-IS conditions. In this work, retention and release experiments were conducted in a transparent sand-packed micromodel at various IS values from 0.001 to 0.20 M to investigate the pore-scale transportretentionrelease processes of polyacrylamide microspheres, as well as their retention mechanisms and spatial distributions in porous media. DLVO interaction profiles, chamber dissections, and mass-balance calculations were used to quantitatively analyze the effects of IS on the transport and retention of polyacrylamide microspheres during reservoir water shutoff treatment. The results indicated that the retention of polyacrylamide microspheres increased with IS because of the diminution/elimination of the energy barrier at high IS levels. Straining at pore throats was the largest contributor to the retention of polyacrylamide microspheres for all IS conditions. IS reduction was beneficial to the release of polyacrylamide microspheres that were loosely retained on sand grain surfaces by secondary energy minima. Nevertheless, most of the released polyacrylamide microspheres were once again retained by straining, which would further enhance the water shutoff performance. Irreversible retention by primary energy minima ranged between 0.37% and 4.65% with increasing IS, and the elimination of the energy barrier under high-IS conditions could enhance this process.