PDF(Pubmed)
Abstract：
Gel treatment is an economical and efficient method of controlling excessive water production. The gelation of in situ gels is prone to being affected by the dilution of formation water, chromatographic during the transportation process, and thus controlling the gelation time and penetration depth is a challenging task. Therefore, a novel gel system termed preformed particle gels (PPGs) has been developed to overcome the drawbacks of in situ gels. PPGs are superabsorbent polymer gels which can swell but not dissolve in brines. Typically, PPGs are a granular gels formed based on the crosslinking of polyacrylamide, characterized by controllable particle size and strength. This work summarizes the application scenarios of PPGs and elucidates their plugging mechanisms. Additionally, several newly developed PPG systems such as high-temperature-resistant PPGs, re-crosslinkable PPGs, and delayed-swelling PPGs are also covered. This research indicates that PPGs can selectively block the formation of fractures or high-permeability channels. The performance of the novel modified PPGs was superior to in situ gels in harsh environments. Lastly, we outlined recommended improvements for the novel PPGs and suggested future research directions.
摘要：
凝胶处理是控制过量水产生的经济有效的方法。原位凝胶的凝胶化容易受到地层水稀释的影响，在运输过程中色谱，因此控制凝胶化时间和穿透深度是一项具有挑战性的任务。因此,已经开发了一种称为预成型颗粒凝胶(PPGs)的新型凝胶系统来克服原位凝胶的缺点。PPG是超吸收聚合物凝胶,其可以溶胀但不溶解在盐水中。通常,PPGs是基于聚丙烯酰胺交联形成的颗粒状凝胶，具有可控的粒度和强度。这项工作总结了PPG的应用场景，并阐明了它们的封堵机制。此外,几个新开发的PPG系统，如耐高温PPG，可重新交联的PPGs，和延迟肿胀的PPG也被覆盖。这项研究表明，PPG可以选择性地阻断裂缝或高渗透通道的形成。新型改性PPG的性能在恶劣环境中优于原位凝胶。最后,我们概述了新型PPG的建议改进方案,并提出了未来的研究方向.
