纳米纤维强化泡沫液膜渗透性及稳定性实验研究  

Experimental Study on Film Permeability and Stability of Nanofiber Enhanced Foam

作　　者：陈神根 王瑞 易勇刚 张鑫 徐金山 尚晋 CHEN Shengen;WANG Rui;YI Yonggang;ZHANG Xin;XU Jinshan;SHANG Jin(Research Institute of Engineering Technology,PetroChina Xinjiang Oilfield Company,Karamay 834000,Xinjiang,China)

机构地区：[1]中国石油新疆油田分公司工程技术研究院(监理公司),新疆克拉玛依834000

出　　处：《新疆石油天然气》2023年第1期81-88,共8页Xinjiang Oil & Gas

基　　金：中国石油天然气集团有限公司科研项目“CCUS注采工艺、产出气循环利用及高效防腐关键技术研究”(2021ZZ-01-04)。

摘　　要：泡沫可有效改善致密油藏气驱因气液流度差异、裂缝等造成的窜流问题,扩大气驱波及效率。但泡沫为热力学亚稳定体系,其长期稳定性受限制。基于纳米纤维(NCF)强化泡沫体系,对比分析其对N_(2)泡沫、CO_(2)泡沫中气体通过液膜渗透性影响,并观察两种NCF强化泡沫体系在不同含油条件下的微观形态变化,探讨了纳米纤维对泡沫稳定性的改善作用及泡沫体系稳定性与泡沫液膜渗透率的对应关系。研究发现,纳米纤维能有效降低液膜渗透性,0.1 wt%的NCF能使N_(2)气泡、CO_(2)气泡的渗透率分别降低约89%、65%,消泡时间分别提升2.7倍、11.3倍,表明纳米纤维通过降低液膜渗透性抑制了气泡失稳;经显微观察,NCF强化N_(2)泡沫液比CO_(2)泡沫初始膜厚度更大、泡沫直径更小,在不同含油条件下NCF强化CO_(2)泡沫的失稳趋势更强,表明NCF对N_(2)泡沫稳定性增强效果更佳。通过纳米纤维能改善泡沫性能,优化泡沫体系,从而增强泡沫稳定性,相关研究对提高油藏气驱采收率有一定的借鉴意义。Foam can effectively address the fluid channeling problem caused by gas-liquid mobility difference and fractures in gas flooding in tight reservoirs,and increase gas flooding sweep efficiency. However,the foam is a thermodynamically sub-stable system,and its long-term stability is limited. Therefore,based on the nanofiber(NCF)enhanced foam system,the influence of NCF on gas permeability through film in N_(2)foam and CO_(2)foam was analyzed,and the micromorphological changes of the two kinds of NCF enhanced foam system under different oil content were observed. Furthermore,the paper also explored how the nanofiber improves the foam stability and the relationship between the foam system stability and the permeability of the foam film. It was found the nanofiber can reduce the permeability of the film. The permeability of the N_(2)and CO_(2)bubbles was reduced by about 89% and 65% respectively by 0.1 wt % NCF,while the defoaming time was increased by 2.7 times and 11.3 times respectively. The results showed that NCF can inhibit bubble instability by reducing the permeability of the film,and the thickness of the NCF-enhanced N_(2)foam is higher than those of the CO_(2)foam,while the diameter of the NCF-enhanced N_(2)foam is smaller. The instability trend of NCF enhanced CO_(2)foam is stronger under different oil content,which shows that NCF can enhance the stability of N_(2)foam better. The nanofiber can be used to improve the foam performance,optimize foam system,thus enhancing foam stability. Research in this field has proved to be helpful for improving the recovery factor of gas flooding reservoirs.

关 键 词：纳米纤维 N_(2)/CO_(2)泡沫 液膜渗透性 泡沫稳定性 含油条件 

分 类 号：TE357.46[石油与天然气工程—油气田开发工程]