Luo Dan, Wang Feng, Zhu Jingyi, Cao Feng, Liu Yuan, Li Xiaogang, Willson Richard C, Yang Zhaozhong, Chu Ching-Wu, Ren Zhifeng
Department of Physics and Texas Center for Superconductivity, University of Houston, Houston, TX 77204; Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX 77204; State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan 610500, China;
Department of Physics and Texas Center for Superconductivity, University of Houston, Houston, TX 77204;
Proc Natl Acad Sci U S A. 2016 Jul 12;113(28):7711-6. doi: 10.1073/pnas.1608135113. Epub 2016 Jun 27.
The current simple nanofluid flooding method for tertiary or enhanced oil recovery is inefficient, especially when used with low nanoparticle concentration. We have designed and produced a nanofluid of graphene-based amphiphilic nanosheets that is very effective at low concentration. Our nanosheets spontaneously approached the oil-water interface and reduced the interfacial tension in a saline environment (4 wt % NaCl and 1 wt % CaCl2), regardless of the solid surface wettability. A climbing film appeared and grew at moderate hydrodynamic condition to encapsulate the oil phase. With strong hydrodynamic power input, a solid-like interfacial film formed and was able to return to its original form even after being seriously disturbed. The film rapidly separated oil and water phases for slug-like oil displacement. The unique behavior of our nanosheet nanofluid tripled the best performance of conventional nanofluid flooding methods under similar conditions.
当前用于三次采油或强化采油的简单纳米流体驱油方法效率低下，尤其是在纳米颗粒浓度较低时使用。我们设计并制备了一种基于石墨烯的两亲性纳米片纳米流体，其在低浓度下非常有效。我们的纳米片会自发地靠近油水界面，并在盐水环境（4 wt% NaCl和1 wt% CaCl2）中降低界面张力，而与固体表面润湿性无关。在适度的流体动力学条件下会出现并生长出攀爬膜以包裹油相。在强大的流体动力输入下，会形成类似固体的界面膜，即使在受到严重干扰后也能恢复到其原始形态。该膜能快速分离油相和水相，实现段塞状驱油。在相似条件下，我们的纳米片纳米流体的独特性能使传统纳米流体驱油方法的最佳性能提高了两倍。
