Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas, United States of America.
Texas A&M Energy Institute, College Station, Texas, United States of America.
PLoS One. 2021 Dec 2;16(12):e0260786. doi: 10.1371/journal.pone.0260786. eCollection 2021.
Hydraulic fracturing of unconventional reservoirs has seen a boom in the last century, as a means to fulfill the growing energy demand in the world. The fracturing fluid used in the process plays a substantial role in determining the results. Hence, several research and development efforts have been geared towards developing more sustainable, efficient, and improved fracturing fluids. Herein, we present a dynamic binary complex (DBC) solution, with potential to be useful in the hydraulic fracturing domain. It has a supramolecular structure formed by the self-assembly of low molecular weight viscosifiers (LMWVs) oleic acid and diethylenetriamine into an elongated entangled network under alkaline conditions. With less than 2 wt% constituents dispersed in aqueous solution, a viscous gel that exhibits high viscosities even under shear was formed. Key features include responsiveness to pH and salinity, and a zero-shear viscosity that could be tuned by a factor of ~280 by changing the pH. Furthermore, its viscous properties were more pronounced in the presence of salt. Sand settling tests revealed its potential to hold up sand particles for extended periods of time. In conclusion, this DBC solution system has potential to be utilized as a smart salt-responsive, pH-switchable hydraulic fracturing fluid.
在上个世纪，非常规储层的水力压裂技术得到了蓬勃发展，成为满足世界不断增长的能源需求的一种手段。该过程中使用的压裂液在决定结果方面起着重要作用。因此，已经进行了多项研究和开发工作，旨在开发更可持续、高效和改进的压裂液。在这里，我们提出了一种动态双组分（DBC）溶液，它有可能在水力压裂领域得到应用。它具有超分子结构，由低分子量增稠剂（LMWV）油酸和二乙烯三胺在碱性条件下自组装成细长的缠结网络。不到 2wt%的成分分散在水溶液中，形成了一种粘性凝胶，即使在剪切下也具有很高的粘度。其关键特点包括对 pH 值和盐度的响应性，以及零剪切粘度可以通过改变 pH 值调节约 280 倍。此外，其粘性特性在存在盐的情况下更为明显。沙沉降测试表明，它有可能在很长一段时间内保持沙粒。总之，这种 DBC 溶液体系有潜力被用作一种智能的盐响应、pH 值可切换的水力压裂液。
