New anionic Gemini surfactant viscoelastic fluid for clean fracturing of natural gas hydrate

In this work, the properties of a new anionic Gemini surfactant (AGn) and its application in natural gas hydrate fracturing fluid are studied. The surface properties of AGn were investigated and the formulations of AGn / NH4Cl and AGn / TMBAC (Benzyltrimethylammonium chloride) systems were optimized. The temperature and shear resistance, shear recovery, viscoelasticity, and fracturing performance of the optimized system were evaluated. The results showed that AGn exhibits excellent surface activity and can spontaneously form worm-like micelles in aqueous solution. The optimized fracturing fluid system formulations were 1.5% AG16 + 0.4% NH4Cl and 1.5% AG16 + 0.4% TMBAC. The system had good rheological properties, outstanding filtration, and excellent sand suspension performance, and could complete gel breaking in a 4% NaCl environment. It was suggested that the AGn-based fracturing fluid system has the potential to meet the fracturing requirements of natural gas hydrate fracturing operations and has potential application prospects.