Application of gemini viscoelastic surfactant with high salt in brine-based fracturing fluid

摘要

In this study, a viscoelastic surfactant (VES), named VES-Q, with erucyl amide tails and cyclodextrin was successfully synthesized, and the phase behavior of aqueous VES solutions at different salt concentrations was observed. In addition, the size of the molecules under different salt types was measured using dynamic light scattering. The viscosity of VES-Q in salt solution corresponds to the molecular size of the surfactant was found. Due to the high salinity tolerance of VES-Q to common formation salts, we used formation water from West Sichuan and seawater the Gulf of Mexico to allocate VES-Q to two clean fracturing fluids, namely, fluid 1 and fluid 2, with a concentration of 2%. Rheological properties under high-temperature reservoir conditions were simulated. The clean fracturing fluid was prepared by the VES-Q method, and its performance met the requirements of hydraulic fracturing operations.