High-Temperature and Salt-Resistant Self-Suspending Proppant for Hydraulic Fracturing

In recent years, new technologies involving self-suspending proppant (SSP), which improves proppant distribution, reduces the use of chemicals in fracturing fluids, and simplifies the fracturing construction process, have become a focus of hydraulic fracturing research. However, the available products have poor suspension stability, cannot withstand high temperature and salt environments, and are highly damaging to reservoirs. In this study, we presented a novel self-suspending (HTS-SSP) proppant with excellent suspension stability, temperature resistance, and salt resistance, prepared from quartz sand, silane coupling agent, and modified polyacrylamide to achieve these properties. Wettability tests, surface morphology analysis, and Fourier transform infrared spectroscopy analysis proved that 3-methacryloxypropyltrmethoxysilane (KH570) successfully modifies quartz sand, and the HTS-SSP was synthesized. In terms of the suspension performance, HTS-SSP exhibited exceptional suspension stability due to the incorporation of KH570. It remained suspended at 150 °C or 24 wt % brine and showed excellent temperature and salt resistance. The gel-breaking fluid of the surface polymer of HTS-SSP had low damage to the reservoir, much less than the guar gum fluid. The difference between the conductivity of the aggregate remaining after HTS-SSP gel-breaking and that of unmodified quartz sand was not significant. The synthesized HTS-SSP demonstrates outstanding comprehensive performance and is an ideal candidate for reservoir development under harsh temperature and salinity conditions.