Property Evaluation and Field Applications of a New Self-Suspending Proppant

When conventional guar fracturing fluid is used for fracturing, low-permeability reservoirs are significantly damaged by its residues, the flow chart of fluid preparation is complex and the operation intensity is high. In order to solve these problems, a self-suspending proppant was prepared with coated quartz sand as the core and swelling resin as the suspending material. Later, its properties were evaluated and riverfrac tests were carried out on it. Laboratory property evaluation results demonstrated that the self-suspending proppant was equivalent to ceramic and coated quartz sand in terms of physical and chemical properties and to coated quartz sand in terms of flow conductivity. Suspension state appeared within 140 s and no stratification occurred at 110℃ after it was rested for 120 min. It was stable for 27 min after being shorn for 10 min at the shear rate of 540 s-1, and its viscosity after break was only 4 mPa·s. This self-suspending proppant was applied in 6 wells for riverfrac with success rate of 100%. Obviously, it reached the technical indictors of domestic sand fracturing with conventional gel fracturing fluid. It was shown that the self-suspending proppant could meet the operation requirements of riverfrac. Based on results, guar consumption was reduced, the flow chart of fluid preparation was simplified and reservoir damage was mitigated. Therefore, applying the new approach could result in better economic returns.