Flowback of proppant and formation sand often poses serious challenges to operating companies. These solids can cause equipment damage, costly and frequent cleanup treatments, and production decreases. Various mechanisms were found that destabilize the proppant pack, causing the proppant to produce back with the production fluid. Since 2005, curable resin systems for coating proppant on-the-fly during hydraulic fracturing completions and remedial proppant treatments of propped fractures have been applied in Argentina to provide an effective means for proppant flowback control and screenless completions in various basins.
Evaluation of these applications has helped determine that optimum concentrations of resin coatings on the proppant in either primary or remedial treatments are necessary to maximize the bonding between proppant grains to lock the grains in place while minimizing any reduction of the proppant pack conductivity. Additives included in the liquid resin systems permit good consolidation properties in the proppant pack, allowing it to effectively handle the shear forces of high production rates and multiphase flow and the effect of stress cycling as the well undergoes producing and being shut in.
Field results indicate that on-the-fly resin coating on proppant and remedial treatments effectively stops the proppant from producing back while allowing the well production rates to be maximized as designed. These processes have drastically decreased the number of solids cleanout workovers in the treated wells compared to the offset wells in the same field where resin treatments were not performed. These resin treatments provide a reliable and cost-effective alternative in marginal reservoirs, eliminating the need for sand screens and providing access to other intervals when deemed necessary without wellbore restrictions.