Evaluation of Preformed Particle Gels Penetration into Matrix for a Conformance Control Treatment in Partially Open Conduits

摘要

Preformed particle gels (PPGs) serve as a conformance control agent and have been used widely to control excess water production through conduits, fractures or fracture-like features. This paper ranks the parameters that impact PPG resistance to water flow in partially opened conduits and provides methods to minimize PPG penetration effect on matrices. Experiments were conducted to examine the effect of brine concentration, PPG injection pressure, back pressure, and matrix permeability on PPG resistance to water flow through conduits and PPG penetration to matrix. PPGs were swelled in different concentration brines and were injected into the conduits at a few designed injection pressures. Results show PPG resistance to water flow may have been the result of gel particle accumulation into conduits or gel filter cake formation in rock matrix or both. Their resistance increased when they were injected at high pressure. In contrast to PPGs placement through fully opened conduits, PPGs were not produced from the partially opened conduits; however, PPGs formed a filter cake on the surface of the matrix. Gel particles penetration into the matrix were only a few millimeters deep, and their penetration into to the matrix depended on matrix permeability, gel strength, and injection pressure drop across the core.