Applying deep bed filtration theory to study long-term impairment of fracture conductivity caused by reservoir fines

Abstract

This paper examines conductivity/permeability impairment of hydraulically-created fractures owing to intrusion of reservoir fine particle. The blockage of fracture network by the reservoir fines will cause productivity loss. Understanding the mechanism upon which the fracture conductivity is reduced owing to intrusion of reservoir fines is essential for operation design and accurate prediction of stimulation performance in reservoirs with unconsolidated sand pockets.In this study, the deep bed filtration network model is used to study transport and distribution of the intruded reservoir particles into a propped fracture plane. The fracture plane was discretized into a series of flow bed elements/units wherein transportation and distribution of particles and capturing coefficient were determined. The bilinear flow model was adopted to explain particulate flow transport into the fracture plane from disrupted sand pockets.An experimental approach was further used to validate the model predictions. A sensitivity analysis was performed to study impacts of proppant size, production/flow rates, fluid viscosity, and the fracture length on the long-term fracture conductivity damage caused by intrusion of reservoir fines. It is anticipated that the approach presented in this paper can immensely contribute to development of a computationally viable method to study productivity impairment due to fines migration and selection of candidate wells for refracturing operation.