Using Properties in Nature to Modify Proppant Surfaces and Increase Flow

Abstract

Abstract In oil and gas wells that are hydraulically fractured, wetting properties of surfaces (formation and proppant) significantly affect hydrocarbon and liquid displacement. During the life of a well, the water saturation of surfaces changes, leading to reduction of relative permeability to oil or gas and consequently affecting production. In order to reverse the formation to a reduced water wet state and improve the movement of hydrocarbons, strong water-wet surfactant is pumped. The surfactant is then adsorbed onto the surfaces reducing the capillary pressure and water saturation within the porous systems. This is, however, not a permanent solution, as the surfactant is washed out over time. A more permanent and robust solution is needed. Nature encompasses many examples of biological systems and surfaces that are permanent and have special wettability and interfacial interaction with fluids. Research and development within the last decade in bio-mimicking nature has been fruitful and led to the development of many new surfaces such as superhydrophobic, ice phobic and low-drag surfaces. In this work we apply some of the knowledge and principles found in nature to modify proppant surfaces (silica sand and ceramic proppant) in order to study how wettability will affect the fluids recovery and their interaction with the solid surfaces. Nanotechnology was used to deposit hydrophobic/oleophobic moieties onto the proppant surfaces, and several surface modifiers were tested. These molecules were covalently bonded to the surfaces. The new surfaces were characterized for wettability and flow to water and oil. A new proppant that show promises for improved stimulation fluids recovery and flow was identified and further developed.