Organic-rich shales in the last decade have become a focus of the oil and gas industry, and currently are the primary source of oil and gas production from Unconventional resources. These resources will be in need of a method of enhanced recovery to maximize lifetime production from each well. Spontaneous imbibition, or the adsorption of a fluid into a porous media due to capillary forces and consequent displacement of non-wetting fluids is a good potential enhanced recovery method. Measuring the amount of spontaneous imbibition in an organic-rich shale is complicated by several challenges compared to traditional oil reservoir rocks, such as the ultra-low permeability and the high clay content. This clay content can often lead to swelling, which can affect imbibition measurements. In this study, a new gravimetric method for measuring spontaneous imbibition is developed that can measure the rate, and volume of spontaneous imbibition as well as the degree of shale swelling. Two organic-rich shales, the Bakken and the Utica were examined and compared to establish the viability of the experimental method. The results of this work suggest that this method is a promising and viable method for measuring the volume and rate of spontaneous imbibition in organic-rich shale. The exposure of organic-rich shales to atmospheric conditions can significantly modify the properties of the shale through drying or hydration of the samples. All of the shales used in experiments in the following study were carefully maintained at their native state before exposure to the imbibition fluids. Additionally, the shale samples were exposed to several surfactant mixtures to measure the effect of these surfactants on the rate of imbibition.

Massive hydraulic fracturing operations conducted in shale reservoirs create extensive fracture networks to enhance recovery of hydrocarbons from low permeability shale reservoirs. Fluid invasion into the shale matrix is identified as one of the possible mechanisms leading to low fracturing fluid recovery after the fracturing operations. Studying the mechanisms of liquid imbibition into shale matrix is essential for understanding the fate of non-recovered fracturing fluid that can eventually lead to better utilization of water resources by reducing cost and environmental impact. This study aims to investigate effects of base fluid type (aqueous vs. oleic phase), polymer enhanced viscosity, salinity and surfactants in aqueous solutions on the imbibition rate in actual shale samples. The shale samples were collected from Fort Simpson, Muskwa and Otter Park formations, all belong to greater Horn River Basin. The samples were characterised by measuring porosity, wettability (through contact angle measurements), mineralogy (through XRD analysis), TOC, and interpreting wire line log data. We find that imbibition rate of aqueous phase is higher than that of oleic phase. Moreover, we find that imbibition rates of KCl brine, surfactants and viscous polymer solutions are lower than that of fresh water. We find that dimensionless time used to model spontaneous imbibition in conventional rocks requires specific adjustments for application in shales. Based on applied upscaling method, it was found that spontaneous imbibition can cause significant water loss at the field scale during shut-in period after hydraulic fracturing.

Fluid-Solid Interactions in Upstream Oil and Gas Applications, Volume 78 delivers comprehensive understanding of fluid-rock interactions in oil and gas reservoirs and their impact on drilling, production, and reservoir hydrocarbon management. The book is arranged based on intervals of the oil and gas production process and introduces the basics of reservoir fluids and their properties, along with the rheological behavior of solid-fluid systems across all stages of the reservoir, including drilling processes, acidizing, and fracking. The reference then addresses different application-specific issues, such as solid-fluid interactions in tight reservoirs, the applications of nanoparticles, interactions during the EOR processes, and environmental concerns. Introduces the basics of reservoir fluids and their properties as well as the rheological behavior of solid-fluid systems Discusses the latest advances in molecular simulations and their reliability Highlights the environmental concerns regarding the application of fluid-solid systems

Atoms and molecules in all states of matter are subject to continuous irregular movement. This process, referred to as diffusion, is among the most general and basic phenomena in nature and determines the performance of many technological processes. This book provides an introduction to the fascinating world of diffusion in microporous solids. Jointly written by three well-known researchers in this field, it presents a coherent treatise, rather than a compilation of separate review articles, covering the theoretical fundamentals, molecular modeling, experimental observation and technical applications. Based on the book Diffusion in Zeolites and other Microporous Solids, originally published in 1992, it illustrates the remarkable speed with which this field has developed since that time. Specific topics include: new families of nanoporous materials, micro-imaging and single-particle tracking, direct monitoring of transient profiles by interference microscopy, single-file diffusion and new approaches to molecular modeling.

Petrophysical Characterization and Fluids Transport in Unconventional Reservoirs presents a comprehensive look at these new methods and technologies for the petrophysical characterization of unconventional reservoirs, including recent theoretical advances and modeling on fluids transport in unconventional reservoirs. The book is a valuable tool for geoscientists and engineers working in academia and industry. Many novel technologies and approaches, including petrophysics, multi-scale modelling, rock reconstruction and upscaling approaches are discussed, along with the challenge of the development of unconventional reservoirs and the mechanism of multi-phase/multi-scale flow and transport in these structures. Includes both practical and theoretical research for the characterization of unconventional reservoirs Covers the basic approaches and mechanisms for enhanced recovery techniques in unconventional reservoirs Presents the latest research in the fluid transport processes in unconventional reservoirs