X-ray diffraction (XRD) is an important and widely used material characterization technique. With the recent development in material science technology and understanding, various new materials are being developed, which requires upgrading the existing analytical techniques such that emerging intricate problems can be solved. Although XRD is a well-established non-destructive technique, it still requires further improvements in its characterization capabilities, especially when dealing with complex mineral structures. The present review conducts comprehensive discussions on atomic crystal structure, XRD principle, its applications, uncertainty during XRD analysis, and required safety precautions. The future research directions, especially the use of artificial intelligence and machine learning tools, for improving the effectiveness and accuracy of the XRD technique, are discussed for mineral characterization. The topics covered include how XRD patterns can be utilized for a thorough understanding of the crystalline structure, size, and orientation, dislocation density, phase identification, quantification, and transformation, information about lattice parameters, residual stress, and strain, and thermal expansion coefficient of materials. All these important discussions on XRD analysis for mineral characterization are compiled in this comprehensive review, so that it can benefit specialists and engineers in the chemical, mining, iron, metallurgy, and steel industries. 

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X-ray Diffraction Techniques for Mineral Characterization: A Review for Engineers of the Fundamentals, Applications, and Research Directions

Wettability of sandstone rocks and their mineral components during CO2 injection in aquifers: Implications for fines migration

Effects of fines migration on oil displacement by low-salinity water

Imaging analysis of fines migration during water flow with salinity alteration.

Formation damage caused by fine migration and straining is a well-documented phenomenon in sandstone reservoirs. Fine migration and the associated permeability decline have been observed in various experimental studies, and this phenomenon has been broadly explained by the analysis of surface forces between fines and sand grains. The Derjaguin-Landau-Verwey-Overbeek (DLVO) theory is a useful tool to help understand and model the fine release, migration, and control phenomena within porous media by quantifying the total interaction energy of the fine-brine-rock (FBR) system. Fine migration is mainly caused by changes in the attractive and repulsive surface forces, which are triggered by mud invasion during drilling activity, the utilization of completion fluid, acidizing treatment, and water injection into the reservoir during secondary and tertiary recovery operations. Increasing pH and decreasing water salinity collectively affect the attractive and repulsive forces and, at a specific value of pH, and critical salt concentration (CSC), the total interaction energy of the FBR system (VT) shifts from negative to positive, indicating the initiation of fine release. Maintaining the system pH, setting the salinity above the CSC, tuning the ionic composition of injected water, and using nanoparticles (NPs) are practical options to control fine migration. DLVO modeling elucidates the total interaction energy between fines and sand grains based on the calculation of surface forces of the system. In this context, zeta potential is an important indicator of an increase or decrease in repulsive forces. Using available data, two correlations have been developed to calculate the zeta potential for sandstone reservoirs in high- and low-salinity environments and validated with experimental values. Based on surface force analysis, the CSC is predicted by the DLVO model; it is in close agreement with the experimental value from the literature. The critical pH value is also estimated for alkaline flooding. Model results confirm that the application of NPs and the presence of divalent ions increase the attractive force and help to mitigate the fine migration problem. Hence, a new insight into the analysis of quantified surface forces is presented in current research work by the practical application of the DLVO theory to model fine migration initiation under the influence of injection water chemistry.

Fine Migration Control in Sandstones: Surface Force Analysis and Application of DLVO Theory

Fines migration during supercritical CO2 injection in sandstone

Effect of water salinity on permeability alteration during CO₂ sequestration

Effect of fines migration and mineral reactions on CO2-water drainage relative permeability

\n Recent laboratory studies have shown that fines migration induces a decrease in rock permeability during CO2 injection. This study uses X–ray microcomputed tomography (micro–CT), nitrogen permeability, and Itrax X–ray fluorescence (Itrax–XRF) scanning to investigate the mechanism of fines migration during CO2 injection. We perform CO2–flooding experiments on two Berea core samples. The cores are characterized using nitrogen permeability, micro–CT, scanning electron microscopy with energy–dispersive X–ray spectroscopy (SEM–EDS), and Itrax–XRF scanning. The cores are flooded with fresh water, then CO2–saturated water, and finally water–saturated supercritical CO2 (scCO2). To calculate permeability, the pressure difference across the core samples is monitored during these fluid injections. The produced–water samples are analyzed using inductively coupled plasma–optical emission spectrometry (ICP–OES). After the flooding experiments, nitrogen permeability, micro–CT, SEM–EDS, and XRF scanning are repeated to characterize pore–scale damage. Micro–CT image–based computations are run to estimate permeability decrease along the core–sample length after injection.\n Results show the dissolution of dolomite and other high–density minerals. Mineral dissolution dislodges fines particles, which migrate during water-saturated–scCO2 injection. During CO2–saturated–water injection, the permeability of Berea 1 and Berea 2 increase by 29 and 13%, respectively. After water–saturated–scCO2 injection, the permeability of Berea 1 and Berea 2 decrease by 60%. The permeability damage of the sample can be explained by fines migration and subsequent blockage. SEM–EDS images also show instances of pore blockage.

Faisal Othman

Papers

Fines migration during supercritical CO2 injection in sandstone

Wettability of sandstone rocks and their mineral components during CO2 injection in aquifers: Implications for fines migration

Effect of water salinity on permeability alteration during CO₂ sequestration

Effect of fines migration and mineral reactions on CO2-water drainage relative permeability

The Effect of Fines Migration During CO 2 Injection Using Pore-Scale Characterization