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Characterization of fluid–rock interactions is essential for a broad range of subsurface applications such as understanding fluid flow in porous medium and enhanced oil recovery predictions. Enhanced oil recovery (EOR) is crucial in oil and gas production operations, it entails injecting fluids into the reservoir to enhance productivity. When fluids are injected, interactions occur between the injected fluids and the reservoir rock/fluids; and the outcomes of fluid–rock interactions critically impact the fluid flow in porous medium and the associated oil recovery. Furthermore, the associated changes in reservoir properties (porosity, permeability etc.) and flow behavior (i.e. wettability alteration and relative permeability changes) demonstrate variability at a range of scales. Thus, it is of great importance to understand these interactions at multiple scales and their ensuing implications on EOR. This study therefore provides a comprehensive review of the types of fluid–rock interactions in both carbonate and sandstone reservoirs. Fluid–rock interactions quantification methods, their applicability and principle of measurements were summarized. The implications of fluid–rock​ interactions were extensively discussed. Finally, we identified and highlighted some research gaps and provided recommendations for future research directions.The findings of this review show that despite numerous studies on fluid–rock interactions such as adsorption, dissolution/precipitation, clay swelling/fines migration and wetting characteristics in porous media involving EOR fluids, the exact mechanism of action of these fluids during EOR applications in rock/oil/brine system, is still not fully understood. The extent and implications of these fluid–rock interactions on EOR depends on several factors/parameters. Such factors include the injected fluid type and chemical composition, rock type and mineralogical composition, brine pH, salinity and composition. Moreover, the review shows that all the fluid–rock interactions quantification techniques have some limitations either in their applicability, measurement range, or uncertainty level. Therefore, the incorporation of various imaging and characterization tools would be required for improved understanding the fluid–rock interactions.The review, therefore, provides critical insights in the area of fluid–rock interactions and its implications on EOR. Thus, the findings of this review are expected to enhance our knowledge and provide better understanding of fluid–rock interactions and thereby reduce the uncertainties associated with laboratory-scale predictions, reservoir management and enhanced recovery of oil.

With the increasing global population, fossil fuel resources still represent a main contributor to the energy supply, despite the progress made in the field of renewable energies. Large quantities of residual oil from mature reservoirs cannot be produced through primary and secondary recovery methods. Among alternative recovery techniques, chemically enhanced oil recovery methods are attracting considerable interest to increase the hydrocarbon recovery from oil-bearing geological formations. The wettability of any particular formation can be used to predict the oil recovery factor of a reservoir based on its wetting state. However, due to the complex nature of geological porous media, special treatments are required to control the wetting characteristics for improving the oil recovery. In this work, methyl orange (MO), a hazardous pollutant widely discharged in industrial wastewater, was used as a chemical agent for the purpose of altering the wettability. Initially, quartz substrates were aged with 10−2mol/L n-decane/stearic acid solution to mimic natural geological conditions; then, stearic acid-aged quartz substrates were treated in various concentrations of MO (10, 25, 50, 75, and 100 mg/L) for 7 days at 50 °C, followed by advancing and receding contact angle measurements at various physico-thermal geological conditions (temperature 25, 50 °C, pressure 10, 15, 20 MPa, and brine salinity 0–0.3 M). Our results demonstrate that increasing the temperature, pressure, and salinity of quartz aged with stearic acid has a negative effect on the wettability (resulting in a higher hydrophobicity). However, at any constant physio-thermal condition, MO significantly alters the wettability of the organic-aged quartz substrates from oil-wet to water-wet conditions, thus improving oil recovery. The concentration of MO plays a critical role, with increasing concentrations favouring the water-wet conditions. Quartz aged with MO at a concentration of 100 mg/L shows water-wet behaviour, with the lowest advancing and receding contact angles of 31° and 29°, respectively, at 25 °C, 20 MPa, and 0.3 M salinity. The findings of this study provide new insights that can be useful for disposing MO in deep underground reservoirs rather than discharging into the hydrosphere, thus mitigating climate change. In addition, the present data can be helpful for improving the oil productivity from sandstone reservoirs.

The article proposes a methodology for optimizing the process of irrigation of crops using a phytoindication system based on computer vision methods. We have proposed an algorithm and developed a system for obtaining a map of irrigation for maize in low latency mode. The system can be installed on a center pivot irrigation and consists of 8 IP cameras connected to a DVR connected to a laptop. The algorithm consists of three stages. Image preprocessing stage - applying an integrated excess green and excess red difference (ExGR) index. The classification stage is the application of the method that we choose depending on the system’s operating conditions. At the final stage, a neural network trained using the Resilient Propagation method is used, which determines the rate of watering of plants in the current sector of the location of the sprinkler. The selected methods of pretreatment and classification made it possible to achieve an accuracy of plant identification up to 93%, growth stages - up to 92% (with unconsolidated maize sowing and good lighting). System performance up to 100 plants in one second, which exceeds the performance of similar systems. The neural network showed an accuracy of 92% on the training set and 87% on the test set. Dynamic analysis of spatial and temporal variability leads to an increase in productivity and efficiency of water use. In addition, given the ubiquitous distribution of agribusiness management systems, this approach is quite simple to implement in the farm’s conditions.

Hydrogen (H2) as a cleaner fuel has been suggested as a viable method of achieving the de-carbonization objectives and meeting increasing global energy demand. However, successful implementation of a full-scale hydrogen economy requires large-scale hydrogen storage (as hydrogen is highly compressible). A potential solution to this challenge is injecting hydrogen into geologic formations from where it can be withdrawn again at later stages for utilization purposes. The geo-storage capacity of a porous formation is a function of its wetting characteristics, which strongly influence residual saturations, fluid flow, rate of injection, rate of withdrawal, and containment security. However, literature severely lacks information on hydrogen wettability in realistic geological and caprock formations, which contain organic matter (due to the prevailing reducing atmosphere). We, therefore, measured advancing (θa) and receding (θr) contact angles of mica substrates at various representative thermo-physical conditions (pressures 0.1-25 MPa, temperatures 308–343 K, and stearic acid concentrations of 10−9 - 10−2 mol/L). The mica exhibited an increasing tendency to become weakly water-wet at higher temperatures, lower pressures, and very low stearic acid concentration. However, it turned intermediate-wet at higher pressures, lower temperatures, and increasing stearic acid concentrations. The study suggests that the structural H2trapping capacities in geological formations and sealing potentials of caprock highly depend on the specific thermo-physical condition. Thus, this novel data provides a significant advancement in literature and will aid in the implementation of hydrogen geo-storage at an industrial scale.

Tight hydrocarbon reservoirs require stimulation to improve the recovery of oil and gas resources. Hydraulic fracturing is a technique extensively employed in the oil and gas industry to generate fractures including primary and secondary fractures. To keep these fractures open, proppants are used. However, some of these ractures are very narrow for conventional proppants to penetrate and prop, hence smaller proppants called micro-proppants are required. These micro-proppants can improve the hydraulic conductivity of both, the primary fractures and the untouched microfractures, leading to enhanced oil and gas recovery.This paper presents a critical review on the progress of current micro-proppants models, technologies and field applications (sub 100˗mesh proppants) with a particular attention to micro-proppants placement in hydraulic and natural fractures. The impact of various factors on micro-proppant placement in the fractures is analyzed. These factors include proppant concentration (i.e., volume fraction of solid proppant), proppant size, fracturing fluid chemistry, and confining stress (causing proppant deformation and proppant embedment into the rock). This review concludes that using micro-proppants can improve the efficiency of the hydraulic fracturing treatment, leading to enhanced oil and gas production.