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Chemical storage of hydrogen, originated from renewable energy, is one of the most efficient and reliable methods to absorb carbon dioxide (CO2) and easily transport large-scale energy to remote areas. In this study, a novel integration of an electro-thermochemical process with industrial flue gas thermal energy and wind turbines is proposed to absorb CO2and store chemically hydrogen in the form of methanol, formic acid, and ammonium bicarbonate. The proposed hybrid structure includes a post-combustion CO2capture technology, a copper–chlorine thermochemical process, and several ammonium bicarbonate, formic acid, and methanol production cycles. The proposed configuration produces 2597 kg/h methanol, 5270 kg/h ammonium bicarbonate, and 833.3 kg/h formic acid. The energy and exergy efficiencies of the proposed layout are computed at 63.68 and 66.82%, respectively. The exergy analysis depicts that three processes of electro-thermochemical, methanol production, and post-combustion CO2capture have the greatest destructed exergy contributions among other subsections to the amounts of 40.85, 30.16, and 7.97%, respectively. The verification, validation, and sensitivity analyses, along with a multi-objective optimization protocol (i.e., a hybrid neural network and a genetic algorithm), are also used to evaluate the proposed system. The objective functions, decision variables, and constraints for the optimization phase are determined through sensitivity analysis. Several multi-criteria decision evaluation methods are employed to prioritize and choose the optimal point from the Pareto set. The electrical power supplied from the wind turbines as well as the auxiliary power supply, and the energy and exergy efficiencies calculated based on the TOPSIS/LINAMP techniques are 9.90 MW, 89.23, and 67.27%, respectively. In addition, the power consumption, energy, and exergy efficiencies at the optimal operating condition, calculated using the Bellman–Zadeh approach, are 9.673 MW, 83.26, and 67.19%, respectively.

Naturally fractured reservoirs (NFRs) contain a significant amount of the world’s oil reserves. Oil recovery by gravity drainage in a NFR strongly depends on the capillary height of the porous medium. Capillarity and gravity forces are usually the major driving forces in NFRs. To address this issue, a series of flow visualization experiments were performed using unconsolidated packed models of rectangular geometry with two fractures on the side. Parametric sensitivity analyses were performed considering effects of different system parameters such as fracture aperture, matrix height and permeability, and fluid viscosity on liquid drainage rate. These experiments enabled us to capture some aspects of the flow communication between matrix block and fracture during gravity drainage. Results from this study showed that the rate of liquid flowing from matrix to fracture is proportional to the difference of liquid levels in the matrix and in the fracture (Hf– Hm). In addition, the characteristic rate and the maximum liquid drainage rate from these fractured models are determined for stable gravity-dominated processes. Also, it was concluded that the characteristic rate depends only on the dimensions of the fracture and properties of the test fluid, and not on the properties of the matrix. For a given fracture–matrix system with different initial liquid saturation conditions, it is observed that the production history can be correlated by plotting the fraction of recoverable liquid as a function of time. Furthermore, ultimate recovery factor and capillary threshold height can be correlated using dimensionless numbers such as the Bond number and the porosity ratio.

Choosing an effective chemical inhibitor to prevent asphaltene precipitation and deposition in oil reservoirs is crucial for flow assurance management in the oil industry. Traditional laboratory screening methods are time-consuming and expensive. Therefore, we propose an alternative, which is employing molecular dynamics (MD) simulations for efficient prescreening of asphaltene inhibitors. In this study, MD is employed to screen six potential inhibitors, including cetyltrimethylammonium bromide (CTAB), octylphenol (OP), Triton X-100, 1-butyl-3-methylimidazolium bromide ([BMIM][Br]), 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]), and 1-octyl-3-methylimidazolium chloride ([OMIM][Cl]). The results conclude that CTAB has the highest inhibitory effect on asphaltene precipitation in n-heptane and heptol at both atmospheric and elevated thermodynamic conditions (pressure of 60 bar and temperature of 360 K). OP is selected as the second-ranked inhibitor in n-heptane, while Triton X-100 prevents asphaltene precipitation better than OP when heptol is the carrying fluid. Ionic liquids show weaker inhibitory effects compared to surfactants. Nevertheless, [OMIM][Cl] is selected as the best ionic liquid to prevent asphaltene precipitation in n-heptane at atmospheric conditions, while [BMIM][Cl] is selected as the best one in heptol. Hence, inhibitor screening tests for asphaltene precipitation consistently demonstrate CTAB as the most effective inhibitor. Subsequently, the CTAB performance is studied on the prevention of asphaltene deposition in a calcite pore. The results show that the presence of CTAB reduces the asphaltene deposition by about 30%. The lab scale cost ranking of inhibitors, from low to high, is as follows: Triton X-100, CTAB, [BMIM][Cl], [BMIM][Br], [OMIM][Cl], and OP. This shows CTAB has economic benefit over the others, while further field scale cost evaluation is needed before a final decision. This research introduces a cost-effective and efficient screening method for selecting chemical compounds based on molecular interactions. The introduced method for inhibitor screening is less expensive and faster than regular experimental approaches, while it provides proven accuracy compared with experimental techniques.