Cheremisin, Alexey N

Askarova A., Alekhina T., Zolfaghari S.M., Popov E., Afanasev P., Mukhametdinova A., Hosseinpour M., Soltani M., Cheremisin A., Mukhina E.

Alekhina T., Mukhametdinova A., Khayrullina A., Afanasev P., Askarova A., Popov E., Cheremisin A., Mukhina E.

Askarova A., Alekhina T., Fazlyeva R., Popov E., Mehta S.A., Moore R.G., Ursenbach M.G., Cheremisin A.

Pereponov D., Kazaku V., Scerbacova A., Avdonin A., Tarkhov M., Rykov A., Filippov I., Krutko V., Maksyutin A., Cheremisin A., Shilov E.

Mukhametdinova A., Karamov T., Markovic S., Morkovkin A., Burukhin A., Popov E., Sun Z., Zhao R., Cheremisin A.

Laboratory modeling of in-situ combustion is crucial for understanding the potential success of field trials in thermal enhanced oil recovery and is a vital precursor to scaling the technology for field applications. The high combustion temperatures, reaching up to 480°C, induce significant petrophysical alterations of the rock, an often overlooked aspect in thermal EOR projects. Quantifying these changes is essential for potentially repurposing thermally treated, depleted reservoirs for CO2 storage. In this study, we depart from conventional combustion experiments that use crushed core, opting instead to analyze the thermal effects on reservoir properties of carbonate rocks using consolidated samples. This technique maintains the intrinsic porosity and permeability, revealing combustion's impact on porosity and mineralogical alterations, with a comparative analysis of these properties pre- and post-combustion. We characterize porosity and pore geometry evolution using low-field nuclear magnetic resonance, X-ray micro-computed tomography, and low-temperature nitrogen adsorption. Mineral composition of the rock and grain-pore scale alterations are analyzed by scanning electron microscopy and X-ray diffraction. The analysis shows a significant increase in carbonate rocks' porosity, pore size and mineral alterations, and a transition from mixed-wet to a strongly water-wet state. Total porosity of rock samples increased in average for 15%–20%, and formation of new pores is registered at the scale of 1–30 μm size. High-temperature exposure results in the calcite and dolomite decomposition, calcite dissolution and formation of new minerals – anhydrite and fluorite. Increased microporosity and the shift to strongly water-wet rock state improve the prospects for capillary and residual CO2 trapping with greater capacity. Consequently, these findings highlight the importance of laboratory in-situ combustion modeling on consolidated rock over tests that use crushed core, and indicate that depleted combustion stimulated reservoirs may prove to be viable candidates for CO2 storage.

Bello A., Dorhjie D.B., Ivanova A., Cheremisin A.

Carbon Capture, Utilization, and Storage (CCUS) offers a viable solution to reduce the carbon footprint in the petroleum industry, and foam injection presents a promising method to achieve this while simultaneously increasing oil recovery. In this work, we studied the feasibility of CO2 foam for co-optimizing enhanced oil recovery and CO2 storage in a high-salinity carbonate formation. The simulated hydrodynamic model is a depleted formation containing 30% residual oil, with three mechanisms for CO2 storage: solubility, residual, and mineralization trapping mechanisms. The results showed that after 20 years, oil recovery during foam injection was 2.7 times higher than CO2 injection, and the CO2 stored during foam flooding was 38% higher than CO2 injection. Notably, foam injection also increased CO2 storage capacity by 2.6 times, indicating the potential to store around 2 gigatons of CO2 in the simulated model. This was attributed to the ability of foam to significantly reduce gas mobility and thus form isolated bubbles through its Jamin effect. Residual trapping was the dominant trapping mechanism, contributing to over 70% of the total CO2 trapped, attributed to the reduction in the dissolution of CO2 in brine due to the high salinity of the aqueous medium. CO2 mineralization was also studied, showing the least trapping efficiency and the dissolution trend of all the carbonate minerals. This study illustrates a novel CO2 utilization and storage technique in which CO2 is concurrently sequestered while enhancing oil recovery in a depleted oil reservoir by injecting CO2 as foam. The relevance of this study lies in its potential to provide a dual benefit of reducing greenhouse gas emissions and boosting oil production, offering a sustainable approach for the petroleum industry.

Afanasev P., Askarova A., Alekhina T., Popov E., Markovic S., Mukhametdinova A., Cheremisin A., Mukhina E.

Bello A., Ivanova A., Bakulin D., Yunusov T., Cheremisin A.

Surfactants are crucial in chemical enhanced oil recovery, but high adsorption onto rocks reduces their efficiency and economic viability. Sacrificial agents, such as alkalis, nanoparticles, and polymers have been investigated to mitigate this issue but they in turn present drawbacks such as poor oil interaction, compatibility issues, pore plugging, and increased costs. Binary surfactant systems, due to their favorable potential synergistic interactions, are proposed as solutions for reducing surfactant adsorption. Static adsorption experiments were conducted to assess the effect of the binary surfactants on adsorption efficiency, and the impact of salinity on the adsorption process equilibrium was also studied. Five core flooding experiments under reservoir temperature (41 ∘C), reservoir pressure (21 MPa), and high salinity (23.4 wt.%) were conducted to evaluate dynamic adsorption. The surfactant concentrations in supernatant and effluent, after the adsorption process were determined via interfacial tension tests using a spinning drop method. The results showed a significant reduction in surfactant adsorption on carbonate rocks, from 9.99 mg/g-rock to 0.68 mg/g-rock for anionic surfactants and from 5.38 mg/g-rock to 0.19 mg/g-rock for zwitterionic surfactants, with corresponding dynamic reductions of 61% and 89%. Our results were further evidenced by the little to no changes in the differential pH curves in the adsorption process of the binary surfactant systems. This study presents a cost-effective approach for significantly reducing surfactant adsorption on carbonate rocks and aids in designing surfactant formulations for adsorption reduction in high-temperature, high-salinity carbonate reservoirs.

Mukhina E., Afanasev P., Mukhametdinova A., Alekhina T., Askarova A., Popov E., Cheremisin A.

Hydrogen has been proven as a promising energy resource for a clean and sustainable future. However, the complete replacement of conventional hydrocarbon energy sources poses a challenge due to their widespread industrial utilization. Despite the gradual depletion of petroleum and natural gas reserves, they continued to serve as primary energy sources for many decades. But what if we could repurpose these hydrocarbons? Currently, fossil fuels that are both non-renewable and environmentally unfriendly are directly used for energy generation. Instead, we could convert hydrocarbons into a significantly cleaner alternative – hydrogen. This process implies in situ hydrogen generation even before hydrocarbons are recovered from a reservoir without releasing greenhouse gases into the atmosphere. In this context, we explore the conversion of methane into hydrogen in the gas reservoir with zero oil saturation via steam methane reforming initiated by in situ gas combustion. In the experimental model, different rock porous media were utilized and the process parameters such as temperature and the steam-to-methane ratio were varied. The outcome reveals a range of variations, each yielding different concentrations of hydrogen produced depending on these adjustable parameters. Our findings suggest the incredible potential for underground hydrogen generation in natural gas reservoirs. This approach holds great promise as a leading candidate for the foreseeable future, benefiting from the synergy of the fossil fuel industry and an innovative hydrogen production technology.

Zelentsov D.O., Petrova Y.Y., Egorova V.V., Povalyaev P.V., Frantsina E.V., Ivanova A.A., Cheremisin A.N., Sivkov A.A., Shanenkov I.I., Nassyrbayev A., Nikitin D.S.

Ti–O Magneli phases and carbon nanoparticles modified in sodium dodecyl sulfate solutions formed stable dispersions in water.

Uskova E.I., Burukhin A.A., Cheremisin A.N.

Dorhjie D.B., Pereponov D., Aminev T., Gimazov A., Khamidullin D., Kuporosov D., Tarkhov M., Rykov A., Filippov I., Mukhina E., Shilov E., Grishin P., Cheremisin A.

Bello A., Ivanova A., Bakulin D., Yunusov T., Rodionov A., Burukhin A., Cheremisin A.

AbstractA key factor affecting foam stability is the interaction of foam with oil in the reservoir. This work investigates how different types of oil influence the stability of foams generated with binary surfactant systems under a high salinity condition. Foam was generated with binary surfactant systems, one composed of a zwitterionic and a nonionic surfactant, and the other composed of an anionic and a nonionic surfactant. Our results showed that the binary surfactant foams investigated are more tolerant under high salinity conditions and in the presence of oil. This was visually observed in our microscopic analysis and was further attributed to an increase in apparent viscosity achieved with binary surfactant systems, compared to single surfactant foams. To understand the influence of oil on foam stability, we performed a mechanistic study to investigate how these oils interact with foams generated with binary surfactants, focusing on their applicability under high salinity conditions. The generation and stability of foam are linked to the ability of the surfactant system to solubilize oil molecules. Oil droplets that solubilize in the micelles appear to destabilize the foam. However, oils with higher molecular weights are too large to be solubilized in the micelles, hence the molecules will have less ability to be transported out of the foam, so oil seems to stabilize the foam. Finally, we conducted a multivariate analysis to identify the parameters that influenced foam stability in different oil types, using the experimental data from our work. The results showed that the oil molecular weight, interfacial tension between the foaming liquid and the oil, and the spreading coefficient are the most important variables for explaining the variation in the data. By performing a partial least square regression, a linear model was developed based on these most important variables, which can be used to predict foam stability for subsequent experiments under the same conditions as our work.

Dorhjie D.B., Cheremisin A.

Abstract Hydrogen is poised to become one of the most promising alternative clean sources of energy for climate change mitigation. The development of a sustainable hydrogen economy depends on the global implementation of safe and economically feasible intersessional hydrogen storage and recovery. However, the current body of literature lacks comprehensive numerical characterization of the multiphase flow of hydrogen-brine and how geological parameters at the pore scale influence the multiphase flow. This study presents a pore network simulation of hydrogen-brine and cushion gas-brine relative permeabilities. Initially, the generated pore network model was validated against the characteristics of the core sample, such as porosity, permeability, and pore size distribution. In addition, the model was adapted to replicate the results of the drainage capillary pressure curves and relative permeability curves observed in the laboratory experiment. Furthermore, a sensitivity analysis was conducted to quantify the effects of fluid and rock properties on the relative permeabilities of the fluids. The results indicate that the capillary pressure and the relative permeability of the hydrogen and brine are sensitive to the distribution of the surface contact angle. The relative permeability of hydrogen phase decreases as the frequency of pores with stronger water-wet contact angle values increases. The relative permeability endpoint (residual saturation) was also significantly influenced by pore and throat shape, pore and throat size distribution, and pore connectivity. Simulations of different cushion gases revealed that the relative permeabilities of CH4 and N2 are similar to hydrogen. This research offers a comprehensive pore-scale prediction of the relative permeability of hydrogen and brine systems and presents the parameters and cushion gases to consider in the selection of geological storage sites for hydrogen storage.

Askarova A.G., Afanasev P.A., Popov E.Y., Cheremisin A.N., Malaniy S.E., Volkov D.A., Cheremisin A.N.

Abstract There has been a growing trend in the energy sector toward hydrogen generation due to the market’s rising need for hydrogen. This change has led to a larger emphasis on creating methods and tools for subsurface hydrogen production from hydrocarbons. This research determines the features of the process of In-situ Hydrogen Generation (ISHG) and interprets the results of laboratory tests to build a scheme of kinetic reactions. A combustion tube experiment of methane combustion in porous media was conducted to reproduce the process of hydrogen synthesis from methane under reservoir conditions (high pressure and temperatures) created by the In-situ Combustion (ISC) technology. Further numerical modelling allows validating the kinetic model typical for methane combustion in a pores medium, removing uncertainties and determining the favorable conditions for hydrogen generation (temperature, steam-methane ratio, injection rate). During numerical simulation, good convergence of numerical simulation results with experimental data was obtained, namely the temperature profile, cumulative gas production, and molar concentrations of gas components such as H2, CH4, CO and CO2, as the main indicators of the kinetic model adaptation quality. The methane steam reforming and methane cracking reactions demonstrated the highest contribution to producing gases. The constructed kinetic model was history-matched to the experiment of the combustion tube to assess the advancement of the high-temperature front, the transformations occurring in a given zone of elevated temperatures and the adaptation of the curves of relative-phase characteristics for the subsequent assessment of the method’s effectiveness. The obtained kinetic model and relative permeability curves were used in field-scale modelling. The up-scaled field model considered a few development strategies using existing infrastructure to optimize the hydrogen generation yield. This paper determines the features of the process of ISHG and interprets the laboratory test results to build a scheme of kinetic reactions. The obtained kinetic model was used further in a field-scale model to assess the feasibility of hydrogen generation using existing infrastructure.

Fu C., Huang K., Chen H., Huang B., Zhang W.

Wu H., Yao Y., Duan J., Niu M., Chen D., Zi M.

Askarova A., Alekhina T., Zolfaghari S.M., Popov E., Afanasev P., Mukhametdinova A., Hosseinpour M., Soltani M., Cheremisin A., Mukhina E.

Zhang Y., Li R., Guo Q., Song F., Kai K., Chen Q.

Li K., Yin Z., Yang Z., Liu Y.

Zhang S., Ma Y., Huang Y., Xu Z., Liu X., Jiang S., You X., Wang Y., Zhong X., Chen C.

Ren J., Xiao W., Cheng Q., Song P., Bai X., Xie Q., Pu W., Zheng L.

Wang J., Liu Y., Zhang B., Zhang B., He Y., Chai R.

Izadpanahi A., Ranazzi P., Abraham-A R.M., Gaeta Tassinari C.C., Sampaio M.A.

Sun H., Wang S., Wang S., Song Y., Ling Z., Zhang L.

Shu Y., Liu B., Zhang H., Zhou A., Zhang S., Shi Z., Hu Z., Wang X.

Kan J., Yang J., Li Z., Xu Z., Li N., Chen G.

Gao Q., Jiang X., Wang Z., Yang Z., Trivedi J., Xu X., Mmbuji A.O., Patel V.

Quintella C.M., Rodrigues P.D., Ramos-de-Souza E., Carvalho E.B., Nicoleti J.L., Hanna S.A.

Hanxuan S., Jixiang G., Kiyingi W., Xiwen W., Aiguo H., Jiao L., Li W., Xiangwei C.

Yuan C., Afanasev P., Askarova A., Popov E., Cheremisin A.

Askarova A., Alekhina T., Popov E., Afanasev P., Mukhametdinova A., Smirnov A., Cheremisin A., Mukhina E.

Alekhina T., Mukhametdinova A., Khayrullina A., Afanasev P., Askarova A., Popov E., Cheremisin A., Mukhina E.

Mukhametdinova A., Karamov T., Markovic S., Morkovkin A., Burukhin A., Popov E., Sun Z., Zhao R., Cheremisin A.

Laboratory modeling of in-situ combustion is crucial for understanding the potential success of field trials in thermal enhanced oil recovery and is a vital precursor to scaling the technology for field applications. The high combustion temperatures, reaching up to 480°C, induce significant petrophysical alterations of the rock, an often overlooked aspect in thermal EOR projects. Quantifying these changes is essential for potentially repurposing thermally treated, depleted reservoirs for CO2 storage. In this study, we depart from conventional combustion experiments that use crushed core, opting instead to analyze the thermal effects on reservoir properties of carbonate rocks using consolidated samples. This technique maintains the intrinsic porosity and permeability, revealing combustion's impact on porosity and mineralogical alterations, with a comparative analysis of these properties pre- and post-combustion. We characterize porosity and pore geometry evolution using low-field nuclear magnetic resonance, X-ray micro-computed tomography, and low-temperature nitrogen adsorption. Mineral composition of the rock and grain-pore scale alterations are analyzed by scanning electron microscopy and X-ray diffraction. The analysis shows a significant increase in carbonate rocks' porosity, pore size and mineral alterations, and a transition from mixed-wet to a strongly water-wet state. Total porosity of rock samples increased in average for 15%–20%, and formation of new pores is registered at the scale of 1–30 μm size. High-temperature exposure results in the calcite and dolomite decomposition, calcite dissolution and formation of new minerals – anhydrite and fluorite. Increased microporosity and the shift to strongly water-wet rock state improve the prospects for capillary and residual CO2 trapping with greater capacity. Consequently, these findings highlight the importance of laboratory in-situ combustion modeling on consolidated rock over tests that use crushed core, and indicate that depleted combustion stimulated reservoirs may prove to be viable candidates for CO2 storage.

Okere C.J., Sheng J.J.

The increasing demand for eco-friendly and renewable energy has positioned hydrogen as a viable solution for global energy and environmental challenges. In-situ combustion gasification of heavy oil reservoirs offers potential for large-scale hydrogen production, injecting steam and air (or alternative gases) to trigger complex chemical reactions leading to hydrogen and syngas generation. However, a research gap exists due to the lack of a comprehensive numerical model for accurately simulating hydrogen production under SARA-based (saturate, aromatic, resin, asphaltene) hydrocarbon characterization in experiments and field study. This study addresses the gap by investigating in-situ combustion gasification for hydrogen generation in heavy oil reservoirs. A novel model based on SARA characterization is proposed, showing fidelity with experimental and numerical results. Different injection strategies, like pure oxygen and CO2, impact hydrogen production. Oxygen injection yields less hydrogen than air injection, highlighting the importance of oxygen control. CO2 injection reduces hydrogen but aids carbon management. The oxygen to nitrogen ratio (61/39) demonstrates the highest hydrogen-to-syngas ratio. Practical implementation requires economic feasibility, operational practicality, safety, and environmental considerations. This study advances in-situ combustion gasification technology, facilitating efficient and sustainable hydrogen generation from heavy oil reservoirs.

Saadat Z., Farazmand M., Sameti M.

One of the major challenges in harnessing energy from renewable sources like wind and solar is their intermittent nature. Energy production from these sources can vary based on weather conditions and time of day, making it essential to store surplus energy for later use when there is a shortfall. Energy storage systems play a crucial role in addressing this intermittency issue and ensuring a stable and reliable energy supply. Green hydrogen, sourced from renewables, emerges as a promising solution to meet the rising demand for sustainable energy, addressing the depletion of fossil fuels and environmental crises. In the present study, underground hydrogen storage in various geological formations (aquifers, depleted hydrocarbon reservoirs, salt caverns) is examined, emphasizing the need for a detailed geological analysis and addressing potential hazards. The paper discusses challenges associated with underground hydrogen storage, including the requirement for extensive studies to understand hydrogen interactions with microorganisms. It underscores the importance of the issue, with a focus on reviewing the the various past and present hydrogen storage projects and sites, as well as reviewing the modeling studies in this field. The paper also emphasizes the importance of incorporating hybrid energy systems into hydrogen storage to overcome limitations associated with standalone hydrogen storage systems. It further explores the past and future integrations of underground storage of green hydrogen within this dynamic energy landscape.

Ikpeka P., Alozieuwa E., Duru U.I., Ugwu J.

Energy transition is a key driver to combat climate change and achieve zero carbon future. Sustainable and cost-effective hydrogen production will provide valuable addition to the renewable energy mix and help minimize greenhouse gas emissions. This study investigates the performance of in-situ hydrogen production (IHP) process, using a full-field compositional model as a precursor to experimental validation The reservoir model was simulated as one geological unit with a single point uniform porosity value of 0.13 and a five-point connection type between cell to minimize computational cost. Twenty-one hydrogen forming reactions were modelled based on the reservoir fluid composition selected for this study. The thermodynamic and kinetic parameters for the reactions were obtained from published experiments due to the absence of experimental data specific to the reservoir. A total of fifty-four simulation runs were conducted using CMG STARS software for 5478 days and cumulative hydrogen produced for each run was recorded. Results generated were then used to build a proxy model using Box-Behnken design of experiment method and Support Vector Machine with RBF kernel. To ascertain accuracy of the proxy models, analysis of variance (ANOVA) was conducted on the variables. The average absolute percentage error between the proxy model and numerical simulation was calculated to be 10.82%. Optimization of the proxy model was performed using genetic algorithm to maximize cumulative hydrogen produced. Based on this optimized model, the influence of porosity, permeability, well location, injection rate, and injection pressure were studied. Key results from this study reveals that lower permeability and porosity reservoirs supports more hydrogen yield, injection pressure had a negligible effect on hydrogen yield, and increase in oxygen injection rate corelated strongly with hydrogen production until a threshold value beyond which hydrogen yield decreased. The framework developed in the study could be used as tool to assess candidate reservoirs for in-situ hydrogen production.

Afanasev P., Askarova A., Alekhina T., Popov E., Markovic S., Mukhametdinova A., Cheremisin A., Mukhina E.

Mukhina E., Afanasev P., Mukhametdinova A., Alekhina T., Askarova A., Popov E., Cheremisin A.

Hydrogen has been proven as a promising energy resource for a clean and sustainable future. However, the complete replacement of conventional hydrocarbon energy sources poses a challenge due to their widespread industrial utilization. Despite the gradual depletion of petroleum and natural gas reserves, they continued to serve as primary energy sources for many decades. But what if we could repurpose these hydrocarbons? Currently, fossil fuels that are both non-renewable and environmentally unfriendly are directly used for energy generation. Instead, we could convert hydrocarbons into a significantly cleaner alternative – hydrogen. This process implies in situ hydrogen generation even before hydrocarbons are recovered from a reservoir without releasing greenhouse gases into the atmosphere. In this context, we explore the conversion of methane into hydrogen in the gas reservoir with zero oil saturation via steam methane reforming initiated by in situ gas combustion. In the experimental model, different rock porous media were utilized and the process parameters such as temperature and the steam-to-methane ratio were varied. The outcome reveals a range of variations, each yielding different concentrations of hydrogen produced depending on these adjustable parameters. Our findings suggest the incredible potential for underground hydrogen generation in natural gas reservoirs. This approach holds great promise as a leading candidate for the foreseeable future, benefiting from the synergy of the fossil fuel industry and an innovative hydrogen production technology.

Hosseinpour M., Fakhroleslam M., Djimasbe R., Al-Muntaser A.A., Suwaid M.A., Khelil I., Varfolomeev M.A., Nurgaliev D.K.

Kovalskii A.M., Manakhov A.M., Afanasev P.A., Popov Z.I., Matveev A.T., Al-Qasim A.S.

The development of hydrogen energy is capable of solving a number of important issues that modern society is facing, including global warming and various environmental impacts. Currently, there is an intensive search for natural sources of hydrogen as well as low-carbon techniques for mass production of hydrogen from natural gas, associated petroleum gas, and water. In parallel, efforts to develop technologies for the subsequent management of hydrogen are underway, and the creation of its safe and efficient storage is one of the highest priority goals. For the transportation and storage of hydrogen today, a number of solutions are offered, each of which has both positive and negative aspects. The boron nitride family of materials with high thermal and chemical stability, variability of morphologies, and flexibility of structure has been considered as a candidate for efficient hydrogen storage. This review offers to familiarize readers with the progress in the research and application of hexagonal boron nitride (h-BN), as well as BN-based materials in comparison with other materials, as promising hydrogen storage. Experimental and theoretical data obtained for different morphologies and internal structures were reviewed in relevance to the material`s sorption capacity with respect to hydrogen. Various approaches to improve the efficiency of hydrogen storage were analyzed, and the highest storage capabilities published were mentioned. Thus, BN-based materials are very promising as hydrogen storage, even for an automotive application, but the development of new mass production technologies should be carried out.

Manafzadeh P., Habibiyan H., Hosseinpour M., Talebi S.

The first part of the current study highlights the importance of developing a clean hydrogen supply chain (CHSC) in Iran to enhance energy security and contribute to global efforts towards sustainable energy transition. Depending on whether the focus is on domestic consumption or export of hydrogen, the study provides valuable insights into the prioritization of CHSC development pathways via multi-criteria decision-making tools (AHP, AHOP-TOPSIS, and AHP-VIKOR). The results show that for domestic hydrogen consumption (internal scenario), the best path of the supply chain includes blue hydrogen from steam methane reforming coupled with carbon capture and storage, H2-carriers (ammonia and methanol), natural gas grid for transportation and distribution, and industry sector as the end user. In the external scenario, however, the best path of the CHSC consists of green hydrogen production based on solar energy, and the other parts of the path include liquid hydrogen as the storage method, ship as the distribution and transportation, and industrial sector as the end user. By identifying the most suitable methods and technologies for each stage of the supply chain, this paper offers a comprehensive analysis that can guide decision-making in CHSC development.

Sarkar M., Bhattacharya P., Chatterjee H., Sarkar S., Mandal B., Biswas S., Ghosh S.K., De S.

Substoichiometric titanium oxides i.e. Magneli phase (MP) TiOx are attractive due to their conductive nature. However, their synthesis is challenging. In this work, Anisotropic MP- Ti4O7 nanoparticles and Au doped nanocomposites were synthesized using β- cyclodextrin as template. The MP nanomaterials were 20-30 nm in size. The synthesis conditions were mild. These MP- TiOx nanomaterials show efficient charge separation upon light excitation i.e. they (i) act as efficient photocatalysts; (ii) they can be sensitized by a fluorescent dye; (iii) finite element method (FEM) simulations indicate substantial interfacial plasmonic charge generation at the metal-semiconductor interface in the doped nanocomposites.

Bello A., Ivanova A., Bakulin D., Yunusov T., Rodionov A., Burukhin A., Cheremisin A.

AbstractA key factor affecting foam stability is the interaction of foam with oil in the reservoir. This work investigates how different types of oil influence the stability of foams generated with binary surfactant systems under a high salinity condition. Foam was generated with binary surfactant systems, one composed of a zwitterionic and a nonionic surfactant, and the other composed of an anionic and a nonionic surfactant. Our results showed that the binary surfactant foams investigated are more tolerant under high salinity conditions and in the presence of oil. This was visually observed in our microscopic analysis and was further attributed to an increase in apparent viscosity achieved with binary surfactant systems, compared to single surfactant foams. To understand the influence of oil on foam stability, we performed a mechanistic study to investigate how these oils interact with foams generated with binary surfactants, focusing on their applicability under high salinity conditions. The generation and stability of foam are linked to the ability of the surfactant system to solubilize oil molecules. Oil droplets that solubilize in the micelles appear to destabilize the foam. However, oils with higher molecular weights are too large to be solubilized in the micelles, hence the molecules will have less ability to be transported out of the foam, so oil seems to stabilize the foam. Finally, we conducted a multivariate analysis to identify the parameters that influenced foam stability in different oil types, using the experimental data from our work. The results showed that the oil molecular weight, interfacial tension between the foaming liquid and the oil, and the spreading coefficient are the most important variables for explaining the variation in the data. By performing a partial least square regression, a linear model was developed based on these most important variables, which can be used to predict foam stability for subsequent experiments under the same conditions as our work.

Dorhjie D.B., Cheremisin A.

Abstract Hydrogen is poised to become one of the most promising alternative clean sources of energy for climate change mitigation. The development of a sustainable hydrogen economy depends on the global implementation of safe and economically feasible intersessional hydrogen storage and recovery. However, the current body of literature lacks comprehensive numerical characterization of the multiphase flow of hydrogen-brine and how geological parameters at the pore scale influence the multiphase flow. This study presents a pore network simulation of hydrogen-brine and cushion gas-brine relative permeabilities. Initially, the generated pore network model was validated against the characteristics of the core sample, such as porosity, permeability, and pore size distribution. In addition, the model was adapted to replicate the results of the drainage capillary pressure curves and relative permeability curves observed in the laboratory experiment. Furthermore, a sensitivity analysis was conducted to quantify the effects of fluid and rock properties on the relative permeabilities of the fluids. The results indicate that the capillary pressure and the relative permeability of the hydrogen and brine are sensitive to the distribution of the surface contact angle. The relative permeability of hydrogen phase decreases as the frequency of pores with stronger water-wet contact angle values increases. The relative permeability endpoint (residual saturation) was also significantly influenced by pore and throat shape, pore and throat size distribution, and pore connectivity. Simulations of different cushion gases revealed that the relative permeabilities of CH4 and N2 are similar to hydrogen. This research offers a comprehensive pore-scale prediction of the relative permeability of hydrogen and brine systems and presents the parameters and cushion gases to consider in the selection of geological storage sites for hydrogen storage.