Search Results (1,790)

Steam-assisted gravity drainage (SAGD) makes a significant contribution to Canada’s heavy oil production. Yet, it faces notable efficiency challenges during late-life stages, characterized by increased Steam–Oil Ratios and environmental concerns. Non-condensable gas (NCG) injection has emerged as a promising strategy to address these issues, particularly in late-life and post-steam SAGD phases. This review systematically examines the mechanisms, phase behavior, thermochemical interactions, field applications, and operational impacts of injecting NCGs such as methane, nitrogen, and carbon dioxide. This work exclusively synthesizes the application of NCG injections in mature SAGD reservoirs while outlining existing challenges. It delivers a unified perspective on this domain, introducing practical insights to improve NCG injection efficiency. Critical analysis of the existing literature reveals key benefits, including reservoir pressure maintenance, steam chamber stabilization, and viscosity reduction. However, literature gaps persist regarding long-term field-scale validation, complex drive mechanisms at the steam chamber flanks, thermochemical reactions, interactions with geological heterogeneity, and detailed thermodynamic modeling under non-equilibrium conditions. Emphasizing these gaps underscores the importance of further research and integrated modeling to optimize NCG utilization, thus enhancing recovery efficiency, reducing environmental footprints, and extending reservoir life. Full article

The Cretaceous shallow oil sands in the Dagang area, located on the western slope of the Songliao Basin, are characterized by a burial depth of ≤182 m, an average reservoir temperature of 11.8 °C, an extremely high crude oil viscosity of 1,750,000 mPa·s at 15 °C, and water-bearing layers in both the roof and floor. Conventional thermal recovery methods such as SAGD and CSS are geologically unsuitable for this deposit and suffer from high energy consumption and carbon emissions. As microbial oil recovery is a technically advanced enhanced oil recovery technology that leverages microbial growth, reproduction and metabolism in the reservoir to alter the properties of oil, rock, gas and water through interaction with these components, and petroleum biotechnology research confirms that microorganisms can degrade high-molecular-weight petroleum hydrocarbons to reduce crude oil viscosity and improve its fluidity, this study explores the technical feasibility of microbial cold recovery for in situ extraction of such low-temperature, high-viscosity oil sands. The study adopts a five-well pilot pattern (one injector and four producers) with an integrated approach combining reservoir unblocking, microbial viscosity reduction, and vibration-assisted production. Systematic screening identified Pseudomonas, Chryseobacterium, and Citrobacter as the most efficient indigenous microbial strains. Pseudomonas exhibited a crude oil degradation rate of 32.17%, reducing asphaltene content from 7.47% to 3.56%, and achieved large-scale proliferation (2.5 × 10⁸ cfu/mL) at 15 °C. It also achieved a 40.8% reduction in crude oil viscosity and a desulfurization rate, alongside 56.6% denitrification. With the optimal activator No. 3, the viscosity reduction rate reached 45.18%, and the viable cell count exceeded 9.45 × 10⁸ cfu/mL. The synergistic action of Pseudomonas and an A-type nano-microemulsion surfactant reduced the oil–water interfacial tension from 49.56 to 1.25 mN/m (a 97.48% reduction) and lowered the crude oil viscosity at 25 °C from 302,000 to 11,023 mPa·s (a 96.35% reduction). Core flooding tests demonstrated an incremental oil recovery of 7.38% compared with the water-flooded control, with interfacial tension dropping from 48.21 to 1.18 mN/m. In the field trial, composite perforation (32 shots/m, 1610 mm penetration) and two cycles of oil-based fermentation fluid huff-n-puff reduced injection pressure from 2.0 to 2.5 MPa to 1.0–1.8 MPa. A total of 1489 m³ of microbial agent was injected into five wells, followed by a 125-day shut-in period. Nano-microemulsion single-well huff-n-puff (579 m³ over 87 days) further decreased injection pressure to 0 MPa. A downhole harmonic vibration source (≤20 Hz) was also applied during the trial. During the production phase, Pseudomonas was found to dominate the produced fluid, with its peak relative abundance exceeding 70%. Cumulative fluid production reached 4114 m³, yielding 21 m³ of oil sand oil. Wells with vibration assistance showed significantly higher oil content and better emulsification performance than wells without vibration assistance. Full article

Understanding pore-scale interactions among CO₂, the aqueous phase, and heavy oil is crucial for optimizing surfactant-assisted CO₂-enhanced oil recovery. In this study, a three-phase volume-of-fluid (VOF) framework is established in OpenFOAM to simulate immiscible displacement in two-dimensional porous media composed of circular solid grains. Two pore geometries are considered: a relatively uniform geometry and a preferential-channel geometry designed to promote early breakthrough. Sixteen injection schemes are compared, including pure CO₂ flooding, ordinary-water flooding, surfactant–water flooding, aqueous-phase preflush followed by CO₂ injection, and cyclic aqueous-phase/CO₂ injection with different aqueous-slug durations and switching frequencies. The effects of pore geometry, injection strategy, capillary number, viscosity ratio, interfacial tension, and wettability are evaluated using pore-volume-normalized oil recovery, breakthrough PV (the ratio of injected volume to pore volume), cumulative injected CO₂ PV at breakthrough, and phase-distribution indicators. The results show that pore geometry strongly affects macroscopic sweep and breakthrough behavior. In the preferential-channel geometry, pure CO₂ flooding and continuous ordinary-water flooding suffer from early breakthrough and poor sweep, whereas continuous surfactant–water flooding maintains high recovery because reduced oil–water interfacial tension and a more water-wet wall condition promote oil-film detachment and residual-oil mobilization. At 2.5 injected PV, the high-frequency short-slug and 1 s surfactant–water cyclic schemes give the highest or near-highest recovery in the relatively uniform geometry, while continuous surfactant–water flooding remains the highest-recovery scheme in the preferential-channel geometry. Considering the higher chemical demand of continuous surfactant injection and the carbon-utilization objective of CO₂-EOR, the combined surfactant–water/CO₂ schemes are evaluated to clarify the coupling between surfactant-induced oil mobilization and CO₂ displacement. Surfactant–water preflush followed by CO₂ injection becomes more effective as the preflush duration increases, and its recovery advantage over ordinary-water preflush is especially large in the preferential-channel geometry. However, the increase in CO₂ breakthrough PV in this geometry is limited compared with the recovery increment, indicating that the main benefit of surfactant–water is not only delayed gas breakthrough but also enhanced microscopic oil mobilization in poorly swept regions. Increasing the switching frequency slightly improves the cyclic response in the relatively uniform geometry under the tested schedules, whereas all cyclic schemes remain strongly constrained by reconnection with the dominant gas pathway in the preferential-channel geometry. Within the present idealized immiscible VOF model, these comparisons provide a controlled pore-scale comparison for distinguishing surfactant-induced residual-oil mobilization from CO₂ gas-channeling effects in heavy-oil porous media. Full article

The global wine industry generates substantial volumes of by-products, leading to significant environmental and economic challenges. This study explores the sustainable valorization of two key by-products from Moldovan red wine production—yeast lees and grape skin powder derived from autochthonous grape varieties Rară Neagră (RN) and Fetească Neagră (FN)—within the circular economy paradigm. Comprehensive physicochemical analyses demonstrated that yeast lees are a rich source of bioactive β-glucans (20.17–21.91%, w/w wet lees), proteins, and triglycerides; β-glucans of this type are reported in the literature to confer immunomodulatory and antioxidant properties, although these bioactivities were not directly evaluated in the present study. Grape skin powders exhibited high dietary fibre content and polyphenolic compounds, with FN showing superior total polyphenol content and antioxidant activity compared to RN. Advanced extraction techniques using green solvents such as glycerol, propylene glycol, and ethanol, including ultrasound-assisted methods, optimized polyphenol recovery while maintaining extract stability. Incorporation of these extracts into innovative oil-in-water cosmetic emulsions revealed notable physicochemical characteristics, with the RN extracts enhancing emulsion firmness via polyphenol–xanthan gum interactions, and the FN extracts providing high antioxidant potential without compromising texture. A preliminary single-subject biophysical assessment suggested good short-term skin compatibility, with hydration improvement and reduced transepidermal water loss in several formulations and no visible pigmentation; these observations require confirmation in a larger volunteer panel with dedicated safety testing. This work provides laboratory-scale evidence of the dual environmental and functional potential of recovering and applying Moldovan winery by-products, supporting their further development—pending pilot-scale and economic validation—as bio-ingredients for the food, cosmetic, and pharmaceutical sectors within a circular bioeconomy framework. Full article

Lipases are important enzymes in the esterase family that hydrolyze ester bonds in triglycerides, producing simpler molecules. This property makes them valuable in biotechnology and environmental cleanup. In this study, lipase-producing bacteria were isolated and characterized from petroleum-contaminated soil to establish a cost-effective platform for enzyme production and bioremediation. Among the recovered isolates, Serratia liquefaciens AB1 exhibited the highest lipolytic activity and was therefore selected for further investigation. The influence of various inducer oils and agro-industrial residues on enzyme production was systematically assessed. In addition, fermentation parameters were optimized through the evaluation of different carbon and nitrogen sources to enhance lipase yield. Waste frying oil was identified as the most effective inducer, while glucose and yeast extract supported optimal enzyme production. The enzyme lipase AB1 was fully purified using CM-Sephadex C-50 chromatography, Sephadex G-100 and further characterized by SDS-PAGE, kinetic studies, and stability assays. Purification of the enzyme resulted in a specific activity of 610.92 U/mg, corresponding to a 9.42-fold increase in purity with an overall recovery of 76%. The enzyme exhibited an apparent molecular mass of approximately 64 kDa. It demonstrated optimal catalytic activity at 60 °C and pH 8 and retained substantial stability at this temperature for up to 120 min. Kinetic analysis revealed a low Km value of 30 µM, indicating strong substrate affinity, along with a Vmax of 23.89 U/mL, reflecting a high catalytic efficiency under the tested conditions. Enzyme activity was enhanced by Ca²⁺, Na⁺, and Ba²⁺, but inhibited by Mn²⁺ and Hg²⁺. These findings demonstrate the favorable biochemical properties of the purified lipase and provide a basis for future investigations into its potential application as a biocatalyst for bioremediation. Full article

Heavy oil reservoirs typically suffer from low recovery efficiency and high development costs during thermal production. This study investigates the A66 heavy oil reservoir and proposes an integrated hot-water flooding and hot-to-cold injection strategy. Laboratory experiments, numerical simulations, and techno-economic analysis are combined to optimize injection temperature, conversion timing, and injection parameters. Results show that injection temperature strongly affects oil recovery. Increasing temperature from 40 °C to 60 °C significantly improves recovery by reducing oil viscosity and enhancing mobility. However, further increases to 80 °C and 100 °C provide only marginal additional improvement, indicating a clear diminishing return effect. Considering both recovery performance and energy consumption, 60 °C is identified as the optimal injection temperature. Simulation results indicate that the timing of hot-to-cold conversion has a limited impact on final recovery, while significantly affecting development cost. A conversion window at a water cut of 10–20% achieves a balanced performance between displacement efficiency and thermal cost reduction. In addition, unstable injection improves sweep efficiency by dynamically adjusting flow paths and enhancing both areal and vertical displacement. A coupled hot-to-cold injection strategy is therefore proposed. It integrates temperature optimization, injection mode design, and conversion timing to improve both recovery and economic performance. Compared with conventional constant-temperature flooding, the proposed strategy better accounts for the time-dependent evolution of reservoir thermal conditions and fluid properties. Techno-economic evaluation confirms that the optimized scheme achieves higher economic efficiency while maintaining stable recovery improvement, demonstrating strong potential for field application in similar heavy oil reservoirs. Full article

Thermal variability associated with climate change is an increasing constraint for finfish aquaculture because water temperature directly affects feed intake, nutrient utilization, endocrine stress responses, oxidative balance, immunity, intestinal integrity and survival. The literature search was conducted without a lower publication-year restriction through 5 July 2026. Database and citation-linked searches identified 386 candidate records, of which 274 remained after duplicate removal; 71 full-text articles were assessed; and 28 peer-reviewed primary feeding studies with publicly available final versions of record were retained for qualitative evidence mapping. The eligible studies were published between 2012 and 2026, with 2012 representing the earliest eligible publication rather than a prespecified starting year. Functional aquafeeds have therefore emerged as promising nutritional tools for supporting physiological resilience under heat, cold and sub-optimal temperature conditions. This review developed a PRISMA-guided systematic evidence map of dietary functional-aquafeed strategies evaluated for thermal-stress tolerance, immune regulation, antioxidant defense and metabolic homeostasis in cultured finfish. The main synthesis emphasizes studies with direct dietary thermal-stress interventions and extractable mechanistic outcomes, including sodium butyrate, organic selenium, selenium nanoparticles with riboflavin, astaxanthin, Bacillus spp., propolis, bay laurel essential oil, Spirulina-based strategies and essential oils. Overall, the available evidence suggests that selected functional aquafeeds may support thermal-stress resilience through coordinated improvements in antioxidant capacity, reduced oxidative damage, modulation of cortisol/glucose and heat-shock responses, enhancement of innate and mucosal immunity, improved intestinal or tissue condition and stabilization of metabolic indicators. The most biologically coherent translational patterns were observed when dietary interventions improved multiple response domains simultaneously rather than a single biomarker. However, such cross-domain improvement was interpreted as mechanistic and translational support rather than as an independent indicator of evidence confidence, which depended primarily on independent replication, consistency of response direction and methodological quality. Nevertheless, the current evidence remains uneven across species, stress models, life stages and outcome domains, with limited data for marine carnivores, repeated temperature fluctuation, post-stress recovery, disease challenge and multiomics integration. Therefore, the findings should be interpreted as a structured evidence map rather than universal formulation guidance. Future studies should use standardized thermal-challenge protocols, dose–response designs, clear tank-level experimental-unit reporting and integrated biomarker panels to support practical development of climate-resilient functional aquafeeds. Full article

Excessive exercise without adequate recovery can induce prolonged fatigue, accompanied by skeletal muscle inflammation, oxidative stress, and impaired repair. Bergamot essential oil (BEO), a citrus-derived volatile essential oil, has been reported to have anti-inflammatory and antioxidant activities, but its effects on exercise-induced prolonged fatigue remain unclear. This study investigated the fatigue-relieving effects of long-term inhalation of BEO and its major constituents in a rat model of prolonged exercise-induced fatigue, with emphasis on skeletal muscle regulation. Rats were subjected to progressive exercise loading and exposed daily to BEO or its main components, followed by behavioral, biochemical, histological, transcriptional, and protein analyses. BEO inhalation significantly improved swimming endurance and alleviated fatigue-related physiological disturbances. In skeletal muscle, BEO reduced IL-1β and IL-6 levels, attenuated transcriptional changes in NF-κB/NLRP3-related inflammatory markers, decreased MDA accumulation, and enhanced GSH-Px activity. BEO also modulated muscle repair-related markers by reversing the abnormal elevation of Myod1 and restoring Myog mRNA expression. These effects were accompanied by increased Igf1 expression, restored PI3K protein expression, enhanced PI3K phosphorylation, and increased inhibitory phosphorylation of GSK3β. Overall, BEO alleviated prolonged exercise-induced fatigue by attenuating skeletal muscle inflammation, oxidative stress, and repair-related dysregulation, supporting its potential as a non-oral aromatic intervention for fatigue recovery. Full article

Chili products are vulnerable to the addition of unauthorized substances, including Sudan dyes, Rhodamine B, Basic Orange 2, poppy-derived materials and improperly used processing chemicals. Their analysis is complicated by the high contents of lipids, carotenoids, capsaicinoids and other co-extracted matrix components in chili powder, chili oil, chili sauce and composite seasonings. This review critically evaluates conventional and emerging sample-preparation strategies, including solid-phase extraction; the quick, easy, cheap, effective, rugged and safe (QuEChERS) procedure; deep eutectic solvent (DES)-assisted extraction; enhanced matrix removal for lipids (EMR-Lipid); and molecularly imprinted sorbents. Laboratory methods based on high-performance liquid chromatography (HPLC), liquid chromatography–tandem mass spectrometry (LC–MS/MS) and gas chromatography–mass spectrometry (GC–MS) are compared with enzyme-linked immunosorbent assay (ELISA), surface-enhanced Raman spectroscopy (SERS), electrochemical sensors, miniature mass spectrometry and artificial intelligence-assisted hyperspectral imaging (AI–HSI). The comparison considers representative limits of detection and quantification, recovery, precision, sample-preparation burden, cost, portability, validation status and regulatory role. LC–MS/MS remains the preferred confirmatory platform for targeted multi-residue analysis, whereas rapid and portable methods are more appropriate for screening and sample triage. A three-tier workflow linking rapid screening, laboratory confirmation, and emerging-risk identification and traceability is proposed. Future priorities include standardized chili reference materials, open AI training and validation datasets, greener DES-based extraction and interlaboratory validation of field-deployable methods. Full article

High-angle fractures are widely developed in ultra-low permeability reservoirs in the Ordos Basin, and their propagation has a significant influence on waterflooding performance. However, few studies have focused on the identification of high-angle fractures, let alone the impact of their propagation on waterflooding performance. Therefore, a waterflooding model considering dynamic fracture propagation was developed to evaluate the impact of fracture propagation on waterflooding performance in this study. Firstly, based on the logging response characteristics of high-angle fracture intervals, the high-angle fracture identification model was established by the fuzzy comprehensive evaluation method, and a comprehensive index was proposed to identify high-angle fracture intervals. A threshold of approximately 70 effectively distinguishes high-angle fracture intervals from non-high-angle fracture intervals. After that, the waterflooding model considering dynamic fracture propagation was established to investigate the effect of its parameters on waterflooding performance. A smaller initial leak-off coefficient and a faster decline rate reduce fluid loss, promote fracture propagation, and ultimately improve oil recovery. Higher injection rates promote dynamic fracture propagation, accelerate water cut rise, mitigate production decline, and enhance cumulative oil production, while improving the waterflooding response of wells along the fracture direction. Optimal well group performance is achieved at a fracture orientation of 45°, beyond which production declines. Increasing well spacing reduces the water cut rise rate and the production decline rate, thereby improving cumulative oil production. However, it leads to a faster production decline in the early development stage. This work could provide theoretical guidance for waterflooding in ultra-low permeability reservoirs. Full article

Oil-contaminated soils represent a significant environmental challenge due to the presence of petroleum hydrocarbons and associated pollutants. At the same time, such materials may contain valuable hydrocarbon-rich organic fractions that can potentially be recovered and reused. In this study, the organic phase extracted from oil-contaminated soil was investigated as a secondary hydrocarbon resource for the production of bitumen-like materials. The extracted organic phase was subjected to thermal oxidation to obtain a bitumen-like material, followed by modification using road bitumen (BND 50/70) and an SBS polymer. The resulting bitumen-like material exhibited improved performance after modification, with the softening point increasing from 32.1 to 40.6 °C, the rotational viscosity from 3.11 to 101.5 Pa·s, and enhanced high-temperature rutting resistance. The structural and compositional characteristics of the obtained materials were analyzed using FTIR spectroscopy, nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), and Saturates, Aromatics, Resins, and Asphaltenes (SARA) fractionation. Physicomechanical and rheological properties were evaluated using penetration, softening point, rotational viscosity, and dynamic shear rheometer (DSR) measurements. The results indicate the presence of aliphatic and aromatic hydrocarbon-rich structures characteristic of petroleum-derived materials. Modification with road bitumen and SBS resulted in redistribution of SARA fractions and improved physicomechanical and rheological properties, including increased softening point, higher viscosity, and enhanced resistance to permanent deformation at elevated temperatures. Overall, the obtained results demonstrate that oil-contaminated soils can be considered a promising secondary source of hydrocarbon-rich raw materials. The proposed approach combines waste remediation with resource recovery and supports the development of sustainable technologies for the utilization of petroleum-containing wastes within a circular economy framework. Full article

In this study, novel and stable cellulose-based oleogels with tunable rheological properties were successfully developed for lubrication applications via cross-linking reactions of epoxidized soybean oil (ESO), microcrystalline cellulose (MCC), and isocyanate. This cross-linking strategy not only overcomes the incompatibility issue arising from the polarity difference between MCC and ESO but also enables precise control over the oleogels’ rheological behavior by tailoring the cross-linking density. The resulting oleogels exhibit excellent thermal stability, with an initial decomposition temperature (T_5%) of approximately 300 °C. Furthermore, oxidation resistance is significantly enhanced with increasing cross-linking density, resulting in a substantial increase in the oxidation induction time (OIT) from 5 to 79 min at 210 °C. Rheological characterization reveals that the oleogels exhibit typical shear-thinning and thixotropic behavior. The plateau modulus ($G_N^0$) exhibits a positive correlation with cross-linking density, accompanied by a simultaneous improvement in structural recovery ability. Tribological tests show that the friction coefficient increases with the cross-linking degree, while four-ball tests indicate that the extreme-pressure load-carrying capacity is governed mainly by the nature of the base oil in addition to the cross-linking density of the gel network. This work provides a promising strategy for the development of high-performance and customizable bio-based lubricating materials. Full article

CO₂ flooding plays a crucial role in enhancing oil recovery (EOR) in heterogeneous reservoirs; however, the reservoir’s vertical rhythmic characteristics and permeability gradients significantly influence the flooding efficiency. Unlike homogeneous reservoirs, CO₂ migration in heterogeneous reservoirs is jointly controlled by gravitational overburden and differences in flow conditions, which can easily lead to gas short-circuiting and the formation of dominant flow paths, thereby reducing the degree of crude oil mobilization. However, systematic research on the mechanisms of CO₂ flooding under different rhythm types and permeability difference remains relatively scarce. In this study, two-dimensional large-scale physical model experiments were conducted using stratified core plates with a planar size of 30 × 30 cm² and a single-layer thickness of 1 cm. The experiments were performed at 70 °C and 18 MPa, corresponding to the target reservoir conditions, with CO₂ injected from the inlet side and outlet pressure controlled by a backpressure valve. Under these conditions, CO₂ remained in the supercritical state during displacement. These experiments were designed to comparatively investigate the effects of reservoir rhythm and permeability contrast on pressure distribution, CO₂ migration patterns, and crude oil mobilization. The study elucidated the mechanisms by which reservoir heterogeneity influences the effectiveness of CO₂ flooding. The results show that the positive rhythmic unit delays upward CO₂ migration and gas breakthrough because of the low-permeability top layer, resulting in the highest ultimate oil recovery of 73.35%. In contrast, the reverse rhythmic unit promotes rapid CO₂ breakthrough through the high-permeability top layer and forms dominant flow paths, causing insufficient mobilization of the middle and bottom layers and yielding the lowest oil recovery of 51.03%. In the sandwich-type rhythmic unit (low–high–low permeability configuration), the interaction between the high-permeability middle layer and gravity override enhances mobilization in the top and middle layers, whereas oil mobilization in the bottom layer remains limited. Under interlayer conditions, increasing the permeability contrast from three-fold to five-fold strengthens preferential flow in the high-permeability layer and reduces oil recovery from 65.58% to 60.99%. Full article

Water-based enhanced oil recovery (EOR) techniques continue to attract interest because of their technical practicality and economic feasibility. Hybrid low-salinity surfactant flooding is a promising EOR strategy for carbonate reservoirs; however, the coupled effects of low-salinity brine, surfactant addition, wettability alteration, electrostatic modification, and capillary pressure reduction remain difficult to isolate. This study investigates hybrid low-salinity surfactant flooding in restored tight carbonate cores using integrated experimental measurements and core-scale numerical modeling. The experimental workflow included oil–water interfacial tension (IFT), zeta potential, contact angle measurements using a custom-designed HPHT imbibition cell, and reservoir-condition HPHT coreflooding under sequential and standalone injection schemes. The sequential flood evaluated the transition from seawater (SW) to 1%diluted seawater (1%dSW) and then to 1%dSW+A-1 surfactant, while standalone floods assessed the direct displacement performance of 1%dSW and 1%dSW+A-1. Dilution from SW to 1%dSW increased IFT from approximately 10.2 to 14.9 mN/m, indicating that the recovery improvement during 1%dSW injection was not caused by IFT reduction. Instead, zeta potential and contact angle results indicated progressive electrostatic modification and wettability alteration toward a less oil-wet state. The contact angle decreased from approximately 123° for SW to 101° for 1%dSW and further to 84° after A-1 addition. In contrast, 1%dSW+A-1 reduced IFT sharply to approximately 0.178 mN/m at 0.2 wt%, lowering the estimated capillary pressure magnitude and weakening capillary trapping. Sequential coreflooding showed that SW recovered 42.65% OOIP, followed by an additional 24.21% OOIP from 1%dSW and 9.11% OOIP from 1%dSW+A-1. Standalone 1%dSW and 1%dSW+A-1 recovered approximately 58.44% and 65.82% OOIP, respectively. Core-scale models reproduced the main recovery and pressure drop trends using zeta potential-guided relative permeability and capillary pressure functions supported by surface complexation modeling concepts. Overall, 1%dSW+A-1 improved oil displacement through a synergistic mechanism in which low-salinity brine stabilized the water film and altered wettability, while A-1 surfactant reduced IFT and weakened capillary trapping. The integrated experimental and modeling workflow provides a mechanistic basis for evaluating hybrid low-salinity surfactant flooding and for linking laboratory-measured interfacial properties to effective core-scale rock–fluid functions. Full article

High-temperature and high-salinity reservoirs (typically referring here to temperatures ≥ 100 °C and salinities > 100 g/L) impose stringent requirements on chemical flooding and profile-control agents, particularly in terms of thermal stability, salt tolerance, injectivity, and environmental compatibility. In this study, a bio-based composite mobility-control and oil-displacement system was developed by combining carbonized corn-straw particles with the biopolymer scleroglucan. Corn-straw biomass particles were prepared by pyrolysis at 500 °C followed by ball milling for 2 h. Their particle-size distribution, elemental composition, and suspension stability were characterized, and the rheological behavior, thermal and salt tolerance, long-term aging stability, injectivity, plugging performance, and enhanced-oil-recovery efficiency of the composite system were evaluated systematically. The average particle size decreased from 25.6 μm for mechanically ground straw to 2.8 μm after carbonization and ball milling. The H/C atomic ratio of the carbonized particles was 0.31, indicating enhanced aromatization and structural stability. A scleroglucan concentration of 1000 ppm provided a suspension rate of 97%, balancing suspension stability and chemical dosage. The composite system maintained stable viscosity and viscoelasticity from 30 to 130 °C in deionized water, saturated NaCl solution, and saturated CaCl₂ solution, with viscosity loss below 10%. After sealed anaerobic aging at 100 °C for 28 days, the viscosity retention remained above 90%. Sand-pack tests showed stable injectivity in media with permeabilities of 1235 and 2064 mD and a plugging efficiency of 95.7% in a 2846 mD model. In oil-displacement experiments, the composite system increased the final recovery factor from 46.6% for scleroglucan flooding alone to 53.3%, corresponding to an additional 6.7 percentage points. These results demonstrate that the carbonized biomass particle-scleroglucan system has promising thermal stability, salt tolerance, plugging capacity, and oil-displacement performance, providing a potential green strategy for mobility control in harsh reservoir environments. Full article