Processes

33 pages, 3735 KB

Open AccessFeature PaperEditor’s ChoiceArticle

Artificial Neural Network-Based Classification of Industrial Sustainability Profiles for Differentiated Fiscal Policy Design in Remanufacturing Processes

by Marta Lilia Eraña-Díaz, Juana Enríquez-Urbano, Beatriz Martínez-Bahena, Jazmin Yanel Juárez-Chávez, Alfonso D’Granda-Trejo and Javier De-la-Rosa-Mondragon

Processes 2026, 14(9), 1501; https://doi.org/10.3390/pr14091501 - 6 May 2026

Viewed by 836

Abstract

The design of differentiated fiscal instruments for industrial sustainability requires robust, data-driven tools capable of capturing the heterogeneity of environmental performance across manufacturing units—a challenge that conventional econometric approaches address only partially, given the non-linear nature of operational–environmental interactions in reconfigurable production systems. [...] Read more.

The design of differentiated fiscal instruments for industrial sustainability requires robust, data-driven tools capable of capturing the heterogeneity of environmental performance across manufacturing units—a challenge that conventional econometric approaches address only partially, given the non-linear nature of operational–environmental interactions in reconfigurable production systems. This study introduces a two-phase computational framework that integrates unsupervised machine learning and supervised classification to generate evidence-based sustainability profiles for fiscal policy targeting. Its principal contribution is the combination of K-Means clustering with a binary artificial neural network (ANN) classifier, operationalized through an accessible decision-support interface that enables differentiated incentive allocation without requiring programming expertise from policymakers. A dataset of 1000 manufacturing records comprising seven operational and technological input variables—material usage, production capacity, reconfiguration time, downtime, AI optimization, IoT connectivity, and predictive maintenance—and three environmental output indicators—energy consumption, carbon emissions, and waste generation—was analyzed. In Phase One, K-Means segmentation with k = 6, selected through multi-criteria convergence (Silhouette = 0.102; Elbow, Davies–Bouldin, and Calinski–Harabasz indices), identified six distinct sustainability profiles with marked environmental differentiation. In Phase Two, a binary ANN classifier (architecture: 7 → 64 → 32 → 1 neurons; ReLU and sigmoid activations) was trained to distinguish the reference cluster C0 (low environmental impact: energy 145.1 kWh, emissions 45.2 CO₂-eq) from the high-impact cluster C1 (emissions 67.8 CO₂-eq, waste 41.5 kg). The trained classifier achieved an overall accuracy of 75.4% and an AUC-ROC of 0.774 on the held-out test set, with a macro-averaged F1-score of 0.753 and a Cohen’s kappa coefficient of 0.508, indicating moderate-to-substantial agreement beyond chance. Class C1 (high-impact establishments) achieved a precision of 0.794 and a recall of 0.730, supporting reliable identification of manufacturing units that would most benefit from targeted fiscal support. The framework is deployed through a Gradio-based graphical interface incorporating a traffic-light sustainability classification (green/yellow/red), enabling direct and interactive application by tax authorities and industrial policymakers. The modular architecture supports adaptation to larger or sector-specific datasets, making it transferable across industrial policy contexts. Full article

(This article belongs to the Special Issue Thermal Engineering: Energy Conversion, Numerical Simulation, and Advanced Control)

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39 pages, 10782 KB

Open AccessArticle

The Effect of Baffle Structure and Rotational Speed on the Flow Field in the Silicon Purification Process via the Rotational Segregation Method: A Water Model Study on Tracer Transport and Concentration Variation

by Zhiren Rong, Dongzhi Hou, Chao Chen, Guoqi Song, Zhuoyue Du, Jiongtong Li, Houyuan Zhang, Wanming Lin, Lei Chen and Guoyu Qian

Processes 2026, 14(9), 1500; https://doi.org/10.3390/pr14091500 - 6 May 2026

Cited by 1 | Viewed by 503

Abstract

This study experimentally investigated, using a water-model hydrodynamic analogue, the effects of crystallizer rotational speed and baffle configuration on the flow-field structure, mass transfer, and mixing behavior inside the crucible of a rotational segregation model system relevant to silicon processing. Three configurations were [...] Read more.

This study experimentally investigated, using a water-model hydrodynamic analogue, the effects of crystallizer rotational speed and baffle configuration on the flow-field structure, mass transfer, and mixing behavior inside the crucible of a rotational segregation model system relevant to silicon processing. Three configurations were examined: no baffle, straight baffles, and inclined baffles. Flow visualization and stimulus–response tracer experiments were conducted at 200 and 300 rpm to compare their effects on the main flow pattern and mixing characteristics. The results showed that, without baffles, a complete annular main flow formed, and the fluid moved downward spirally along the crystallizer wall. Mixing was relatively fast, indicating limited potential for local tracer retention. With straight baffles, the main flow was strongly obstructed and redistributed, and the mixing time in local bottom regions, especially in front of the 90° baffle, was markedly prolonged. This behavior suggested a more favorable hydrodynamic environment for local retention and accumulation in the model system, and the effect was most evident at 200 rpm. With inclined baffles, transport in the upper region was enhanced, whereas bottom flow was weakened. Although the tracer could move downward along the baffle surface, it was rapidly swept away after reaching the bottom, indicating reduced stability of local accumulation. Increasing the rotational speed from 200 to 300 rpm strengthened the overall flow and shortened the mixing time under all conditions. Overall, straight baffles, particularly at 200 rpm, produced the strongest tendency for local retention in the present model system. These results provide preliminary hydrodynamic insight into flow regulation and transport behavior in rotational segregation systems. Full article

(This article belongs to the Special Issue Computational Fluid Dynamics Modeling and Simulation in Material Processing and Metallurgy)

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22 pages, 6898 KB

Open AccessArticle

Optimization of Self-Recirculating Casing Treatment for Centrifugal Compressors with Bent-Pipe Intake

by Jian Sun, Xingyu Liang, Yongdi He, Yonghai Tian and Lianfeng Li

Processes 2026, 14(9), 1499; https://doi.org/10.3390/pr14091499 - 6 May 2026

Viewed by 423

Abstract

Bent-pipe intake distortion restricts the stable flow range (SFR) and degrades the aerodynamic performance of centrifugal compressors. To expand the SFR while minimizing efficiency loss, this study carries out multi-objective optimization on a self-recirculating casing treatment (SRCT). Numerical simulations were performed [...] Read more.

Bent-pipe intake distortion restricts the stable flow range (SFR) and degrades the aerodynamic performance of centrifugal compressors. To expand the SFR while minimizing efficiency loss, this study carries out multi-objective optimization on a self-recirculating casing treatment (SRCT). Numerical simulations were performed at 65,000 rpm based on a four-factor, three-level orthogonal test design, focusing on four key geometric parameters: recirculation angle (α), downstream slot width (b_r), axial passage height (h_b), and axial passage width (b_b). The specific effects of these parameters on the SFR, isentropic efficiency (η), and a comprehensive stability index (ΔSFR/Δη) were systematically analyzed. Three optimal designs were obtained through this optimization approach, tailored to different operational requirements, namely Casing_SFR, Casing_η, and Casing_Opt. The results indicate that the comprehensive optimal model (Casing_Opt) achieves an optimal balance between SFR expansion and efficiency retention, extending the SFR by 28.67% with only a 10.84% reduction in isentropic efficiency. Flow field analysis further verifies that the optimized SRCT can effectively modulate tip leakage flow via low-energy fluid suction and reinjection, correct deviated inlet incidence, thereby mitigating the severe leading-edge flow separation and high-entropy generation induced by distorted inflow. Full article

(This article belongs to the Section Process Control, Modeling and Optimization)

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20 pages, 7364 KB

Open AccessArticle

Optimizing Biodiesel Synthesis: From Process Parameters to the Distinct and Sub-Additive Effects of Water and Iron in Supercritical Methanol

by Ke Zhang, Zhigang Que, Jie Luo, Yinxuan Fu, Xiaodi Cheng, Rong Huang, Fan Gu and Xianhua Qiu

Processes 2026, 14(9), 1498; https://doi.org/10.3390/pr14091498 - 6 May 2026

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Abstract

Biodiesel is a promising green and renewable fuel that can replace fossil fuels and reduce greenhouse gas emissions. The effects of reaction temperature (200–290 °C), residence time (0–75 min), and methanol-to-oleic acid molar ratio (6:1–35:1) on the esterification of oleic acid with supercritical [...] Read more.

Biodiesel is a promising green and renewable fuel that can replace fossil fuels and reduce greenhouse gas emissions. The effects of reaction temperature (200–290 °C), residence time (0–75 min), and methanol-to-oleic acid molar ratio (6:1–35:1) on the esterification of oleic acid with supercritical methanol were investigated in a batch reactor. Furthermore, orthogonal experiments were designed to explore the optimal reaction conditions. and the influences of H₂O (0–33.3 wt%) and Fe (0–20.0 wt%) contents were examined. Results showed that the conversion of oleic acid to methyl oleate exhibited a volcano-type dependence on both temperature and molar ratio, peaking at 250 °C and a ratio of 15:1, respectively. Conversion initially increased with residence time, then plateaued around 30 min. Under the optimal conditions of 250 °C, 30 min, and a 15:1 molar ratio, the conversion reached 76.8%. Both additives enhanced conversion at low loadings (≤5.0 wt%). However, higher water content inhibited conversion, whereas the promotional effect of Fe saturated beyond 5.0 wt%. The co-addition of 5.0 wt% water and 5.0 wt% Fe yielded a positive but sub-additive effects: conversion exceeded that with water alone but remained lower than with Fe alone. These findings contribute to advancing the high-efficiency and low-cost production of biodiesel. Full article

(This article belongs to the Topic Advanced Bioenergy and Biofuel Technologies)

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33 pages, 48606 KB

Open AccessArticle

Experimental Methodology for Thermo-Mechanical Stress Analysis

by Mario Acosta-Flores, Moisés Montiel-González, Mario Limón-Mendoza and Maura Casales-Díaz

Processes 2026, 14(9), 1497; https://doi.org/10.3390/pr14091497 - 6 May 2026

Viewed by 433

Abstract

The experimental analysis of stresses in thermo-mechanical problems is fundamental for the design and evaluation of the mechanical behavior of structures, frames and various machine elements that operate under mechanical and thermal loads. It is also essential for complementing and validating analytical and [...] Read more.

The experimental analysis of stresses in thermo-mechanical problems is fundamental for the design and evaluation of the mechanical behavior of structures, frames and various machine elements that operate under mechanical and thermal loads. It is also essential for complementing and validating analytical and numerical studies. This paper proposes an experimental methodology that allows the determination of plane states of stress—mechanical, thermal, and thermo-mechanical—based on the experimental measurement of thermo-mechanical deformation states at a surface point. Based on the theory of linear mechanical elasticity and applying the principle of superposition, plane thermo-mechanical constitutive models are developed, and methods are proposed that allow the thermal and mechanical variables in the models to be experimentally decoupled. The methodology was validated by thermal, mechanical and thermo-mechanical tests carried out on test specimens made of three materials: steel, aluminum and brass. The results show effectiveness in decoupling and solving the analytical models corresponding to the plane, mechanical, thermal, and thermo-mechanical states of stress. The maximum deviations obtained between the stresses provided by the formulated models and the experimental results were a maximum of 4% in most cases. Full article

(This article belongs to the Special Issue Thermal Engineering: Energy Conversion, Numerical Simulation, and Advanced Control)

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14 pages, 2129 KB

Open AccessArticle

Magnetohydrodynamic Modeling of Arc-Induced Thermal Response and Insulation Ignition Risk in Low-Voltage AC Short-Circuit Faults

by Shuchao Li, Haiyue Zhou, Xin Wang, Yuling Wang, Xian Wu, Jingjing Li, Wentao Jiang, Longnv Li and Gaojia Zhu

Processes 2026, 14(9), 1496; https://doi.org/10.3390/pr14091496 - 6 May 2026

Viewed by 542

Abstract

Low-voltage (LV) alternating current (AC) power distribution systems are widely used, where phase-to-neutral short-circuit faults are a major cause of electrically induced fires. Prior to a circuit breaker interruption, arc discharges may develop between conductors, leading to intense localized heating of the cable [...] Read more.

Low-voltage (LV) alternating current (AC) power distribution systems are widely used, where phase-to-neutral short-circuit faults are a major cause of electrically induced fires. Prior to a circuit breaker interruption, arc discharges may develop between conductors, leading to intense localized heating of the cable insulation and a potential ignition risk. In this study, a magnetohydrodynamic (MHD) model of 220 V AC short-circuit arcs is established to investigate the coupled electrical and thermal behavior of arc discharges and their induced heating effects on conductor insulation. The transient temperature distribution in the arc region and insulation layer is numerically analyzed under different tripping currents and tripping times, and insulation ignition risk is evaluated based on characteristic thermal thresholds. To validate the simulations, a controllable 220 V AC short-circuit experimental platform is developed using a motor-driven wire contact mechanism. Circuit breakers rated at 20 A, 32 A, and 63 A are tested, and short-circuit current and voltage waveforms are recorded. The results indicate that insulation ignition risk is jointly governed by short-circuit current magnitude and breaker tripping time. Delayed interruption significantly increases insulation temperature and ignition susceptibility, whereas rapid interruption effectively suppresses arc-induced heating. Full article

(This article belongs to the Special Issue High-Power-Density and High-Reliability Power Transformers: Design, Operation, Protection, and Enabling Technologies)

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1 pages, 116 KB

Open AccessRetraction

RETRACTED: Luo, Y.; Xiao, Y. A Full-State Reliability Analysis Method for Remanufactured Machine Tools Based on Meta Action and a Markov Chain Using an Exercise Machine (EM) as an Example. Processes 2023, 11, 2794

by Yueping Luo and Yongmao Xiao

Processes 2026, 14(9), 1495; https://doi.org/10.3390/pr14091495 - 6 May 2026

Viewed by 359

Abstract

The journal retracts the article titled “A Full-State Reliability Analysis Method for Remanufactured Machine Tools Based on Meta Action and a Markov Chain Using an Exercise Machine (EM) as an Example” [...] Full article

15 pages, 1946 KB

Open AccessArticle

Effect of Pressure and Surfactants with Different IFT and Wettability Alteration Abilities on Imbibition Oil Recovery in Tight Sandstone Reservoir Under High Pressure

by Tianjiang Wu, Teng Wang, Hong He, Baoqiang Wu, Jiajun Chen and Zhuojun Liu

Processes 2026, 14(9), 1494; https://doi.org/10.3390/pr14091494 - 5 May 2026

Viewed by 426

Abstract

The water huff-n-puff imbibition oil recovery technique has been recognized as an important approach to supplementing formation energy and recovering the remaining oil, attracting increasing attention. To further improve imbibition efficiency, a surfactant-aided huff-n-puff imbibition technique under high pressure was proposed. However, the [...] Read more.

The water huff-n-puff imbibition oil recovery technique has been recognized as an important approach to supplementing formation energy and recovering the remaining oil, attracting increasing attention. To further improve imbibition efficiency, a surfactant-aided huff-n-puff imbibition technique under high pressure was proposed. However, the imbibition mechanisms under high pressure, particularly under variable pressurization modes, remain insufficiently understood. In this study, the effects of different pressurization methods (constant vs. variable pressure) and surfactant types on imbibition behavior were systematically investigated. The results show that, compared with spontaneous imbibition, high-pressure imbibition increases oil recovery by 7–10% and the imbibition rate by 1–2 times, with the variable pressurization mode demonstrating a more pronounced enhancement. Surfactant selection should not pursue ultra-low interfacial tension (IFT) alone; instead, the wettability alteration ability is more critical. An optimal IFT–wettability synergy window is identified, through which the best imbibition performance is achieved when the IFT ranges from 10⁻² to 10⁻¹ mN/m and the contact angle ranges from 30° to 60°. Furthermore, the slug injection mode provides a synergistic effect with high-pressure variable pressurization and surfactant action. Compared with high-pressure formation water imbibition, surfactant-aided imbibition increases oil recovery by 10.44% and the imbibition rate by three times. These findings provide a deeper understanding of the key factors governing imbibition behavior and support the application of surfactant-aided huff-n-puff imbibition under high pressure in tight sandstone reservoirs. Full article

(This article belongs to the Special Issue Advances in Technology for Enhancing Oil and Gas Recovery in Shale Reservoirs (2nd Edition))

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26 pages, 16501 KB

Open AccessArticle

Multi-Parameter Simultaneous Optimization of LDWC-IR Systems Based on the SaDE Algorithm

by Qiuli Zhang, Jiasen He, Huaiyu Zhao, Jing Zhang, Chengbin Shen and Lei Wu

Processes 2026, 14(9), 1493; https://doi.org/10.3390/pr14091493 - 5 May 2026

Viewed by 381

Abstract

The liquid-only transfer dividing wall column (LDWC) eliminates the difficulty of controlling the vapor-phase distribution ratio; however, it involves numerous structural and operating parameters, resulting in high initialization difficulty and convergence challenges. This paper proposes a Matlab-SaDE-Aspen Plus (Aspen Plus V14) framework that [...] Read more.

The liquid-only transfer dividing wall column (LDWC) eliminates the difficulty of controlling the vapor-phase distribution ratio; however, it involves numerous structural and operating parameters, resulting in high initialization difficulty and convergence challenges. This paper proposes a Matlab-SaDE-Aspen Plus (Aspen Plus V14) framework that reformulates the convergence problem through a multi-parameter simultaneous optimization approach, thereby enabling the efficient design of the LDWC. Building upon this framework, two intermediate reboiler intensification schemes (IR-LDWC1 and IR-LDWC2) are proposed based on CGCC analysis, and four key parameters are simultaneously optimized using the Matlab-SaDE-Aspen Plus framework to eliminate the cumulative errors inherent in independent sequential parameter optimization. The results indicate that, compared with conventional distillation sequences, the LDWC achieves reductions of 17.62% in total energy consumption, 19.35% in total annual cost, and 16.53% in CO₂ emissions, with the most significant improvement observed in exergy efficiency. Among the intensified configurations, IR-LDWC2 exhibits the best overall performance, with total energy consumption, TAC, and CO₂ emissions further reduced by 30.15%, 33.17%, and 31.24%, respectively. Full article

(This article belongs to the Section Energy Systems)

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34 pages, 15641 KB

Open AccessArticle

Production and Characterisation of Polyhydroxyalkanoates from Cocoa Mucilage Using a Wild-Type Priestia aryabhattai Strain

by Jimmy Núñez-Pérez, Osmar J. Cornejo-Lucero, Rosario C. Espin-Valladares, Pedro Barba, Hortensia M. Rodríguez Cabrera and José-Manuel Pais-Chanfrau

Processes 2026, 14(9), 1492; https://doi.org/10.3390/pr14091492 - 5 May 2026

Viewed by 797

Abstract

The accumulation of petroleum-based plastics demands sustainable alternatives such as polyhydroxyalkanoates (PHAs), biodegradable polyesters synthesised by numerous prokaryotes. However, high feedstock costs limit their commercialisation. This study evaluated cocoa mucilage, an underutilised by-product of the Ecuadorian cacao sector, as a low-cost carbon source [...] Read more.

The accumulation of petroleum-based plastics demands sustainable alternatives such as polyhydroxyalkanoates (PHAs), biodegradable polyesters synthesised by numerous prokaryotes. However, high feedstock costs limit their commercialisation. This study evaluated cocoa mucilage, an underutilised by-product of the Ecuadorian cacao sector, as a low-cost carbon source for PHA production by a wild-type strain isolated from cocoa fruit residues. Bacteria were recovered from cocoa mucilage and pod shell fractions and screened for PHA accumulation by Sudan Black B staining with UV–Vis spectrophotometric confirmation. A single PHA-positive isolate, designated Priestia aryabhattai strain NBP01-UTN (GenBank accession OR567321.1; 99.88% 16S rRNA gene sequence identity to the type strain B8W22T), was recovered from the cocoa shell surface—representing, to the best of our knowledge, the first report of a PHA-producing P. aryabhattai from cacao fruit residues. Fermentation conditions were optimised using the response surface methodology with a central composite design evaluating temperature, pH, and ammonium sulphate concentration. The fitted quadratic model was highly significant (R² = 0.978, p < 0.0001), indicating that temperature and nitrogen limitation were the dominant factors. Optimal conditions (40 °C, pH 7.30, 0 g·L⁻¹ (NH₄)₂SO₄) yielded 0.496 g·L⁻¹ PHA at 24 h (productivity ≈ 20.7 mg·L⁻¹·h⁻¹). Notably, no external nitrogen supplementation was required, as the endogenous nitrogen in cocoa mucilage sufficed to sustain growth whilst triggering the nutrient imbalance needed for PHA biosynthesis. FTIR and DSC analyses provided spectroscopic and thermal evidence consistent with poly(3-hydroxybutyrate) (PHB), although definitive monomer-level confirmation requires GC–MS or NMR spectroscopy. These results demonstrate the feasibility of coupling a locally isolated wild-type strain with cocoa mucilage to produce bioplastic within a circular bioeconomy framework. Full article

(This article belongs to the Special Issue Recent Advances in Bioprocess Engineering and Fermentation Technology)

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20 pages, 5876 KB

Open AccessArticle

Reaction Kinetics and Process Intensification of Continuous-Flow Synthesis of Propylene Glycol in a Spiral Microchannel Reactor

by Jiahua Li, Yue You, Xiang Qiu, Xiang Zheng, Miaomiao Jin and Haifang Mao

Processes 2026, 14(9), 1491; https://doi.org/10.3390/pr14091491 - 5 May 2026

Viewed by 879

Abstract

This study investigates the continuous-flow hydrolysis reaction of propylene oxide (PO) in a spiral microchannel reactor, integrating experiments, computational fluid dynamics (CFD) simulations, and response surface methodology (RSM). To the best of our knowledge, experimentally determined apparent Arrhenius parameters for PO hydrolysis under [...] Read more.

This study investigates the continuous-flow hydrolysis reaction of propylene oxide (PO) in a spiral microchannel reactor, integrating experiments, computational fluid dynamics (CFD) simulations, and response surface methodology (RSM). To the best of our knowledge, experimentally determined apparent Arrhenius parameters for PO hydrolysis under microscale continuous-flow conditions remain rarely reported, and afterwards they were incorporated into CFD-based numerical simulations. This combined experimental–numerical framework provides a robust methodology for quantifying and optimizing liquid-phase kinetics in microscale flow environments. Subsequently, CFD simulations were employed to examine key process parameters, including reaction system temperature, inlet flow rate, and reactor length. Finally, RSM was utilized to identify the optimal process conditions (reaction system temperature of 298.15 K, inlet flow rate of 6 × 10⁻³ m·s⁻¹, and reactor length of 4 m), achieving a predicted PO conversion rate of 81.68%. The study provides a reference for designing and optimizing spiral microchannel reactors for PO hydrolysis. Full article

(This article belongs to the Section Chemical Processes and Systems)

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15 pages, 1998 KB

Open AccessArticle

Novel Carqueja-Mediated Instant Green Synthesis of AgNPs for an Innovative Mouthrinse

by Giselle Giovanna do Couto de Oliveira, Maurillo de Nez Souza, João Victor Ribeiro Bizarri, Ana Paula Peron, Kassiely Zamarchi, Cristiane Mengue Feniman Moritz and Otávio Akira Sakai

Processes 2026, 14(9), 1490; https://doi.org/10.3390/pr14091490 - 5 May 2026

Viewed by 477

Abstract

According to the National Cancer Institute, approximately 3.9 billion people worldwide suffer from non-communicable oral diseases, with head and neck cancer patients experiencing exacerbated oral mucositis primarily from radiotherapy. This condition manifests as painful, debilitating mucosal lesions, necessitating effective antimicrobial interventions. This study [...] Read more.

According to the National Cancer Institute, approximately 3.9 billion people worldwide suffer from non-communicable oral diseases, with head and neck cancer patients experiencing exacerbated oral mucositis primarily from radiotherapy. This condition manifests as painful, debilitating mucosal lesions, necessitating effective antimicrobial interventions. This study developed and characterized stable mouthwash formulations containing green-synthesized silver nanoparticles (AgNPs) derived from Baccharis trimera (carqueja) extract for the management of oral mucositis, evaluating their physicochemical stability, antimicrobial efficacy, and biosafety. AgNPs formation was confirmed by color change to brown and a surface plasmon resonance band at 407 nm (UV-Vis), with dynamic light scattering revealing a monomodal hydrodynamic diameter of ~25 nm and stable dispersion; scanning electron microscopy showed spherical particles of 25–35 nm. Four formulations (22–85 ppm AgNPs) in a commercial vehicle exhibited excellent stability over 60 days at 5 °C and 25 °C, maintaining near-neutral pH (~7), low surface tension (<5 mN/m), and unchanged spectral profiles, with no phase separation under centrifugation or thermal stress (up to 70 °C). Antimicrobial assays via broth microdilution demonstrated broad-spectrum activity for the 85 ppm formulation: MICs of 125 µg/mL (S. epidermidis, E. faecalis), 62.5 µg/mL (E. coli, P. aeruginosa), and 250 µg/mL (S. aureus), with MBC of 125 µg/mL (bactericidal) against P. aeruginosa; no activity against C. albicans (MIC > 500 µg/mL). Against human oral microbiota (n = 4 volunteers), it reduced bacterial growth by 14–156% relative to controls (e.g., −5% to 156% inhibition). Cytogenotoxicity tests (A. cepa) confirmed non-toxicity (mitotic index 79–93% of control, low cellular alteration index). These findings establish the carqueja-mediated instant green AgNPs mouthwash as a stable, potent antimicrobial agent, poised to mitigate mucositis-related infections and enhance the quality of life of cancer patients. Full article

(This article belongs to the Special Issue Advanced Manufacturing Processes of Composite Materials)

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17 pages, 8667 KB

Open AccessArticle

Evolution of Time-Varying Reservoir Flow Field and Differential Control in the Ultra-High Water Cut Stage: A Case Study of Block 1G, Chengdao Oilfield, China

by Yimo Ma, Yanzhen Wang, Ming Wang, Shu Jiang, Guozheng Ma, Xuexue Jiang, Wenfei Yang and Xuanhe Tang

Processes 2026, 14(9), 1489; https://doi.org/10.3390/pr14091489 - 5 May 2026

Viewed by 486

Abstract

In the ultra-high water cut stage, unconsolidated sandstone reservoirs suffer from severe reservoir property time-variation, streamline solidification, and inefficient water circulation. To tackle these problems, this study takes Chengdao Oilfield Block 1G as an example and establishes a dynamic geological model considering permeability [...] Read more.

In the ultra-high water cut stage, unconsolidated sandstone reservoirs suffer from severe reservoir property time-variation, streamline solidification, and inefficient water circulation. To tackle these problems, this study takes Chengdao Oilfield Block 1G as an example and establishes a dynamic geological model considering permeability time-varying characteristics based on logging, core, and production data. The flow field intensity index and streamline solidification rate are introduced to quantitatively characterize the preferential flow channels and high water-consumption zones. Results show that long-term water flooding increases the average permeability by 26.88% and expands the interlayer permeability ratio from 10.33 to 19.00. The streamline solidification rate reaches 75%, forming obvious “short-circuit” circulation. Three remaining oil enrichment patterns are identified, which are mainly controlled by sedimentary microfacies, structural highs, and well pattern control. A differential regulation strategy including 3D well pattern reconstruction and streamline diversion is proposed. Field prediction indicates that the cumulative incremental oil can reach 410,000 tons and the recovery factor is enhanced by 1.3%. This study not only reveals the dynamic evolution mechanism of flow field under water-rock coupling effects but also provides a practical technical system for flow field regulation and remaining oil tapping in similar offshore ultra-high water-cut unconsolidated sandstone reservoirs. Full article

(This article belongs to the Special Issue Numerical Simulation and Application of Flow in Porous Media)

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25 pages, 1905 KB

Open AccessArticle

Decision-Making for Secure and Stable Operation of Power Systems: A Multi-Scenario-Based Optimization Model

by Liang Guo, Ziping Peng, Junjie Zhang, Yi Zheng and Shufang Zhou

Processes 2026, 14(9), 1488; https://doi.org/10.3390/pr14091488 - 5 May 2026

Viewed by 498

Abstract

In practical power system operation scenarios, extreme natural weather conditions and fluctuations at both the supply and demand sides pose significant challenges to the stable operation and the formulation of operational decision-making for power systems. Particularly in extreme scenarios involving faults, it may [...] Read more.

In practical power system operation scenarios, extreme natural weather conditions and fluctuations at both the supply and demand sides pose significant challenges to the stable operation and the formulation of operational decision-making for power systems. Particularly in extreme scenarios involving faults, it may lead to power supply–demand imbalances and instability in the power system. To address this issue, this paper proposes a decision-making approach for the secure and stable operation of power systems using a multi-scenario-based optimization model. Initially, a joint scenario set is generated using historical operational data to accurately depict multiple complex scenarios. Building on this, a multi-scenario-based optimization model is constructed, with responses facilitated by flexible adjustment resources within the system. Considering the non-convex and nonlinear characteristics of the model, an improved Harris Hawks Optimization (HHO) algorithm is employed to search for the global optimal solution. Finally, a modified IEEE-33 bus test system is utilized to demonstrate the feasibility and effectiveness of the proposed method. Full article

(This article belongs to the Special Issue AI-Driven Innovations for Enhancing Power System Stability and Operational Efficiency)

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21 pages, 6192 KB

Open AccessArticle

Composition and Structure Characteristics and Thermal Conversion Performance of Fly Ash from Zhundong Coal Fired Process

by Wei-Dong Gao, Wen-Long Mo, Xiao-Qin Yang, Wei-Qiang Yang, Ya-Ya Ma, Gui-Han Zhao, Shu-Pei Zhang and Zhi-Qiang Yang

Processes 2026, 14(9), 1487; https://doi.org/10.3390/pr14091487 - 5 May 2026

Cited by 2 | Viewed by 556

Abstract

Fly ash (FA) from Zhundong coal combustion features high alkali/calcium content and a low Si/Al ratio, limiting its potential for conventional utilization. To enable its high-value application, six size-fractionated samples (FA1–FA6) were characterized via laser particle sizing, SEM-EDS, XRF, XRD, FT-IR, and TGA, [...] Read more.

Fly ash (FA) from Zhundong coal combustion features high alkali/calcium content and a low Si/Al ratio, limiting its potential for conventional utilization. To enable its high-value application, six size-fractionated samples (FA1–FA6) were characterized via laser particle sizing, SEM-EDS, XRF, XRD, FT-IR, and TGA, to elucidate particle-size-dependent physicochemical and thermal properties. The results show that the size distribution centered at 48–150 μm (~71%). With decreasing size, the morphology shifted from irregular aggregates to smooth vitreous spheres. The chemical composition exhibits significant elemental segregation; the SiO₂ content decreases with decreasing particle size, while active components such as CaO, MgO, and Fe₂O₃ are significantly enriched in fine particles. The thermal conversion behavior is regulated by particle size: The combustion reaction under an air atmosphere conforms to the second-order kinetic model, with the activation energy decreasing from 192.73 kJ·mol⁻¹ for coarse particles (>150 μm) to 63.53 kJ·mol⁻¹ for fine particles (<43 μm); under a nitrogen atmosphere, the weight loss originates from the removal of structural water and the decomposition of carbonates, and fine particles exhibit a higher pyrolysis activation energy (504.15 kJ·mol⁻¹) in the high-temperature stage (850–940 °C) due to being rich in high-crystallinity carbonates. The results of this study elucidate the structure–activity relationship of “particle size-composition-activity” for Zhundong coal fly ash and propose a graded utilization scheme where coarse fractions are suitable for low-grade building fillers, while fine fractions can be used as feedstocks for coal pyrolysis catalysts and functional adsorbents, providing a theoretical basis for its targeted resource utilization based on particle size fractionation. Full article

(This article belongs to the Section Chemical Processes and Systems)

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18 pages, 12863 KB

Open AccessArticle

Study on the Preparation and Application of Channel-Type High-Efficiency Filter Paper

by Mingyu Li, Desheng Wang, Lingyun Wang, Yuhan Wang, Jinhao Xie, Yun Liang, Jian Kang and Hao Wang

Processes 2026, 14(9), 1486; https://doi.org/10.3390/pr14091486 - 5 May 2026

Viewed by 672

Abstract

Air pollution has drawn increasing attention. The channel-type structure, as an ideal energy-saving and resistance-reducing strategy for air filters, can effectively lower filtration resistance. However, current commercial channel-type filters generally exhibit only medium or low filtration efficiency, and the use of plant fibers [...] Read more.

Air pollution has drawn increasing attention. The channel-type structure, as an ideal energy-saving and resistance-reducing strategy for air filters, can effectively lower filtration resistance. However, current commercial channel-type filters generally exhibit only medium or low filtration efficiency, and the use of plant fibers as raw material limits their application in high-efficiency filters. In this study, high-efficiency glass fiber filter paper was combined with a channel-type structure, and the formulation and processing techniques suitable for the channel-type design were systematically investigated, leading to the fabrication of channel-type high-efficiency filters. The optimal formulation was determined to be a blend of glass wool fibers and 6 mm Tencel fibers in a 6:4 ratio, coated with a thermosetting resin, which yielded filter paper suitable for wave-pleating. The resulting filter paper demonstrated a filtration efficiency of 99.9624%, a pressure drop of 265.6 Pa, and a pleat aspect ratio of 0.209. Using this formulation, pilot-scale filter paper was produced and wave-pleated under processing conditions including a roller speed of 5 m/min, a roller gap of 0.4 mm, and a roller temperature of 160 °C, which was then used to fabricate channel-type high-efficiency filters. The finished channel-type filters achieved a filtration efficiency of 99.9940% with a pressure drop of 164.0 Pa. Compared to traditional pleated filters of the same volume and efficiency rating, the channel-type filter exhibited a 49.53% larger filtration area, a 33.13% lower face velocity, and a 31.67% reduction in pressure drop. This work offers a novel approach to reducing resistance and enhancing efficiency in air filtration systems. Full article

(This article belongs to the Section Materials Processes)

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51 pages, 20413 KB

Open AccessReview

Membrane Reactors for Plastic and Biomass Waste Valorization: A Critical Review

by M. Jafari, A. Andarz, G. Bagnato and K. Ghasemzadeh

Processes 2026, 14(9), 1485; https://doi.org/10.3390/pr14091485 - 4 May 2026

Cited by 1 | Viewed by 696

Abstract

The rapid accumulation of plastic and biomass waste has emerged as a major environmental and resource management challenge, driven by increasing global consumption, low recycling efficiency, and the long-term persistence of waste in natural ecosystems. Conventional valorization routes such as pyrolysis, gasification, reforming, [...] Read more.

The rapid accumulation of plastic and biomass waste has emerged as a major environmental and resource management challenge, driven by increasing global consumption, low recycling efficiency, and the long-term persistence of waste in natural ecosystems. Conventional valorization routes such as pyrolysis, gasification, reforming, and fermentation provide promising pathways for converting waste into fuels and chemicals, yet their industrial deployment remains constrained by thermodynamic limitations, tar formation, catalyst deactivation, high energy demand, and complex downstream separation requirements. Despite increasing research activity, a comprehensive review that systematically addresses membrane reactor (MR) mechanisms, configurations, and their specific applications in the valorization of both plastic and biomass waste remains lacking in the current literature. In recent years, MR technology has attracted increasing attention as a platform for process intensification, integrating reaction and selective separation within a single unit. By enabling in situ product removal, MRs shift reaction equilibria toward higher conversion, selectivity improvement, and a reduction in separation severity and overall energy consumption. This critical review provides a unified and systematic assessment of MR technologies for the valorization of plastic and biomass waste. Reactor configurations, membrane materials, transport mechanisms, and catalytic systems are comprehensively examined, with particular emphasis on hydrogen-selective, oxygen-permeable, and water-selective membranes and their roles in reforming, tar mitigation, and syngas upgrading. The techno-economic and environmental implications of MR integration are critically discussed, together with current technology readiness levels (TRLs) and scale-up challenges. Overall, this review highlights MRs as a versatile and enabling platform for next-generation waste-to-value technologies and outlines their potential role in supporting the transition toward circular, low-carbon fuel and chemical production. Full article

(This article belongs to the Special Issue Process Intensification, Multiscale Simulation, and Optimization in Membrane Reactor Engineering)

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27 pages, 8335 KB

Open AccessArticle

Coupling Control of Depositional Compositions and Diagenesis on Reservoir Quality of Tight Sandstones in Fuyu Oil Layer, Gulong Sag, Songliao Basin

by Xinyu Jiang, Nengwu Zhou, Junhui Li, Fangju Chen, Qiang Zheng, Jie Li, Zhong Chu, Kerou Yang, Guoqiang Ju, Wenbiao Li, Guohui Chen, Pengfei Zhang and Shuangfang Lu

Processes 2026, 14(9), 1484; https://doi.org/10.3390/pr14091484 - 4 May 2026

Viewed by 419

Abstract

Recent exploration highlights the Gulong Sag as a promising target for tight oil in the Fuyu oil layer. However, the distribution of high-quality reservoirs remains poorly understood due to complex depositional and diagenetic controls, posing significant exploration risks. To address this, this study [...] Read more.

Recent exploration highlights the Gulong Sag as a promising target for tight oil in the Fuyu oil layer. However, the distribution of high-quality reservoirs remains poorly understood due to complex depositional and diagenetic controls, posing significant exploration risks. To address this, this study integrates petrological, mineralogical, and pore structure analyses to elucidate the genetic mechanisms of reservoir quality and identify favorable exploration targets. The sandstones are predominantly fine-grained lithic arkoses and feldspathic litharenites, characterized by abundant volcanic lithic clasts and muddy matrix. Four diagenetic facies were identified based on diagenetic assemblages and pore evolution. The chlorite pore-lining facies and moderate compaction–dissolution facies exhibit the highest reservoir quality (avg. porosity of 10.42% and 9.79%, respectively), benefiting from chlorite coatings that inhibited quartz overgrowth and intense dissolution that created secondary porosity. In contrast, the tightly compacted facies and carbonate-cemented facies represent unfavorable reservoirs (avg. porosity of 7.02% and 6.17%, respectively) due to the occlusion of pore throats by muddy matrix and early carbonate cements, respectively. The distribution of these facies is governed by the coupling of sedimentary environment and diagenetic alteration. Benefiting from superior sedimentary conditions and proximity to source rocks, the first member of the Fuyu oil layer developed extensive favorable facies (chlorite pore-lining facies and moderate compaction–dissolution facies), making it the primary exploration target. This study demonstrates how depositional compositions and diagenetic processes jointly control reservoir quality in tight sandstones, providing important insights for the exploration of analogous tight oil reservoirs. Full article

(This article belongs to the Section Petroleum and Low-Carbon Energy Process Engineering)

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13 pages, 11400 KB

Open AccessArticle

Thermal-Mismatch-Related Residual Stress Analysis and Reliability-Oriented Curing Process Improvement of Encapsulated Windings for Dry-Type Transformers

by Haibin Zhou, Jun Deng, Gaojia Zhu, Xiangjiang Yang, Xingzi Liu, Zhicheng Xie, Heng Wu and Dingguo Cai

Processes 2026, 14(9), 1483; https://doi.org/10.3390/pr14091483 - 4 May 2026

Viewed by 607

Abstract

Epoxy encapsulation is widely used in dry-type transformer windings to improve insulation performance and mechanical robustness. However, significant thermo-mechanical residual stresses can be introduced during curing and cooling due to material property mismatch, leading to cracking and reliability concerns. This study aims to [...] Read more.

Epoxy encapsulation is widely used in dry-type transformer windings to improve insulation performance and mechanical robustness. However, significant thermo-mechanical residual stresses can be introduced during curing and cooling due to material property mismatch, leading to cracking and reliability concerns. This study aims to quantitatively analyze the evolution of thermal-mismatch-related residual stress in epoxy-encapsulated windings and to develop a reliability-oriented improved curing process. A representative encapsulated winding structure and a conventional industrial curing schedule are first modeled, and the evolution of the epoxy degree of cure is calculated based on curing kinetics. The obtained cure history is then coupled with a transient thermo-mechanical finite-element model that incorporates cure-dependent material properties to evaluate the residual stress distribution. The simulation results indicate pronounced stress concentration in specific regions of the encapsulation, which corresponds well with typical cracking locations observed in practice, demonstrating the validity of the proposed approach. Based on this model, several modified curing temperature profiles are further investigated to clarify the effects of temperature levels and dwell times on the development of residual stress. Finally, a reliability-oriented curing process improvement is identified, which effectively reduces stress concentration and mitigates cracking while maintaining adequate curing reliability. Full article

(This article belongs to the Special Issue High-Power-Density and High-Reliability Power Transformers: Design, Operation, Protection, and Enabling Technologies)

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16 pages, 2897 KB

Open AccessArticle

Separation, Purification, Basic Structural Characterization and Oxidative Stress Protective Effects of Polysaccharides from Fruitless Wolfberry Bud Tea Against H₂O₂-Induced Damage in SH-SY5Y Cells

by Yanjun Li, Tian Wang, Han Liu, Na Zhang and Ziping Zhang

Processes 2026, 14(9), 1481; https://doi.org/10.3390/pr14091481 - 3 May 2026

Viewed by 484

Abstract

This study optimized the extraction, purification, and structural chemical characterization of polysaccharides from fruitless wolfberry bud tea (FWP), and evaluated their antioxidant activities against H₂O₂-induced oxidative damage in SH-SY5Y cells. Crude FWP was obtained by ultrasonic-assisted water extraction followed [...] Read more.

This study optimized the extraction, purification, and structural chemical characterization of polysaccharides from fruitless wolfberry bud tea (FWP), and evaluated their antioxidant activities against H₂O₂-induced oxidative damage in SH-SY5Y cells. Crude FWP was obtained by ultrasonic-assisted water extraction followed by ethanol precipitation. An orthogonal experiment was conducted to optimize decolorization using D301G macroporous resin, achieving a decolorization rate of 74%, a polysaccharide retention rate of 85%, and a protein removal rate of 61%. Two main purified polysaccharide fractions, FWP-1 (52.3 kDa) and FWP-2 (9.95 kDa), were isolated by DEAE-52 and Sephadex G-150 chromatography. Structural analysis revealed that FWP-1 was a neutral heteropolysaccharide rich in glucose and galactose, while FWP-2 was an acidic polysaccharide with a high content of galacturonic acid. In H₂O₂-induced SH-SY5Y cells, both polysaccharides significantly enhanced cell viability, increased superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) levels, reduced lactate dehydrogenase (LDH) leakage and malondialdehyde (MDA) content, scavenged excessive reactive oxygen species (ROS), and maintained mitochondrial membrane potential. FWP-2 exhibited stronger ROS-scavenging capacity than FWP-1. This study established reliable methods for the purification and characterization of FWP, and verified their potential as natural antioxidants against neuronal oxidative injury. Full article

(This article belongs to the Special Issue Analytical Methodologies and Stability Assessment of Bioactive Compounds in Complex Matrices)

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31 pages, 53177 KB

Open AccessArticle

Study on the Characteristics of Gas–Liquid Two-Phase Flow in Shale Gas Horizontal Wells—Taking Changning Block as an Example

by Xu Zhang, Zisong Huang, Chang Zhang, Qi Wang, Weihua Liu, Zikui Qin and Zhongyi Fan

Processes 2026, 14(9), 1482; https://doi.org/10.3390/pr14091482 - 2 May 2026

Viewed by 599

Abstract

At present, more than 50% of the horizontal wells in Changning block have entered the middle and late stage of low gas production, and the gas is difficult to produce with liquid. For such gas wells with a complex wellbore structure, multiple wellbore [...] Read more.

At present, more than 50% of the horizontal wells in Changning block have entered the middle and late stage of low gas production, and the gas is difficult to produce with liquid. For such gas wells with a complex wellbore structure, multiple wellbore flow patterns and complex pressure distribution, the corresponding gas–liquid distribution characteristics and liquid carrying capacity are not yet mature. Therefore, based on the establishment of a large-scale experimental simulation device for air–water two-phase flow in horizontal wells with a horizontal section–inclined section–vertical section, this paper studies the gas–liquid distribution characteristics and liquid carrying capacity of shale gas horizontal wells through gas–liquid two-phase flow experiments. The variation and distribution characteristics of gas–liquid two-phase flow pattern in horizontal wellbore are mastered. When the gas flow rate in the horizontal section is less than 20 m³/h, and the gas flow rate in the vertical section and the deflecting section is less than 30 m³/h, churn flow occurs and effusion occurs. It is found that the deflecting section of each well section is the most difficult to carry liquid, and the horizontal section is the easiest to carry liquid. When the critical carrying liquid is in the horizontal section, the vertical tube accumulates liquid, and the oblique section accumulates liquid simultaneously. This result is not only crucial to improve the production of gas wells in Changning block but also provide guidance for the production of shale gas horizontal wells in the middle and late low gas production stages. Full article

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16 pages, 1952 KB

Open AccessArticle

The Influence of Cellulose Fiber Content on the Mechanical Properties of Composites Based on Modified Thermoplastic Starch

by Mariusz Fabijański and Jacek Garbarski

Processes 2026, 14(9), 1480; https://doi.org/10.3390/pr14091480 - 2 May 2026

Cited by 1 | Viewed by 796

Abstract

This study presents the results of evaluating composites based on modified thermoplastic starch (TPS) with BWW40 and FD600/30 cellulose fibers at varying mass contents. The aim of this study was to assess the effect of filler type and quantity on mechanical properties and [...] Read more.

This study presents the results of evaluating composites based on modified thermoplastic starch (TPS) with BWW40 and FD600/30 cellulose fibers at varying mass contents. The aim of this study was to assess the effect of filler type and quantity on mechanical properties and water absorption. Test samples were prepared using the injection molding method. It was shown that increasing fiber content led to a reduction in strength of approximately 36% for BWW40 fibers and approximately 37% for FD600/30 fibers at maximum fill. Similar results were observed for elongation at break. Young’s modulus increased by approximately 15% for BWW40 fibers and approximately 13% for FD600/30 fibers. Water absorption also increased with increasing fiber content, which is due to the hydrophilic nature of both the starch matrix and the reinforcing phase. The main conclusion drawn from the conducted research is that by properly selecting the type and content of fibers, it is possible to consciously shape the stiffness and dimensional stability of such composites while maintaining their biodegradability. The results obtained allow for a better assessment of the application potential of these materials in the context of developing sustainable material solutions. Full article

(This article belongs to the Section Materials Processes)

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33 pages, 13339 KB

Open AccessArticle

Modeling and Optimization of Transient Wellbore Temperature in Shale Oil Horizontal Wells Considering Variable Fluid Property and Multi-Source Heat Generation

by Wenming Li, Feng Lu, Xu Du, Dali Zhang, Wenjie Jia and Zhengming Xu

Processes 2026, 14(9), 1479; https://doi.org/10.3390/pr14091479 - 2 May 2026

Cited by 2 | Viewed by 566

Abstract

Reliable characterization of the wellbore temperature field is essential for ensuring drilling safety and optimizing operational parameters in shale oil horizontal wells. To address the limitations of conventional models that assume constant thermophysical properties and neglect interactions among multiple heat sources, a transient [...] Read more.

Reliable characterization of the wellbore temperature field is essential for ensuring drilling safety and optimizing operational parameters in shale oil horizontal wells. To address the limitations of conventional models that assume constant thermophysical properties and neglect interactions among multiple heat sources, a transient heat transfer model featuring one-dimensional heat transfer in the wellbore and two-dimensional heat transfer in the formation is developed. The model uniquely accounts for variable thermophysical properties along with three internal heat sources: bit–rock interaction heat (BRIH), viscous dissipation heat (VDH), and drillpipe–formation friction heat (DFFH). The governing equations are implemented numerically using a fully implicit finite-difference approach and verified against field measurements from 10 wells in the Shengli Oilfield. The model demonstrates high predictive accuracy, with an average relative error of 1.58%. VDH contributes significantly to wellbore temperature elevation (≈3.33 °C), whereas BRIH and DFFH exert comparatively minor effects (≈0.34 °C). Sensitivity analysis shows that geothermal gradient is the dominant factor controlling BHCT (correlation coefficients: 0.74 for OBDF; 0.65 for WBDF), followed by drilling fluid density, with all parameters exhibiting weak intercorrelations. Furthermore, a PSO-RBF optimization framework is developed, reducing computation time from 48.34 min per evaluation to an average of 9.0 min per well (81.4% efficiency improvement) while maintaining high prediction accuracy. Overall, this study contributes theoretical understanding and practical value to temperature prediction and parameter optimization in shale oil horizontal well drilling. Full article

(This article belongs to the Special Issue Oil and Gas Well Engineering: Experimental and Numerical Investigation, 2nd Edition)

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24 pages, 6005 KB

Open AccessArticle

An Improved Wind Power Prediction via a Novel Wind Ramp Identification Algorithm

by Xiong Xiong, Yifan Xu, Tianyu Tao, Yu Huang and Xiaoling Ye

Processes 2026, 14(9), 1478; https://doi.org/10.3390/pr14091478 - 2 May 2026

Viewed by 554

Abstract

Accurate wind power prediction during ramp events remains challenging due to wind speed volatility. This study proposes a hybrid forecasting framework combining improved variational mode decomposition (VMD), a novel ramp factor (RF), and the Informer model. First, a dynamic adaptive VMD method is [...] Read more.

Accurate wind power prediction during ramp events remains challenging due to wind speed volatility. This study proposes a hybrid forecasting framework combining improved variational mode decomposition (VMD), a novel ramp factor (RF), and the Informer model. First, a dynamic adaptive VMD method is employed to filter noise and identify abrupt wind speed changes. Subsequently, a similar period matching algorithm, enhanced by the RF and wind speed similarity coefficients, captures historical convergence features. Finally, the Informer network fuses these features with NWP data. Experimental results demonstrate that the proposed method significantly outperforms existing models in accuracy during ramp events, enhancing grid stability. Full article

(This article belongs to the Section Energy Systems)

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24 pages, 758 KB

Open AccessReview

Towards Sustainable Green Methane: A Review of Catalysis, Process Engineering, and Artificial Intelligence Applications

by Zekun Liu, Jiaze Ma and Yufei Wang

Processes 2026, 14(9), 1477; https://doi.org/10.3390/pr14091477 - 2 May 2026

Viewed by 1199

Abstract

Global energy de-fossilization requires scalable solutions for extended energy storage and industrial emission reduction. Synthesizing green methane via Power-to-Gas technology offers a viable pathway to store renewable electricity while utilizing captured carbon dioxide. This review evaluates recent advancements in catalytic mechanisms, reactor engineering, [...] Read more.

Global energy de-fossilization requires scalable solutions for extended energy storage and industrial emission reduction. Synthesizing green methane via Power-to-Gas technology offers a viable pathway to store renewable electricity while utilizing captured carbon dioxide. This review evaluates recent advancements in catalytic mechanisms, reactor engineering, artificial intelligence applications, and techno-economic and life cycle assessments of green methane production systems. Analysis shows that advanced reactor configurations effectively manage the exothermic heat of the Sabatier reaction. Furthermore, integrating machine learning algorithms accelerates catalyst discovery and enables dynamic process control under fluctuating renewable energy loads. Economic and environmental assessments indicate that the sustainability of green methane depends strictly on utilizing renewable electricity and sourcing non-fossil carbon. Commercial deployment must focus on improving catalyst stability during transient operations and implementing digital twins to establish green methane as a sustainable carbon backbone for chemical industries. Full article

(This article belongs to the Special Issue Feature Review Papers in Section "Chemical Processes and Systems")

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24 pages, 3721 KB

Open AccessArticle

Intelligent Intermittent Production Optimization for Low-Permeability Reservoirs: A Hybrid Physics-Constrained Machine Learning Approach with Dual-Curve Intersection Control

by Jinfeng Yang, Guocheng Wang, Jingwen Xu, Heng Zhang, Xiaolong Wang, Zhangying Han and Gang Hui

Processes 2026, 14(9), 1476; https://doi.org/10.3390/pr14091476 - 1 May 2026

Viewed by 600

Abstract

The efficient development of low-permeability reservoirs is critically constrained by severe geological heterogeneity, marginal permeability (<10 mD), and the consequent prevalence of low-productivity wells. Conventional intermittent production management, reliant on empirical fixed-cycle schedules, fails to adapt to dynamic reservoir behavior and wellbore conditions, [...] Read more.

The efficient development of low-permeability reservoirs is critically constrained by severe geological heterogeneity, marginal permeability (<10 mD), and the consequent prevalence of low-productivity wells. Conventional intermittent production management, reliant on empirical fixed-cycle schedules, fails to adapt to dynamic reservoir behavior and wellbore conditions, leading to suboptimal energy efficiency and recovery. This study presents a physics-constrained, data-driven framework for adaptive intermittent production optimization, specifically designed to address the coupled geological-engineering complexities of such reservoirs. The methodology integrates three core innovations: (1) a hybrid flowing bottomhole pressure (FBHP) decline model coupling a “Three-Segment” wellbore pressure calculation with inflow performance relationship (IPR) curves, enabling dynamic characterization of pressure depletion; (2) a shut-in pressure buildup prediction framework combining a physically interpretable dual-exponential recovery mechanism—representing near-wellbore elastic expansion and far-field formation recharge—with a Random Forest Regression algorithm to capture the influence of geological and operational heterogeneity; and (3) a “Dual-Curve Intersection Method” that autonomously determines optimal pumping and shut-in durations by intersecting predicted pressure decline and recovery curves under geological constraints. Field implementation on 15 low-production wells in the Jiyuan Oilfield—a representative low-permeability asset—demonstrated robust performance: average pump efficiency improved from 14.3% to 14.49%, and average single-well electricity savings reached 15.61%. This work establishes a closed-loop intelligent control framework that bridges reservoir geology, wellbore hydraulics, and machine learning, offering a scalable solution for enhancing energy efficiency and production sustainability in low-permeability and unconventional resources. Full article

(This article belongs to the Section Petroleum and Low-Carbon Energy Process Engineering)

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23 pages, 6926 KB

Open AccessArticle

Polyethersulfone/Attapulgite Membranes Obtained by Solvent Evaporation for Water Vapor Permeation Control

by Bruna Aline Araujo, Rafael Agra Dias, Pamela Thainara Vieira da Silva, Rene Anisio da Paz, Vanessa da Nobrega Medeiros, Carlos Bruno Barreto Luna, Renate Maria Ramos Wellen, Luiz Antônio Pessan and Edcleide Maria Araújo

Processes 2026, 14(9), 1475; https://doi.org/10.3390/pr14091475 - 1 May 2026

Viewed by 491

Abstract

This study investigates the development of mixed matrix membranes based on polyethersulfone incorporated with attapulgite for gas separation applications, addressing the existing gap regarding the use of this mineral in dense membranes obtained exclusively by solvent evaporation and its combined effects on microstructure [...] Read more.

This study investigates the development of mixed matrix membranes based on polyethersulfone incorporated with attapulgite for gas separation applications, addressing the existing gap regarding the use of this mineral in dense membranes obtained exclusively by solvent evaporation and its combined effects on microstructure and transport. The membranes were prepared by phase inversion via solvent evaporation, using solvent/polymer ratios of 75/25 and 80/20 and a thickness of 0.25 mm. The solutions were evaluated in terms of viscosity, and the membranes were characterized by structural techniques such as X-ray diffraction (XRD), atomic force microscope (AFM), contact angle, mechanical properties (tensile testing), and water vapor permeation. The results showed that attapulgite incorporation promoted a reduction in surface roughness (up to ~40%) and a decrease in contact angle (from ~89° to ~68°), indicating increased hydrophilicity. In addition, water vapor permeability was influenced in a non-linear manner, with optimized performance observed at 3 wt% filler loading. Solution viscosities remained within ranges suitable for processing. Structural analyses indicated compatibility between the phases, while morphology changes dependent on filler content were decisive for transport behavior. It is concluded that attapulgite is a promising additive for fine-tuning membrane properties, enabling optimization of the sorption–diffusion balance and improvement of membrane performance in separation applications. Full article

(This article belongs to the Special Issue Sustainable Materials for Energy Industry: High-Temperature Polymer Nanocomposites)

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12 pages, 642 KB

Open AccessArticle

Direct Comparison of Tributyl Phosphate Against Monoamide Extractants in Uranium and Nitric Acid Systems for Solvent Extraction

by Addyson Barnes, Kevin Lyon, Hayden West and Haiyan Zhao

Processes 2026, 14(9), 1474; https://doi.org/10.3390/pr14091474 - 1 May 2026

Viewed by 616

Abstract

Interest in improved disposal pathways and proliferation-resistant systems for used nuclear fuel recycling has driven research on monoamide extractants. Existing comparisons against the industry standard, tributyl phosphate (TBP), emphasize a fundamental approach and span a wide range of test conditions. This work narrows [...] Read more.

Interest in improved disposal pathways and proliferation-resistant systems for used nuclear fuel recycling has driven research on monoamide extractants. Existing comparisons against the industry standard, tributyl phosphate (TBP), emphasize a fundamental approach and span a wide range of test conditions. This work narrows that range and addresses process-scale considerations by presenting hydrodynamic performance results alongside extraction capacity at optimized conditions. The monoamide solvents, 1.0 M DEHiBA (N,N-di(2-ethylhexyl)isobutanamide), 1.5 M DEHBA (N,N-di(2-ethylhexyl)butanamide), and 1.5 M DEHDMPA (N,N-di(2-ethylhexyl)-2,2-dimethylpropanamide), are compared to 1.1 M TBP in bench-scale extraction tests with nitric acid (2–6 M) and uranium (∼0.8 M). Performance is assessed with distribution ratios and dispersion number ratings and supported by specific gravity and viscosity measurements. DEHBA and DEHDMPA exhibited inadequate coalescence behavior with failed or poor dispersion ratings despite uranium distribution ratios of 2.06 ± 0.03 and 0.86 ± 0.01 at O/A = 1.9, limiting suitability for process application. TBP and DEHiBA maintained adequate dispersion ratings across all conditions tested, with maximum distribution ratios of 4.37 ± 0.08 at O/A = 2.6 and 0.67 ± 0.01 at O/A = 2.9, respectively. Higher viscosity values for DEHBA (5.21 cP ± 0.3%) and DEHDMPA (6.53 cP ± 0.4%) relative to TBP (2.04 cP ± 0.4%) and DEHiBA (3.18 cP ± 0.4%) correlate with observed coalescence deficiencies. The methods presented in this work demonstrate the significance of evaluation beyond extraction capacity. Full article

(This article belongs to the Section Chemical Processes and Systems)

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35 pages, 5845 KB

Open AccessReview

Single-Atom Catalysts for Fuel-Cell Cathodes: Atomic-Level Design, Mechanistic Insights, and Practical Challenges

by Yellatur Chandra Sekhar and Sungbo Cho

Processes 2026, 14(9), 1473; https://doi.org/10.3390/pr14091473 - 1 May 2026

Cited by 3 | Viewed by 714

Abstract

The cathodic oxygen reduction reaction (ORR) remains a major kinetic barrier to high-efficiency proton exchange membrane fuel cells (PEMFCs), motivating the search for electrocatalysts that combine high activity, low metal usage, and long-term durability. This review examines single-atom catalysts (SACs) as an emerging [...] Read more.

The cathodic oxygen reduction reaction (ORR) remains a major kinetic barrier to high-efficiency proton exchange membrane fuel cells (PEMFCs), motivating the search for electrocatalysts that combine high activity, low metal usage, and long-term durability. This review examines single-atom catalysts (SACs) as an emerging platform for fuel-cell cathodes with particular emphasis on how atomic-level design, ORR mechanism, and practical deployment barriers are interrelated. The review discusses the key ORR pathways, intermediate binding principles, and scaling constraints that govern cathodic performance, and examines how metal-center selection, coordination-environment engineering, support regulation, synergistic multi-site construction, and morphology-controlled synthesis can be used to tune intrinsic activity and stabilize isolated active sites. It further highlights mechanistic insights from theoretical and operando studies, with emphasis on structure–activity relationships, dynamic active-site evolution, and approaches to mitigate scaling limitations. Major barriers to practical deployment, including carbon corrosion, demetalization, agglomeration, peroxide/reactive oxygen species attack, and the persistent gap between half-cell metrics and membrane electrode assembly performance, are also critically assessed. Rather than treating these topics separately, this review discusses them as connected factors that together determine the viability of SAC-based fuel-cell cathodes. Full article

(This article belongs to the Special Issue Recent Advances in Industrial Applications of Photo/Electrocatalysis)

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19 pages, 1684 KB

Open AccessArticle

Hydrogen Production from Agro-Industrial Residues of the Wine Industry: A Techno-Economic Analysis

by Enrico Sola, Niccolò Fantasia, Marco Puglia, Nicolò Morselli, Giulio Allesina, Paolo Tartarini and Simone Pedrazzi

Processes 2026, 14(9), 1472; https://doi.org/10.3390/pr14091472 - 30 Apr 2026

Viewed by 480

Abstract

The growing global energy demand and the urgent need to decarbonize the energy sector are driving the search for renewable and low-impact energy sources. Within this context, the conversion of biomass into hydrogen represents a viable pathway to sustainable energy, enabling both carbon [...] Read more.

The growing global energy demand and the urgent need to decarbonize the energy sector are driving the search for renewable and low-impact energy sources. Within this context, the conversion of biomass into hydrogen represents a viable pathway to sustainable energy, enabling both carbon mitigation and circular use of agricultural residues. This research focuses on the simulation of an integrated system that converts viticulture residues, vine prunings and grape stalks into biogenic hydrogen through a combination of pretreatment, gasification, and upgrading stages. The analysis of four different supply scenarios shows that the integration of prunings and stalks ensures the highest hydrogen yield (6.61 × 10⁵ Nm³/year of H₂) and the highest energy self-sufficiency, with 25% of produced syngas used to partially cover internal energy demand. Gasification enables the process to be carbon-negative, saving 1.18 kgCO₂eq for Nm³ of H₂ produced, and economically competitive, with a break-even price of 3.81 €/kg and a return on investment of ten years. The study aligns with the decarbonization goals of the European energy transition, promoting local and circular valorization of agro-industrial waste. Full article

(This article belongs to the Special Issue The Recycling Process of Agro-Industrial Waste)

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