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Volume 13
Issue 4
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Processes, Volume 13, Issue 4 (April 2025) – 335 articles

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12 pages, 2670 KiB  
Article
Improving Thermal Environment of Power Generation Cabin via Vapor Chamber in Cold Regions
by Hao Zhai, Xianyi Jiang and Chengbin Zhang
Processes 2025, 13(4), 1260; https://doi.org/10.3390/pr13041260 - 21 Apr 2025
Abstract
This study introduces the innovative application of a vapor chamber to mitigate fuel freezing and temperature disparity in power generation cabins operating under extreme cold conditions. A vapor chamber was designed and implemented within a low-temperature power generation platform in Daqing, China, where [...] Read more.
This study introduces the innovative application of a vapor chamber to mitigate fuel freezing and temperature disparity in power generation cabins operating under extreme cold conditions. A vapor chamber was designed and implemented within a low-temperature power generation platform in Daqing, China, where outdoor temperatures were below −20 °C. The research focused on evaluating the thermal performance of the cabin under natural and forced convection conditions, with and without the vapor chamber. The experimental investigations assessed the effects of the vapor chamber on the thermal dynamics of the power generation cabin, particularly the temperature of the bottom fuel oil and the air temperature distribution. The results indicated that without the vapor chamber significant temperature disparities and potential risks to electrical equipment were present. The vapor chamber effectively utilizes the heat generated by the diesel engine, thus accelerating the heating rate of the fuel at the bottom. It reduces the duration of the decrease in the oil temperature of the upper and lower layers during the initial start-up from 0.44 h and 0.5 h to 0.31 h and 0.35 h, respectively, effectively preventing the risk of fuel freezing in the initial start-up stage. In addition, the installation of the vaporization chamber significantly improves the temperature uniformity of the air inside the cabin. The maximum temperature difference between the upper and lower air in the cabin decreases by 33 °C, effectively improving the overall thermal environment. Full article
(This article belongs to the Section Energy Systems)
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19 pages, 3436 KiB  
Article
Carbon Dioxide Capture by Alkaline Water with a Semi-Batch Column and Ultra-Fine Microbubble Generator
by Samiya A. Almamari, Salam K. Al-Dawery, Saima Farooq, Dalal H. Al Aisri, Sumaya S. Alrahbi, Aisha A. Al Fazari, Hamed N. Harharah, Ramzi H. Harharah, Salim S. Al Alawi and Gasim Hayder
Processes 2025, 13(4), 1259; https://doi.org/10.3390/pr13041259 - 21 Apr 2025
Abstract
Increased emissions of carbon dioxide (CO2) from industrial activities are the main cause of the growing problem of global warming and climate change, highlighting the needs for efficient CO2 capture and storage (CCS) techniques. The present work aims to investigate [...] Read more.
Increased emissions of carbon dioxide (CO2) from industrial activities are the main cause of the growing problem of global warming and climate change, highlighting the needs for efficient CO2 capture and storage (CCS) techniques. The present work aims to investigate the possibility of CO2 sequestration using sodium hydroxide (NaOH) in a semi-batch column with an integrated gas lift tower and an ultra-micro bubbles generator, a novel setup designed to enhance mass transfer rates and capture efficiency. Unlike the previously reported setups, our system achieves a 50% faster capture rate with improved mass transfer, enhanced gas-liquid interaction and higher removal efficiency due to finer bubble dispersion, as confirmed by experimental findings. Preliminary tests to ascertain the effectiveness of CO2 removal were carried out across various CO2 gas flow rates (3, 5, 7 L/min), NaOH volumes (2, 3, 4 L) and concentrations (0.1, 0.2, 0.3 M). The results indicated that both gas flow rate and NaOH concentration have profound impacts on the CO2 capture rate. Increasing either of these parameters, or using low concentrations of NaOH, leads to a rapid drop in pH due to a faster rate of neutralization and the formation of carbonic acid (H2CO3), a weak acidic solution. For instance, with 0.1 M NaOH and 2 L volume, the pH decreased from 13.07 to 7.02 within 1.5 min at gas flow rate of 7 L/min, while with 0.3 M NaOH, pH reduced to 7.3 after 6 min. Higher volumes and concentrations of NaOH caused a decrease in the capture rate of CO2 due to reversed reaction with formed sodium carbonate. For instance, with 0.3 M NaOH and 4 L volume, the pH reduced from 13.58 to 8 after 5 min at 7 L/min gas flow rate. Scaling up to a 100 L semi-batch column with an ultra-fine micro bubble generator, as a new approach, reduced the time taken by half in the capture of CO2. Additionally, the study also investigated the comparison of tap versus deionized water in CO2 capture reaction. The results demonstrated that dissolved minerals in tap water, particularly Ca2+ and Mg2+ ions, affected precipitate formation and capture efficiency differently than deionized water, offering practical insights for CCS in varied water sources. Full article
(This article belongs to the Special Issue Thermal and Fluid Flow Processes in Sustainable and Conventional Energy)
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13 pages, 6794 KiB  
Article
Study of Nickel–Chromium-Containing Ferroalloy Production
by Assylbek Abdirashit, Bauyrzhan Kelamanov, Otegen Sariyev, Dauren Yessengaliyev, Aigerim Abilberikova, Talgat Zhuniskaliyev, Yerbol Kuatbay, Magauiya Naurazbayev and Alibek Nazargali
Processes 2025, 13(4), 1258; https://doi.org/10.3390/pr13041258 - 21 Apr 2025
Abstract
This article presents the results of laboratory studies on the smelting of nickel–chromium-containing ferroalloys from low-grade nickel ores from Kazakhstan. X-ray phase analysis was performed on raw materials, which included quartz, nontronite, chromium metahydroxide, goethite, magnetite, iron chromite, and nickel (II) silicate. The [...] Read more.
This article presents the results of laboratory studies on the smelting of nickel–chromium-containing ferroalloys from low-grade nickel ores from Kazakhstan. X-ray phase analysis was performed on raw materials, which included quartz, nontronite, chromium metahydroxide, goethite, magnetite, iron chromite, and nickel (II) silicate. The reduction reactions of metal oxides with carbon and carbon monoxide were studied as the temperature increased. Experimental smelting was carried out in a Tammann furnace at 1500–1550 °C using three types of reducing agent: RK coke, as well as its mixtures with low-ash Shubarkol coal, in ratios of 75:25 and 50:50. The second option demonstrated the highest economic efficiency, achieving a 91% nickel recovery rate, reduced coke consumption, and a slag-to-metal ratio of 3.07. Chemical analysis showed that the nickel content in the obtained alloys ranged from 2.5% to 6.5%, while chromium content ranged from 2.6% to 4.5%. X-ray phase analysis confirmed the presence of Fe2Ni0.6Si, Fe5Si3, and Fe2CrSi phases in the alloy structure. Local element concentrations varied within the following ranges: Fe—55–59%, Ni—2–10%, Cr—2–7%, and Si—29–35%. The results of this study confirmed the feasibility of producing a nickel–chromium-containing alloy with a nickel content of 2–10% and a chromium content of 2–7%. Full article
(This article belongs to the Section Manufacturing Processes and Systems)
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16 pages, 4940 KiB  
Article
Substrate and Doping Effects on the Growth Aspects of Zinc Oxide Thin Films Developed on a GaN Substrate by the Sputtering Technique
by R. Perumal, Lakshmanan Saravanan and Jih-Hsin Liu
Processes 2025, 13(4), 1257; https://doi.org/10.3390/pr13041257 - 21 Apr 2025
Abstract
A one-micron-thick pure zinc oxide (ZnO) and nitrogen-doped zinc oxide (N-ZnO) film were fabricated on p-type, pristine (non-porous), and porous gallium nitride (GaN) substrates using a radio frequency (RF) sputtering technique at room temperature. The doping medium was nitrogen gas, which has a [...] Read more.
A one-micron-thick pure zinc oxide (ZnO) and nitrogen-doped zinc oxide (N-ZnO) film were fabricated on p-type, pristine (non-porous), and porous gallium nitride (GaN) substrates using a radio frequency (RF) sputtering technique at room temperature. The doping medium was nitrogen gas, which has a flow rate that ranges from 0 to 10 sccm (0 sccm refers to pure ZnO). The photoelectrochemical etching process, using ultraviolet light, was employed to etch the wafer surface and create a porous GaN substrate. ZnO films were developed on GaN with ZnO powder as the target material under vacuum conditions. This research aimed to investigate how variations in substrate and doping influenced the structural, optical, and electrical characteristics of the resulting thin films. The SEM images indicated that the pores developed on the etched GaN surface had a spherical shape. The A1 (LO) phonon peak at 750.2 cm−1 was observed in the Raman spectrum of the etched porous GaN. The X-ray diffraction (XRD) analysis confirmed that the films grown on GaN possessed a hexagonal wurtzite structure and the observed peak shift of (101) in all N-ZnO films suggested interstitial nitrogen doping. For the N-ZnO films, the UV-visible cut-off wavelength shifted towards the blue region. The root mean square (RMS) roughness of the N-ZnO films, measured using atomic force microscopy (AFM), was found to decrease with an increasing N-doping concentration. The 10 sccm sample exhibited the lowest roughness value of 1.1 nm, whereas the pure ZnO film showed the highest roughness of 3.4 nm. The N-ZnO thin films were found to exhibit p-type conductivity, as computed by Hall measurements using the van der Pauw method, and the higher value of carrier concentration obtained for the nitrogen gas flow rate of 8 sccm was 5.29 × 1021 cm−3. Full article
(This article belongs to the Special Issue Applications of Multifunctional Materials and Novel Engineering Techniques)
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15 pages, 4070 KiB  
Review
Sustainable Bio-Based Epoxy Technology Progress
by Chunfu Chen
Processes 2025, 13(4), 1256; https://doi.org/10.3390/pr13041256 - 21 Apr 2025
Abstract
Sustainable bio-based epoxy technology is developed by using bio-based epoxy materials instead of conventional fossil-derived ones. Significant progress in new bio-based epoxy material development on bio-based epoxy resins, curing agents, and additives, as well as bio-based epoxy formulated products, has been achieved recently [...] Read more.
Sustainable bio-based epoxy technology is developed by using bio-based epoxy materials instead of conventional fossil-derived ones. Significant progress in new bio-based epoxy material development on bio-based epoxy resins, curing agents, and additives, as well as bio-based epoxy formulated products, has been achieved recently not only in fundamental academic studies but also in industrial product development. There are mainly two types of bio-based epoxy resins: conventional epoxy resins and novel epoxy resins, depending on the epoxy resin building-block type used. Bio-based conventional epoxy resins are prepared by using the bio-based epichlorohydrin to replace conventional fossil-based epichlorohydrin. Bio-based novel epoxy resins are usually prepared from epoxidation of renewable precursors such as unsaturated vegetable oils, saccharides, tannins, cardanols, terpenes, rosins, and lignin. Typical bio-based curing agents are bio-based polyamines, polyamides, amidoamines, and cardanol-based phenalkamine-type curing agents. Cardanol is a typical bio-based reactive additive available commercially. Certain types of partially bio-based formulated epoxy products have been developed and supplied for use in bonding, coating, casting, composite, and laminating applications. Full article
(This article belongs to the Special Issue Research on Polymer Processing Technology)
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17 pages, 3400 KiB  
Article
Pipeline Inspection Gauge Trap Integrity Estimation for Upcoming Pigging Activities on Midstream Pipeline
by Marko Jarić, Sanja Petronić, Zagorka Brat, Suzana Polić and Ivana Vasović Maksimović
Processes 2025, 13(4), 1255; https://doi.org/10.3390/pr13041255 - 21 Apr 2025
Abstract
This paper focuses on a midstream pipeline to help us develop a better understanding of Pipeline Inspection Gauge (PIG) operation. A methodological combination of non-destructive testing (NDT), non-destructive evaluation (NDE), and risk-based inspection (RBI) was applied within an engineering system compatible with industry [...] Read more.
This paper focuses on a midstream pipeline to help us develop a better understanding of Pipeline Inspection Gauge (PIG) operation. A methodological combination of non-destructive testing (NDT), non-destructive evaluation (NDE), and risk-based inspection (RBI) was applied within an engineering system compatible with industry standards. In this sense, the implementation of the protocol and an assessment of the effectiveness of the proposed research model for solving problems that occur during a PIG’s working life, such as damage mechanisms and methods for its repair, are presented. The RBI methodology is derived using two mutually validating approaches to provide a result with low uncertainty. The result of this research confirms the expediency of the multi-perspective research approach and demonstrates the applicability of this methodology through a model study in the area of protocol creation—an essential aspect of ensuring the safety of pipeline inspections. Full article
(This article belongs to the Section Process Control and Monitoring)
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23 pages, 4395 KiB  
Article
Carbon Footprint Analysis of Chemical Production: A Case Study of Blue Hydrogen Production
by Eric Y. H. Chan, Zulfan Adi Putra, Raymond R. Tan, Yoke Kin Wan and Dominic C. Y. Foo
Processes 2025, 13(4), 1254; https://doi.org/10.3390/pr13041254 - 21 Apr 2025
Abstract
Interest in hydrogen has grown as a means to decarbonize future energy systems. To maximize hydrogen’s potential as the main energy carrier, the infrastructure for hydrogen production, distribution, and storage needs to be designed and developed at a global scale. Carbon footprint analysis [...] Read more.
Interest in hydrogen has grown as a means to decarbonize future energy systems. To maximize hydrogen’s potential as the main energy carrier, the infrastructure for hydrogen production, distribution, and storage needs to be designed and developed at a global scale. Carbon footprint analysis is an important metric for ensuring that the environmental impact of the developed plant is kept at a minimum. However, application of conventional methods during the conceptual design stage is challenging due to lack of detailed process data coupled with the large number of potential designs to be vetted. As a result, there is a need to develop rapid screening techniques that can be used during the conceptual design stage to gauge potential carbon footprints. To address this issue, a simplified carbon footprint analysis method is proposed in this work. Two indices are introduced, i.e., “product carbon intensity” and “economic carbon intensity”, to allow comprehensive analysis of the performance of design alternatives. By limiting the scope and basic economic analysis, the simplified carbon footprint analysis requires less data, and hence expedite the analysis process. The methodology is demonstrated through analysis of four design scenarios for blue hydrogen production. Among the scenarios, hydrogen production with both carbon capture and pre-reforming yielded better results based on product carbon intensity (2.43 kg CO2/kg H2), while design with only carbon capture performed better based on economic carbon intensity (11.25 kg CO2/USD). Thus, high potential design scenarios were successfully identified based on the newly introduced indices. Full article
(This article belongs to the Special Issue CO2 Capture and Conversion Processes: Recent Trends and Future Perspectives)
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19 pages, 4419 KiB  
Article
Development and Characterization of Environmentally Responsive Thickening Agents for Fracturing Fluids in Shale Gas Reservoir Stimulation
by Cheng Huang, Liping Mu and Xuefeng Gong
Processes 2025, 13(4), 1253; https://doi.org/10.3390/pr13041253 - 21 Apr 2025
Abstract
In response to the special requirements for shale gas reservoir stimulation, a novel environmentally responsive fracturing fluid thickener was designed and developed in this paper. N,N-dimethylhexadecylallylammonium chloride (C16DMAAC), N-vinylpyrrolidone (NVP), 2-acrylamido-2-methylpropanesulfonic acid (AMPS), and Acrylamide (AM) were used as functional monomers, and the [...] Read more.
In response to the special requirements for shale gas reservoir stimulation, a novel environmentally responsive fracturing fluid thickener was designed and developed in this paper. N,N-dimethylhexadecylallylammonium chloride (C16DMAAC), N-vinylpyrrolidone (NVP), 2-acrylamido-2-methylpropanesulfonic acid (AMPS), and Acrylamide (AM) were used as functional monomers, and the synthesis of the target product was achieved successfully through free radical polymerization in an aqueous solution. The findings indicated that in the optimized situation, where the total monomer mass fraction was 25%, the ratio of AM:AMPS:C16DMAAC:NVP was 15:10:3:2, the initiator mass fraction was 0.3%, the pH was 6.5, and the temperature was 60 °C, the thickener achieved a number-average molecular weight of 1.13 × 106. Furthermore, its remarkable thermal stability was manifested, as it only experienced a 15% mass loss in the temperature interval spanning from 40 °C to 260 °C. Performance evaluation results indicated that, at 120 °C, the viscosity of the thickener under study increased by over 49% compared to the control group. Simultaneously, in a 0.4 wt% CaCl2 environment, it retained a high viscosity of 54.75 mPa·s. This value was 46.61 mPa·s greater than that of the control group. Furthermore, under the conditions of a temperature of 170 °C, the fracturing fluid viscosity remained above 68 mPa·s. Regarding the flow performance, within the flow rate range from 110 to 150 L/min, it showed a remarkable drag reduction effect, achieving a maximum drag reduction rate of 70%. At 150 °C, the fracturing fluid exhibited superior proppant-carrying efficacy, with a settlement rate that was 26.1% lower than that of the control group. The viscosity and residue content of the gel-broken fracturing fluid exceeded the requirements of industry standards. In particular, the residue content of this fracturing fluid was 21% lower than that of the control group. The research results provide an environmentally responsive fracturing fluid thickener with excellent performance for shale gas reservoir stimulation. Full article
(This article belongs to the Special Issue Circular Economy on Production Processes and Systems Engineering)
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33 pages, 2237 KiB  
Review
Fructooligosaccharides: A Comprehensive Review on Their Microbial Source, Functional Benefits, Production Technology, and Market Prospects
by Giancarlo Souza Dias, Ana Carolina Vieira, Gabriel Baioni e Silva, Nicole Favero Simões, Thais S. Milessi, Larissa Santos Saraiva, Michelle da Cunha Abreu Xavier, Andreza Aparecida Longati, Maria Filomena Andrade Rodrigues, Sergio Fernandes, Elda Sabino da Silva, Alfredo Eduardo Maiorano, Sergio Andres Villalba Morales, Rodrigo Correa Basso and Rafael Firmani Perna
Processes 2025, 13(4), 1252; https://doi.org/10.3390/pr13041252 - 21 Apr 2025
Abstract
Fructooligosaccharides (FOSs) are carbohydrates of high nutritional value with various prebiotic properties. Optimizing their production process is of significant interest for expanding commercial-scale production. This review discusses the properties and potential applications of FOSs, addressing production challenges and providing an economic market analysis. [...] Read more.
Fructooligosaccharides (FOSs) are carbohydrates of high nutritional value with various prebiotic properties. Optimizing their production process is of significant interest for expanding commercial-scale production. This review discusses the properties and potential applications of FOSs, addressing production challenges and providing an economic market analysis. Bibliometric analysis of data concerning the functional properties, production, purification, and applications of FOSs revealed an over 87% increase in the number of worldwide publications from 2012 to 2022, rising from 88 to 165. Furthermore, contributions from ninety-three countries were identified up to 2024, with Brazil ranking first, with 326 publications. Furthermore, Aureobasidium sp. and Aspergillus sp. have shown the best results for FOS production, with reported conversion in the order of 0.66 g FOS/g sucrose. Nevertheless, the formation of by-products or co-products requiring separation from the medium remains a challenge. Activated carbon, cation exchange resins, and zeolites are highlighted as key adsorbents, with the adsorption process achieving FOS purity exceeding 90%. Furthermore, membrane technology is identified as a more efficient and promising separation method. Addressing these limitations will facilitate the further expansion of the growing global FOS market, promoting a sustainable approach and their integration with biorefineries, which can enable the development of a wider range of value-added products. Full article
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11 pages, 982 KiB  
Article
Bioaccumulation of Heavy Metals in Water and Organs of Stone moroko (Pseudoraspora parva) in Freshwater in Turkey
by Semra Küçük
Processes 2025, 13(4), 1251; https://doi.org/10.3390/pr13041251 - 21 Apr 2025
Abstract
Anthropogenic activities have been causing pollution in the environment and aquaculture activities via the contamination of heavy metals from industrial developments. As a result, this environmental pollution may cause health problems in humans. In this study, water (n = 3) and fish [...] Read more.
Anthropogenic activities have been causing pollution in the environment and aquaculture activities via the contamination of heavy metals from industrial developments. As a result, this environmental pollution may cause health problems in humans. In this study, water (n = 3) and fish (n = 10–15) samples were evaluated from Topçam Barrage to assess the heavy metal concentrations in the water and tissue samples of fish, Pseudoraspora parva (muscle, liver, kidney, spleen, gonads, and gills). All samples were measured using the ICP-OES (Inductively Coupled Plasma Optical Emission Spectrometer) in conjunction with a standard solution (As, Cd, Cr, Cu, Zn, Ni, and Pb). The bioaccumulation factor (BCF), target hazard quotient (THQ), and hazard index (HI) were calculated for human health due to fish consumption. A significant degree of heavy metals was found, which followed the order of Zn > Cu > Pb > Ni > Cd > Cr for fish tissues. Heavy metal amounts were found to be mostly higher for Cu and Pb. It was reported that their amounts were around the limit values established by the FAO (Food and Agriculture Organisation) and WHO (World Health Organisation). Further studies are needed on the precautions how to more increase the water quality level. Full article
(This article belongs to the Special Issue Research on Water Pollution Control and Remediation Technology)
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14 pages, 4119 KiB  
Article
The Development of an Alginate Drilling Fluid Treatment Agent for Shale and a Study on the Mechanism of Wellbore Stability Sealing
by Cheng Huang, Liping Mu and Xuefeng Gong
Processes 2025, 13(4), 1250; https://doi.org/10.3390/pr13041250 - 21 Apr 2025
Abstract
In order to prevent and control the problem of wellbore instability during the drilling process in shale formations, this study, based on the unique rheological properties, water solubility, and thermal stability of sodium alginate (SA), systematically investigated the rheological properties, filtration properties, and [...] Read more.
In order to prevent and control the problem of wellbore instability during the drilling process in shale formations, this study, based on the unique rheological properties, water solubility, and thermal stability of sodium alginate (SA), systematically investigated the rheological properties, filtration properties, and temperature resistance of sodium alginate-based drilling fluids before and after salt contamination. Additionally, it explored the wellbore stability and plugging mechanism of these drilling fluids in shale formations. The research shows that the BF + 0.4 wt% SA system significantly improves the rheological properties of the drilling fluid, effectively reduces the filtration loss, and exhibits good stability under the conditions of salt contamination and a high temperature of 100 °C. Sodium alginate binds to clay particles through hydrogen bonds and ionic bonds, enhancing the hydration and dispersion ability of the particles. The absolute value of its zeta potential reaches 39 mV and 37 mV before and after salt contamination, respectively, which is better than that of the control group, thus improving the colloidal stability of the drilling fluid. At the same time, through the moderate flocculation of clay particles, low-permeability filter cakes with filtration losses of 14 mL and 25 mL before and after salt contamination are formed, realizing a wellbore stability mechanism that combines physical plugging and chemical inhibition. Full article
(This article belongs to the Special Issue Circular Economy on Production Processes and Systems Engineering)
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11 pages, 7699 KiB  
Article
Mechanical and Failure Properties of Deep Grouted Fractured Rock Under Real-Time Coupling of Temperature and Dynamic Load
by Yuhao Jin, Shuo Yang, Hui Guo, Lijun Han, Lanying Huang, Shanjie Su, Pengcheng Huang, Hao Shan and Qian He
Processes 2025, 13(4), 1249; https://doi.org/10.3390/pr13041249 - 21 Apr 2025
Abstract
Deep grouting rock engineering is faced with the dual influence of high temperature and dynamic load, which has become a hot issue in geotechnical engineering. This study analyzes the mechanical responses and failure properties of deep-grouted fractured rock under real-time coupling of temperature [...] Read more.
Deep grouting rock engineering is faced with the dual influence of high temperature and dynamic load, which has become a hot issue in geotechnical engineering. This study analyzes the mechanical responses and failure properties of deep-grouted fractured rock under real-time coupling of temperature and dynamic loads through the high-temperature-split Hopkinson pressure bar (HT-SHPB), high-speed imaging, and scanning electron microscopy (SEM) tests. Key findings reveal that (1) the dynamic compressive strength of grouted fractured rock exhibits significant temperature dependency, where the strength increases with the increase of temperature, which has been verified by relevant references. From indoor temperature to 100 °C, the dynamic strength increases moderately, while a pronounced increase is observed between 100 °C and 300 °C. (2) In contrast, the dynamic peak strain demonstrates a two-stage evolution, which sharply rises from indoor temperature to 100 °C, followed by a slowly rise from 100 °C to 300 °C. (3) Macroscopically, impact fractures preferentially initiate as parallel lines at the extremities of pre-existing grouted fractures, consistent with stress concentration patterns under dynamic loading. Microscopic analysis reveals that grouting materials effectively suppress micro-crack generation and propagation at 300 °C, attributed to thermally enhanced cementation and pore-filling effects, explaining the variation of the macroscopic dynamic strength with temperature from the microscopic point of view. Full article
(This article belongs to the Special Issue Intelligent Prediction and Performance Optimization for Deep Underground Resource Excavation Process)
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22 pages, 2987 KiB  
Article
Optimal Configuration Method of Energy Routers in Active Distribution Network Considering Demand Response
by Junqing Jia, Tianyu Wu, Jia Zhou, Wenchao Cai, Zehua Wang, Junda Lu, Chen Shao and Jiaoxin Jia
Processes 2025, 13(4), 1248; https://doi.org/10.3390/pr13041248 - 20 Apr 2025
Abstract
The energy router (ER) is a crucial component in smart distribution networks, and its optimal configuration is essential for enhancing the operational efficiency, economy, and security of the grid. However, existing research rarely considers both the location and sizing costs of the ER [...] Read more.
The energy router (ER) is a crucial component in smart distribution networks, and its optimal configuration is essential for enhancing the operational efficiency, economy, and security of the grid. However, existing research rarely considers both the location and sizing costs of the ER in conjunction with flexible load demand response. Therefore, this paper proposes an optimal configuration method for the energy router in active distribution networks, incorporating demand response. First, to balance the comprehensive operational characteristics of the active distribution network throughout the year with computational efficiency, an improved K-means clustering algorithm is employed to construct multiple representative scenarios. Then, a bi-level programming model is established for ER location and sizing, considering demand response. The upper level optimizes the location and capacity configuration of the ER to minimize the overall cost of the distribution network. The lower level focuses on multi-objective optimization, including peak shaving, valley filling, network losses, and voltage deviations, to achieve energy scheduling within the distribution network. Finally, an improved bi-level particle swarm optimization algorithm is employed to solve the model. Simulation results based on the IEEE 33-node system demonstrate that the peak shaving and valley filling optimization rate after ER integration into the active distribution network is at least 9.19%, and it is improved to 14.35% when combined with demand response. Concurrently, the integration of the ER enhances the distribution network’s ability to absorb renewable energy, reduces network losses, and improves power quality. Full article
(This article belongs to the Special Issue Modeling, Optimization, and Control of Distributed Energy Systems)
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24 pages, 4367 KiB  
Article
Analysis of the Influence of Different Plasticizing Systems in a Single-Screw Extruder on the Extrusion-Cooking Process and on Selected Physical Properties of Snack Pellets Enriched with Selected Oilseed Pomace
by Jakub Soja, Maciej Combrzyński, Tomasz Oniszczuk, Marek Gancarz and Renata Różyło
Processes 2025, 13(4), 1247; https://doi.org/10.3390/pr13041247 - 20 Apr 2025
Abstract
By-products generated in the agri-food industry are frequently regarded as waste, despite their significant potential for reutilization as valuable raw materials with both nutritional and functional properties. Nigella and flaxseed pomace, as rich sources of bioactive compounds, have the capacity to enhance the [...] Read more.
By-products generated in the agri-food industry are frequently regarded as waste, despite their significant potential for reutilization as valuable raw materials with both nutritional and functional properties. Nigella and flaxseed pomace, as rich sources of bioactive compounds, have the capacity to enhance the nutritional profile and functional characteristics of extruded products while simultaneously contributing to the reduction in food waste. Uniquely, the present study analyzed the effect of extrusion-cooking process conditions on the efficiency, energy consumption, and selected physical properties of extrudates enriched with nigella and flaxseed pomace. The samples were made using a single-screw extruder-cooker. Two plasticizing (L/D 16 and 20) systems were compared. The highest efficiency, 23.16 kg/h, was reached using 20% nigella pomace with the L/D 16 system. During the whole process, the specific mechanical energy ranged from 0.006 to 0.105 kWh/kg. New information was obtained on the interaction between pomace content and the physical properties of the extrudates. The results showed that the use of 10% nigella pomace maximized the WAI 4.90 and WSI 11.73% for pellets with 30% of nigella seed pomace in the L/D 20 and influenced the change in bulk density, indicating a double innovation: an improvement in extrudate quality and the efficient use of by-products. Full article
(This article belongs to the Special Issue Feature Papers in the "Food Process Engineering" Section)
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25 pages, 1392 KiB  
Article
Dynamic Scheduling for Multi-Objective Flexible Job Shops with Machine Breakdown by Deep Reinforcement Learning
by Rui Wu, Jianxin Zheng and Xiyan Yin
Processes 2025, 13(4), 1246; https://doi.org/10.3390/pr13041246 - 20 Apr 2025
Abstract
Dynamic scheduling for flexible job shops under machine breakdown is a complex and challenging problem due to its valuable application in real-life productions. However, prior studies have struggled to perform well in changeable scenarios. To address this challenge, this paper introduces a dual-objective [...] Read more.
Dynamic scheduling for flexible job shops under machine breakdown is a complex and challenging problem due to its valuable application in real-life productions. However, prior studies have struggled to perform well in changeable scenarios. To address this challenge, this paper introduces a dual-objective deep reinforcement learning (DRL) to solve this problem. This algorithm is based on the Double Deep Q-network (DDQN) and incorporates the attention mechanism. It decouples action relationships in the action space to reduce problem dimensionality and introduces an adaptive weighting method in agent decision-making to obtain high-quality Pareto front solutions. The algorithm is evaluated on a set of benchmark instances and compared with state-of-the-art algorithms. The experimental results show that the proposed algorithm outperforms the state-of-the-art algorithms regarding machine offset and total tardiness, demonstrating more excellent stability and higher-quality solutions. At the same time, the actual use of the algorithm is verified using cases from real enterprises, and the results are still better than those of the multi-objective meta-heuristic algorithm. Full article
(This article belongs to the Special Issue Transfer Learning Methods in Equipment Reliability Management)
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17 pages, 2203 KiB  
Article
Phosphoric Acid-Assisted Enzymatic Production of Water-Soluble Cellulosic Oligomers
by Chiou-Yeong Saw, David Agus Setiawan Wibisono and Chi-Fai Chau
Processes 2025, 13(4), 1245; https://doi.org/10.3390/pr13041245 - 20 Apr 2025
Viewed by 34
Abstract
Water-soluble cellulosic oligomers (WCOs) are increasingly recognized for their prebiotic benefits, but their efficient enzymatic production is hindered by the high crystallinity of cellulose, which limits enzyme accessibility. This study introduced an efficient and scalable strategy combining phosphoric acid pretreatment with enzymatic hydrolysis [...] Read more.
Water-soluble cellulosic oligomers (WCOs) are increasingly recognized for their prebiotic benefits, but their efficient enzymatic production is hindered by the high crystallinity of cellulose, which limits enzyme accessibility. This study introduced an efficient and scalable strategy combining phosphoric acid pretreatment with enzymatic hydrolysis to produce high-purity WCOs. Microcrystalline cellulose treated with 85 wt% phosphoric acid at 10 °C exhibited significantly reduced crystallinity and crystallite size, improving its susceptibility to enzymatic degradation. Subsequent hydrolysis of the hydrated regenerated cellulose (HRC85-10) using Celluclast® at pH 7.0 for 1 h resulted in a WCO selectivity of 93.5%, with cellobiose and cellotriose identified as major oligomeric products via electrospray ionization mass spectrometry. Maintaining cellulose in a hydrated form significantly improved both the yield and selectivity of WCOs. In vivo studies further confirmed the prebiotic potential, with a significant increase in fecal Lactobacillus spp. and Bifidobacterium spp. (p < 0.05) following WCO supplementation. These findings demonstrated a practical and effective approach for producing functional WCOs for use in dietary and gut health applications. Full article
(This article belongs to the Special Issue Current Exploration of Dietary Fiber Processing and Technologies Supporting Nutrition and Health)
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16 pages, 2885 KiB  
Article
Research on the Thermodynamic Simulation Model of Antimony–Lead Synergistic Side-Blown Oxidation Smelting Process Based on MetCal
by Zhenquan Zhong, Mingzhou Li, Yuchen Feng, Baozhong Ma, Xinzhou Chen and Zhongtang Zhang
Processes 2025, 13(4), 1244; https://doi.org/10.3390/pr13041244 - 19 Apr 2025
Viewed by 103
Abstract
On the basis of the theory of polyphase equilibrium and the utilization of the MetCal software platform (MetCal v7.81), we adopted the chemical equilibrium constant method and successfully constructed a multiphase equilibrium model and simulation system for the antimony–lead synergistic side-blown oxidation smelting [...] Read more.
On the basis of the theory of polyphase equilibrium and the utilization of the MetCal software platform (MetCal v7.81), we adopted the chemical equilibrium constant method and successfully constructed a multiphase equilibrium model and simulation system for the antimony–lead synergistic side-blown oxidation smelting process. In typical production conditions, which encompass factors such as the composition of raw material, the ratio of oxygen to material, and oxygen-enriched concentration, the equilibrium product composition and pivotal technical indices are modeled and computed. Calculation results indicated that, other than the trace elements in the smelting slag, the relative errors of the calculated values for the content of major elements in the antimony-rich crude lead and smelting slag were less than 10% of the measured value after average treatment in production. Therefore, our results showed that the developed model and system preferably embodied the practical production condition of the antimony–lead synergistic side-blown oxidation smelting process, which is capable of precisely forecasting the smelting outcomes and optimizing the process parameters, thereby offering effective guidance for the practical execution of the antimony–lead synergistic side-blown oxidation smelting process. Full article
(This article belongs to the Section Chemical Processes and Systems)
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15 pages, 1085 KiB  
Review
Food Defense in the Extra Neutral Alcohol Industry: Ensuring Safety Against Intentional Contaminations
by Isabely Fernanda Pizarro, Thayná Gomes Camargo Barbosa, Marta Mitsui Kushida and Eliana Setsuko Kamimura
Processes 2025, 13(4), 1243; https://doi.org/10.3390/pr13041243 - 19 Apr 2025
Viewed by 134
Abstract
In this review article, the production of extra neutral alcohol was explored, a specific segment in the alcohol industry, aiming to fill knowledge gaps and provide information on the practical implementation of a Food Defense plan. The understanding of the physical–chemical specifications of [...] Read more.
In this review article, the production of extra neutral alcohol was explored, a specific segment in the alcohol industry, aiming to fill knowledge gaps and provide information on the practical implementation of a Food Defense plan. The understanding of the physical–chemical specifications of alcohol, its applications in food, and the manufacturing and fractionation processes were comprehensively addressed. The critical importance of extra neutral alcohol in various industries, from the production of distilled beverages to food preservation through innovative technologies, was highlighted. When discussing hazards related to food safety, the possibility of system security failures is recognized, emphasizing the need for a Food Defense plan. Additionally, we explored potential contamination methods in the production of extra neutral alcohol, analyzing its miscibility with harmful substances, which is crucial for understanding the implications of chemical contamination. The possibility of deliberate adulteration of beverages and foods requires constant attention to enhance security measures, implement advanced technologies, and proactive monitoring strategies. Ultimately, this article contributes to advancing knowledge at the intersection of extra neutral alcohol production and food safety. Full article
(This article belongs to the Special Issue Processing and Quality Control of Agro-Food Products)
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17 pages, 3105 KiB  
Article
Named Entity Recognition in Mechanical Fault Diagnosis: A Template-Free Prompt Learning Approach
by Fenfang Li, Ping Luo, Junjun Luo, Guoyu Qin and Haijun Ma
Processes 2025, 13(4), 1242; https://doi.org/10.3390/pr13041242 - 19 Apr 2025
Viewed by 118
Abstract
Intelligent prediction, accurate diagnosis, and efficient repair of mechanical equipment faults are critical for ensuring production safety and enhancing efficiency in industrial processes. However, data scarcity and recognition efficiency remain significant challenges in named entity recognition (NER) for mechanical equipment faults. To address [...] Read more.
Intelligent prediction, accurate diagnosis, and efficient repair of mechanical equipment faults are critical for ensuring production safety and enhancing efficiency in industrial processes. However, data scarcity and recognition efficiency remain significant challenges in named entity recognition (NER) for mechanical equipment faults. To address these issues, this study proposes a novel NER method based on template-free prompt learning. The model is initialized with limited labeled data and then leverages hidden entity cues in unlabeled data to generate insightful hints, guiding the model through deep retraining. Experimental results demonstrate significant improvements in F1 scores: 29.54%, 22.34%, and 19.67% on the MEFD, CONLL03, and MIT-Movie datasets, respectively, as labeled samples increased from 5 shots to 50 shots. Furthermore, compared to template-based prompt learning methods, the proposed approach achieved F1 score improvements of 9.89%, 12.97%, 9.51%, and 2.21% as labeled samples scaled from 5 shots to 50 shots. The proposed method effectively mitigates data dependency issues, enhances model generalization and application capabilities, and provides robust technical support for the intelligent identification and diagnosis of mechanical equipment faults. Full article
(This article belongs to the Section AI-Enabled Process Engineering)
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20 pages, 8177 KiB  
Article
A Position–Force Feedback Optimal Control Strategy for Improving the Passability and Wheel Grounding Performance of Active Suspension Vehicles in a Coordinated Manner
by Donghua Zhao, Mingde Gong, Yaokang Wang and Dingxuan Zhao
Processes 2025, 13(4), 1241; https://doi.org/10.3390/pr13041241 - 19 Apr 2025
Viewed by 56
Abstract
This paper aims to solve the problems of poor mobility, passability, and stability in heavy-duty vehicles, and proposes an active suspension system control strategy based on position–force feedback optimal control to coordinately enhance vehicle passability and wheel grounding performance. Firstly, a two-degrees-of-freedom one-sixth [...] Read more.
This paper aims to solve the problems of poor mobility, passability, and stability in heavy-duty vehicles, and proposes an active suspension system control strategy based on position–force feedback optimal control to coordinately enhance vehicle passability and wheel grounding performance. Firstly, a two-degrees-of-freedom one-sixth vehicle active suspension model and a valve-controlled hydraulic actuator system model are constructed, and the advantages of impedance control in robot compliance control are integrated to analyze their applicability in hydraulic active suspension. Next, a position feedback controller and force feedback LQG optimal controller for fuzzy PID control are designed, the fuzzy PID-LQG (FPL) integrated method is applied to the hydraulic active suspension system, and the dynamic load of the wheel is tracked by impedance control to obtain the spring mass displacement correction. Then, a suspension system model under the excitation of a C-class road surface and a 0.11 m raised road surface is constructed, and the dynamic simulation and comparison of active/passive suspension systems are carried out. The results show that, compared with PS and LQR control, the body vertical acceleration, suspension dynamic deflection, and wheel dynamic load root-mean-square value of the proposed FPL integrated control active suspension are reduced, which can effectively reduce the body vibration and wheel dynamic load and meet the design objectives proposed in this paper, effectively improving vehicle ride comfort, handling stability, passability, and wheel grounding performance. Full article
(This article belongs to the Section Automation Control Systems)
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22 pages, 6091 KiB  
Article
A Computational Fluid Dynamics Simulation Study on the Variation of Temperature and Pressure in the Container During the Dry Storage Process of Radioactive Metal Oxides
by Junxiang Chen, Guanchen Zhou, Dehui Wu, Peng Zhang, Fei Xie, Jiapeng Liu and Weimin Yang
Processes 2025, 13(4), 1240; https://doi.org/10.3390/pr13041240 - 19 Apr 2025
Viewed by 111
Abstract
Radioactive metal oxides are highly radioactive, hygroscopic spent fuel reprocessing products generally stored in container-sealed dry storage. During the storage process of metal oxides, a large amount of heat is generated due to radioactive decay, and helium is produced by α-decay, which leads [...] Read more.
Radioactive metal oxides are highly radioactive, hygroscopic spent fuel reprocessing products generally stored in container-sealed dry storage. During the storage process of metal oxides, a large amount of heat is generated due to radioactive decay, and helium is produced by α-decay, which leads to an increase in the temperature and pressure of the storage container. In order to ensure the safety of the radioactive metal oxides in the long-term storage process, computational fluid dynamics simulations are used to investigate the effects of storage conditions on the temperature and pressure of the container. Based on a large amount of simulated temperature data under different storage conditions, a power function is used to construct a mathematical model of ventilation speed, ventilation temperature, stack density, loading volume, heating power, water content, and cumulative helium mass versus metal oxide temperature to obtain a safe, reliable, and economical storage method. The results show that reducing the loading volume and increasing the density of metal oxides, increasing the ventilation speed, and lowering the ventilation temperature are beneficial to the heat transfer and cooling in the dry storage process; increasing the density of metal oxides and lowering the water content of metal oxides and increasing the ventilation temperature and speed are beneficial to avoid the high pressure inside the container. Based on the optimized storage conditions, the temperature peak in the storage process occurs near 25 years, and its temperature reaches 527.6 K. The mathematical model of storage temperature constructed in this study has high computational accuracy, and the maximum relative error of storage temperature is less than 1.80%. Full article
(This article belongs to the Section Energy Systems)
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18 pages, 7880 KiB  
Article
Bearing Fault Diagnosis Based on Multiscale Lightweight Convolutional Neural Network
by Yunhao Cui, Zhihui Zhang, Zhidan Zhong, Jian Hou, Zhiyong Chen, Zhicheng Cai and Jun-Hyun Kim
Processes 2025, 13(4), 1239; https://doi.org/10.3390/pr13041239 - 19 Apr 2025
Viewed by 63
Abstract
Many bearing fault diagnosis methods often struggle to balance between adequate feature extraction and lightweight property, which makes it somewhat difficult to fulfill the accuracy and efficiency required for practical applications. To address this issue, this study describes the development of a multiscale [...] Read more.
Many bearing fault diagnosis methods often struggle to balance between adequate feature extraction and lightweight property, which makes it somewhat difficult to fulfill the accuracy and efficiency required for practical applications. To address this issue, this study describes the development of a multiscale lightweight deep learning model for accurate bearing fault diagnosis. Specifically, the Gaussian pyramid method, which can create a series of images at different scales, is employed to express the Gramian angular field (GAF) matrix images generated by transforming the bearing vibration signals to avoid the common problem of insufficient feature extraction of a single-scale image. At the same time, the dependencies between feature channels are extracted using a lightweight attention mechanism utilized in deep learning, known as Efficient Channel Attention (ECA), to improve the capability of feature representation. This approach effectively improves the learning ability of bearing fault characteristics and greatly increases the accuracy of fault diagnosis. Considering the problem related to the lightweight level of the method, a Ghost module, a type of convolution neural network system, is also employed to generate more features by using fewer parameters, thereby improving the overall calculation efficiency. Here we have developed a residual module based on the Ghost module and ECA, which can be easily integrated into most bearing fault diagnosis backbone networks. Based on our experimental tests, the developed system can clearly achieve high accuracy precision of bearing fault diagnosis to fulfill the needs of practical engineering while maintaining light weight. Specifically, the test accuracy of the proposed method using two bearing fault datasets exceeds 99.4%, and the giga floating-point operations (GFLOPs) is only 1.99, which can fully meet the needs of practical engineering. Full article
(This article belongs to the Special Issue Process Automation and Smart Manufacturing in Industry 4.0/5.0)
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20 pages, 13904 KiB  
Article
Numerical Simulation of the Interfacial Dynamics of Highly Viscous Fluid on a Single Packing Element by the Volume-of-Fluid Method
by Xin Liu, Junhao Wang and Zhengming Gao
Processes 2025, 13(4), 1238; https://doi.org/10.3390/pr13041238 - 19 Apr 2025
Viewed by 110
Abstract
The dynamic characteristics of liquid with high viscosity impact on stagnant packing are investigated by a computational fluid dynamics (CFD) method. The three-dimensional model, employing the volume-of-fluid (VOF) approach, simulates the evolution of liquid profiles and describes four interaction stages—approaching, encapsulation, uncovering, and [...] Read more.
The dynamic characteristics of liquid with high viscosity impact on stagnant packing are investigated by a computational fluid dynamics (CFD) method. The three-dimensional model, employing the volume-of-fluid (VOF) approach, simulates the evolution of liquid profiles and describes four interaction stages—approaching, encapsulation, uncovering, and detachment—between the liquid and the packings, including Raschig rings, Pall rings, and Cascade mini rings. Based on the analysis of liquid dynamic behavior, the effects of packing type, packing size, and liquid viscosity on the liquid holding volume, film area, and surface renewal rate of highly viscous fluid in packing are analyzed. Furthermore, a correlation is developed to predict the specific area of liquid in terms of dimensionless numbers. This work provides a fundamental reference for realizing the interfacial characteristics in packed columns involving highly viscous fluids. Full article
(This article belongs to the Special Issue Applications of Computational Fluid Dynamics (CFD) in Chemical Process Simulations)
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13 pages, 2013 KiB  
Article
Improving Stability of Biodiesel from 20% Free Fatty Acid Palm Oil with Tert-butylhydroquinone at Various Concentrations for 52 Weeks of Storage
by Tunyaboon Laemthong, Sarun Triwittayayont, Netipon Sakulshah, Chanin Khomlaem, Nutchapon Chiarasumran, Anusith Thanapimmetha, Maythee Saisriyoot, Wei-Cheng Wang, Ya-Yu Chiang and Penjit Srinophakun
Processes 2025, 13(4), 1237; https://doi.org/10.3390/pr13041237 - 19 Apr 2025
Viewed by 245
Abstract
Overcoming the oxidation stability of biodiesel has been a significant challenge, especially after an extended storage period. To test a major factor affecting biodiesel quality, eight different conditions consisting of water at a concentration of 500 ppm and tert-butylhydroquinone (TBHQ) concentrations of 500, [...] Read more.
Overcoming the oxidation stability of biodiesel has been a significant challenge, especially after an extended storage period. To test a major factor affecting biodiesel quality, eight different conditions consisting of water at a concentration of 500 ppm and tert-butylhydroquinone (TBHQ) concentrations of 500, 1000, and 2000 ppm, in combination, were added to palm biodiesel, with no-water-added treatment as the control. Samples were kept in dark storage and air-limited at room temperature for 52 weeks with an initial carbon residue of 0.05 wt%. Every sample was periodically taken for property examination, which included the percentage of fatty acid methyl ester (FAME), iodine value (IV), kinematic viscosity (KV), acid value (AV), and oxidation stability. The properties of the samples with 500 ppm of water-added biodiesel exhibited the most significant degradation, even though oxidation stability (starting from 43.37 h) remained higher than 10.00 h after 32 weeks. The IV dropped 48.43% from 49.92 to 25.56 g I2/100 g. The KV increased 6.14% from 4.56 to 4.84 cSt. The AV rose from 0.45 to 1.09 mg KOH/g. Biodiesel with 2000 ppm TBHQ added was stable for 22 weeks, with all properties under standard values. However, biodiesel in the same condition but with water contamination, its stability was reduced to 16 weeks. Full article
(This article belongs to the Special Issue Trends in Biochemical Processing Techniques)
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15 pages, 6246 KiB  
Article
Research and Application of Gas Drainage Negative Pressure Regulation Method Considering Permeability Differences
by Xiaoyu Cheng, Cheng Cheng, Hui Wang, Lu Xiao and Xingying Ma
Processes 2025, 13(4), 1236; https://doi.org/10.3390/pr13041236 - 19 Apr 2025
Viewed by 158
Abstract
This study investigates a dynamic regulation strategy for intelligent gas drainage negative pressure using a comprehensive approach involving numerical simulations, intelligent algorithms, and field experiments. In the numerical simulation component, a permeability evolution model was developed to characterize the area in front of [...] Read more.
This study investigates a dynamic regulation strategy for intelligent gas drainage negative pressure using a comprehensive approach involving numerical simulations, intelligent algorithms, and field experiments. In the numerical simulation component, a permeability evolution model was developed to characterize the area in front of the mining face. Simulations were performed under three negative pressure settings (13 kPa, 18 kPa, and 25 kPa) to investigate the relationships among drainage negative pressure, gas concentration, and flow rate. For the intelligent algorithm, a Long Short-Term Memory (LSTM) prediction model was developed to forecast drainage negative pressure. Based on the predictions, a dynamic regulation strategy for intelligent gas drainage negative pressure was formulated. For field validation, a 120-day in situ experiment was carried out. Intelligent control valves and monitoring instruments were deployed across various sections of the coal seam ahead of the mining face, validating the proposed regulation strategy. The results indicate that permeability is highest in the pressure-relief zone ahead of the mining face and lowest in the stress concentration zone. In the original stress zone, which is unaffected by mining disturbances, the permeability remains unchanged. Drainage negative pressure is positively correlated with gas flow rate, but negatively correlated with gas concentration. In the stress concentration zone, when drainage negative pressure reaches 25 kPa, permeability ceases to be the dominant factor influencing gas flow. At this stage, the pressure gradient between the gas in coal fractures and the drainage system becomes the primary driving force for gas flow. The intelligent dynamic regulation strategy for gas drainage, underpinned by the LSTM prediction model, demonstrated strong performance in field applications. Following intelligent regulation, gas concentrations in various regions showed significant improvement. The findings of this study actively contribute to the advancement of intelligent gas drainage technology. Full article
(This article belongs to the Special Issue Advances in Coal Processing, Utilization, and Process Safety)
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13 pages, 1555 KiB  
Article
Enhancing Heavy Metal Removal and Stabilization in River Sediment by Combined Application of Nanoscale Zero-Valent Iron and Sediment Microbial Fuel Cells
by Xun Xu, Mingsong Wu and Guoling Ren
Processes 2025, 13(4), 1235; https://doi.org/10.3390/pr13041235 - 18 Apr 2025
Viewed by 111
Abstract
This study investigates the effect of nanoscale zero-valent iron (NZVI) and sediment microbial fuel cells (SMFCs) on the three typical heavy metals’ (Pb, Cr and As) removal and stabilization. Results showed that the combined use of NZVI and SMFCs obtained the highest removal [...] Read more.
This study investigates the effect of nanoscale zero-valent iron (NZVI) and sediment microbial fuel cells (SMFCs) on the three typical heavy metals’ (Pb, Cr and As) removal and stabilization. Results showed that the combined use of NZVI and SMFCs obtained the highest removal efficiencies in the sediment (Pb 37.7 ± 2.2%, Cr 26.4 ± 1.5% and As 30.1 ± 2.0%) and overlying water (Pb 55.8 ± 2.3%, Cr 47.6 ± 1.9% and As 45.8 ± 2.1%). The use of an NZVI electrode can transform heavy metals with relatively weak binding into forms with stronger binding, thereby diminishing their bioavailability and toxicity. After 60 days of operation with the addition of NZVI in the SMFC system, over 50% of the Pb, Cr and As in the sediment was transformed into the residual fraction. An anodic microbial communities analysis indicated that operating a SMFC can mitigate the adverse effects of NZVI on the community diversity and increase the content of electrogenic bacteria in sediments. Consequently, our findings indicated that integrating SMFCs and NZVI represents a viable approach for remediating rivers contaminated with heavy-metal-polluted sediments. Full article
(This article belongs to the Section Environmental and Green Processes)
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18 pages, 1713 KiB  
Article
Development of Oil-Free Lubricants for Cold Rolling of Low-Carbon Steel
by Leon Jacobs, Delphine Rèche, Andreas Bán, Valentina Colla, Orlando Toscanelli, Martin Raulf, Martin Schlupp, Bas Smeulders, Mike Cook and Wim Filemon
Processes 2025, 13(4), 1234; https://doi.org/10.3390/pr13041234 - 18 Apr 2025
Viewed by 111
Abstract
Oil-in-water emulsions (O/W emulsions) are generally used to lubricate the cold rolling process of low-carbon steel. In addition to the obvious advantages of efficient lubrication and cooling of the process, there are also some disadvantages, mainly related to emulsion bath maintenance, subsequent production [...] Read more.
Oil-in-water emulsions (O/W emulsions) are generally used to lubricate the cold rolling process of low-carbon steel. In addition to the obvious advantages of efficient lubrication and cooling of the process, there are also some disadvantages, mainly related to emulsion bath maintenance, subsequent production steps and waste disposal. In some application areas, Oil-Free Lubricants (OFL’s) have been shown to be at least equally effective in decreasing friction and wear as conventional oil-based lubricants, while resulting in benefits related to waste disposal. In 2023, a project named “Transfer of aqueous oil free lubricants into steel cold rolling practice” (acronym ‘RollOilFreeII’) began, with it receiving funding from the Research Fund for Coal and Steel (RFCS). This project aims at an industrial application of Oil-Free Lubricants in the steel cold rolling process. The project builds on the work of the ‘RollOilFree’ project (also carried out in the RFCS-framework). This article briefly recapitulates the findings in the RollOilFree project and describes the objectives, benefits, activities and first results of the RollOilFreeII project. Notably, a pilot mill trial at high speed has been carried out, showing a good performance of the investigated OFLs. Back-calculated friction values were equal to, or even slightly lower than, reference O/W emulsions. The strip cleanliness with OFLs is much better than it is with the reference O/W emulsions. Only for a very thin product, as is the case in tinplate rolling, does the direct application of a conventional O/W dispersion (a high-particle-sized O/W emulsion) give a better performance than the investigated OFLs. Further development of OFLs should focus on this aspect. Full article
(This article belongs to the Special Issue Recent Advances in Surface Engineering and Coating Technologies in Manufacturing Processes)
21 pages, 1127 KiB  
Article
Design and Adaptability Analysis of Integrated Pressurization–Gas Lifting Multifunctional Compressor for Enhanced Shale Gas Production Flexibility
by Kunyi Wu, Lin Qu, Jun Zhou, Yan He, Yu Wu, Zonghang Zhou, Can Qin, Longyu Chen and Chenqian Zhang
Processes 2025, 13(4), 1233; https://doi.org/10.3390/pr13041233 - 18 Apr 2025
Viewed by 105
Abstract
Shale gas development has made significant contributions to the increase in natural gas production capacity in recent years, particularly in promoting the transformation of the energy structure and enhancing energy autonomy. However, with the deepening of shale gas field exploitation, particularly in the [...] Read more.
Shale gas development has made significant contributions to the increase in natural gas production capacity in recent years, particularly in promoting the transformation of the energy structure and enhancing energy autonomy. However, with the deepening of shale gas field exploitation, particularly in the later stages of development, low-pressure gas wells and liquid accumulation issues have become increasingly apparent, posing significant challenges to the normal production of gas wells. Traditional single gas lifting and pressurization techniques have disadvantages such as high equipment investment, high operating costs, and inflexibility in switching, which make it difficult to meet the long-term and stable production needs of shale gas fields. Therefore, to overcome these challenges, this study proposes an innovative integrated pressurization–gas lifting multifunctional compressor process, which achieves the “pressurization ↔ gas lifting ↔ pressurization–gas lifting synergy” multi-mode intelligent switching function through modular integration design, resulting in higher production flexibility and efficiency. Adaptability assessments were completed on two typical shale gas platforms, and field test results show that the equipment can achieve stable production increases across all three functional modes. The pressurization mode demonstrates good adaptability in gas processing, efficiently pressurizing and transporting natural gas produced from the platform’s wells, meeting the increasing demand for gas export. The gas lifting function of the equipment can effectively address gas wells affected by wellbore or bottom-hole liquid accumulation, improving production conditions. In the synergy mode, the equipment design enables the effective collaboration of pressurization and gas lifting functions. Driven by the same power source, the two functional modules work efficiently together, adapting to complex production conditions where both gas lifting and pressurization for gas export occur simultaneously. The innovative process paradigm developed by this study provides an engineering solution for the entire lifecycle of shale gas field development, characterized by equipment integration and intelligent operation, offering significant economic benefits and promotional value. Full article
(This article belongs to the Special Issue 2nd Edition of Artificial Intelligent Techniques in the Optimal Operation of Oil and Gas Production Systems)
19 pages, 3480 KiB  
Article
Theory-Driven Multi-Output Prognostics for Complex Systems Using Sparse Bayesian Learning
by Jing Yang, Gangjin Huang, Hao Liu, Yunhe Ke, Yuwei Lin and Chengfeng Yuan
Processes 2025, 13(4), 1232; https://doi.org/10.3390/pr13041232 - 18 Apr 2025
Viewed by 77
Abstract
Complex systems often face significant challenges in both efficiency and performance when making long-term degradation predictions. To address these issues, this paper proposes a predictive architecture based on multi-output sparse probabilistic model regression. An adaptive health index (HI) extraction method was also introduced, [...] Read more.
Complex systems often face significant challenges in both efficiency and performance when making long-term degradation predictions. To address these issues, this paper proposes a predictive architecture based on multi-output sparse probabilistic model regression. An adaptive health index (HI) extraction method was also introduced, which leverages unsupervised deep learning and variational mode decomposition to effectively extract health indicators from multiple measurements of complex systems. The effectiveness of the proposed method was validated using both the C-MAPSS and FLEA datasets. The case study results demonstrate that the proposed prognostic method delivered an outstanding performance. Specifically, the feature extraction method effectively reduced the measurement noise and produced robust HIs, while the multi-output sparse probabilistic model achieved lower prediction errors and a higher accuracy. Compared to traditional single-step forward-prediction methods, the proposed approach significantly reduced the time required for long-term predictions in complex systems, thus improving support for online status monitoring. Full article
(This article belongs to the Special Issue Applications of Artificial Intelligence Technologies in Energy, Manufacturing and Automatic Control Processes)
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13 pages, 1244 KiB  
Article
Optimizing Hydrogen Production Through Efficient Organic Matter Oxidation Performed by Microbial Electrolysis Cells
by Angela Marchetti, Miriam Cerrillo Moreno, Roberto Lauri and Marco Zeppilli
Processes 2025, 13(4), 1231; https://doi.org/10.3390/pr13041231 - 18 Apr 2025
Viewed by 127
Abstract
Microbial electrolysis cells (MECs) represent a pioneering technology for sustainable hydrogen production by leveraging bioelectrochemical processes. This study investigates the performance of a single-chamber cathodic MEC, where a cation exchange membrane separates the electrically active bioanode from the cathode. The system was constantly [...] Read more.
Microbial electrolysis cells (MECs) represent a pioneering technology for sustainable hydrogen production by leveraging bioelectrochemical processes. This study investigates the performance of a single-chamber cathodic MEC, where a cation exchange membrane separates the electrically active bioanode from the cathode. The system was constantly fed with a synthetic carbonaceous solution, employing a working potential of +0.3 V vs. SHE and an organic loading rate of 2 gCOD/Ld with a hydraulic retention time of 0.3 d. Notably, no methanogenic activity was detected, likely due to the establishment of an alkaline pH in the cathodic chamber. Under these conditions, the system exhibited good performance, achieving a current density of approximately 115 A/m3 and a hydrogen production rate of 1.28 m3/m3d. The corresponding energy consumption for hydrogen production resulted in 6.32 kWh/Nm3 H2, resulting in a slightly higher energetic cost compared to conventional electrolysis; moreover, an average energy efficiency of 85% was reached during the steady-state condition. These results demonstrate the potential of MECs as an effective and sustainable approach for biohydrogen production by helping the development of greener energy solutions. Full article
(This article belongs to the Special Issue Sustainable Hydrogen Production Processes)
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