Conventional Thermal Methods Research Articles

Graphene-reinforced titanium coatings deposited by Cold Gas Spray: Study of microstructure, mechanical and wear properties

This study integrates graphene-based nanostructures as reinforcement in a Ti matrix to produce coatings using the Cold Gas Spray (CGS) technique, aiming to enhance mechanical and tribological properties while overcoming some of the limitations of conventional thermal spray methods. The hypothesis holds that incorporating Carbon Nanofibers (GFs) into Ti matrices significantly reinforces these properties compared to pure Ti coatings. The study employed ball milling for the powders obtaining, CGS deposition, and various analytical tests to evaluate the performance of Ti-GFs and pure Ti coatings. Results revealed that Ti-GFs coatings significantly improved in mechanical properties, achieving ultimate tensile strength up to 456 MPa and a strain increase to 2.27%. These improvements are attributed to effective load transfer across the Ti-GFs interfaces, facilitated by strong chemisorption interactions. Additionally, heat treatments at 1000 °C relieved residual stresses and promoted microstructural changes via atomic diffusion, further contributing to the coatings’ strength and ductility. Tribological assessments revealed a 21% reduction in the coefficient of friction for Ti-GFs coatings compared to as-sprayed Ti, though was 2% higher than that of Ti-Bulk. This suggests the potential of graphene as a nanoscale lubricant, though further optimization of GFs dispersion and interface interactions may result in even lower coefficient.These findings highlight the potential of GFs reinforced metal matrix composites applied by CGS for critical applications in sectors such as aerospace and biomedical, which demand materials with high strength and reduced mechanical wear. The study also identifies key areas for future research, including the optimization of graphene dispersion and interface bonding, to fully exploit the benefits of GFs in CGS coatings.

Thermal and Pyrolysis Research on the Super Heat‐Resistant Energetic Structure of Bis[1,2,4]triazolo[1,5‐b;5’,1’‐f][1,2,4,5]tetrazine‐2,7‐diamine

AbstractThermal stability of energetic materials determines their applicability under high temperature conditions, while few energetic materials could achieve thermal decomposition peak temperatures above 450°C. Based on a novel nitrogen‐rich fused heterocyclic skeleton, bis[1,2,4]triazolo[1,5‐b;5’,1’‐f][1,2,4,5]tetrazine‐2,7‐diamine (DATC) demonstrated super thermal stability compared to traditional heat‐resistant energetic structures. Herein, a detailed exploration was conducted on the thermal decomposition behaviors and heat‐resistant properties of DATC through conventional thermal decomposition methods combined with tandem techniques, including in‐situ FTIR and DSC/TG‐FTIR‐MS quadruple analysis. The experimental results were compared with those of 2,2’,4,4’,6,6’‐hexanitrostilbene (HNS) and 3,5‐dinitro‐N,N’‐bis(2,4,6‐trinitrophenyl)pyridine‐2,6‐diamine (PYX), two famous heat‐resistant energetic materials widely applied. The major decomposition exothermic peak temperature of DATC was found around 479°C under the heating rate of 10°C ⋅min−1 while corresponding onset decomposition temperature was around 430°C. The decomposition process of DATC was most likely initiated from the decompositions of amino groups and further destructed the molecular skeleton, which lead to a series of fragments of NH2 (m/z=16), CN (m/z=26), HCN (m/z=27), N2 (m/z=28), N2H2 (m/z=30), CN2H2 (m/z=42), HN3 (m/z=43), and C2N2 (m/z=52). Obviously, the amino groups do not contribute much to DATC's heat‐resistant performances, while the condensation of triazole moieties result in great thermal stability of the fused nitrogen‐rich skeleton. Both the decomposition process and mechanism were much different from those of HNS and PYX.

Superheated steam technology: Recent developments and applications in food industries.

Studies focused on superheated steam technology in the field of food processing have progressed rapidly over the past several decades, and this can be attributed to its remarkable heat transfer efficiency, energy-saving benefits, and environmentally friendly characteristics when compared to those of conventional thermal processing methods. Consequently, superheated steam technology holds great promise for a wider range of applications in the food industry. This study provides a comprehensive overview of the use of superheated steam technology in food processing and its impact on food quality, texture, and microbiological safety. Superheated steam is an effective thermal processing medium for tasks such as food drying, microbial decontamination, reducing the formation of toxic compounds, and enhancing the overall food quality. During superheated steam processing, the products exhibit improved flavor, color, and texture, heightened safety, and better retention of nutritional and bioactive ingredients. Additionally, the limitations and future development trends of superheated steam technology are discussed. Although the commercial adoption of superheated steam technology is still in its early stages, recent advancements suggest a promising future for its integration into the food industry.

Multiphysics Field Coupled to a Numerical Simulation Study on Heavy Oil Reservoir Development via Electromagnetic Heating in a SAGD-like Process

Conventional thermal recovery methods for heavy oil suffer from significant issues such as high water consumption, excessive greenhouse gas emissions, and substantial heat losses. In contrast, electromagnetic heating, as a waterless method for heavy oil recovery, offers numerous advantages, including high thermal energy utilization, reduced carbon emissions, and volumetric heating of the reservoir, making it a focus of recent research in heavy oil thermal recovery technologies. This paper presents a numerical simulation study of electromagnetic heating for heavy oil recovery, using a heavy oil block in the Bohai Bay oilfield in China as a case study. Firstly, a multiphysics field coupled to a mathematical model was established, considering the impact of the temperature on the heavy oil viscosity, the threshold pressure gradient of non-Darcy flow, and the dielectric properties of the reservoir, along with heat dissipation from overlying and undercover sandstone and gravitational effects on fluid flow. Secondly, a numerical simulation method for the coupled multiphysics fields was developed, and the convergence and stability of the numerical simulation method were tested. Finally, a sensitivity analysis based on the numerical simulation results identified the factors affecting heavy oil production. It was found that electromagnetic heating significantly enhances heavy oil production, and the threshold pressure gradient greatly influences the prediction of heavy oil production. Moreover, heat dissipation from the overlying and undercover sandstone severely reduces cumulative oil production. When the production well is located below the electromagnetic heating antenna, larger well spacing results in higher cumulative heavy oil production. Higher heavy oil production is achieved when the antenna is positioned at the center of the reservoir for the studied cases. Power has a big effect on increasing heavy oil production, but its influence diminishes as power increases. There exists an optimal range of electromagnetic frequencies for maximum cumulative production, and higher water saturation leads to poorer electromagnetic heating efficiency. This study provides a theoretical foundation and technical support for the numerical simulation technology and development plan optimization of heavy oil reservoirs subjected to electromagnetic heating.

Technology Progress in High-Frequency Electromagnetic In Situ Thermal Recovery of Heavy Oil and Its Prospects in Low-Carbon Situations

Heavy oil resources are abundant globally, holding immense development potential. However, conventional thermal recovery methods such as steam injection are plagued by high heat loss, substantial carbon emissions, and significant water consumption, making them incompatible with carbon reduction goals and the sustainable socioeconomic development demands. A new method of high-frequency electromagnetic in situ heating, which targets polar molecules, can convert electromagnetic energy into heat so as to achieve rapid volumetric heating of the reservoir. This method has the potential to overcome the drawbacks of traditional techniques. Nevertheless, it faces significant drawbacks such as limited heating range and inadequate energy supply during later production stages, which necessitates auxiliary enhancement measures. Various enhancement measures have been reported, including nitrogen injection, hydrocarbon solvent injection, or the use of nano-metal oxide injections. These methods are hindered by issues such as pure nitrogen being easy to breakthrough, high costs, and metal pollution. Through extensive literature review, this article charts the evolution of high-frequency electromagnetic in situ heating technology for heavy oil and the current understanding of the coupled heat and mass transfer mechanisms underlying this technology. Moreover, based on a profound analysis of the technology’s progression trends, this work introduces a new direction: CO2-N2 co-injection as an enhancement strategy for high-frequency electromagnetic in situ heavy oil recovery. There is promising potential for the development of new technologies in the future that combine high efficiency, low carbon emissions, environmental friendliness, economic viability, and energy conservation. Furthermore, some research prospects in low-carbon situations and challenges for the new technology in future are presented in detail. All in all, the contribution of the paper lies in the summarizing of some main drawbacks of current enhanced electromagnetic in situ thermal recovery methods, and presents a novel research direction of using CO2-N2 co-injection as an enhancement strategy based on its current research status in low-carbon situations.

Enhancing the Performance of Nanocrystalline SnO2 for Solar Cells through Photonic Curing Using Impedance Spectroscopy Analysis.

Wide-bandgap tin oxide (SnO2) thin-films are frequently used as an electron-transporting layers in perovskite solar cells due to their superior thermal and environmental stabilities. However, its crystallization by conventional thermal methods typically requires high temperatures and long periods of time. These post-processing conditions severely limit the choice of substrates and reduce the large-scale manufacturing capabilities. This work describes the intense-pulsed-light-induced crystallization of SnO2 thin-films using only 500 μs of exposure time. The thin-films' properties are investigated using both impedance spectroscopy and photoconductivity characteristic measurements. A Nyquist plot analysis establishes that the process parameters have a significant impact on the electronic and ionic behaviors of the SnO2 films. Most importantly, we demonstrate that light-induced crystallization yields improved topography and excellent electrical properties through enhanced charge transfer, improved interfacial morphology, and better ohmic contact compared to thermally annealed (TA) SnO2 films.

Stretchable Ag2Se Thermoelectric Fabric with Simple and Nonthermal Fabrication for Wearable Electronics

As the field of wearable electronics continues to expand, the integration of inorganic thermoelectric (TE) materials into fabrics has emerged as a promising development due to their excellent TE properties. However, conventional thermal methods for fabricating TE fabrics are unsuitable for wearable applications because of their high temperatures, resulting in rigid TE materials. Herein, a nonthermally fabricated silver selenide (Ag2Se) TE fabric is developed that can be effectively integrated into wearable applications. Ag2Se nanoparticles are densely formed within the fabric through a simple in situ chemical reduction process, resulting in remarkable electrical stability even after 10 000 cycles of mechanical deformation, such as stretching and compression. Notably, the fabricated Ag2Se TE fabric exhibits superior stretchability, stretching ≈1.36 times more than the thermally treated Ag2Se TE fabrics, while retaining its excellent electrical conductivity. Moreover, the TE unit exhibits 9.80 μW m−1 K−2 power factor, 134.45 S cm−1 electrical conductivity, and −26.98 μV K−1 Seebeck coefficient at 370 K. A haptic sensing glove based on the Ag2Se TE fabric as a sensor for detecting potential hazards is demonstrated. The glove effectively distinguishes between simple touch, physical pain, and high‐temperature hazards, ensuring user safety and prompt response.

Fine-tuning Pt nanoparticle and coordination for enhanced catalytic efficiency in microwave-assisted methylcyclohexane dehydrogenation over Pt/Al2O3 catalysts

The advancement of microwave-assisted catalysis technology will play a crucial role in the realms of energy conversion and catalysis. In this study, we developed a series of Pt/Al2O3-H catalysts by varying the reduction temperature and duration to control the Pt particle size, aiming to optimize the catalytic performance for microwave-assisted methylcyclohexane (MCH) dehydrogenation. Among the synthesized catalysts, Pt/Al2O3-H-400–15 emerged as the most effective, characterized by Pt particles of 1.5 nm and a Pt-Pt coordination number of 2.8. This particular catalyst demonstrated a high metal-support interaction, which significantly enhanced its activity and stability during the dehydrogenation process. Notably, it showed superior performance in MCH dehydrogenation under microwave irradiation, maintaining high stability and minimal methane formation over 626 h. The enhanced catalytic behavior under microwave irradiation is attributed to the elimination of low-temperature dead zones, which are commonly observed in traditional thermal catalysis, resulting in higher efficiency, greater activity, and reduced by-product and coke formation. This study underscores the potential of microwave-assisted catalysis as a more effective alternative to conventional thermal methods for the dehydrogenation of MCH.

Economical and rapid mechanochemical synthesis of porous organic adsorbents with high hydrophilicity for ultra-fast removal of organic micro-pollutants from water

Various porous adsorbent materials have shown excellent adsorption performance for the removal of organic micro-pollutants in water. However, the practical application was hindered by the high cost or slow adsorption kinetics for most of porous adsorbents. Therefore, it is of great significance to develop economic adsorbent materials with characteristic like low-cost, easier preparation method, excellent adsorption kinetics etc.Herein, based on the Friedel-Crafts alkylation reaction, we reported three novel hydrophilic organic porous adsorbent frameworks (PAF-210, PAF-211 and PAF-212) with high Brunauer-Emmet-Teller (BET) surface area (956 ∼ 1384 m2/g) for phenolic micro-pollutants (bisphenol A (BPA), 2,4-dichlorophenol (2,4-DCP) and 2-naphthol (2-NO)) adsorption in water, which were prepared by using cheap trimethyl orthoformate (TMOF) as crosslinker and one-step simple ball milling synthetic method under room temperature within 15 min. Rich oxygen content promotes the resulting polymers to possess excellent hydrophilicity and wettability through water vapor adsorption and water contact angle analysis. The excellent hydrophilicity and proper porous properties made the resulting frameworks suitable as porous organic adsorbents to rapidly remove organic phenolic micro-pollutants from water. Among the resulting polymers, the PAF-210 exhibited ultra-fast adsorption (>94.0 % within 5 s), ultra-rapid adsorption kinetics with pseudo-second-order rate constants (K2, up to 7.72g/mg min−1 for 2,4-DCP), high pollutant adsorption capacity (up to 867.03 mg g−1 for BPA) and excellent recyclability (10 cycles with slight loss in adsorption capacity) through systematically characterization. The adsorption performances of PAF-210 are much better than these of the commercial activated carbons and β-cyclodextrin-based porous adsorbents (K2 = 1.50g/mg min−1 for P-CDP) etc. The favorable hydrophilicity, surface wettability, and adsorption performance of PAF-210 were significantly better than the comparative material constructed by using benzene and formaldehyde dimethyl acetal (FDA) through conventional thermal synthetic method, which is a very classic synthesis strategy in the field of porous materials. More importantly, the PAF-210 exhibited relatively superior adsorption performance on BPA, and it still presented excellent adsorption performance (removal efficiency ≥ 96.8 % within 5 s after 10 cycles) even at the safe range of BPA quantified in drinking water (BPA≤10 μg L−1, Standards for drinking water quality, GB5749-2022, China). XPS analysis and theoretical simulations proved that the excellent adsorption performance and ultra-fast adsorption rate stem from interactions including π-π interactions, hydrogen bonding and van der Waals interactions between PAF-210 and micro-pollutants.

Pulsed electric field treatment reduces the internal stress and increases the adhesion of TiAlN coating

Higher temperatures and longer treatment times are necessary in a conventional thermal treatment method, which restricts the substrate materials and treatment efficiency. In this paper, the grain size and orientation of the coating are regulated by pulsed electric field (PEF) treatment, and the adhesion of the coating is enhanced by reducing the internal stress between the grains. The findings demonstrate that the PEF can change the coating to the close-packed (111) with high conductivity and facilitate the short-range diffusion of N atoms. The effects reduce the concentration of defects and reduce the coating’s internal stress, improving the critical load of the coating. The PEF treatment provides an effective solution for low-temperature and high-efficiency treatment coatings.

Application of radio frequency energy in processing of fruit and vegetable products.

Thermal processing is commonly employed to ensure the quality and extend the shelf-life of fruits and vegetables. Radio frequency (RF) heating has been used as a promising alternative treatment to replace conventional thermal processing methods with advantages of rapid, volumetric, and deep penetration heating characteristics. This article provides comprehensive information regarding RF heating uniformity and applications in processing of fruit and vegetable products, including disinfestation, blanching, drying, and pasteurization. The dielectric properties of fruits and vegetables and their products have also been summarized. In addition, recommendations for future research on RF heating are proposed to enhance practical applications for fruits and vegetables processing in future.

Microwave synthesized g-C3N4 nanofibers with modified properties for enhanced solar light photocatalytic performance

Graphitic carbon nitride (g-C3N4) nanomaterials have been eco-friendly synthesized using microwave and compared to the materials prepared by conventional thermal and solvothermal methods. The properties of as-synthesized g-C3N4 nanomaterials were investigated by various techniques. The results demonstrated the successful synthesis of g-C3N4 either by conventional or microwave methods. However, morphology and surface area have been changed by changing the method used. While small sheets were obtained using thermal decomposition of melamine for 4 hrs. at 500 °C, and irregular particles were obtained from the solvothermal synthesis by heating melamine and cyanuric chloride for 16 hrs. at 180 °C, nanofibers structure with the largest surface area was obtained by microwave irradiation of melamine and cyanuric chloride for 1hr. The photocatalytic performance of the synthesized materials has been assessed for the decomposition of phenol and methyl orange (MO) dye. All prepared g-C3N4 materials have shown better solar light photocatalytic performance compared to TiO2 nanoparticles. This has been directly correlated to the narrower band gab energies of g-C3N4 materials (Eg(TGCN) = 2.8 eV, Eg(SGCN) = 2.4 eV, Eg(MGCN) = 2.45 eV) compared to TiO2 (3.1 eV). Moreover, the photocatalytic activity of microwave prepared g-C3N4 (MGCN) is about 2 times higher than those prepared by the other methods (TGCN & SGCN) and ∼ 7 times higher than that of TiO2. This can be readily related to the modified fibrous structure and the highest surface area of MGCN (31.84 m2/g) compared to other materials.

Variations in quality attributes of pulsed light-treated table grape juice during refrigerated storage (4°C) and ambient conditions (25°C).

Pulsed light (PL) pasteurization is being explored as a substitute for the conventional thermal pasteurization of juices in recent times due to better retention of nutrients and overall quality. However, the long-term stability of the PL-pasteurized juice must be investigated to promote its application by the industry. The effect of PL treatment (effective fluence of 1.15 J·cm-2) and thermal treatment (90°C for 60 s) on microbial quality, enzyme activity, bioactive compounds, sensory acceptance, and color profile of table grape juice during storage at 4 and 25°C was investigated in this study. The PL pasteurization enhanced the microbial shelf-life of the juice (<6 log10cfu·mL-1) from 5 to 35 days at 4°C. The PL and thermally-pasteurized juice demonstrated a shelf-life of only 10 days when stored at 25°C. The total soluble solids and titratable acidity did not alter significantly throughout the storage period. The peroxidase, polyphenol oxidase, and pectin methylesterase activities were below 10% for the PL and thermally-treated beverage when stored at 4°C. The sensory acceptability of the PL-pasteurized juice after 35 days of refrigerated storage (6.9±0.3) was close to the untreated juice (7.2±0.3) and greater than thermally-treated juice (6.2±0.2). After the 35th day of storage at 4°C, PL-treated grape juice retained 55%, 12%, and 15.3% more phenolics, flavonoids, and antioxidant capacity, respectively, than the thermally-pasteurized juice. Hence, PL pasteurization can effectively prolong the shelf-life of table grape juice while achieving microbial and enzymatic stability, along with high sensory and nutritional appeal. PRACTICAL APPLICATION: Exploring non-thermal methods like pulsed light (PL) pasteurization as a substitute for conventional thermal methods is gaining recognition for its ability to retain nutrients and improve overall juice quality. However, the industry's adoption depends on understanding the shelf-stability of PL-pasteurized juice. This study specifically investigates the practical applications of PL treatment in comparison with conventional thermal treatment in enhancing microbial safety and enzymatic stability in table grape juice. The findings contribute insights into optimizing the shelf life of table grape juice and preserving its quality, supported by microbial, enzymatic, and sensory evaluations.

Psychrotrophic Bacteria Threatening the Safety of Animal-Derived Foods: Characteristics, Contamination, and Control Strategies.

Animal-derived foods, such as meat and dairy products, are prone to spoilage by psychrotrophic bacteria due to their high-water activity and nutritional value. These bacteria can grow at refrigerated temperatures, posing significant concerns for food safety and quality. Psychrotrophic bacteria, including Pseudomonas, Listeria, and Yersinia, not only spoil food but can also produce heat-resistant enzymes and toxins, posing health risks. This review examines the characteristics and species composition of psychrotrophic bacteria in animal-derived foods, their impact on food spoilage and safety, and contamination patterns in various products. It explores several nonthermal techniques to combat bacterial contamination as alternatives to conventional thermal methods, which can affect food quality. This review highlights the importance of developing nonthermal technologies to control psychrotrophic bacteria that threaten the cold storage of animal-derived foods. By adopting these technologies, the food industry can better ensure the safety and quality of animal-derived foods for consumers.

Thermal energy generated during ultrasonication dominates pinto bean hydration

Ultrasound-assisted hydration (UAH) stands out as a potent strategy, offering multiple advantages over conventional thermal hydration methods. It is an energy efficient, cost and time effective, easily scalable and relatively greener approach. Acoustic cavitation is the major working mechanism in aqueous phase sonication. Cavitation creates immense localised heat and pressure, which ultimately ends up heating the liquid media. To the best of our knowledge, no study dealing with the synergistic relationship between the physical effects of ultrasound and the consequent temperature rise during UAH is available in open literature. This work investigates this complex interplay with aim to identify the dominant working mechanism leading to the hydration of the pinto beans (Phaseolus vulgaris), a variety of common beans. Three different hydration protocols were devised to discern these effects, normal hydration (N) at 25 °C, temperature-controlled UAH (TC) between 18 and 20 °C using an ice bath, and temperature-uncontrolled UAH (TuC). Additionally, the post sonication residual effects of ultrasound treatment were examined. Our findings reveal that sonication induces changes in both TC and TuC treated beans, but more pronounced effects were observed in the absence of temperature control. During TC, acoustic streaming emerged as the predominant sonic action mechanism. Conversely, during TuC, temperature itself emerged as the dominant force, leading to irreversible alterations in the bean's physical and chemical structures.

Quality changes in high hydrostatic pressure treated enriched tomato sauce.

Use of high hydrostatic pressure (HHP) with reduced processing times is gaining traction in the food industry as an alternative to conventional thermal treatment. In order to enhance functional benefits while minimizing processing losses, functionalized products are being developed with such novel techniques. In this study, changes in quality parameters for HHP treated enriched tomato sauce were evaluated, with the aim to assess its viability as an alternative to conventional thermal treatment methods. HHP treatments at 500 MPa, 30 °C/50 °C significantly increased the total phenolic and lycopene content of the sauce samples, achieving 6.7% and 7.5% improvements over conventionally treated samples. The antioxidant capacity of the HHP-treated samples was also found to match or be better than conventionally treated samples. Furthermore, a T2 relaxation time study revealed that pressure-temperature processing treatments were effective in maintaining the structural integrity of water molecules. Microbiological analyses revealed that 500 MPa/50 °C 5 min treatment can offer 8 logs reduction colony formation, matching the results of conventional thermal treatment. Combined pressure-temperature treatments improve results, reduce time consumption. 500 MPa/50 °C treatments provided retention of quality parameters and significant reduction in microbial activity. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Improve the thermal performance of precooler by enhancing the utilization of chemical heat sink: Refined design method and characteristic analysis

The chemical heat sink of the coolant plays a crucial role in enhancing the performance of the precooler, which affects the overall performance of the air-breathing precooled engines. The conventional thermal design method for precoolers cannot accurately evaluate the chemical heat sink of coolants. To address this crucial issue, this paper proposes a refined model that considers the chemical reaction processes of n-Decane, based on a two-dimensional discretization unit model and the plug flow reactor model incorporating molecular-level chemical reaction mechanisms. The validation of this model is conducted by comparing it with publicly accessible data and computational fluid dynamics simulations, thereby demonstrating its excellent accuracy. Subsequently, an analysis is conducted on the factors influencing the chemical heat sink release of the coolant within the precooler, and enhanced design criteria for optimizing chemical heat sink utilization are proposed. Building upon these considerations, the performance of a precooler with a design point of Mach number 5 under off-design conditions was analyzed. The findings indicate that employing rational design methods can enhance the chemical heat sink efficiency of endothermic fuels by 8.0%, along with a concurrent 10.3% increase in the total heat sink. This underscores the significance of considering the impact of the chemical heat sink of endothermic fuels in the design of precoolers. In the case presented in this paper, the contribution of the chemical heat sink to the total heat sink within the n-Decane precooler could reach 35.3%.

Enhanced DeNOx catalysis: Induction-heating-catalysis-ready 3D stable Ni supported metal combinations

Catalysis plays a critical role in the quest for sustainable automotive technology, particularly in reducing harmful emissions from vehicles. The catalysts are required to operate efficiently in dynamic and challenging environments. This study introduces innovative deNOx catalysts featuring nominal concentrations of Pd and Re nanoparticles doped on a NiMo support. The best-performing fabricated catalyst demonstrated impressive 95 % NOx conversion at 250°C, significantly outperforming traditional systems and reducing ammonia slip. Integrating nickel as the support material was strategic choice to leverage novel induction heating-assisted catalytic system. This approach is particularly advantageous when starting cold engine, reducing harmful NOx emissions when the catalyst is not fully operational. Functional monolith model of car converter catalyst with similar composition was also developed. This research presents novel catalyst solution that achieves high deNOx efficiency while offering a cost-effective alternative to traditional methods. Induction heating enhances the catalyst's performance, particularly at lower temperatures, showcasing significant improvement over conventional thermal methods.

Energy and exergy analysis for advanced air-conditioning: Comparative evaluation of electrodialysis and aerodynamic thermal methods in liquid-desiccant reconcentration

A comprehensive exploration into the efficiency thresholds of electrodialysis (ED) and conventional aerodynamic thermal (AT) methods for reconcentrating high-concentration solutions is absent in current discourse. To address the gap, this study undertakes explicit derivations and experimental investigations to discern the divergences in energy and exergy performances between these two methods. The experimental results reveal that the ED method exhibits 6.9 times higher energy output/input ratio than the AT method, yet its exergy efficiency is 2.1 times lower in the baseline scenario due to the oversight of spent solution restoration costs. Moreover, the exergy loss of each component is identified by comparing the maximum exergy efficiency with the experimental exergy efficiency. These results help pinpoint measures to address significant exergy loss in key components, thereby boosting system performance. For the ED method, innovation and advancement in membrane technology and materials should be prioritized due to the significant limitations imposed by imperfect membranes. While for the AT method, utilizing renewable energy sources like solar energy to power the heater can greatly enhance system efficiency, considering that exergy loss within the heater is the primary limiting factor.

Exploring Innovative Applications of Evaporative Cooling for High-Total-Dissolved-Solids Produced-Water Treatment

Summary This research delves into the pioneering application of evaporative cooling (EC) to address the challenge of reducing total dissolved solids (TDS) in produced water generated during hydraulic fracturing operations in the Permian Basin. In this study, we used a meticulously designed laboratory-scale EC system comprising three cooling pads, a fan, a water reservoir, and a pump. Through a systematic series of experiments, both synthetic and authentic produced-water samples were treated, shedding light on the potential of this novel approach. The EC system efficiently processed untreated produced water, circulating it through the cooling pads, all while closely monitoring crucial variables such as inlet and outlet temperatures, relative humidity, and remaining water volume, utilizing a state-of-the-art temperature and humidity meter. Control experiments were systematically conducted to probe the influence of varying salinities, achieved by introducing NaCl into distilled water, encompassing a wide range from 0 ppm to 70,000 ppm. In addition, we extended our evaluation to real produced-water samples collected from diverse regions within the Permian Basin (Delaware, Northern Midland, and Southern Midland), reflecting the system’s capability to manage high salinity and the diverse impurities inherent to oil and gas production. A comparative analysis of energy consumption was undertaken, positioning EC against conventional thermal evaporation techniques. The findings revealed a compelling insight that differences in EC efficiency between synthetic and real oilfield brines were primarily attributed to the presence of sodium (Na+) and chlorine (Cl-) contents rather than the overall TDS concentration. Across all experiments, the system consistently achieved remarkable TDS removal efficiencies, hovering around the 100% mark for both synthetic and authentic produced-water samples. Moreover, the study unveiled a significant advantage of EC, as it proved to be significantly less energy-intensive when juxtaposed with conventional thermal evaporation methods. In addition, our experiments revealed that divalent ions like CaCl2 tend to lower the treatment efficiency compared to monovalent ions, adding a crucial dimension to our understanding of EC in water treatment. The EC system demonstrated remarkable efficiency, achieving nearly 100% TDS removal in both synthetic and real samples while being significantly less energy-intensive than conventional thermal evaporation methods. This research underscores EC’s potential as an effective, sustainable, and economical solution for high-TDS water treatment, with promising applications in industrial settings. The study also draws parallels between EC and air conditioning systems, suggesting its versatility in various industrial applications.