Large-scale Industrial Applications Research Articles

Automatic detection of surface defects based on deep random chains

Defect detection is critical in production systems. The traditional methods are primarily manual, prohibiting its large-scale industrial application. The current deep learning methods usually require a large amount of data, which is challenging in some cases. This paper presents a novel deep learning method to detect a large variety of defects based on small datasets only. Specifically, the method is based on the deep random chain combined with the adaptive Faster R-CNN. The idea behind this method is to fuse both common and different types of information among candidate groups to each defect candidate, which thus improves the model’s generalization for small sample datasets with a wide variety of defects. Indeed, the deep random chains focus on learning the relationship among the pixels inside each defect, while many features are added to each defect using Faster R-CNN. Several experiments on industrial products demonstrate the merit of the proposed method for small sample datasets with yet a wide variety of defects.

Cellulose-based polypropoxy ether carboxylates as highly compatible, effective, and migration-resistant plasticizers for poly (lactic acid)

The utilization of cellulose for enhancing the strength, the PLA has received significant attention, however, poor interfacial compatibility of solid cellulose with PLA matrix still hinders their broader application. Herein, highly compatible cellulose-based polypropoxy ether carboxylates (CPPEC) were firstly manufactured via propoxylation of cellulose and following esterification with acetic acid, butyric acid, as well as oleic acid, respectively. Liquid CPPEC delivered excellent performances to PLA, especially, the values of elongation at break and low-temperature resistance of PLA blended with cellulose-based polypropoxy ether acetate (PLA/CPPEA) were respectively increased by 630.9 % and 146.3 % compared with those of neat PLA due to the synergistic effect of propyl and methyl groups in CPPEC with PLA matrix. Additionally, migration resistance of PLA/CPPEA increased 14.3 and 11.2 times, respectively, compared with those of PLA specimens blended with epoxidized soybean oil and dioctyl phthalate. All findings suggest that the CPPEC is suitable for large-scale application in the PLA industry.

Heterogeneous Federated Learning: State-of-the-art and Research Challenges

Federated learning (FL) has drawn increasing attention owing to its potential use in large-scale industrial applications. Existing FL works mainly focus on model homogeneous settings. However, practical FL typically faces the heterogeneity of data distributions, model architectures, network environments, and hardware devices among participant clients. Heterogeneous Federated Learning (HFL) is much more challenging, and corresponding solutions are diverse and complex. Therefore, a systematic survey on this topic about the research challenges and state-of-the-art is essential. In this survey, we firstly summarize the various research challenges in HFL from five aspects: statistical heterogeneity, model heterogeneity, communication heterogeneity, device heterogeneity, and additional challenges. In addition, recent advances in HFL are reviewed and a new taxonomy of existing HFL methods is proposed with an in-depth analysis of their pros and cons. We classify existing methods from three different levels according to the HFL procedure: data-level, model-level, and server-level. Finally, several critical and promising future research directions in HFL are discussed, which may facilitate further developments in this field. A periodically updated collection on HFL is available at https://github.com/marswhu/HFL_Survey.

Advancements in Doping Strategies for Enhanced Photocatalysts and Adsorbents in Environmental Remediation

Environmental pollution poses a pressing global challenge, demanding innovative solutions for effective pollutant removal. Photocatalysts, particularly titanium dioxide (TiO2), are renowned for their catalytic prowess; however, they often require ultraviolet light for activation. Researchers had turned to doping with metals and non-metals to extend their utility into the visible spectrum. While this approach shows promise, it also presents challenges such as material stability and dopant leaching. Co-doping, involving both metals and non-metals, has emerged as a viable strategy to mitigate these limitations. Inthe fieldof adsorbents, carbon-based materials doped with nitrogen are gaining attention for their improved adsorption capabilities and CO2/N2 selectivity. Nitrogen doping enhances surface area and fosters interactions between acidic CO2 molecules and basic nitrogen functionalities. The optimal combination of an ultramicroporous surface area and specific nitrogen functional groups is key to achievehigh CO2 uptake values and selectivity. The integration of photocatalysis and adsorption processes in doped materials has shown synergistic pollutant removal efficiency. Various synthesis methods, including sol–gel, co-precipitation, and hydrothermal approaches had been employed to create hybrid units of doped photocatalysts and adsorbents. While progress has been made in enhancing the performance of doped materials at the laboratory scale, challenges persist in transitioning these technologies to large-scale industrial applications. Rigorous studies are needed to investigate the impact of doping on material structure and stability, optimize process parameters, and assess performance in real-world industrial reactors. These advancements are promising foraddressing environmental pollution challenges, promoting sustainability, and paving the way for a cleaner and healthier future. This manuscript provides a comprehensive overview of recent developments in doping strategies for photocatalysts and adsorbents, offering insights into the potential of these materials to revolutionize environmental remediation technologies.

Novel bipolar membrane electrolyzer for CO2 reduction to CO in organic electrolyte with Cl2 and NaOH produced as byproducts

Electrochemical reduction of CO2 to valuable products, powered by renewable energy, provides a promising strategy for reducing our dependence on fossil fuels. But up to now, no technology has been implemented for large-scale industrial applications. Without massive utilization of CO2, many vital practical problems, such as reducing CO2 emissions, storing renewable energy, and alleviating environmental pollution, cannot be resolved through this route. Herein, we propose a novel electrolyzer for CO2 electro-reduction, which is separated into three chambers by a bipolar membrane and a cation exchange membrane. In the cathodic chamber, CO2 is reduced to CO in organic electrolytes. In the anodic chamber, Cl- is oxidized to Cl2 in NaCl aqueous solution. In the central chamber, NaOH is obtained. The generated CO and Cl2 can be used as feedstock to produce phosgene (CO+Cl2 =COCl2). Through this route, phosgene can be produced from CO2 and NaCl, with NaOH generated as a byproduct. By substantially increasing the product value, we can promote CO2 electro-reduction technology to industrial applications.

Solid-state mechanochemical synthesis of chitosan from mud crab (Scylla serrata) chitin

This study presents a method for solvent-free mechanochemical synthesis of chitosan from chitin, sourced from the shells of mud crabs (Scylla serrata). The procedure involves a sequence of demineralization and deproteinization to extract chitin from the crab shells, followed by mechanochemical deacetylation. The chitin was deacetylated by grinding it as a solid blend with sodium hydroxide (NaOH) using a stainless steel mortar and pestle. After grinding, chitosan is isolated from the blend by repetitive washing and centrifugation. The chitosan product is then characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction analysis. These characterization techniques confirm the successful deacetylation of chitin to form chitosan. A high degree of deacetylation (DD) is achieved when the weight ratio of NaOH to chitin is 1:1 or higher, implying that the DD value can be enhanced by increasing this weight ratio. The mechanochemical reaction mechanism involves the hydroxyl groups on the NaOH particles reacting with the acetamide groups of the chitin strands, yielding solid chitosan and sodium acetate. This mechanochemical deacetylation approach is more practical than the conventional heterogeneous deacetylation in strong basic solutions, since it could suppress depolymerization of the resulting chitosan and requires significantly less base. This makes it a promising method for large-scale industrial applications.

Oxygen-vacancy-type Mars–van Krevelen mechanism drives ultrafast dioxygen electroreduction to hydrogen peroxide

The electrochemical oxygen reduction reaction (ORR) along a two-electron transfer pathway has been considered as an eco-friendly route for producing hydrogen peroxide (H2O2). However, large-scale industrial application of this ORR technology calls for ultrafast and effective generation of H2O2 under operating conditions (current densities >1 A/cm2 and Faradaic efficiency ≈ 100%). This imposes strict criteria for exploring innovative strategies for enhancing the adsorption and activation of O2 under vigorous reaction condition, which represents a significant challenge thus far. Here, we report an ‘oxygen-vacancy-type’ Mars–van Krevelen mechanism for promoting ORR. Our theoretical calculations show that the structural oxygen vacancies of zinc oxide catalysts effectively alter the electron densities of nearby metal active sites, producing a more electron-deficient Zn center, which, in turn, assists the adsorption and activation of O2. A catalyst electrode designed as that exhibits superior ORR activities with a Faradaic efficiency of 98.1% at a current density of 1 A/cm2 (H2O2 yield rate of 621.88 mg/h/cm2). Further mechanism study has been performed through in situ Raman spectroscopy to monitor the adsorption and activation of oxygen intermediate (∗O2) of ORR, providing additional experimental evidence for the Mars–van Krevelen mechanism.

ACS journal reports on test of four PET-degrading enzymes

On October 12, 2023, Carbios, a developer of biological technologies to reinvent the life cycle of plastics and textiles, announced the publication scientific journal ACS Catalysis (Impact Factor 13.7), of an article entitled “Assessment of Four Engineered PET Degrading Enzymes Considering Large-Scale Industrial Applications.”

A Novel Demulsifier with Strong Hydrogen Bonding for Effective Breaking of Water-in-Heavy Oil Emulsions.

In the heavy petroleum industry, the development of efficient demulsifiers for the effective breaking of interfacially active asphaltenes (IAA)-stabilized water-in-heavy oil (W/HO) emulsions is a highly attractive but challenging goal. Herein, a novel nitrogen and oxygen containing demulsifier (JXGZ) with strong hydrogen bonding has been successfully synthesized through combining esterification, polymerization and amidation. Bottle tests indicated that JXGZ is effectual in quickly demulsifying the IAA-stabilized W/HO emulsions; complete dehydration (100%) to the emulsions could be achieved in 4 min at 55 °C using 400 ppm of JXGZ. In addition, the effects of demulsifier concentration, temperature and time on the demulsification performance of JXGZ are systematically analyzed. Demulsification mechanisms reveal that the excellent demulsification performance of JXGZ is attributed to the strong hydrogen bonding between JXGZ and water molecules (dual swords synergistic effect under hydrogen bond reconstruction). The interaction of the "dual swords synergistic effect" generated by two types of hydrogen bonds can quickly break the non-covalent interaction force (π-π stacking, Van der Waals force, hydrogen bonds) of IAA at the heavy oil-water interface, quickly promote the aggregation and coalescence of water molecules and finally achieve the demulsification of W/HO emulsions. These findings indicate that the JXGZ demulsifier shows engineering application prospects in the demulsification of heavy oil-water emulsions, and this work provides the key information for developing more efficient chemical demulsifiers suitable for large-scale industrial applications.

An integrated chemical approach for the removal of hazardous Cr(VI) and other contaminants of tannery wastewater: Biopolymer-assisted adsorption separation and conversion into valuable materials

To counter the toxic effects of Cr(VI) ions in industrial wastewater, adsorption onto a suitable adsorbent is prudent, but the resulting secondary waste accumulation and cleaning are challenging. Herein, biocompatible alginic acid has demonstrated selective adsorption of Cr(VI) ions with the subsequent conversion of the secondary waste into valuable materials. The maximum sorption was found to be 143 mg/g, and the adsorption follows the Langmuir model and pseudo-second-order kinetics. The process was tested with a simulated tannery effluent where selective Cr(VI) adsorption was achieved, and the secondary waste was converted to Cr2O3 and ZnCrO4. The remaining ions present Na+, Cl+, SO42- have been consolidated into an apatite mineral with the molecular formula of Ca4.1Na0.9(P0.7S0.3O4)3Cl. Overall, our integrated process of removing and converting Cr(VI) ions into beneficial by-products opens up a window of opportunities for large-scale water purification and industrial applications.

Assessment of Four Engineered PET Degrading Enzymes Considering Large-Scale Industrial Applications.

In recent years, enzymatic recycling of the widely used polyester polyethylene terephthalate (PET) has become a complementary solution to current thermomechanical recycling for colored, opaque, and mixed PET. A large set of promising hydrolases that depolymerize PET have been found and enhanced by worldwide initiatives using various methods of protein engineering. Despite the achievements made in these works, it remains difficult to compare enzymes' performance and their applicability to large-scale reactions due to a lack of homogeneity between the experimental protocols used. Here, we pave the way for a standardized enzymatic PET hydrolysis protocol using reaction conditions relevant for larger scale hydrolysis and apply these parameters to four recently reported PET hydrolases (LCCICCG, FAST-PETase, HotPETase, and PES-H1L92F/Q94Y). We show that FAST-PETase and HotPETase have intrinsic limitations that may not permit their application on larger reaction scales, mainly due to their relatively low depolymerization rates. With 80% PET depolymerization, PES-H1L92F/Q94Y may be a suitable candidate for industrial reaction scales upon further rounds of enzyme evolution. LCCICCG outperforms the other enzymes, converting 98% of PET into the monomeric products terephthalic acid (TPA) and ethylene glycol (EG) in 24 h. In addition, we optimized the reaction conditions of LCCICCG toward economic viability, reducing the required amount of enzyme by a factor of 3 and the temperature of the reaction from 72 to 68 °C. We anticipate our findings to advance enzymatic PET hydrolysis toward a coherent assessment of the enzymes and materialize feasibility at larger reaction scales.

One-step electrodeposition of composition-controllable dendritic NiFe alloy electrocatalysts for oxygen evolution reaction

The development of cost-effective, highly stable, and efficient catalysts for the oxygen evolution reaction (OER) is a crucial step for large-scale industrial application of water electrolysis. This study introduces a facile and swift one-step electrodeposition method for the in-situ formation of dendritic NiFe alloy electrocatalysts supported on a nickel mesh. By fine-tuning the current density during electrodeposition, both the morphology and the nickel-iron ratio of the NiFe alloy can be optimized to enhance its OER performance. With an optimized nickel-iron ratio, the dendritic NiFe alloy catalyst demonstrates outstanding performance, achieving a current density of 10 mA·cm−2 at an overpotential of 242 mV in 1 M KOH solution, with a smaller charge transfer resistance (Rct) of 1.033 Ω and a low Tafel slope of 56.64 mV·dec−1. Moreover, the NiFe alloy catalyst exhibits good stability, maintaining a consistent current density of 10 mA·cm−2 over 30 h period with negligible fluctuations in overpotential. Moreover, at a current density of 50 mA·cm−2, the Faradaic efficiency for O2 achieves an impressive rate of 97.70%. This work presents a facile and efficient approach for the controlled synthesis of NiFe alloy OER electrocatalysts, providing a potential catalyst for industrial-scale water electrolysis applications.

Selective scaling-up of oscillating feedback micromixer: Characteristics and scaling criteria

Oscillating feedback micromixers (OFMs) can achieve efficient and rapid mixing passively by chaotic convection, and thus have broad application potential in microchemical engineering. As with most micromixers, the processing capacity of an OFM is extremely limited and cannot meet the requirements of large-scale industrial applications. Selective scaling of the OFM is essential to enable high throughput, rather than the numbering-up strategy, but no research has focused on this area. In this work, the Villermaux-Dushman reaction was employed to examine the mixing performance for a series of OFMs with different enlargement factors. The experimental results demonstrated that the OFM selectively scaled up still retains the advantages of micromixing, and its maximum flux can reach 14.4L/h with an acceptable pressure drop. Furthermore, the OFMs with different enlargement factors were investigated numerically to explore the characteristics and criteria of the selective scaling-up. The feedback ratio, residence time distribution (RTD), Euler number, and volume-averaged energy dissipation rate were utilized to characterize the hydrodynamics of these OFMs, and three scaling criteria concerning the pressure drop, RTD, and energy dissipation were first found. The three criteria can represent the scaling-up of OFMs regardless of the complicated and very different hydrodynamics. Finally, a generic scaling-up design guideline for OFMs is presented.

Treatment of seawater and wastewater using a novel low-cost ceramic membrane fabricated with red clay and tea waste

In wastewater treatment, the application of ceramic membranes has gained significant attention due to their potential for highly effective filtration. These membranes are typically produced using methods such as spin coating, dip-coating, and spray coating. However, these techniques have limitations when applied to large-scale industrial applications due to their high cost, time consuming process, and difficulty of control. Moreover, obtaining a complete and uniform coating typically requires several attempts. This research demonstrates the highly effective treatment of tannery wastewater using cost-effective porous ceramic membranes, by incorporating bio-based materials, such as tea waste, as porosifying additives into the main material, which is Moroccan red clay. Various analytical techniques, including X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), Thermogravimetric Analysis (TDA-TG), Scanning Electron Microscopy (SEM), and the Archimedes principle test, were used to investigate the properties of these ceramic membranes. The impact of the pore-forming agents on the membranes physical and mechanical properties, such as open porosity, bulk density, average pore diameter, flexural and indirect tensile strength, was evaluated. Filtration tests demonstrated effective removal of turbidity, suspended matter and chemical oxygen demand from the wastewater. The optimized membrane exhibited a permeability of 1249 L/h.m2.bar and turbidity removal efficiencies of 99.76% for seawater and 99.16% for tannery wastewater.

Heterogeneous interface engineering of cationic vacancy defects layered double hydroxides and molybdenum-nickel-based selenium compounds to facilitate overall water splitting

Constructing non-uniform interfaces of noble-metal-free electroactive materials is vital for the rapid kinetics and high ion/electron transfer rate towards overall water splitting. Herein, we propose a strategy to combine the cationic vacancy defects NiFe-LDH (VNFL) nanosheets with MoNiSe nanowires to design heterogeneous structures (MoNiSe@VNFL) grown on Ni foam (NF) for enhancement of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) electrocatalytic activity. Density flooding theory (DFT) calculations show that the electron transfer rate can be optimized by tuning electron dissipation and aggregation at the active site around the d-band centers near the Fermi energy level. As anticipated, even at a current density of 10 mA cm−2, the HER and OER occurring in these catalysts exhibit remarkable activity, with an rather low overpotentials of 27 mV, 200 mV and a Faradaic efficiency (FE) of almost 100 %. Notably, merely the cell overpotential of 1.56 V effectively propels a 10 mA cm−2 current density in the two-electrode architecture, as well with remarkable long-term stability for the water splitting, disclosing its potential in reduce the cost for large-scale industrial application.

Optimization of preparation of NaA zeolite from fly ash for CO2 capture.

The green synthesis method of fly ash-based NaA zeolite was explored to reduce the synthesis cost and environmental hazards. For the prepared NaA samples, the effects of crystallization time, solid-liquid ratio, and Si/Al ratio were systematically studied. CO2 adsorption isotherm is used for adsorption model fitting analysis and adsorption selectivity determination. According to the experimental results, the optimized NaA zeolite synthesis conditions are as follows: the Si/Al ratio of NaA zeolite is 1.4, the solid-liquid ratio is 10, and the crystallization time is 6 h. The green synthesis method reported in this study can successfully prepare NaA zeolite and exhibit excellent CO2 adsorption performance, reaching 4.34 mmol/g, with high CO2 selective adsorption ability, reaching 89.2 for N2, 257.1 for O2, and 45.8 for CH4. The adsorbed CO2 can be released for further utilization, and NaA zeolite also has strong adsorption and regeneration performance, with a ten cycle adsorption capacity only decreasing by 1.17%. In addition, the use of cheap raw materials synthesis methods will promote the large-scale industry application of green synthesis technology in the future.

Deactivation mechanism of CaO in a flow type dimethyl carbonate synthesis process

It is well known that calcium oxide (CaO) has better catalytic efficiency than most heterogeneous catalysts in many transesterification reactions. However, the gradual deactivation problem prevents its large-scale application in industry. In this paper, the deactivation mechanism of CaO in a fixed-bed reactor is investigated based on the transesterification reaction of propylene carbonate and methanol. The leaching amount of CaO during the reaction was estimated by the concentration of Ca in the products. The pretreated and recovered catalysts were characterized by FT-IR, XRD, TG-MS and SEM-EDS. It is evident from experiments and characterization that the deactivation process of CaO is accompanied by the leaching of calcium species and the generation of CaCO3, which are also verified by DFT calculations. At high temperature and high weight hourly space velocity, the deactivation was attributed to the formation of dense CaCO3 shell, which prevents the contact between the feedstock and the active species inside.

Numerical thermal study of ternary nanofluid influenced by thermal radiation towards convectively heated sinusoidal cylinder

ApplicationsThe heat transfer remains a huge problem for industrialists and engineers because many production processes required considerable amount of heat to finish the process successfully. Although, conventional fluids have large scale industrial applications but unable to provide huge amount of heat transfer. Therefore, the study is organized to propose a new ternary heat transfer model using different physical constraints. The key applications area of nanofluid heat transfer are chemical, applied thermal and food processing engineering. Purposeand Methodology: The key purpose of this research is introduce a new ternary nanofluid model using the impressive effects of thermal radiations, surface convection and saddle/nodal points. The results simulated via RKF-45 and discussed in detail. Core findingsThe strength of Al2O3 nanoparticles form 1%–7% (keeping fixed CuO and Cu as 4% and 6%) and s1 = −0.2,-0.4,-0.6,-0.8 controlled the fluid movement while s1 = 0.2,0.4,0.6,0.8 boosted the velocity. Increasing the convection process Bi = 0.1,0.2,0.3,0.4 increased the temperature significantly. Further, shear drag is maximum for ternary nanofluid and thermal radiations Rd = 0.1,0.2,0.3,0.4 enhances the heat transfer rate.

Comparison of the Performance of Mini Generator Water Turbines in Series and Parallel Flow Systems

The need for electricity is crucial in modern life, but the depletion of fossil fuel resources and their negative impact on the environment has led to the need for alternative, sustainable, and renewable energy sources. One of the most widely used renewable energy sources is hydro energy, which can be harnessed through the use of water turbine generators. This research aims to design, prototype, and test the performance of a mini-series and parallel water turbine generator system with a 24-volt system. Furthermore, this research will evaluate the difference in performance between the series and parallel systems and analyze the efficiency of the mini-series and parallel water turbine generator system. The focus of this research is on the efficiency of the water turbine generator system with variations in water flow, but it does not cover large-scale industrial applications. This research aims to provide sustainable and environmentally friendly energy sources as an alternative to conventional energy sources. The results of this research can serve as a reference for researchers and practitioners interested in the development of renewable energy sources, particularly water turbine generators. In the testing, the Series Turbine Series Generator system with a water flow rate of 6.38 L/min produced a maximum power of 2.43 watts, while the Parallel Turbine Series Generator system with a water flow rate of 13.01 L/min produced a maximum power of 2.142 watts. The efficiency ratio between the Series Generator and Parallel Generator is 1.5, with the Series Generator achieving a maximum efficiency of 38.6% in the Series Turbine Series Generator system, and the Parallel Generator achieving a maximum efficiency of 25.3% in the Series Turbine Parallel Generator system.

Hydrogen production and utilization in oil and gas facilities

The transition to hydrogen as a cleaner energy carrier within oil and gas facilities presents a promising opportunity to reduce carbon emissions and promote sustainable energy practices. This review investigates the potential for hydrogen production and utilization in oil and gas operations, focusing on hydrogen-powered equipment and fuel cells as alternatives to conventional carbon-intensive technologies. The research explores the feasibility of integrating hydrogen into oil and gas processes, examining its role in decarbonizing operations through the replacement of diesel generators, compressors, and other machinery. Hydrogen production methods such as steam methane reforming (SMR) with carbon capture and storage (CCS) and electrolysis using renewable energy are analyzed to assess their viability in large-scale industrial applications. Additionally, the use of hydrogen fuel cells is explored as a means to provide reliable, low-emission energy for various on-site applications, including power generation, transportation, and heating. The review highlights both the technical and economic challenges associated with hydrogen adoption in oil and gas facilities, such as infrastructure development, hydrogen storage, and distribution. However, it also emphasizes the long-term benefits, including reduced greenhouse gas emissions, compliance with global environmental regulations, and improved operational efficiency. By investigating hydrogen’s role as a cleaner energy carrier, this research contributes to the ongoing discourse on transitioning the oil and gas industry towards more sustainable and environmentally friendly practices.