Chemical Engineering Research & Design最新文献_第9页

Largest Lyapunov exponent and Shannon entropy: Two indices to analyze mixing in fluidized beds 最大李雅普诺夫指数和香农熵：分析流化床混合的两个指数

IF 3.7 3区工程技术

Chemical Engineering Research & Design Pub Date : 2024-08-22 DOI: 10.1016/j.cherd.2024.08.026

{"title":"Largest Lyapunov exponent and Shannon entropy: Two indices to analyze mixing in fluidized beds","authors":"","doi":"10.1016/j.cherd.2024.08.026","DOIUrl":"10.1016/j.cherd.2024.08.026","url":null,"abstract":"<div><p>The quality of mixing in fluidized beds greatly influences performance in many applications. Assessing quality of mixing involves measuring the mixing rate and evaluating the bed mixedness. Quantifying the bed mixedness is typically done using mixing indices. However, the application of existing mixing indices to fluidized beds can be problematic due to aeration and complications from the particle phase in the Two-Fluid Model (TFM).</p><p>The objectives of this study are twofold. First, the largest Lyapunov exponent is proposed to quantify mixing in fluidized beds. Its effectiveness is shown on a mono-disperse bed with varying gas velocities. The increase in mixing rate with higher gas velocity is accurately represented by the largest Lyapunov exponent. Second, the Shannon entropy mixing index is adopted to quantify the bed mixedness for TFM results. This index is tested on a bi-disperse bed to predict segregation and evaluate the effect of bed composition and superficial gas velocity on this process. The effect on segregation is reflected in the entropy components: distributional entropy showed minimal variation, whereas conditional entropy was significantly affected. Evaluating bed mixedness at different length scales showed that increasing bin spatial resolution slightly reduced conditional entropy. The results are validated against experimental data.</p></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0263876224005045/pdfft?md5=f00977a778425751a911febc65d2ceed&pid=1-s2.0-S0263876224005045-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142087820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental and simulation studies on suppressing gas explosions with diverse atomized liquid droplets: Insights for improved safety in mining 利用多样化雾化液滴抑制瓦斯爆炸的实验和模拟研究：提高采矿安全的启示

IF 3.7 3区工程技术

Chemical Engineering Research & Design Pub Date : 2024-08-21 DOI: 10.1016/j.cherd.2024.08.018

{"title":"Experimental and simulation studies on suppressing gas explosions with diverse atomized liquid droplets: Insights for improved safety in mining","authors":"","doi":"10.1016/j.cherd.2024.08.018","DOIUrl":"10.1016/j.cherd.2024.08.018","url":null,"abstract":"<div><p>Gas explosions represent a prevalent thermodynamic hazard in coal mining, significantly endangering worker safety and the operation's overall safety. Water mist stands out among various explosion suppression techniques due to its high heat absorption capacity and environmental sustainability, offering a promising avenue for application. This study introduces a custom-built pipeline gas explosion testing apparatus to investigate the suppression effects of different atomized liquid droplets on gas explosions. By collecting and analyzing experimental data from pressure sensors under varying conditions within the pipeline, we conduct a thorough comparison of the explosion suppression characteristics attributed to different atomized droplets. Based on this foundation, the Fluent software was used for numerical simulation research to further analyze the explosion suppression effects of different atomized droplets. Additionally, numerical simulations were conducted to optimize the nozzle arrangement. Our findings reveal that an increase in atomization pressure, leading to smaller droplet sizes, significantly mitigates the impulse of the gas explosion shock wave. This indicates a marked inhibitory effect of atomized droplets on gas explosions, with finer droplets showing enhanced suppression capabilities. The simulation results from the optimized nozzle arrangement can provide valuable guidance for on-site deployment. Through a combination of experimental and simulation data, this study conducts a qualitative and quantitative analysis of the suppression mechanisms offered by different atomized droplets, considering parameters such as explosion impulse, blast energy, and explosion indices. The insights gained provide a theoretical foundation for reducing the ring-breaking effect of gas explosions and enhancing explosion suppression strategies, which are crucial for ensuring the safety of coal mining operations.</p></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142075950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Whey protein and maltodextrin conjugated foam-mat dried honey powder: Functional, physicochemical, structural, rheological and thermal characterization 乳清蛋白和麦芽糊精共轭泡沫垫干蜂蜜粉：功能、理化、结构、流变和热特性分析

IF 3.7 3区工程技术

Chemical Engineering Research & Design Pub Date : 2024-08-20 DOI: 10.1016/j.cherd.2024.08.015

{"title":"Whey protein and maltodextrin conjugated foam-mat dried honey powder: Functional, physicochemical, structural, rheological and thermal characterization","authors":"","doi":"10.1016/j.cherd.2024.08.015","DOIUrl":"10.1016/j.cherd.2024.08.015","url":null,"abstract":"<div><p>Honey in its natural form possesses considerable challenges in mass production and transportation owing to its viscosity and stickiness, making it prone to crystallization over time. Dried honey powder makes it convenient for handling and processing. In this study, foam mat dried powder (FMDP) was obtained by foam mat drying technique in which whey protein isolate (WPI) and maltodextrin (MD) were used as foaming agent and foam stabilizer, respectively. The obtained FMDP was characterized in terms of physical, chemical, functional, phytochemical, rheological and structural properties to study the impact of foaming agents. WPI was found to improve the functionality, stability and glass transition temperature and on the other hand, MD was found to enhance the stability, crystallinity and the color of the FMDP. FTIR helped in understanding the changes in the functional groups attributed to the foaming agents. The crystallinity and the microstructural changes in the FMDP were observed from X-ray diffractograms and SEM micrographs, respectively. The rheological characterization confirmed the viscous nature of honey. The study confirmed the interaction between proteins and polysaccharides, which subsequently improved the heat stability, functional properties, solubility, emulsifying capacity, antioxidant properties, and solubility. The dried honey samples demonstrated minimal caking, low cohesiveness (Hausner ratio: 1.16 ± 0.027–1.29 ± 0.041), good and fair flowability (ranging between 14.25 ± 2.02–22.52 ± 2.25). Therefore, it can be concluded that during this study, protein and polysaccharide conjugate FMDP was obtained with better quality attributes, which can be further incorporated during various product development in food industries.</p></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142013086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Segmented distribution of gas diffusion layer porosity and catalyst layer ionomer content in a polymer electrolyte membrane fuel cell 聚合物电解质膜燃料电池中气体扩散层孔隙率和催化剂层离聚物含量的分段分布

IF 3.7 3区工程技术

Chemical Engineering Research & Design Pub Date : 2024-08-14 DOI: 10.1016/j.cherd.2024.08.014

{"title":"Segmented distribution of gas diffusion layer porosity and catalyst layer ionomer content in a polymer electrolyte membrane fuel cell","authors":"","doi":"10.1016/j.cherd.2024.08.014","DOIUrl":"10.1016/j.cherd.2024.08.014","url":null,"abstract":"<div><p>Gas diffusion layer porosity and ionomer content inside catalyst layer both can affect cell performance. Electrochemical reaction rate is non-uniform inside the cell. Non-uniform design of components or structures can improve the electrochemical reaction rate distribution and thus promote cell performance. Thus, the investigations on the optimal distribution are done using the optimization solver within COMSOL Multiphysics 5.3a to seek the optimal segmented distribution of porosity or ionomer content to obtain higher current density. The distributions in cathode side along three directions are all investigated. The optimized results show that the porosity increases along main gas flow direction and the ionomer content reduces. With voltage decreasing, the value of porosity around outlet region reduces and the value around outlet region increases, ionomer content shows opposite trend. The porosity under gas channel is higher than that under land. Ionomer content increases under land and reduces under gas channel with voltage decreasing. The porosity is high near catalyst layer and ionomer content near proton exchange membrane is higher at low voltages. The ionomer content distribution along thickness direction can improve current density by 5.596 % at 0.2 V. For better overall cell performance, the porosity changing along x-axis can be selected, the values from under land to under gas channel are 0.384, 0.499, 0.618. These results can provide theoretical guidance for cell components design to obtain higher cell output performance.</p></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142040360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

CFD modeling using reactions kinetics for selective hydrogenation for acetylene in a fixed-bed reactor 利用固定床反应器中乙炔选择性加氢的反应动力学进行 CFD 建模

IF 3.7 3区工程技术

Chemical Engineering Research & Design Pub Date : 2024-08-13 DOI: 10.1016/j.cherd.2024.08.011

{"title":"CFD modeling using reactions kinetics for selective hydrogenation for acetylene in a fixed-bed reactor","authors":"","doi":"10.1016/j.cherd.2024.08.011","DOIUrl":"10.1016/j.cherd.2024.08.011","url":null,"abstract":"<div><p>Selective hydrogenation of acetylene (SHA) reactions is usually performed in fixed-bed reactors (FBR). The traditional SHA kinetics, when coupled with a three-dimensional computational fluid dynamics (CFD) model, requires improvement to accurately predict SHA reaction outcomes. The SHA microdynamics, when integrated with a three-dimensional CFD model, have not been comprehensively examined. In this paper, a mathematical model based on CFD was developed to simulate the reactive flow behavior of SHA in FBR using a novel OleMax100 catalyst. In this study, a 3D catalyst bed numerical simulation of FBR with coupled microdynamics description of conjugate heat transfer and surface catalytic reaction was carried out, and the accuracy of CFD at different Reynolds numbers (Re) was verified by experimental results, which showed a high degree of agreement between the model and experimental results. The effect of the ratio of tube to pellet diameter (D/d=N) on the fluid flow characteristics and SHA reaction in the bed was investigated, and the catalyst shape was considered. The simulation results show that an increase in N significantly improves the homogeneity of the flow field and the heat and mass transfer between the phases in the FBR, which leads to an increase in the conversion efficiency of acetylene. When N was increased from 4.00 to 6.67, the conversion was enhanced by 6.7 %. Increasing the Re value affects the reactivity, and the SHA reaction exists in a reaction zone where excessive residence time exacerbates the decrease in selectivity. The adopted and novel catalyst microkinetic models can provide some theoretical guidance for the optimal design of the SHA reaction and process improvement in FBR.</p></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142050450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Offline constrained reinforcement learning for batch-to-batch optimization of cobalt oxalate synthesis process 用于草酸钴合成工艺批次间优化的离线约束强化学习

IF 3.7 3区工程技术

Chemical Engineering Research & Design Pub Date : 2024-08-13 DOI: 10.1016/j.cherd.2024.08.013

{"title":"Offline constrained reinforcement learning for batch-to-batch optimization of cobalt oxalate synthesis process","authors":"","doi":"10.1016/j.cherd.2024.08.013","DOIUrl":"10.1016/j.cherd.2024.08.013","url":null,"abstract":"<div><p>The cobalt oxalate synthesis, a batch process, plays a crucial role in the refinement of cobalt metal. The mean particle size of cobalt oxalate is a critical indicator that reflects product quality. However, excessive ammonium oxalate solution flow can heighten waste disposal costs in the production process. To address these issues, we propose a novel offline reinforcement learning (RL) algorithm that guarantees compliance with constraints in the cobalt oxalate synthesis process, utilizing exclusively static datasets. This method employs cost critic networks to assess costs, transforming the constrained optimization problem into an unconstrained one by introducing Lagrangian multipliers. We use exponential moving average (EMA) to optimize the update of proportional integral derivative (PID) control multipliers, reduce overshoot and oscillation in the control process, and thus improve the overall stability of the system. Furthermore, to optimize algorithm performance, a deep residual network (DResNet) is integrated into the policy network. Experimental results indicate that the algorithm’s optimization policy performs significantly better under constraints.</p></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142013083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A model for hindered diffusion in pores 孔隙受阻扩散模型

IF 3.7 3区工程技术

Chemical Engineering Research & Design Pub Date : 2024-08-11 DOI: 10.1016/j.cherd.2024.08.010

引用次数: 0

Glycerol dry reforming over Ni supported on fibrous ZSM5 and ZY: Correlation of structural properties on H2 production 镍在纤维状 ZSM5 和 ZY 上的甘油干转化：结构特性与 H2 产量的相关性

IF 3.7 3区工程技术

Chemical Engineering Research & Design Pub Date : 2024-08-11 DOI: 10.1016/j.cherd.2024.08.012

{"title":"Glycerol dry reforming over Ni supported on fibrous ZSM5 and ZY: Correlation of structural properties on H2 production","authors":"","doi":"10.1016/j.cherd.2024.08.012","DOIUrl":"10.1016/j.cherd.2024.08.012","url":null,"abstract":"<div><p>This study investigates fibrous ZSM5 (FZSM5) and Zeolite Y (FZY) as supports for producing hydrogen via glycerol dry reforming. The fibrous ZSM5 and ZY were synthesized hydrothermally with microemulsion and impregnated with 10 wt% Ni via a sonication method. The catalytic test was conducted via a vertical stainless steel fixed-bed rig, at 800°C with a glycerol/CO<sub>2</sub> ratio of 1. XRD and N<sub>2</sub> sorption revealed the reduced surface area and crystallinity in Ni/FZSM5 compared to Ni/FZY. Ni/FZY catalyst displayed a larger surface area (264 m<sup>2</sup>/g) and aperture width (6.70 nm) in comparison to Ni/FZSM5, which had a surface area of 238 m<sup>2</sup>/g and an aperture width of 3.90 nm. Ni/FZY also had a smaller NiO crystallite size (8.73 nm) than Ni/FZSM5 (9.79 nm), suggesting well-dispersed Ni species on the wrinkle fiber of FZY’s surface. Ni/FZY outperformed Ni/FZSM5 with 52.49 % glycerol conversion, 44.87 % H<sub>2</sub> yield, 71.31 % CO yield, and only 14.4 % carbon formation, attributed to robust Ni-O-Si contact and larger pore diameter. The discovery highlights the catalytic efficiency of the Ni-loaded fibrous zeolite in GDR, offering versatility for application in energy storage and catalysis.</p></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142013085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Role of fabrication parameters on microstructure and permeability of geopolymer microfilters 制造参数对土工聚合物微滤器微结构和渗透性的影响

IF 3.7 3区工程技术

Chemical Engineering Research & Design Pub Date : 2024-08-10 DOI: 10.1016/j.cherd.2024.08.009

{"title":"Role of fabrication parameters on microstructure and permeability of geopolymer microfilters","authors":"","doi":"10.1016/j.cherd.2024.08.009","DOIUrl":"10.1016/j.cherd.2024.08.009","url":null,"abstract":"<div><p>A new method for preparing geopolymer filtrations was suggested, using silica fume in an alkali activator as an environmentally and economically sustainable material. The geopolymer filtration was fabricated by activating metakaolin with a blend of sodium hydroxide and silica fume. Different phase structures and microstructures were fabricated with varying preparation parameters, such as silica fume content, Na<sub>2</sub>O/Al<sub>2</sub>O<sub>3</sub> molar ratios, and curing temperatures. The filters were characterized using X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersion spectroscopy, and mercury intrusion porosimetry. Filters were tested for pure water flux, compressive strength, and wastewater permeability using industrial textile wastewater. The geopolymer-zeolite composite filter, including 10 wt% silica fume, Na<sub>2</sub>O/Al<sub>2</sub>O<sub>3</sub> molar ratio of 1, and curing temperature of 60 °C exhibited the highest pure water permeability of 144 L/m<sup>2</sup>.h.bar, wastewater permeability of 77 L/m<sup>2</sup>.h.bar, and achieved 95.5 % turbidity reduction for the textile wastewater.</p></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142136334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Particle motion characteristics of vertical pipe on a the horizontal-vertical pneumatic conveying system installed dune models in the different curvature elbows 在水平-垂直气力输送系统的垂直管道上安装不同曲率弯头的沙丘模型的颗粒运动特性

IF 3.7 3区工程技术

Chemical Engineering Research & Design Pub Date : 2024-08-09 DOI: 10.1016/j.cherd.2024.08.008

{"title":"Particle motion characteristics of vertical pipe on a the horizontal-vertical pneumatic conveying system installed dune models in the different curvature elbows","authors":"","doi":"10.1016/j.cherd.2024.08.008","DOIUrl":"10.1016/j.cherd.2024.08.008","url":null,"abstract":"<div><p>To minimize energy consumption in transportation, a dune model is developed and installed in elbow with varying radii of curvature in the horizontal-vertical pneumatic conveying system in this study. The experimental study focuses on the effect of dune model in elbow with different radius of curvature on the pneumatic conveying system in terms of pressure drop, additional pressure drop coefficient, and the power loss coefficient. Furthermore, the particle concentration and velocity distribution are measures by using the electrical capacitance tomography (ECT) and the high-speed particle image velocimetry (PIV) technology. Finally, the particle pulsation velocity is analyzed to reveal the particle motion mechanism of vertical pipe with dune model by using the fourier transform and wavelet transform. The results indicate that the minimum gas conveying velocity is reduced by installing the dune model, with a maximum reduction rate of 10.36 %, and the maximum reduction rate of power loss coefficient decreased is 11.56 %. At the same time, the particle concentration near the outside and inside wall of the pipe with dune is lower and higher than of without dune, and the particle axial velocities with dune are larger than the case of no dune, and the particle axial pulsation intensity with dune are larger than the case of no dune. Otherwise, the peak value of power spectrum of with dune is lower than that of no dune model in the low frequency region, and the wavelet fluctuation energy of low frequency has a great influence on the axial velocity of particles near the inside wall of pipe for the case of dune model.</p></div>","PeriodicalId":10019,"journal":{"name":"Chemical Engineering Research & Design","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142040361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0