Powder Technology最新文献_第6页

Study on the gas-solid flow and reaction characteristics of oxy-fuel co-firing of coal and biomass in a pressurized fluidized bed by 3D Eulerian-Lagrangian modelling

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-14 DOI: 10.1016/j.powtec.2025.120808

Qinwen Liu , Wenqi Zhong , Aibing Yu

{"title":"Study on the gas-solid flow and reaction characteristics of oxy-fuel co-firing of coal and biomass in a pressurized fluidized bed by 3D Eulerian-Lagrangian modelling","authors":"Qinwen Liu , Wenqi Zhong , Aibing Yu","doi":"10.1016/j.powtec.2025.120808","DOIUrl":"10.1016/j.powtec.2025.120808","url":null,"abstract":"<div><div>The oxy-fuel co-firing of coal and biomass in a pressurized fluidized bed (POFB), which integrates the benefits of pressurized oxy-fuel combustion, fluidized bed technology, and biomass as a carbon-neutral fuel, has been identified as a promising and innovative approach for low-cost CO<sub>2</sub> capture and environmentally friendly waste disposal. However, experimentation and numerical simulations remain both challenging and limited. In this study, a 3D Eulerian-Lagrangian model based on the MP-PIC scheme was further developed, and was validated through our continuously running 10 kW<sub>th</sub> POFB tests. The effects of the combustion pressure (<em>P</em>) on gas–solid flow and reaction characteristics were analysed. The results showed that the model accurately predicted flow structure, temperature, and composition of CO<sub>2</sub>, CO, O<sub>2</sub>, NO, N<sub>2</sub>O, and SO<sub>2</sub>, under both atmospheric and pressurized combustion. When <em>P</em> increased, the POFB operated under both the CH mode (i.e., unchanged flow structure and heat input) and IH mode (i.e., unchanged local apparent gas velocity but increased heat input) constructed favourable gas–solid flow and chemical reaction conditions. Notably, increasing <em>P</em> under the IH mode enhanced the uniformity of the particle distribution along the axial direction and radial ring-core structure. The results demonstrated that increasing <em>P</em> not only led to a better temperature distribution and higher CO<sub>2</sub> concentration in the flue gas but also reduced pollutants emissions. Overall, this study advanced the development of numerical models and obtained a series of results that are difficult to achieve through experiments, offering valuable support for the design, optimisation, and scaling up of POFB.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"456 ","pages":"Article 120808"},"PeriodicalIF":4.5,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143519205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Study on dust exposure levels and respiratory particle deposition patterns of workers in respirable dust environments 可吸入粉尘环境中工人的粉尘暴露水平和呼吸道颗粒沉积模式研究

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-14 DOI: 10.1016/j.powtec.2025.120802

Gang Zhou , Zengxin Liu , Guochao Yan , Jingxu Chen , Biao Sun , Jianjun Yao , Xiangyan Zhang , Hanxu Guo

{"title":"Study on dust exposure levels and respiratory particle deposition patterns of workers in respirable dust environments","authors":"Gang Zhou , Zengxin Liu , Guochao Yan , Jingxu Chen , Biao Sun , Jianjun Yao , Xiangyan Zhang , Hanxu Guo","doi":"10.1016/j.powtec.2025.120802","DOIUrl":"10.1016/j.powtec.2025.120802","url":null,"abstract":"<div><div>Quantifying the deposition of respirable dust in the respiratory tract under coal mining production conditions is essential for effectively improving industrial dust control technologies and developing occupational protective equipment. This study designed a series of test experiments to investigate dust exposure, with a focus on the impact of inhalable dust dispersion on the respiratory tracts of workers. The overall study encompassed three main components: the setup of respiratory parameters, fluorescence tracing experiments, and particle deposition tests in the respiratory tract. The validation of the experiments was carried out using bidirectional coupling simulations based on CFD-DEM. The study tested the performance of common dust-proof masks in coal mining using an occupational disease detection platform. The results indicate that the overall particle deposition is highest in the lobar bronchi, with the deposition rate in the right lobar bronchi showing the most significant variation with particle size. For particles smaller than 10 μm depositing in the respiratory tract, inertial impaction is the dominant factor. This phenomenon becomes more pronounced with increasing breathing intensity. The increase in flow velocity facilitates the dispersion and dilution of particles. The deposition rate of 1 μm particles is hardly influenced by breathing intensity. For particles smaller than 5 μm, the escape rate exceeds 90 %.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"456 ","pages":"Article 120802"},"PeriodicalIF":4.5,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Research on the mechanism of sediment erosion in the bucket of a large-scale Pelton turbine at a hydropower station

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-14 DOI: 10.1016/j.powtec.2025.120805

Jitao Liu , Xiaobing Liu , Xiao Chang , Bei Qin , Jiayang Pang , Zhenming Lai , Dengyun Jiang , Mengjun Qin , Bing Yao , Yongzhong Zeng

{"title":"Research on the mechanism of sediment erosion in the bucket of a large-scale Pelton turbine at a hydropower station","authors":"Jitao Liu , Xiaobing Liu , Xiao Chang , Bei Qin , Jiayang Pang , Zhenming Lai , Dengyun Jiang , Mengjun Qin , Bing Yao , Yongzhong Zeng","doi":"10.1016/j.powtec.2025.120805","DOIUrl":"10.1016/j.powtec.2025.120805","url":null,"abstract":"<div><div>Turbine sediment erosion, which often leads to a reduction in turbine efficiency, damage to Pelton turbine, a reduction in operational stability (especially for 100 MW–500 MW turbines), and frequent overhauling, is a serious problem in plants with high sediment concentrations in the water, resulting in considerable economic losses. Hence, research into sediment erosion in Pelton turbines in sandy rivers aims to uncover the mechanism behind the sediment erosion of Pelton turbines. This investigation holds significant implications for the design and operation of Pelton hydropower plants to combat sediment erosion. In this study, a model turbine with a runner diameter of 400 mm was developed. Through numerical simulations of the model turbine's internal flow and the prediction of sediment erosion, the study analyzed the distribution of sediment volume fraction (concentration) on the bucket's working surface during the intake, retention, and discharge stages, as well as the sediment velocity distribution. Furthermore, the impact of silt particle size on sediment erosion in the Pelton turbine bucket was examined. The effects of silt and water velocity and metal material on the sediment erosion of Pelton turbine buckets were determined through sediment erosion tests, in conjunction with internal flow simulation results. Thus, the sediment erosion mechanism of Pelton turbine buckets was elucidated.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"455 ","pages":"Article 120805"},"PeriodicalIF":4.5,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143438037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Vibration and wear assessment of slurry TBM discharge pipeline transporting large sized rock particles: CFD-DEM-FEM multifield coupled simulation

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-14 DOI: 10.1016/j.powtec.2025.120801

Yingran Fang , Xinggao Li , Yidong Guo , Dalong Jin , Hongzhi Liu

{"title":"Vibration and wear assessment of slurry TBM discharge pipeline transporting large sized rock particles: CFD-DEM-FEM multifield coupled simulation","authors":"Yingran Fang , Xinggao Li , Yidong Guo , Dalong Jin , Hongzhi Liu","doi":"10.1016/j.powtec.2025.120801","DOIUrl":"10.1016/j.powtec.2025.120801","url":null,"abstract":"<div><div>The circulation system of the slurry Tunnel Boring Machine (TBM) plays a pivotal role in delivering the slurry to the excavation face and transporting the excavated rock particles to the ground. The severe vibration and significant wear induced by the transportation of large-sized particles in pressure pipelines constitute a complex multiphysics coupling problem. In this study, a numerical model of pressure pipeline conveying large-size rock particles is established based on CFD-DEM-FEM multifield coupling method with the background of a slurry TBM construction in Beijing. The engineering measured pipeline pressure loss and vibration data verified the reasonableness of the multifield coupling model. The U.S. pipeline vibration standard is introduced to systematically evaluate the vibration intensity of slurry TBM circulating pipeline. The effects of particle mass flow rate, particle size, slurry flow speed, slurry viscosity, pipeline wall thickness and fixed spacing on pipeline vibration and wear are investigated, and suggestions for the control of vibration and wear reduction in the circulating pipeline are proposed. The relevant conclusions can provide a reference for the long-term operation of slurry TBM circulation pipelines under complex geological conditions.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"455 ","pages":"Article 120801"},"PeriodicalIF":4.5,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143438036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Suppression effect and mechanism of melamine polyphosphate /zinc borate composite suppressant on aluminum dust explosion

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-13 DOI: 10.1016/j.powtec.2025.120777

Shuqi Zhang , Jiangping Zhao , Yong Yang , YaChao Wang , Kainan Yu

{"title":"Suppression effect and mechanism of melamine polyphosphate /zinc borate composite suppressant on aluminum dust explosion","authors":"Shuqi Zhang , Jiangping Zhao , Yong Yang , YaChao Wang , Kainan Yu","doi":"10.1016/j.powtec.2025.120777","DOIUrl":"10.1016/j.powtec.2025.120777","url":null,"abstract":"<div><div>To mitigate potential hazards of aluminum (Al) powder explosions, a green suppressant called MPP/ZB has been successfully produced using mechano-chemical technology. The suppressant consists of melamine polyphosphate (MPP) and zinc borate (ZB). This study examined the suppression effect of various mass concentrations of the composite suppressant on Al dust explosion. The results indicate that, with the addition of 100 wt% of MPP/ZB to the 300 g/m<sup>3</sup> aluminum powder, P<sub>max</sub> and K<sub>st</sub> decreased from 0.701 MPa and 8.7 MPa·m/s to 0.13 MPa and 0.2 MPa·m/s, respectively, effectively suppressing the explosions. Moreover, TG-DSC analysis of the suppressant and XPS/SEM examination of the explosion residues further revealed that the addition of ZB enhances the inhibitory effect of MPP on Al dust explosions. The H<sub>2</sub>O, Zn (OH)<sub>2</sub> and ZnO produced by ZB decomposition reduce the concentration of NH<sub>3</sub> generated by MPP decomposition, which may have a combustion promoting effect on Al dust.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"456 ","pages":"Article 120777"},"PeriodicalIF":4.5,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143550820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Theoretical analysis and numerical simulation of the gas-solid hydrodynamics in pressurized bubbling fluidized beds

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-13 DOI: 10.1016/j.powtec.2025.120789

Dong Yan , Hongzhong Li , Qingshan Zhu , Zheng Zou

{"title":"Theoretical analysis and numerical simulation of the gas-solid hydrodynamics in pressurized bubbling fluidized beds","authors":"Dong Yan , Hongzhong Li , Qingshan Zhu , Zheng Zou","doi":"10.1016/j.powtec.2025.120789","DOIUrl":"10.1016/j.powtec.2025.120789","url":null,"abstract":"<div><div>The heterogeneous structure is considered to improve the theoretical prediction of gas-solid hydrodynamics in pressurized bubbling fluidized beds. The two-fluid simulation shows that the traditional unmodified Gidaspow model overestimates the gas-solid coefficient and bed expansion. As a comparison, the simulations which consider the meso-scale structures predict the reduced gas-solid drag coefficients and the reasonable bed expansions especially at high superficial gas velocities. The decrease in the dimensionless gas-solid drag coefficient with the elevated pressure indicates that the drag modification based on the heterogeneous structure is essential. The parameter sensitivity analysis demonstrates that the effect of the elevated pressure on the gas-solid drag force should be mainly attributed to the changes in minimum fluidization velocity, while the bubble behaviors contribute slightly. Moreover, the gas-solid slip velocity shows a surprisingly uniform distribution, which verifies the dynamic steady state of gas-solid interaction in bubbling fluidized beds.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"455 ","pages":"Article 120789"},"PeriodicalIF":4.5,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143454488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

Real-time film thickness monitoring in complex environments using deep learning-based visual imaging

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-13 DOI: 10.1016/j.powtec.2025.120795

Liang Zhong , Hengqiang Cheng , Lele Gao , Lian Li , Wenping Yin , Hui Wang , Qiyi Miao , Yunshi Zhang , Lei Nie , Hengchang Zang

{"title":"Real-time film thickness monitoring in complex environments using deep learning-based visual imaging","authors":"Liang Zhong , Hengqiang Cheng , Lele Gao , Lian Li , Wenping Yin , Hui Wang , Qiyi Miao , Yunshi Zhang , Lei Nie , Hengchang Zang","doi":"10.1016/j.powtec.2025.120795","DOIUrl":"10.1016/j.powtec.2025.120795","url":null,"abstract":"<div><div>Film thickness is a critical quality attribute of coated pharmaceutical pellets, as it directly influences drug release profiles and stability. In fluidized bed coating processes, accurate in-line measurements are challenging with traditional imaging methods under complex conditions, such as high material density, pellet overlap, and defocusing. Therefore, this paper introduces an innovative visual imaging strategy leveraging the Mask R-CNN algorithm for non-invasive, real-time film thickness monitoring during fluidized bed coating processes. The proposed approach achieves precise pellet segmentation and effectively addresses challenges posed by pellet overlap, defocusing, and blurring. The superiority and accuracy of the Mask R-CNN algorithm were validated against traditional methods such as Otsu thresholding, Canny edge detection, and off-line techniques, including UV–visible spectrophotometry and laser diffraction. The sensitivity and robustness of the proposed approach were further explored under conditions of high contamination, overexposure, and low contrast arising from color variations. The results of this study demonstrate the potential of deep learning-based imaging to transform process analytical technology (PAT), facilitating dynamic and precise quality monitoring in pharmaceutical production.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"456 ","pages":"Article 120795"},"PeriodicalIF":4.5,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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

PLA/PBAT composite powder prepared by thermally induced phase separation for selective laser sintering

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-13 DOI: 10.1016/j.powtec.2025.120799

Wanjun Li , Dongming Zou , Binling Chen , Yuan Wang

引用次数: 0

Damage evolution of UHPC under coupled high stress, temperature, and osmotic pressure: New multi-field experiment and non-destructive techniques

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-12 DOI: 10.1016/j.powtec.2025.120793

Zhiyong Liu , Yunsheng Zhang , Gan Liu , Yuncheng Wang , Wanhao Yu , Jinyang Jiang

{"title":"Damage evolution of UHPC under coupled high stress, temperature, and osmotic pressure: New multi-field experiment and non-destructive techniques","authors":"Zhiyong Liu , Yunsheng Zhang , Gan Liu , Yuncheng Wang , Wanhao Yu , Jinyang Jiang","doi":"10.1016/j.powtec.2025.120793","DOIUrl":"10.1016/j.powtec.2025.120793","url":null,"abstract":"<div><div>Underground structures in deep regions of ocean underground engineering are exposed to high stress, temperature, and osmotic pressure, which accelerate their damage and degradation. This work investigates the performance of ultra-high-performance concrete (UHPC) under these coupled conditions using a specially designed load-temperature-osmotic pressure coupling instrument. The damage evolution of UHPC was evaluated using ultrasonic pulse velocity (UPV), bulk density, and scanning electron microscopy (SEM). The results show that increasing the stress ratio causes greater damage to the UHPC while the damage and cracks in the UHPC under high temperatures and osmotic pressure are instead repaired. In addition, the number, width, and length of microcracks in UHPC increase with the increasing water-binder ratio. Reducing the water-cement ratio to 0.16 and incorporating 2 % steel fibers can result in the best performance in terms of damage resistance. These findings provide valuable insights into the application of UHPC in challenging underground structures in deep regions of ocean underground engineering.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"455 ","pages":"Article 120793"},"PeriodicalIF":4.5,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143427526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 barrel shape study for a twin-screw conveyor using the Discrete Element Method

IF 4.5 2区工程技术

Powder Technology Pub Date : 2025-02-12 DOI: 10.1016/j.powtec.2025.120744

D. Rhymer, A. Ingram, C.R.K. Windows-Yule

{"title":"A barrel shape study for a twin-screw conveyor using the Discrete Element Method","authors":"D. Rhymer, A. Ingram, C.R.K. Windows-Yule","doi":"10.1016/j.powtec.2025.120744","DOIUrl":"10.1016/j.powtec.2025.120744","url":null,"abstract":"<div><div>An effective barrel design is critical for successful material transport in a twin-screw conveyor. However, geometric parameter studies are often overlooked because of their increased complexity over studying scalar parameters due to the cost of manufacturing multiple bespoke components. In recent years, advances in computing power have made simulations an attractive and low-cost method of conducting geometric parameter studies. Here a Discrete Element Method (DEM) study compares the effectiveness of eight barrel geometries in a twin-screw conveyor. The results showed that the industry-accepted figure-of-eight cylinder design was the most effective for particle transport with the greater interaction between the screw and barrel reducing the material throughput time by over 40% compared to other designs. However, alternatives might become attractive if certain specifications were desirable. A design with rounded sides and a flat centre is worse at conveying by 22% compared to the figure-of-eight but there is 15% less net force acting on the particles and similar amounts of mixing. Finally, parameter testing shows that the results will at least be qualitatively consistent across a wide range of the parameter space and should therefore be valid for most materials.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"455 ","pages":"Article 120744"},"PeriodicalIF":4.5,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143422295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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