Powder Technology最新文献

{"title":"Experimental study on the mechanism of typical flame retardants in suppressing the explosion of phthalic anhydride dust","authors":"Qingwu Zhang ,&nbsp;Yanhui Wang ,&nbsp;Qingjun Xia ,&nbsp;Xundong Zhang ,&nbsp;Zhangwei Huang ,&nbsp;Yajie Bu ,&nbsp;Yuan Yu ,&nbsp;Juncheng Jiang","doi":"10.1016/j.powtec.2025.121478","DOIUrl":"10.1016/j.powtec.2025.121478","url":null,"abstract":"<div><div>Phthalic anhydride (PA), a critical chemical intermediate in polymer production, presents significant dust explosion hazards due to its fine particle size and high-temperature processing requirements. This study investigates the explosion characteristics of PA dust through experiments performed in the 20-L explosion device, 1.2-L Hartmann tube, and G-G furnace. The suppression mechanisms of three inert dusts, ammonium polyphosphate (APP), melamine polyphosphate (MPP), and melamine cyanurate (MCA) are also analyzed. At dust concentration of 1400 g/m³, PA exhibited the most severe explosion hazards: maximum explosion pressure (P_max) of 7.83 bar, deflagration index (K_St) of 164.19 bar·m/s, minimum ignition energy (MIE) of 100 mJ, and minimum ignition temperature (MIT) of 670 °C. The suppression tests revealed that all three inhibitors suppressed PA's explosion intensity with increasing mass fractions. Notably, APP and MPP outperformed MCA, achieving complete suppression at 40 wt% and 50 wt%, respectively, due to their dual-phase action: (1) physical suppression via heat absorption and formation of phosphorus-rich char layers isolating unburned particles, and (2) chemical suppression through radical scavenging (H•/OH•) and oxygen dilution by non-flammable gases (NH₃, H₂O). In contrast, MCA primarily suppressed explosions via gas-phase mechanisms by releasing NH₃/HNCO but lacked effective solid-phase char formation. Thermogravimetric and FTIR analyses further demonstrated that APP/MPP delay PA pyrolysis and enhance thermal stability, while residual char layers mitigate further combustion. This work provides critical insights into explosion inhibitor selection for PA dust explosion prevention, emphasizing the superiority of phosphorus-based inhibitors in industrial applications.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"466 ","pages":"Article 121478"},"PeriodicalIF":4.6,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144739348","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}

{"title":"Is there a “right” particle size and shape measurement tool?: A comparative study of seven online and offline devices on nine different particle populations","authors":"Daniel Biri ,&nbsp;Anna Jaeggi ,&nbsp;Oleksandr Prykhodko ,&nbsp;William Hicks ,&nbsp;Giulio Perini ,&nbsp;Marco Mazzotti ,&nbsp;Ashwin Kumar Rajagopalan","doi":"10.1016/j.powtec.2025.121405","DOIUrl":"10.1016/j.powtec.2025.121405","url":null,"abstract":"<div><div>Accurate characterization of the particle size and shape distribution (PSSD) of particle ensembles is essential for effective design, modeling, and control of crystallization processes. Despite the wide range of techniques available for the measurement of PSSDs, there is a noted gap in the literature concerning a comparative analysis of these methods when characterizing PSSDs. To this end, five commercial and two bespoke techniques were used to characterize nine particle ensembles. The evaluated instruments include Mettler Toledo’s FBRM and EasyViewer, BlazeMetrics’ probe, Malvern’s Laser Diffraction and Morphologi; alongside a stereoscopic imaging device (DISCO) and a confocal microscopy device (Petroscope). Test samples include small, medium, and large spherical glass beads with known size ranges; small and large sodium chloride cubes obtained through sieving; two populations of needle-like <span>d</span>-mannitol crystals; plate-like adipic acid crystals; and agglomerated <span>l</span>-Glutamic acid crystals. The results show that online devices generally disagree with each other, with offline devices, and with independent size references such as sieve fractions. For equant particles, offline devices exhibit good agreement with each other and independent size references. However, discrepancies arise for non-equant crystals (i.e. needles, plates). Only the Morphologi, DISCO, and Petroscope offer 2D characterization (length and width), while only the non-commercial bespoke techniques, i.e. DISCO and Petroscope, provide 3D characterization (length, width, and thickness). Comparing the measured PSSDs reveal small differences between the two bespoke devices. The outcomes from this study will inform practitioners on the strengths and limitations of PS(S)D characterization techniques and in turn their selection for specific applications.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"466 ","pages":"Article 121405"},"PeriodicalIF":4.6,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724008","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}

{"title":"Undesired agglomeration in agitated filter dryers: A critical review","authors":"Suruthi Gnanenthiran ,&nbsp;Christopher Hewitt ,&nbsp;Pari Rao ,&nbsp;Kate Pitt ,&nbsp;James Litster ,&nbsp;Rachel Smith","doi":"10.1016/j.powtec.2025.121425","DOIUrl":"10.1016/j.powtec.2025.121425","url":null,"abstract":"<div><div>Agitated filter dryers (AFDs) are commonly used in many industries, however the mechanisms driving undesired agglomeration remain poorly understood. Undesired agglomeration can have several consequences, including out of specification product, equipment damage, additional downstream processing and increased cycle times and cost. This review explores the influence of key material and process parameters on agglomeration in AFDs, highlighting the lack of mechanistic understanding that has hindered the development of accurate predictive models.</div><div>To address this, insights from wet granulation are applied to propose a novel mechanism consisting of three rate processes governing agglomeration during agitated drying: (1) formation of loosely bound agglomerates, (2) consolidation and coalescence, and (3) solidification of liquid bridges. The review examines how various parameters influence each rate process in this mechanism, offering a more predictive framework for agglomeration behaviour.</div><div>Additionally, existing modelling efforts for AFDs are reviewed, revealing that many studies focus on heat transfer while neglecting agglomeration. Comparisons with wet granulation models highlight opportunities to integrate established agglomeration and scale-up approaches into AFD models. By advancing the mechanistic understanding, this work aims to improve prediction, control, and scalability of agglomeration in agitated drying.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"466 ","pages":"Article 121425"},"PeriodicalIF":4.6,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750475","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}

{"title":"Impact of inlet flow rate on dynamic liquid film thickness and flow stability in spiral concentrator","authors":"Huizhong Liu ,&nbsp;Jian Wang","doi":"10.1016/j.powtec.2025.121472","DOIUrl":"10.1016/j.powtec.2025.121472","url":null,"abstract":"<div><div>The dynamic behavior of liquid films, particularly thickness variations, critically governs separation efficiency in spiral concentrators. During operation, flow instabilities in specific concentrator designs trigger periodic rolling waves that significantly alter hydrodynamic characteristics and particle transport. Notably, this phenomenon remains underexplored in mineral processing research. Through integrated experimental and computational fluid dynamics (CFD) simulations, we systematically investigated rolling wave dynamics in industrial-scale spiral concentrators. Our findings demonstrate that wave morphology correlates with trough geometry, surface flow regimes, and particle transport characteristics at the base. Inlet flow rate (Q) emerged as a pivotal control parameter: at Q = 9 L/min, waves exhibited maximum amplitude but minimal frequency and stability; Q = 11 L/min yielded optimal waveform stability; while Q = 13 L/min generated peak Froude numbers (<em>Fr</em> ≈ 2.83), following a unimodal trend mirroring wave height evolution. Crucially, periodic waves modulate near-wall shear rates, inducing Bagnold force fluctuations that govern particle loosening. Elevated velocity gradients at Q = 9/13 L/min promoted significant particle agitation and segregation through ±38 % Bagnold force variations, whereas stabilized shear rates at Q = 11 L/min enabled uniform particle flow. This study offers significant insights into the distribution and motion characteristics of particles under rolling wave conditions.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"466 ","pages":"Article 121472"},"PeriodicalIF":4.6,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144721382","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}

{"title":"Numerical investigation on agglomeration of reduced iron ore powders in a fluidized bed and the inhibiting effects of non-adhesive additives","authors":"Ruo Nan Dang,&nbsp;Xiang Jun Liu","doi":"10.1016/j.powtec.2025.121482","DOIUrl":"10.1016/j.powtec.2025.121482","url":null,"abstract":"<div><div>Fluidized direct reduction of iron ore particles is a potential technology for clean production of ironmaking. Agglomeration and de-fluidization of particles is a key problem for its application. In this study, a comprehensive CFD-DEM mathematical model for two-phase flow of reduced iron ore particles and high temperature gases in a fluidized bed is established, including a time and temperature dependent expression of solid bridge forces among reduced iron ore particles. A comparative study of solid bridging forces on flow and aggregation is conducted, revealing the detailed agglomeration behaviors. Effects of non-adhesive additives on inhibiting agglomeration are investigated. The addition of non-adhesive particles effectively reduces the proportion and size of agglomerates in beds, and a 15 % addition amount is suggested in this study. By adding non-adhesive particles, the working velocity interval can be extended towards lower gas velocities, and the working temperature interval towards higher temperatures.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"466 ","pages":"Article 121482"},"PeriodicalIF":4.6,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724107","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}

{"title":"Simulation method of the functional density cellular automaton for non-uniform flow in bubbling fluidized beds","authors":"He Kun ,&nbsp;Zheng Zhong","doi":"10.1016/j.powtec.2025.121479","DOIUrl":"10.1016/j.powtec.2025.121479","url":null,"abstract":"<div><div>This paper presents a functional density cellular automaton model that conveniently expresses the clustering effect between gas and solid phases. The study simulates the settlement process of single particles and validates the correctness and effectiveness of the functional density approach for gas-solid interactions by comparing with findings in existing literature. The model also investigates the fluidization states of solid particles under varying gas and solid densities. Results indicate that solid particles experience fluctuating resultant forces due to the combined effects of gravity and drag. The magnitude of resultant force increases with solid density, while initially decreasing and then increasing with gas density. When solid particles rise within the fluidized system, their force fluctuations diminish overall. The new model offers unique advantages in characterizing the microscopic behavior of gas-solid interactions in fluidized systems, providing new insights into fluidization mechanisms.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"466 ","pages":"Article 121479"},"PeriodicalIF":4.6,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144739347","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}

{"title":"A novel ballast roughness index for characterizing the surface undulation anisotropy and its application in directional friction of replicated ballast surfaces","authors":"Lihua Xue ,&nbsp;Junhua Xiao ,&nbsp;Jiapei Ma ,&nbsp;Kaichao Wang ,&nbsp;Yunbo Huo","doi":"10.1016/j.powtec.2025.121457","DOIUrl":"10.1016/j.powtec.2025.121457","url":null,"abstract":"<div><div>The friction coefficient of ballast particles is a critical parameter influencing the dynamic stability of ballasted beds. Currently, friction tests are commonly used to study ballast friction behavior. However, the anisotropy of surface roughness causes significant directional variations in friction coefficients. Conventional roughness indices fail to adequately capture these features, hindering quantitative correlations between friction coefficients and surface morphology. To address this issue, this study analyzed the statistical characteristics of surface roughness anisotropy from 584 real ballast particles. Based on the findings, a comprehensive roughness index was proposed, incorporating surface undulation amplitude, inclination and its anisotropy. The validity of the proposed index was confirmed through a comparison with conventional roughness indices. Then, the new roughness index was applied to ballast friction tests conducted along orthogonal directions. A linear correlation was identified between the index and the friction coefficients in the corresponding directions. In addition, the directional difference in friction was found to decrease with increasing normal load, indicating a reduced influence of roughness under higher stress conditions.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"466 ","pages":"Article 121457"},"PeriodicalIF":4.6,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144758068","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}

{"title":"Development of a high shear wet granulation regime map for the controlled agglomeration of heat sensitive amorphous food powders","authors":"Yashodh H. Karunanayake ,&nbsp;Linda Brütsch ,&nbsp;Vincent Meunier ,&nbsp;Gerhard Niederreiter ,&nbsp;Agba D. Salman","doi":"10.1016/j.powtec.2025.121470","DOIUrl":"10.1016/j.powtec.2025.121470","url":null,"abstract":"<div><div>If not controlled, temperature and humidity may induce caking of amorphous food powders that can be a major issue during food granulation. Caking must be avoided because it results in the permanent loss of material and process failure. The impact of key process parameters to achieve controlled particle agglomeration by avoiding caking in a High Shear Granulator was assessed across a range of Maltodextrins. Findings reveal that increasing impeller speed, batch size and run time promoted the rate of heat generation in the system. The resulting increase in bed temperature was found to impact the different Maltodextrin powders to varying extents depending on the powder T_g, with high DE Maltodextrins showing greater sensitivity to temperature increases. This study also highlighted that high DE Maltodextrins require less water for effective granulation. This behavior correlated with the rate at which the water binder's viscosity increases as it incorporates Maltodextrin during granulation. High DE Maltodextrins demonstrated slower viscosity rises with increased solid composition than low DE counterparts, producing binder systems that remains mobile and adhesive at higher solid contents, thereby facilitating more efficient granulation. A parameter <span><math><msub><mi>k</mi><mi>μ</mi></msub></math></span> was modelled to reflect this relationship. The parameters (T- T_g) and <span><math><mfenced><mrow><mi>L</mi><mo>/</mo><mi>S</mi></mrow></mfenced><mo>/</mo><msub><mi>k</mi><mi>μ</mi></msub></math></span> were then used to produce a caking regime map for the High Shear Granulation system. This regime map delineates an optimal region for controlled agglomeration and a region where a high likelihood of caking occurs. The threshold of this caking region was set at a T-Tg of 40 °C and <span><math><mfenced><mrow><mi>L</mi><mo>/</mo><mi>S</mi></mrow></mfenced><mo>/</mo><msub><mi>k</mi><mi>μ</mi></msub></math></span> value of 0.0325.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"466 ","pages":"Article 121470"},"PeriodicalIF":4.6,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144739351","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}

{"title":"Pressure-driven dynamic sintering mechanism and fracture failure mode in bimetallic surface coating composite interfacial nanoparticle","authors":"Weishan Lv ,&nbsp;Jianwei Lv ,&nbsp;Suhang Wei ,&nbsp;Jiaxin Liu ,&nbsp;Cai Chen ,&nbsp;Yong Kang","doi":"10.1016/j.powtec.2025.121476","DOIUrl":"10.1016/j.powtec.2025.121476","url":null,"abstract":"<div><div>Understanding the underlying sintering diffusion mechanism and mechanical failure modes of bimetallic surface coating nanoparticles under pressure-driven sintering can promote the synthesis and application of die-attach materials. In this paper, we innovatively proposed a continuous molecular dynamics (MD) method to reveal the fusion mechanism and surface mechanical response of Cu@Ag bimetallic surface coating composite nanoparticles under pressure-assisted sintering. The results indicate that the thickness of the coating and the sintering temperature have a synergistic regulatory effect on the sintering kinetics and structural evolution. There is a critical threshold for the thickness of the coating, which can significantly regulate the topological evolution of diffusion paths through the formation of stacking faults and dislocations. The sintering temperature affects the competitive mechanism between dislocation proliferation and slip by adjusting the diffusion activation energy. The triple coupling mechanism of “diffusion-interface-deformation” in bimetallic composite materials was first elucidated through uniaxial tensile simulation. Changing the thickness of coating can regulate the diffusion path and interface stress state, combined with the activation effect of sintering temperature on the deformation mechanism, jointly inducing the evolution of the material from brittle fracture to ductile fracture and then to adhesive fracture. This study provides new theoretical basis for design of coating nanoparticle materials, especially the discovery of critical thickness effects and coupling mechanisms, advancing high performance die-attach materials.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"466 ","pages":"Article 121476"},"PeriodicalIF":4.6,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724106","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}

{"title":"Eco-friendly composite dust suppressant based on Enteromorpha cellulose: Preparation, characterization and dust suppression mechanism","authors":"Jinfeng Wang ,&nbsp;Qimeng Zhao ,&nbsp;Zhixin Wei ,&nbsp;Xu Chen ,&nbsp;Jia Ding ,&nbsp;Wenbin Zhao","doi":"10.1016/j.powtec.2025.121477","DOIUrl":"10.1016/j.powtec.2025.121477","url":null,"abstract":"<div><div>In addressing the issue of excessive dust generation during coal mining and transportation, as well as the detrimental impact of Enteromorpha (EP) outbreaks on marine ecosystems, an eco-friendly composite dust suppressant (CPPS) has been developed. This suppressant is created through the carboxymethylation modification of EP cellulose, which serves as the matrix, and incorporates polyvinyl alcohol (PVA) and polyacrylamide (PAM) as monomers. Using consolidation strength as the performance metric, the optimal compounding conditions for the dust suppressant at 60 °C were established through orthogonal experiments. The ideal ratio of the components PVA, PAM, and SDBS was determined to be 10:1:4, resulting in a consolidation strength of 77.3 HA for the optimal formulation. Under a simulated wind speed of 12 m/s, the dust suppression rate of the formulated product remains above 95 %. Furthermore, the contact angle between CPPS and the coal cake is reduced by 34 % in comparison to traditional dust suppressants. After 9 h, the water retention of the coal sample treated with CPPS stabilizes at approximately 18 %. Simulations using Materials Studio software indicate that CPPS enhances the infiltration of water molecules into coal dust and improves the adhesion between water and coal dust. This research is significant for the advancement of environmentally friendly composite dust suppressants and supports sustainable environmental practices.</div></div>","PeriodicalId":407,"journal":{"name":"Powder Technology","volume":"466 ","pages":"Article 121477"},"PeriodicalIF":4.6,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144721487","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}