Advanced Powder Technology最新文献

{"title":"On the phenomenon of shear wave velocity faster than that of compression wave induced by particle shape","authors":"Chengbo Li ,&nbsp;Peng Zhang ,&nbsp;Lin Bao ,&nbsp;Chuang Zhao","doi":"10.1016/j.apt.2025.104974","DOIUrl":"10.1016/j.apt.2025.104974","url":null,"abstract":"<div><div>This study provides a series of ellipsoidal aggregates in which the shear wave travels faster than the compressional one as the shape becomes more oblate. The propagation of elastic wave is simulated by the discrete element method, and the velocity is calculated by the time-of-flight method. An increase in the aspect ratio <em>α</em> leads to a significant reduction in the velocities of both compression (P) and shear (S) waves. As <span><math><mrow><mi>α</mi><mo>&lt;</mo><mn>6</mn></mrow></math></span>, the compression wave velocity is bigger than the shear wave velocity. However, when <span><math><mrow><mi>α</mi><mo>&gt;</mo><mn>6</mn></mrow></math></span>, the shear wave velocity becomes the faster one. According to the anisotropy coefficients of different ellipsoidal assemblies, the phenomenon of a faster shear wave is explained, and the equivalent propagation direction is also calculated. It is not that the shape induces a larger shear modulus, but rather that the variation in shape causes elastic waves to preferentially propagate along specific contact points, where the contact normals are similarly oriented. This normal vector is referred to as the equivalent propagation direction. As <span><math><mrow><mi>α</mi></mrow></math></span> increases, the equivalent propagation direction of the shear wave becomes more aligned with the vertical (height) direction of the sample, whereas the direction of the compression wave changes less significantly and tends to stabilize. A closer direction implies a shorter propagation path and a faster velocity. This study demonstrates a distinctive acoustic property induced by shape, which provides references for probing the interior structure of granular material by elastic waves. It also gives an idea to construct material in which wave can propagate along the designated path.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 8","pages":"Article 104974"},"PeriodicalIF":4.2,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144502795","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":"Research on discrete element construction and parameter calibration of agglomerated particles in moist-mix shotcrete","authors":"Pengcheng Li ,&nbsp;Gang Pan ,&nbsp;Lianjun Chen ,&nbsp;Siyuan Zhang ,&nbsp;Rongmin Zhang","doi":"10.1016/j.apt.2025.104971","DOIUrl":"10.1016/j.apt.2025.104971","url":null,"abstract":"<div><div>The purpose of this paper is to achieve the discrete element construction and contact parameter calibration of agglomerated particles in moist-mix shotcrete. The morphological characteristics and particle size distribution of Mortar-group particles (Mgp) and Aggregate-agglomerates (Aa) under different water-cement ratios are measured, the discrete element parameters of agglomerated particles and discrete element construction of various forms of particle models are clarified, and the optimal combination of contact parameters of agglomerated particles in different experimental groups are screened. The results show that the significant influencing parameters of repose angle of concrete materials under different water-cement ratios are obtained, and the second-order regression model is established between repose angle and significant parameters. The optimal combination of four significant parameters when the water-cement ratio is 0.25: the rolling friction coefficient of Mgp-Mgp is 0.15, the surface energy of Mgp-Mgp is 0.96 J<strong>·</strong>m⁻², the static friction coefficient of Mgp-SP (Steel plane) is 0.56, and the surface energy of Aa-Aa is 2.30 J·m⁻². The relative errors of average repose angles between simulation and actual physical experiments are about 2.0 %. Validation test results indicate that the discrete element construction and contact parameter combination of agglomerated particles have strong reliability, which can provide a basis for particle model construction and contact parameter support for long-distance pneumatic conveying characteristics of moist-mix shotcrete.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 8","pages":"Article 104971"},"PeriodicalIF":4.2,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144502796","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":"Effect of ball milling on the surface chemical state of Al2O3 powders","authors":"Xiaopan Wu ,&nbsp;Wei Pan ,&nbsp;Chunming Zheng ,&nbsp;Dan Wang ,&nbsp;Chunlei Wan ,&nbsp;Yixiang Ou ,&nbsp;Yi Feng ,&nbsp;Qili Jiang ,&nbsp;Haoqi Wang ,&nbsp;Zhiqiang Che ,&nbsp;Yue Zhang ,&nbsp;Li Hou ,&nbsp;Wenping Yuan","doi":"10.1016/j.apt.2025.104978","DOIUrl":"10.1016/j.apt.2025.104978","url":null,"abstract":"<div><div>The present study investigates the effect of ball milling on the surface chemical state of 500 nm Al₂O₃ powders to enable low-temperature sintering of high-performance ceramics. FTIR spectra reveal Al-OH absorption peaks. Specifically, with increasing ball milling time, the amount of stable [AlO₆] groups and Al-O bonds decreases, while that of metastable [AlO₄] groups and Al-O–H bonds increases, as revealed by deconvolution of XPS and Raman spectra. TEM observations confirm interparticle necking between the milled Al₂O₃ particles, demonstrating the enhanced surface activation. Water adsorption isotherms at 298 K demonstrate higher adsorption capacity for activated powder than raw powder, with adsorption increasing with milling time. The optimal surface activation of the 500 nm Al₂O₃ powder is achieved via 3 h ball milling at 600 rpm, featuring reduced particle size, increased BET surface area, and enhanced water adsorption. This mechanochemical activation enables low-temperature densification of electronic ceramics and optimization of pore structure in catalytic supports, offering a novel strategy for sustainable manufacturing of high-performance Al₂O₃-based ceramics.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 8","pages":"Article 104978"},"PeriodicalIF":4.2,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144489892","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 GPU-accelerated CFD-VOF-DEM approach for modelling the wet grinding process in a SAG mill and the mill speed effects","authors":"Qixuan Zhu ,&nbsp;Yuqing Feng ,&nbsp;Peter Witt ,&nbsp;Warren Bruckard ,&nbsp;Yaoyu Li ,&nbsp;Runyu Yang","doi":"10.1016/j.apt.2025.104975","DOIUrl":"10.1016/j.apt.2025.104975","url":null,"abstract":"<div><div>Semi-autogenous grinding (SAG) mills are essential for cost-effective rock beneficiation, primarily utilizing wet milling processes. Although the milling process has been extensively studied by DEM modelling, the effect of slurry is frequently neglected due to its complex interactions with the charge. This paper presents an efficient CPU-GPU framework for CFD-DEM modelling of the gas–liquid-solid flows during the wet grinding in a 34′ SAG mill. The model, which adopts a VOF approach to simulate the free surface between gas and liquid slurry phase, was comprehensively validated across four different cases, including particle sedimentation, phase conservation, and particle dynamics in both dry and wet drums. The validated model was used to simulate multiphase interactions in a SAG mill at various rotation speeds.</div><div>The milling process stabilized after 20 s, with the bed showing a kidney shape, characterized by the cascading zone and cataracting stream. The slurry flow, enveloped by the particle bed, exhibited a strong recirculating flow following the particle trajectories. The inclusion of slurry resulted in weaker and fewer particle collisions, with the fluid force accounting for half of the total force acting on particles. The effect of the slurry on rock particles was greater than on ball particles due to the density difference. Power consumption mainly resulted from interactions between the lifter sides and particles, while the slurry consumed minimal power. Both collision energy and frequency significantly increased at higher mill speeds, which are also expected to cause more severe liner wear and increased power consumption.</div><div>The model provides an efficient framework for simulating dense particles interacting with multiple fluid phases. The findings elucidate the multiphase interaction mechanisms in the SAG mill and underscore the necessity of including slurry in simulations to accurately model the milling dynamics.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 8","pages":"Article 104975"},"PeriodicalIF":4.2,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144489893","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":"Probing the improved collecting ability of dodecyl phosphate/poly-amine cation-anion association collector towards scheelite","authors":"Wei Chen ,&nbsp;Qiqiao Liu ,&nbsp;Jing Qi ,&nbsp;Guangyi Liu","doi":"10.1016/j.apt.2025.104977","DOIUrl":"10.1016/j.apt.2025.104977","url":null,"abstract":"<div><div>Efficient flotation of scheelite is very important for the safety of tungsten resources. A brand new collector, i.e., cation–anion association, was designed by mixing potassium dodecyl phosphate (MAP-K) with amines including diethylenetriamine (DETA), triethylene tetramine (TETA) and tetraethylenepentamine (TEPA). The collecting performance of these cation–anion association collectors toward scheelite were systematically studied through micro-flotation, zeta potential, contact angle and adsorption capacity detection. The micro-flotation results implied that cation–anion association collector TTK (MAP-K and TETA at 2:1 M ratio) performed excellent collecting ability toward scheelite, and the recovery reached to 97.53% under concentration of 5.0×10⁻⁴ mol/L TTK, while that was only 70.37% with MAP-K. It was found that the zeta potential of TTK-treated scheelite was positive shifted, implying that the amino group was protonated in cation–anion association of TTK. The positively charged TTK may have an electrostatic attraction of scheelite, facilitating the adsorption of phosphate groups in TTK on scheelite surface. The adsorption energy of the TTK (−11.082 eV) was nearly the twice that of MAP⁻ (−5.072 eV). Therefore, DETA facilitated the adsorption of MAP-K on scheelite and strengthened the hydrophobicity of scheelite.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 8","pages":"Article 104977"},"PeriodicalIF":4.2,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144470704","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":"Effects of external nitrogen sources on the electrochemical properties of nitrogen-doped carbon materials from bio-oil distillation residue","authors":"Jing-tao Li ,&nbsp;Dong-hong Nan ,&nbsp;Qing-xi Qu ,&nbsp;Yi-Yang Zhang ,&nbsp;Xi Luo ,&nbsp;Qi Niu ,&nbsp;Dan Yan ,&nbsp;Qiang Lu ,&nbsp;Kai Li","doi":"10.1016/j.apt.2025.104980","DOIUrl":"10.1016/j.apt.2025.104980","url":null,"abstract":"<div><div>Bio-oil distillation residue is a potential material for the production of activated carbon (AC) owing to the high carbon content and low ash content. The exogenous nitrogen sources have significant effects on the characteristics of nitrogen-doped AC. However, the relationship between nitrogen sources and the performances of nitrogen-doped AC remains ambiguous. In this study, four representative nitrogen sources, piperazine, urea, melamine, and polyaniline, are carefully selected to investigate their effects on the physicochemical and electrochemical properties of nitrogen-doped AC. The results show that the introduction of nitrogen sources increases the nitrogen contents of ACs, with the doping capacity ranked from the highest to the lowest as follows: polyaniline (5.42 wt%), piperazine (1.43 wt%), urea (1.28 wt%), melamine (0.92 wt%). Furthermore, compared to the specific surface area (SSA) of the AC without nitrogen-doping (1454.20 m²/g), the introduction of piperazine, urea, and melamine leads to increases in SSA, measuring 1552.69 m²/g, 1832.56 m²/g, and 1928.11 m²/g, respectively. However, the introduction of polyaniline decreases the SSA to 795.60 m²/g. The nitrogen-doped AC prepared by melamine shows excellent electrochemical properties, whose specific capacitance reaches 350F/g in 1 mol/L H₂SO₄ three-electrode system with a current density of 1 A/g.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 8","pages":"Article 104980"},"PeriodicalIF":4.2,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144366001","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":"Preparation of phosphogypsum-based explosion suppressant to reduce the severity of dust explosions","authors":"Qingwu Zhang ,&nbsp;Xun Zou ,&nbsp;Jianpeng Zhang ,&nbsp;Yuhang Bi ,&nbsp;Changxin Li ,&nbsp;Yajie Bu ,&nbsp;Yuan Yu ,&nbsp;Juncheng Jiang","doi":"10.1016/j.apt.2025.104976","DOIUrl":"10.1016/j.apt.2025.104976","url":null,"abstract":"<div><div>This study utilizes industrial waste phosphogypsum (PG) leachate as the raw material to prepare a magnesium ammonium phosphate (MAP) powder suppressant through reaction system adjustment and coprecipitation reactions, achieving the recycling and reuse of waste materials. The impact of the MAP powder suppressant on the explosion of nitrile butadiene rubber (NBR) dust was investigated in a 20-L spherical explosion vessel and a 1.2-L Hartmann tube. The results indicated that MAP has significant suppression effect on NBR dust explosion. When 70 % MAP was added, the maximum explosion pressure (P_max) of NBR dust decreased from 4.8 to 1.55 bar, and the explosion index (K_St) dropped from 35.75 to 10.61 bar·m·s⁻¹. When 90 % MAP was added, the NBR dust explosion can be completely suppressed. Additionally, with the addition of 50 % MAP, the ignition time of NBR dust was delayed by 7 ms, the duration from the maximum flame moment of the dust explosion to complete flame extinction decreased from 515 to 306 ms, and both the flame brightness and flame area were also reduced. Thermal analysis research showed that the explosion suppression mechanism of MAP powder suppressant is mainly through physical and chemical aspects, including effects of physical barrier, endothermic cooling and consumption of free radicals.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 8","pages":"Article 104976"},"PeriodicalIF":4.2,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144366000","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":"Effect of thermal treatment on hydrophilic/hydrophobic structure of hollow silica nanoparticles","authors":"Yuki Nakashima ,&nbsp;Hirokazu Katsui ,&nbsp;Satoru Kawase ,&nbsp;Tatsuki Ohji ,&nbsp;Manabu Fukushima","doi":"10.1016/j.apt.2025.104969","DOIUrl":"10.1016/j.apt.2025.104969","url":null,"abstract":"<div><div>Hollow silica nanoparticles (HSNPs) having inner cavity and porous silica shell were prepared using polyacrylic acid/ammonium hydroxide templates, and the effects of thermal treatment on their structural and hydrophilic/hydrophobic properties were investigated. As the temperature of the thermal treatment increased the number of micropores within the silica shell decreased, whereas the inner cavity (mesopores) of the HSNPs remained unchanged up to 900 °C. The change in the microstructure led to a reduction in the specific surface area (SSA) of the HSNPs. At 1100 °C, a sharp decline in SSA was observed, accompanied by partial collapse of the inner cavity and necking between particles, indicating sintering had occurred. The number of surface silanol groups decreased with increasing temperature, forming hydrophobic siloxane bonds because the silanol groups were close enough to react with each other.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 8","pages":"Article 104969"},"PeriodicalIF":4.2,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144330096","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":"Effect of MoS2 lubricant content on percolation behaviour in powder compression","authors":"Wei Zhang,&nbsp;Xu Gong,&nbsp;Weichang Wu,&nbsp;Chenkang Lin,&nbsp;Kewen Cheng,&nbsp;Rongxin Chen,&nbsp;Guofu Lian","doi":"10.1016/j.apt.2025.104967","DOIUrl":"10.1016/j.apt.2025.104967","url":null,"abstract":"<div><div>Considering the influence of lubricant content on the densification quality of the compactor, the percolation behaviour between particles, and the changes in mechanical behaviour among them, powder pressing was performed using a universal testing machine to verify the effect of the infiltration behaviour of solid particle lubricants on compaction and mechanical performance. The test results reveal that the transverse percolation of lubricant particles at the top of the compacted metal powder becomes more pronounced during the pressing process. Additionally, as the lubricant content increases, the intensity of particle percolation also increases. MoS₂ solid particle lubricants improve the density, hardness, and porosity of the compact and significantly enhance the densification. However, excessive lubricant leads to agglomeration, which reduces the compressibility of the compacted metal powder. This research expands the theories of powder forming mechanics and particle percolation, providing valuable guidance for further improving the densification of metal powder compacts.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 8","pages":"Article 104967"},"PeriodicalIF":4.2,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144321034","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":"Experimental investigation of coarse coal slime fluidization characteristics in three-phase fluidized beds","authors":"Yiqing Zhang ,&nbsp;Jincheng Liu ,&nbsp;Qinglin Yin ,&nbsp;Wenlong Meng ,&nbsp;Shihao Ding ,&nbsp;Yaowen Xing","doi":"10.1016/j.apt.2025.104973","DOIUrl":"10.1016/j.apt.2025.104973","url":null,"abstract":"<div><div>The gas-liquid-solid fluidized beds are highly effective for the separation of coarse coal slime, but their hydrodynamic behavior requires further clarification. This study investigates flow regimes based on real-time pressure fluctuation signals measured using micro-pressure sensors. A comprehensive analysis of pressure signal dispersion was conducted through pressure fluctuation curves and probability density functions. The critical liquid velocity for fluidization was identified at approximately 6*10⁻³ m/s, based on inflection points in pressure drop-velocity curves. Fixed beds exhibit elevated standard deviation, skewness, and kurtosis, signifying instability and non-uniformity, whereas fluidized beds display markedly lower time-domain values. Further refinement of flow regime classification can be achieved through frequency domain analysis, which provides enhanced characterization of particle and bubble dynamics within the fluidized bed system. Fluidized beds exhibit low overall pressure fluctuation energy, with power concentrated in low-frequency regions (&lt;10 Hz) at low gas velocities. When the gas velocity exceeds 1.5*10⁻³ m/s, energy shifts toward higher frequencies (10–20 Hz), reflecting intensified bubble turbulence. This analysis facilitates the further delineation of fluidized bed into the bubble dispersion regime and particle turbulence regime. The investigation of fluidization characteristics clarifies the environmental features in fluidized flotation, thereby laying a solid foundation for further experimental exploration and mechanistic studies of mineral separation in three-phase systems.</div></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":"36 8","pages":"Article 104973"},"PeriodicalIF":4.2,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144312627","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}