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Water hyacinth (Eichhornia crassipes) is considered a prospective free-floating aquatic plant potentially used to address current issues on food, energy, and the environment. It can grow quickly and easily in various tropical and subtropical environments as long as it has access to adequate light and water to support photosynthetic growth. Ecosystems are threatened by their invasive growth and remarkable capacity for adaptation. However, managing this plant can result in valuable products. This paper demonstrates particle technologies that might be used to utilize water hyacinths, including brake pads, fertilizer, bioenergy, animal feed, phytoremediation agents, bioplastics, and adsorbents. This study is accompanied by a discussion based on the conducted experiments and currently available literature, providing readers with a clearer understanding. Water hyacinth's capacity to absorb macro- and micro-nutrients, nitrogen, and phosphorus makes it a good plant for phytoremediation. The prospect of producing cellulose makes it prospective as a biomass energy source and livestock feeding. Further, it can be transformed into high-cellulose content particles for applications in bioplastics, brake pads, and adsorbents. The current reports regarding education of water hyacinth to student also were added. Finally, issues and suggestions for future development related to the use of water hyacinths are discussed. This study is expected to provide comprehensive knowledge on how to turn invasive water hyacinth plants into valuable products. [ABSTRACT FROM AUTHOR]

One of the techniques used in extracting gold in small-scale gold mining is mercury amalgamation. However, the use of mercury presents significant health and environmental hazards, as well as suboptimal efficiency in gold extraction. This study explores the possibility of the use of rice husk as a prototype adsorbent for mercury removal from its leaching in mining environments. To support the analysis, the rice husk adsorbent was characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, electron dispersive X-ray spectroscopy, atomic absorption spectrophotometers and Brunauer − Emmett − Teller analysis. To investigate the removal of Hg from aqueous solutions, batch adsorption experiments were conducted, and the efficiency was optimized under various parameters such as contact time, rice husk dosage, and initial concentration of mercury. Kinetic and isotherm investigations were also carried out to gain a better understanding of the adsorption properties. The kinetic adsorption was analyzed using the pseudo-first-order and pseudo-second-order. Furthermore, the isotherm adsorption was analyzed using ten adsorption isotherm models (i.e., Langmuir, Freundlich, Temkin, Dubinin – Radushkevich, Flory – Huggins, Fowler – Guggenheim, Hill – de Boer, Jovanovic, Harkin – Jura, and Halsey). The amount of mercury absorption increased with increasing contact time, adsorbent mass, and initial concentration of mercury. The pseudo-second-order kinetic model is the best model that can be applied to describe the adsorption process. Analysis of the adsorption results obtained shows that the adsorption pattern is explained through the formation of a monolayer without any lateral interaction between the adsorbate and adsorbent. In addition, the formation of multilayers due to inhomogeneous pore distribution also occurs which causes a pore filling mechanism. We found that the isotherm phenomena are near the Jovanovic models with the maximum adsorption capacity) of rice husk found to be 107.299 mg/g. As a result, rice husk could be a promising option for wastewater treatment due to its fast and efficient removal capacity, as well as its affordability and eco-friendliness. The predicted thermodynamic studies using the Flory – Huggins isotherm model show that the adsorption process is endothermic, spontaneous, and physisorption. The impact shows that the utilization of rice husk can be used and fit for the current issues in the sustainable development goals (SDGs).

The advantages of using elements of games in educational contexts have been reported in literature since the times of Plato in ancient Greece. Modern studies credited games with some advantages in education from different angles (behavioural, motivational or cognitive). In this paper, the application of games that have an explicit and carefully thought-out educational purpose (serious games) in different chemical engineering subjects at the bachelor and master level is discussed. Firstly, some topic definitions are provided along with a historical perspective of the use of games in education and the theoretical foundations supporting it. In section 2, four different applications of games are presented in three different subjects. In particular, the use of board games for the subjects Process Control and Particle Technology is illustrated, and how the combination of simple games (e.g. crosswords) and escape room activities can help to develop both low level and high level skills (following the Bloom's taxonomy classification) in Optimisation of Chemical Processes is also presented. Their analysis and discussion of the impacts achieved with the different game-based activities are later presented in section 3 along with the main conclussions drawn. • Serious games can help to promote active learning, engagement, and motivation of chemical engineering students. • Different game-based activities were implemented to foster both low level and high level skills. • A comprehensive design to adapt the type and level of the games to the classroom is key to promote positive impacts. [ABSTRACT FROM AUTHOR]

This study aimed to develop the solid astaxanthin-encapsulated self-microemulsifying delivery system (S-AST SMEDS) spray-dried particles and investigate the effect of materials in formulations on product characteristics. The optimized liquid AST SMEDS incorporated with a polymeric precipitation inhibitor (PI) was solidified with a solid carrier by spray drying. Physicochemical properties of S-AST SMEDS spray-dried powders including morphology, particle size and distribution, flowability, solid-state characters, moisture content, yield, loading capacity of AST, and reconstitution properties were examined. Polymeric PIs seemed to have an impact on particles' size, surface smoothness, and flowability while solid carriers had an effect on the particles' moisture content and droplet size of microemulsions obtained after reconstitution. The amount of AST encapsulated in S-SMEDS powder was influenced by both polymer and solid carriers. Dissolution and short-term stability of S-AST SMEDS were also studied. Our developed spray-dried solid SMEDS particles helped enhance AST dissolution rate. [ABSTRACT FROM AUTHOR]

The size dependence of contact electrification (CE) for the same material particles is a common but poorly understood phenomenon. Generally, smaller particles acquire negative charges and larger particles positive charges. However, we discover that polyethylene particles can exhibit the opposite polarity under certain conditions. We demonstrate that the particle morphology, such as sphericity and surface roughness, plays a crucial role in determining the polarity, with more spherical and smoother particles being positively charged. This morphology effect can even alter the relative positions of materials in the triboelectric series. We propose a model that incorporates both the morphology and size effects to explain CE of the same material particles. The model successfully reproduces all our experimental results and predicts a nontrivial cyclic triboelectric sequence that we further confirm experimentally. This article reveals new insights into the nonequilibrium charge transfer mechanisms in CE. [ABSTRACT FROM AUTHOR]

Since the early 2010s, after decades of premature excitement and disillusionment, the field of artificial intelligence (AI) is experiencing exponential growth, with massive real-world applications and high adoption rates both in daily life and in industry. In particle technology, there are already many examples of successful AI applications, for predictive modeling, process control and optimization, fault recognition, even for mechanistic modeling. However, in comparison to its still untapped potential and to other industries, further expansion in adoption rates and, consequently, gains in productivity, efficiency, and cost reduction are still possible. This review article is intended to introduce AI and its application scenarios and provide an overview and examples of current use cases of different aspects and unit operations in particle technology, such as grinding, extrusion, synthesis, characterization, or scale-up. In addition, hybrid modeling approaches are presented with examples of the intelligent combination of different methods to reduce data requirements and achieve beneficial synergies. Finally, an outlook for future opportunities is given, depicting promising approaches, currently being in the conception or implementation phase.

In this article, we provide a comprehensive experimental, numerical, and theoretical explanation of the dry‐to‐wet transition of nonbonded fiber networks made of natural fibers. Given that the main functionality of many common products consisting of fluff pulp fiber networks requires absorption of liquids, we focus on understanding the solid volume fraction transition from a dry to a wet state as a crucial component for controlling properties such as permeability and capillary pressure, on which product function eventually depends. From studying the wetting of fluff pulp fiber networks with a distribution of fiber lengths, we show that the change in the solid volume fraction going from dry to wet state is driven by the disappearance of fiber–fiber adhesion. The mechanically stable state to which the network transitions is independent of its prior dry solid volume fraction and predetermined primarily by the fiber aspect ratio. [ABSTRACT FROM AUTHOR]

Summary: Infectious viral particles in bioaerosols generated during laparoscopic surgery place staff and patients at significant risk of infection and contributed to the postponement of countless surgical procedures during the COVID-19 pandemic causing excess deaths. The implementation of devices that inactivate viral particles from bioaerosols aid in preventing nosocomial viral spread. We evaluated whether electrostatic precipitation (EP) is effective in capturing and inactivating aerosolized enveloped and non-enveloped viruses. Using a closed-system model mimicking release of bioaerosols during laparoscopic surgery, known concentrations of each virus were aerosolized, exposed to EP and collected for analysis. We demonstrate that both enveloped and non-enveloped viral particles were efficiently captured and inactivated by EP, which was enhanced by increasing the voltage to 10 kV or using two discharge electrodes together at 8 kV. This study highlights EP as an effective means for capturing and inactivating viral particles in bioaerosols, which may enable continued surgical procedures during future pandemics.

Product quality is paramount for companies to maintain the trust from their customers. Powder products and in particular fertilizers can suffer damage during storage if the temperature and moisture are not appropriate. Most of the work has focused on drying, but the last stage of cooling is responsible for avoiding product out of specification. A first principles model has been developed for industrial fluidized vibrating cooling units following a multiscale approach, from the particle to the entire unit, to evaluate their operation. The unit consists of two sections using atmospheric and cool air, respectively. A refrigeration cycle is also modelled to compute the needs to cool the air. The unit's model only includes two adjustable parameters, the heat transfer efficiency from the particle to the air as well as for the losses from the unit to atmosphere. The model has been validated using industrial data, resulting in heat flow efficiency from the particle equal to 0.30 and the flow of losses of 1.17 kW/K. The model can reproduce the industrial data within reasonable error and allows predicting the cooling cycle needs and estimating the cost of its operation as a function of the weather. The location of the facility results in the fact that during June-August the atmospheric air cannot cool the product below the critical temperature and the refrigeration cycle needs to operate. • Product features determine the customer acceptance. • An industrial vibrocooling unit has been modelled and validated. • The model is based on first principles with few adjustable parameters. • The model allows predicting the unit operation over a year time. • June-August requires the use of the unit for the product to reach specifications. [ABSTRACT FROM AUTHOR]

Granular materials exhibit unique secondary flow behaviors upon shearing. We demonstrate, using particle dynamics simulations, that the secondary flow patterns are controlled by a pressure exerted on particle bed. A threshold pressure, at which vortex flow transitions to disturbed or chaotic flow, depends on particle shape, that influences interparticle contacts and rheological performance. Our results show that the flow patterns are essentially determined by a dimensionless term combining pressure and granular temperature for all the spherical and Platonic solid‐shaped particles explored. Particle mixing is promoted by the vortex flow or disturbed flow with strong diffusion. The highest mixing rate under a specified pressure is obtained for cubic particles, due to the significant microstructural ordering near the boundaries causing a high gradient of packing density. These findings shed light on how applied pressure and particle shape affect secondary flows which is critical to the understanding and control of granular mixing. [ABSTRACT FROM AUTHOR]

Methanol‐to‐olefin (MTO) conversion on zeolites has encountered severe coke deposition and rapid deactivation. Creating different levels of porosity is essential to mitigate such issues. Herein, we demonstrate a facile and green strategy to synthesize uniform and hierarchically macro/mesoporous ZSM‐5 microspheres by combining spray‐freeze drying and steaming‐assisted crystallization (SAC). The structure, crystallinity, and porosity of the zeolite microspheres are controlled by adjusting the water/gel mass ratio and time in the SAC process. The structure evolution during the SAC process is revealed. In the catalytic MTO reaction, the representative hierarchically porous ZSM‐5 catalyst exhibits superior catalytic performance. At a very high weight hourly space velocity of 18 h−1, it shows a dramatically prolonged lifetime (47 h at >99% conversion) and much‐improved selectivity to ethylene and propylene compared with the conventional microporous ZSM‐5 and nano‐sized ZSM‐5. The enhanced performance is originated from the hierarchical structure and suitable acidity of the ZSM‐5 microspheres. [ABSTRACT FROM AUTHOR]

In this essay, we discuss the evolution of particle technology in the context of climate change. We begin with a brief outline of the history of particle technology. In addition to the fascination of fine particle systems, it will become clear that particles have also been associated with negative consequences of human activities since the industrial revolution and still are. Some examples of how dispersive systems contribute to solving current challenges are discussed. Finally, we identify white fields and open questions in particle engineering in the context of climate change hoping that this will stimulate further research. [ABSTRACT FROM AUTHOR]

This article reviews the state of the art of the formulation and fabrication of sensible, latent, and thermochemical thermal energy storage (TES) materials with special focus on the role of particle technology in enhancing the performance of these materials. Molten salt‐based sensible TES materials have been intensively studied, particularly the use of doped nanoparticles for enhancing specific heat capacity and thermal conductivity. For latent TES, the inclusion of property enhancers is among the most effective approaches to address the low thermal conductivity and supercooling issues of phase change materials (PCMs), whereas the encapsulation of PCMs and structurally stabilized composite PCMs are the favorable methods to address leakage and chemical incompatibility challenges. Thermochemical TES materials are often incorporated with an inert or an active host matrix for structural stabilization. [ABSTRACT FROM AUTHOR]

• A one-step construction strategy of hollow porous PLA microparticles was proposed. • The hollow-porous particles were with fusiform, red blood cell and spherical shapes. • A formation map in terms of flow rate ratio and PLA concentration was obtained. • The release performance of irbesartan encapsulated in the particles were studied. • The particles exhibit sustained release performance and high encapsulation rate. Biodegradable hollow-porous microparticles have shown great potentials in chemical and biomedical areas owing to their distinctive structural attributes. Herein, a simple but instructive strategy was proposed to construct hollow-porous polylactic acid (PLA) microparticles in one-step based on electrohydrodynamic atomization technology. Hollow-porous microparticles with fusiform, red blood cell and spherical shapes were successfully fabricated with production rates of 70 mg/h, 30 mg/h and 105 mg/h. A formation map in terms of flow rate ratio and PLA concentration was obtained to demonstrate the operating regions. Effects of key operating parameters were studied, showing that high voltage (11.4 kV−12.4 kV) and low PLA concentration conditions (2.5 %−3.5 %) are preferred to get well-structured particles. The evolutions of Taylor cone and atomization state were also explored experimentally and numerically to further understand the process. The prepared microparticles exhibit excellent sustained release performance and high encapsulation rate (>90 %). This strategy offers a satisfactory one-step method for preparing various structured hollow-porous polymer particles as drug carriers. [ABSTRACT FROM AUTHOR]

A general expression for specific energy requirements in particle breakage is derived from a population balance model. The model employs power-law rate kernels, self-similar fragment distributions and an energy dependence based on the Vogel-Peukert master curve. This model connects the empirical constants and exponents of size in older empirical energy laws to the parameters of the population balance model, the nature of the particles, and certain moments of the self-similar particle size distribution predicted by the model. The resulting model is used to extract values of the order of the power-law rate kernel from literature data. The extracted order values are consistent with known expressions for individual particle breakage. The model developed here may be coupled with experimental determination of the material parameter needed in the Vogel-Peukert master curve to enable extraction of energy utilization efficiency values from experimentally determined values of the size-independent portion of the selection function. [Display omitted] • Population balance models give expressions that mirror older specific breakage energy "laws." • By contrast, the new expression's constants are linked to the model rather than being empirical. • The empirical laws have exponents on particle length scale of 0, ½ and 1. • The new expression's exponent varies with the order of the breakage rate kernel. • Analysis of literature data suggests exponents ranging from 0.85 to 2.78. [ABSTRACT FROM AUTHOR]

The mouth is a vital route of drug administration with over 84 % of all medicines reportedly administered through it. The gastrointestinal system is equally imbued with a lot of adaptive features that make the oral route even more conducive for systemic drug delivery. The usefulness of the oral route is, however challenged by the existence of numerous absorption barriers which limit the ef fective absorption and delivery of drugs to their target sites in the body systems. Understanding these adaptive attributes, systemic barriers, and available strategies for overcoming such barriers will not only be helpful in drug development and design but also useful to the formulation scientists desirous of optimizing drug delivery. The objective of this work was to review the gastrointestinal route of drug administration with respect to some biochemical and physio-anatomic features that impede or enhance drug absorption and to highlight current strategies that have been deployed to achieve optimum per oral drug delivery. The current review reveals the emerging roles of nanocarriers in oral drug delivery. Polymeric nanocarriers enhance the solubility, targeting and safety prof iles of many important pharmacological agents. Novel systems that of fer protection against gastro enzymes and as such, promote oral administration of biologicals are being widely investigated. Mechanical, magnetic, and acoustic energy – induced membrane perturbation are other delivery options receiving research attentions. It may be concluded that, with the avalanche of research ef forts in the area, the oral route will maintain its prominence among other routes of drug administration. [ABSTRACT FROM AUTHOR]

The very wide varieties of geometries of irregular particles makes it difficult to study their motion also propose a simple and general equation to estimate their drag coefficient (CD). The goal of this research is to (1) experimentally validate the general CD correlation previously proposed by the authors of this article as a simple tool to estimate the CD of spherical to highly irregular particles over a wide ranges of Re from 0.001 to 300,000, and (2) examine and expand the reference model particles proposed by the authors to represent a wide range of irregular shapes (60 non‐flat and 36 flat). A comparison between the CD experimentally measured using reference model particles over a range of Re from 9 to 2481 and the CD estimated using general CD correlation, also comparing with CD correlations by others, demonstrated the accuracy and simplicity of the proposed general CD correlation. [ABSTRACT FROM AUTHOR]

Particle filtration is a major building block in effluent treatment facilities for water reuse in agriculture, industry, and the community. Yet, its incorporation in modern hybrid treatment systems still lacks basic know-how for process optimization. This paper aims to provide a profound understanding of particle filtration vis-à-vis its various reuse applications. The methodology used follows a road map depicted as a growing tree, representing the author's research from roots to top: roots—basic modeling, mechanisms; tree trunk—filter design approach for reuse; branches—enhanced particle removal; and tree crown—pretreatment, bioparticle, and nanoparticle removal. Contact deep-bed filtration process optimization, algorithms for economically optimal filter design, tertiary filtration and membrane pretreatment, and related energy issues are being discussed. Some of the conclusions are that pilot plant planning should be primarily derived from particle surface interactions with filter media, based on measurements of mineral particle or bioparticle size, shape, and physicochemical characteristics, and applying attachment-detachment models. Filter design optimization would comprise of selecting efficient water quality processes first, followed by economic optimization for final design parameters. A holistic approach in the design of filtration facilities, standing alone or incorporated in hybrid systems, is also considered. [ABSTRACT FROM AUTHOR]

A second challenge with fluidized-bed catalysts in laboratory-scale fixed beds is the pressure drop resulting from the flow of gas through the packed bed of fine catalyst particles, which may violate the isobaric reactor ideality criterion. These issues have been identified by many investigators, resulting in the development of several alternative laboratory reactors for gathering information on fluidized-bed catalysts.39-41,57,62-64 An alternative to the MAT reactor for FCC catalyst testing is the advanced cracking evaluation (ACE) reactor.65 The ACE reactor is a small-scale fluidized bed with adjustable feed injection points to facilitate changes in residence time. Keywords: catalysis; circulating fluidized beds; fluidization; hydrocarbon processing; particle technology EN catalysis circulating fluidized beds fluidization hydrocarbon processing particle technology 1 9 9 08/17/22 20220901 NES 220901 INTRODUCTION The scientific community and public are expressing concerns regarding global stewardship and sustainability. Fluidized-bed reactor scale-up: Reaction kinetics required. [Extracted from the article]

As a new type of gas–liquid microreactors, the gas–liquid mini‐bubble column has potential applications. However, few studies on the flow fields in the mini‐bubble column can be found at present. In this work, particle image velocimetry (PIV) was used to visually study the velocity fields, vorticity fields and bubble dynamics in the gas–liquid mini‐bubble columns with column inner diameters of 1–3 mm and mini‐bubble diameters ranged from 0.7 to 1.3 mm. It is found that with the increase of superficial liquid velocity, bubbles rose from almost straight line to Z‐shaped or S‐shaped trajectory, and the bubble trajectory changed from one‐dimension to three‐dimension; when the bubble velocity changed, the bubble size and gas holdup decreased; bubble terminal velocity was controlled by bubble buoyancy and flow resistance, and increased slightly with bubble coalescence. These findings may provide basic reference for the design and scale‐up of such a mini‐bubble column reactor. [ABSTRACT FROM AUTHOR]

Purpose: Particle size control is of vital importance to the performance and manufacturability of a solid drug substance used in an oral dosage pharmaceutical product. Numerous options for control are available to engineers and scientists engaged in process design; this study seeks to demonstrate the steps taken to define the optimal solution. Method: Wet milling, terminal size control though crystallisation alone and dry milling were studied as potential methods of particle size control. Laboratory experiments were conducted for each of these options. Long-term manufacturing cost implications were estimated, while a qualitative analysis of factors such as regulatory burden was conducted. Results: Each control option was shown to produce an active pharmaceutical ingredient (API) of sufficient quality via a robust and scalable process. Differences emerged when each method was subjected to a broader analysis of supporting factors (regulatory, cost, supply chain). Conclusion: In this case, wet milling was selected as the most cost-effective option for control with the lowest expected regulatory burden. Regardless of the method chosen for this particular case, the framework should have broad applicability to different APIs. [ABSTRACT FROM AUTHOR]

The properties of particle ensembles are defined by a complex multidimensional parameter space, namely particle size, shape, surface, structure, composition and their distributions. Macroscopic product properties are a direct result of these disperse particle properties. Therefore, the comprehensive multidimensional characterization of particle ensembles is a key task in any product design. However, the determination of complex property distributions is major challenge. We provide a broad overview of the current tools for multidimensional particle characterization. First, the mathematical handling of multidimensional (nD) property distribution is outlined as a necessary framework for the correct handling of nD particle size distributions (PSDs). Then, well-established techniques as well as recent developments with the potential to extract nD property distributions are reviewed. Ex situ imaging techniques like electron tomography or Raman spectroscopy with AFM co-localization, for instance, provide a resolution on the level of single particles but are limited in terms of sample statistics. A particular focus lies therefore on methods in the gas and the liquid phase, which provide multidimensional particle properties either directly or by a combination of one-dimensional techniques.

Integration of physics principles with data-driven methods has attracted great attention in recent few years. In this study, a physics-informed dynamic mode decomposition (piDMD) method, where the mass conservation law is integrated with a purely data-driven DMD method, is developed for fast prediction of the spatiotemporal dynamics of solid volume fraction distribution in bubbling fluidized beds. Assessment of the prediction ability using both piDMD and DMD is performed using the CFD-DEM results as the benchmark: Both DMD and piDMD can predict the short-term behaviour of solid volume fraction reasonably well, but piDMD outperforms the DMD in both qualitative and quantitative comparisons; With respect to their long-term ability, the piDMD-based prediction of the instantaneous solid volume fraction distributions is qualitatively correct although the accuracy needs to be improved, and the predicted time-averaged radial and axial profiles are satisfactory; Whereas the DMD-based prediction of instantaneous snapshots and time-averaged results is completely nonphysical. Present study provides a fast and relatively accurate method for predicting the hydrodynamics of gas-solid flows. • Physical principle is integrated with data-driven method. • A physics-informed dynamic mode decomposition (piDMD) is proposed. • piDMD enables the long-term prediction of solid volume fractions. • piDMD outperforms purely data-driven DMD. [ABSTRACT FROM AUTHOR]

Solar and other renewable energy driven gas-solid thermochemical energy storage (TCES) technology is a promising solution for the next generation energy storage systems due to its high operating temperature, efficient energy conversion, ultra-long storage duration, and potential high energy density. Experimental and theoretical studies suggest that the respective gravimetric and volumetric TCES energy storage densities vary from 200 to 3000 kJ kg−1 and 1–3 GJ m−3. Solar radiation or heat generated from electric furnaces powered by renewable electricity can be stored in the form of chemical energy through endothermic reactions, while the stored chemical energy can be converted to thermal energy via an exothermic reaction when needed. The design of highly effective reactors requires a deep understanding of materials, thermodynamics, chemical kinetics, and transport phenomena. At time of writing, TCES reactors are yet to be deployed at commercially relevant scales, leaving a substantial gap between development efforts and commercial feasibility. Therefore, this review aims to examine the state-of-the-art design and performance of particle-based TCES reactors with different reactive materials. Fundamentals related to TCES reactive materials, reaction conditions, thermodynamics and kinetics, and transport phenomena are reviewed in detail to provide a comprehensive understanding of the reactor design and operation. Five major types of TCES reactors have been comprehensively reviewed and compared, including fixed, moving, rotary, fluidized, and entrained bed reactors. Most reported prototype reactors in the literature operate at lab scale with thermal inputs below 40 kW, and scaled TCES reactors (e.g., at megawatt level) are yet to be demonstrated. The nominal reactor operating temperatures range from 300 to 1500 °C, depending on the selected chemistry, reactive material, and heat sources. To evaluate their designs, the reactors are assessed in aspects of performance, cost, and durability. Discrepancies in performance indicators of energy storage density, extent of reaction, and various energy efficiencies are highlighted. The scale-up of reactors and power block integration, which hold the key to the successful commercialization of TCES systems, are critically analyzed. Advanced materials (both reactive materials and ceramic reactor housing materials), effective particle flow control, advanced modeling tools, and novel system design may bring significant improvement to the energy efficiency, storage density and cost competitiveness of particle-based TCES reactors. [ABSTRACT FROM AUTHOR]

Battery materials, pharmaceuticals, solar cells, coffee powder, 3D printed components, etc., all these products have in common that they are predominantly made of particles. Ensuring high product quality with optimal raw material and energy utilization is only possible with extensive and many years of experience in the operation of such processes. This unsatisfactory situation is due to the complexity of particulate products, which still hinders extensive automation and autonomous process control. The challenge is to couple the respective basic operations with characterization devices, process dynamics and modern control algorithms to form a closed loop for process control. As a result, some day it should be possible to set the desired property profiles of particulate products with the most energy‐ and raw material‐efficient operation possible with a "push of a button". [ABSTRACT FROM AUTHOR]

Wet granulation process is a major unit operation in production of pharmaceuticals as solid dosage oral formulation. Indeed, granulation is used to improve the formulation properties such as flowability, compressibility, and so on for pharmaceutical manufacturing. Different types of granulations can be used in pharmaceutical manufacturing in which the selection of proper process depends on the operational conditions as well as formulation properties. In current decades, twin-screw wet granulation has been of paramount interest owing to its superior properties. Pharmaceutical manufacturing industry are trying to move towards continuous mode by which the efficiency can be improved compared to the batch mode. Therefore, development of continuous granulation process is of great importance. In this review article, various processing units applicable for wet granulation of pharmaceutical formulations for solid dosage forms are reviewed and discussed. The advantages and disadvantages of the processes are discussed and listed along with modeling approaches for simulation of process. The governing models and numerical schemes applicable for design of wet granulation are also critically discussed. The main focus is on wet granulation as this method has attracted much attention in pharmaceutical processing.

In this study, the techno-economic performance of supercritical carbon dioxide (sCO 2) power cycles in concentrating solar power plants based on particle technology is assessed. A simplified levelized cost of electricity calculation was used to investigate the effect of cycle parameters, compare cycle layouts and allow for comparing optimized sCO 2 power blocks with steam technology. Results showed that simple cycle layouts with fewer components and lower cycle parameters lead to the lowest energy cost. This is caused by (a) fewer components, (b) lower primary heat exchanger, turbine as well as recuperator cost if the turbine inlet temperatures is limited and (c) a lower cost of the thermal storage system if the sCO 2 temperature increase in the primary heat exchanger is large. Nevertheless, even the most economical sCO 2 variants generate electricity at a 10 % higher cost than a steam reference system and a significantly lower efficiency. These results held true when changes were made to cost models. Finally, it was shown that the cost of main sCO 2 equipment would have to be reduced by 30 %–50 % to reach cost parity with steam systems. These findings will need to be confirmed with more detailed off-design simulations and optimized solar field components. • CSP plants with sCO 2 cycles have a higher levelized cost than those with steam cycles. • Costs of sCO 2 main components need to be lowered by at least 30 %. • Simple, low-effciency cycles are more cost effective for CSP plants with sCO 2 cycle. • Indirect sCO 2 power block costs are commonly underestimated in literature. [ABSTRACT FROM AUTHOR]

The properties of particle ensembles are defined by a complex multidimensional parameter space, namely particle size, shape, surface, structure, composition and their distributions. Macroscopic product properties are a direct result of these disperse particle properties. Therefore, the comprehensive multidimensional characterization of particle ensembles is a key task in any product design. However, the determination of complex property distributions is major challenge. We provide a broad overview of the current tools for multidimensional particle characterization. First, the mathematical handling of multidimensional (nD) property distribution is outlined as a necessary framework for the correct handling of nD particle size distributions (PSDs). Then, well-established techniques as well as recent developments with the potential to extract nD property distributions are reviewed. Exsitu imaging techniques like electron tomography or Raman spectroscopy with AFM co-localization, for instance, provide a resolution on the level of single particles but are limited in terms of sample statistics. A particular focus lies therefore on methods in the gas and the liquid phase, which provide multidimensional particle properties either directly or by a combination of one-dimensional techniques. [ABSTRACT FROM AUTHOR]

Much confusion exists on whether force‐ or energy‐based descriptions of cohesive‐particle interactions are more appropriate. We hypothesize a force‐based description is appropriate when enduring‐contacts dominate and an energy‐based description when contacts are brief in nature. Specifically, momentum is transferred through force‐chains when enduring‐contacts dominate and particles need to overcome a cohesive force to induce relative motion, whereas particles experiencing brief contacts transfer momentum through collisions and must overcome cohesion‐enhanced energy losses to avoid agglomeration. This hypothesis is tested via an attempt to collapse the dimensionless, dependent variable characterizing a given system against two dimensionless numbers: A generalized bond number, BoG–ratio of maximum cohesive force to the force driving flow, and a new Agglomerate number, Ag–ratio of critical cohesive energy to the granular energy. A gamut of experimental and simulation systems (fluidized bed, hopper, etc.), and cohesion sources (van der Waals, humidity, etc.), are considered. For enduring‐contact systems, collapse occurs with BoG but not Ag, and vice versa for brief‐contact systems, thereby providing support for the hypothesis. An apparent discrepancy with past work is resolved, and new insight into Geldart's classification is gleaned. [ABSTRACT FROM AUTHOR]

Geometry‐dependency and plasticity are considered in the contact force models for the discrete element method simulations of elastic and elastoplastic fiber assemblies subject to uniaxial compression. It is observed that the contact force models have a significant impact on compressive loads. A simplified normal contact force model leads to smaller loads at large solid volume fractions compared to the experimental results, while the present geometry‐dependent models give better predictions. Simulations with a simple Coulombic tangential contact force model (considering sliding friction only) significantly underestimate the loads, while a Mindlin tangential force model that considers static friction improves the predictions. For the modeling of the fibers that undergo large plastic deformations, plasticity should be considered for both the fiber bending and fiber–fiber normal contact in order to obtain correct simulation results. Elastic models for fiber–fiber contact and fiber bending deformation remarkably overpredict the loads for the plastic fibers. [ABSTRACT FROM AUTHOR]

Particle filtration is a major building block in effluent treatment facilities for water reuse in agriculture, industry, and the community. Yet, its incorporation in modern hybrid treatment systems still lacks basic know-how for process optimization. This paper aims to provide a profound understanding of particle filtration vis-à-vis its various reuse applications. The methodology used follows a road map depicted as a growing tree, representing the author’s research from roots to top: roots—basic modeling, mechanisms; tree trunk—filter design approach for reuse; branches—enhanced particle removal; and tree crown—pretreatment, bioparticle, and nanoparticle removal. Contact deep-bed filtration process optimization, algorithms for economically optimal filter design, tertiary filtration and membrane pretreatment, and related energy issues are being discussed. Some of the conclusions are that pilot plant planning should be primarily derived from particle surface interactions with filter media, based on measurements of mineral particle or bioparticle size, shape, and physicochemical characteristics, and applying attachment-detachment models. Filter design optimization would comprise of selecting efficient water quality processes first, followed by economic optimization for final design parameters. A holistic approach in the design of filtration facilities, standing alone or incorporated in hybrid systems, is also considered.

[Display omitted] • Oil shale residues are transformed into mullite-rich materials at high temperatures. • Mullite formation is optimally achieved at about 1300 °C in 5 min. • Al 2 O 3 supplement to oil shale residues is needed to convert excess SiO 2 to mullite. • Aluminum ash is a source of Al 2 O 3 but needs pre-treatment to remove inhibitory NaCl. • NaCl in aluminum ash hinders mullite formation with unexplainable mechanisms. Oil shale residues, a solid waste produced during oil shale mining, extraction, and refining processes, pose a significant challenge to the environment and sustainability. This study aims to develop a thermochemical conversion process to transform oil shale residues into valuable composite materials. Experiments are conducted to investigate the effects of reaction temperature, time, and reactant composition on the reaction behavior and resulting product characteristics. The results demonstrate that mullite-rich composite materials can be prepared at reaction temperatures of around 1300 °C with reaction times of 5 min. Industrial aluminum ash can be used to supplement the aluminum needed for the complete conversion of excess SiO 2 in oil shale residue, but it must be thermally treated to eliminate the NaCl content, which hinders mullite formation. Overall, this study offers a viable approach to converting solid waste into valuable resources while simultaneously addressing the environmental concerns associated with oil shale residues. [ABSTRACT FROM AUTHOR]

A new component of the combined finite-discrete element method (FDEM) is employed to estimate the effects of geometrical features, friction and energy dissipation parameters on the bulk properties of rigid pellet packs. This work constitutes the first systematic validation of the Solidity FDEM code for rigid particles. The experimental and numerical axial and radial packing density profiles and orientation distributions have been compared, confirming that the numerical simulations of packing of cylindrical catalyst supports, glass beads and trilobe pellets deposited in a cylindrical container match the corresponding emergent bulk properties obtained from X-Ray CT scans. The presented results are a first confirmation of the applicability of FDEM based methods to the simulation of this class of multi-body problems. The assessment of the accuracy of the simulated topology of the pellet pack that is established in this work is encouraging for further investigations of the multi-physical engineering systems of interest for catalyst pellets involving hydro-thermo-mechanical, fracturing and fragmentation interactions using coupled FDEM formulations. Unlabelled Image • A combined finite-discrete element method (FDEM) is used in packing simulations. • The mesh, contact, friction, damping parameters influence on packs is shown. • FDEM packs of cylinders, beads, trilobes match X-Ray scans emergent properties. [ABSTRACT FROM AUTHOR]

This research evaluated the treatment and processing of white shrimp (Litopenaeus vannamei) exoskeleton by studying the physicochemical characteristics of the biomaterial viewing evaluate its adequacy as a sorbent. White shrimp shell contains chitin, a biopolymer with sorbent properties, and calcium carbonate, an acidity neutralizing agent, among its principal constituents. The exoskeletons, excluding the head, were treated by proposed low-cost methodology. Elemental chemical characterization was performed by inductively coupled plasma mass spectrometry, identifying two different constituent groups: trace and macro elements. Thermogravimetric analysis indicated a high thermal stability when compared to commercial chitin. The Surface Area and Pore Size and Volume analyses showed a heterogeneous specific surface area, with a mean pore diameter in the range of microporous (ϕ < 20 Å) and mesoporous (20 Å < ϕ < 500 Å) predominantly. The particle size, determined by Mastersizer 2000, and the morphology, determined by scanning electron microscopy and energy dispersion X-ray spectroscopy, confirmed the heterogeneity of the processed bioresidue. This characterization indicated the adequacy of the treatment for obtaining from shrimp shells a chitinous biomaterial for potential use as a sorption and neutralization agent once its main constituents (chitin and calcium carbonate) were not modified with the treatment. [ABSTRACT FROM AUTHOR]

The accuracy of coarse‐grained discrete element method (CGDEM) relies on appropriate scaling rules for contact and fluid‐particle interaction forces. For fluidized bed applications, different scaling rules are used and compared with DEM results. The results indicated that in terms of averaged values as mean particle position and voidage profile, the coupling of computational fluid dynamics and CGDEM leads to accurate results for low scaling factors. Regarding the particle dynamics, the approach leads to an underestimation of RMS values of particle position indicating a loss of particle dynamics in the system due to coarse graining. The impact of cell cluster size on drag force calculation is studied. The use of energy minimization multiscale drag correction is investigated, and a reduced mesh dependency and good accuracy are observed. [ABSTRACT FROM AUTHOR]

• Mean mass flux (Q m) shows an increase with decreasing L/D of the pipe. • Mean mass flux (Q m) saturates beyond D/D p of 15. • Poisson ratio has negligible while inclination has significant effect on flux. • In pendular regime, moisture increase causes a decline in the mass flux. • At higher Bond numbers, cohesion dominates resulting in decrease of mass flux. Flow of granular material through a pipe has several industrial applications but maintaining a uniform mass flux is quite challenging. In this work, monodisperse granular flow (non-turbulent and non-dense phase particle transport) through a vertical pipe was simulated using discrete element method (DEM). Effects of different geometric and granular parameters on mass flux of cohesive and non-cohesive solids were analyzed and evaluated. Several important parameters and their effects on mass flux were studied like: L/D ratio, pipe diameter to particle diameter ratio (D/D p), Poisson ratio, and pipe inclination angle. Furthermore, effects of moisture content and Bond number on mass flux were also investigated. These parameters influenced mass flux except Poisson ratio which showed no significant improvement in mass flux upon increasing the value of this ratio. [ABSTRACT FROM AUTHOR]

A binary mixture is mixed in a rotating drum composed by 19 rings with different inner diameters. It is found that the larger particles are concentrated in the rings with smaller inner diameters. The collection of the larger particles in these rings is due to the particle dynamic angle of repose. The transition from the particle segregation core pattern at the end wall to the good radial mixing rings is through a transient turning comet segregation pattern. This transition is closely related to the distance from the ring with the smallest inner diameter to the ring with the largest inner diameter. Having a higher fraction of larger particles in a ring requires both the collection ring having a smaller inner diameter and a smoother inner diameter transition to the neighboring rings. [ABSTRACT FROM AUTHOR]

Agitated drying of pharmaceuticals remains a challenging manufacturing step due to the simultaneous heat transfer, mass transfer, and physicochemical changes occurring during the process. This work focuses on the heat transfer component by implementing the discrete element method to model dry particles in a heated bladed mixer. Simulations varying material conductivities and impeller agitation rates were conducted to evaluate the influence on the mean bed temperature and distribution.The results indicated that increasing the agitation rate generally improved heat trans-fer up until a critical agitation rate where the rate of heat transfer plateaued. The magnitude of this improvement in heat transfer depended on the material's thermal properties. We observed three regimes: a conduction-dominated regime where particles heated quickly but with an annular temperature gradient, a granular convection-dominated regime where particles heated slowly but uniformly, and an intermediate regime. The results were nondimensionalized to enable predictions and help inform drying protocols. [ABSTRACT FROM AUTHOR]

• A brief review on XCT in the field of powder technology is given. • Selected examples show the application of XCT in process engineering. • Future applications of XCT in process engineering are discussed. X-ray computed tomography (XCT) has seen significant development in scan time and spatial resolution over the last decades. It is now increasingly used in the field of particle technology including ex-situ and in-situ applications to study time-lapse processes. This is due to its non-destructive principle giving 3D information on the inner structure and composition of specimens. This article shortly summarizes the field of XCT focusing on terms relevant for particle technology. It also gives a brief outlook on promising directions of development, which may significantly improve XCT. Using different examples from bulk solids handling, flow in porous structures and filtration, the monitoring of concentration differences and the fracture of particles, the application of XCT in particle technology is shown and its perspective is discussed. [ABSTRACT FROM AUTHOR]

The circulating-turbulent fluidized bed (CTFB) is an important fluidization regime that can maintain a high solid concentration and high reaction intensity as in turbulent fluidized bed, and suppress solids back-mixing as in circulating fluidized bed. Computational fluid dynamics (CFD) studies on it are however very sparse. In this study, extensive three-dimensional CFD simulations of CTFB are carried out using the mesoscience-based structural model (Liu et al., 2023), where the gas-rich dilute phase and the particle-rich dense phase are defined as the two interpenetrating continua, instead of treating the gas and particles as the two interpenetrating continua as in classical two-fluid models. It is shown that the model is able to faithfully predict the hydrodynamics of CTFB, in terms of axial and radial solid concentration profiles and radial solid velocity profiles. This study not only provides a systematical CFD study on the hydrodynamics of gas–solid flow in CTFB but also offers validations of the mesoscience-based structural model via simulating the hydrodynamics of new fluidization regime (CTFB). [Display omitted] • CFD simulation of circulating-turbulent fluidized beds was performed. • Gas-rich dilute phase and particle-rich dense phase are defined as interpenetrating continua. • Mesoscience-based structural model was validated. [ABSTRACT FROM AUTHOR]

Near-infrared spectroscopy (NIRS) is nowadays an established analytical technique in the pharmaceutical industry. The aim of this review is to present the progress of NIRS in providing useful information for pharmaceutical particle technology. NIR methods are now developed to characterize a wide variety of materials (active pharmaceutical ingredients, excipients, co-processed powders, and physical mixtures) and pharmaceutical dosage forms (conventional, modified drug release technologies, and phytomedicines). This review also provides a number of spectra to illustrate the fundamental understanding of NIRS which has been gained. The sampling that must occur prior to the acquisition of near-infrared spectra is also discussed, as well as developments in monitoring mixing, tableting, and coating. This review will be valuable for product formulation and process engineering specialists. [ABSTRACT FROM AUTHOR]

This paper presents an experimental examination of the velocity field distribution in the separation chamber of a uniflow cyclone with closed particle outlet to evaluate the swirl characteristics in the vortex finder region based on stereoscopic particle image velocimetry. A cold flow model with a closed particle outlet was used to assess different angles of attack and core size ratios at typical Reynolds numbers for the separation of low loaded gas‐solid flows. The focus of the study was on the relationship between swirl strength as well as performance data. At higher angles, the parabolic swirl strength distribution changed to a region with constant high acceleration of the particles in the separation zone. Integral and differential swirl numbers were correlated with the ratio of tangential to radial velocity and to the calculated cut size diameter. At low angles of attack, implying a strong redirection of flow perpendicular toward the main flow direction and small core size ratios, defined by the radial distance between hub and tip, the local differential swirl number can be more than twice as large as in the base configuration. Yet, the integral swirl number hardly changed. The velocity fields showed mean tangential to radial velocity ratios ranging from 0.73 to 6.85 at swirl vane angles of 15°–60°; core size ratios between 0.125 and 0.625 at vortex finder diameter were measured and calculated cut size diameters between 10 and 90 μm were derived. This data provides the foundation for further validation studies and the development of new design criteria. © 2018 American Institute of Chemical Engineers AIChE J, 65: 766–776, 2019 [ABSTRACT FROM AUTHOR]

Measurements of particle dynamics of neutrally buoyant suspensions of non‐Brownian glass beads in a Couette cell using dynamic sound scattering are reported. The dynamics were studied under steady shear flow across the entire gap between the stator and rotor for shear rates from 0.26 to 6.59 s−1 and particle concentrations from 20% to 50%, thereby enabling a comprehensive investigation of the dynamics to be carried out. The average particle velocity profile varies linearly with depth inside the cell for all shear rates and concentrations. The fluctuations in the particle velocities are large, indicating that the particles are not confined to streamlines but continue to fluctuate substantially during steady flow. Our data indicate that the fluctuations are anisotropic. The components of the velocity fluctuations (granular temperature) parallel to the flow and in the vertical direction are much larger than in the radial direction. The fluctuation anisotropy decreases as the concentration increases. © 2018 American Institute of Chemical Engineers AIChE J, 65: 840–849, 2019 [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Conductive contact modeled when gap between computational elements must be maintained. • Volumetric energy sources simulate thermal exchange at flagged contacting elements. • Method proves to be robust for range of contact resistances and thermal properties. • Excellent agreement with standard finite volume solution with contacting elements. • Facilitates study of thermal contact in dynamic, resolved particle flow/fixed mesh topology. Abstract Traditional computational fluid dynamics (CFD) simulations with resolved objects progressing through the fluid using a moving and deforming mesh require a fixed mesh topology. Though such simulations may more readily capture conditions where large gradients in the flow field exist, particularly high speed, compressible flow phenomena, the ability to directly model the conduction portion of the contact between particles or between particles and other solid bodies immersed in the fluid is thus restricted. A new method was devised to allow for the maintenance of the mesh topology while simulating the contact heat conduction between a discretized particle pair and between a discretized particle and a wall for the intended purpose of implementation of the technique within a computational fluid dynamics (CFD) based coupled particle–fluid flow model. The method is tested for a range of contact resistances (0–1 × 10−3 m2 K/W) and material thermal conductivity (1.60–162 W/m K) and specific heat (50.28–5028 J/kg-K) combinations with one object initially at 700 K and the other at 300 K. The temperature distributions across the mid-particle or mid-particle and wall line produced by the new method at a given time are compared to the results for a standard finite volume simulation of contacting bodies. The maximum difference in the local temperatures obtained is under 1%. Hence, the technique is a robust means of simulating the resolved heat conduction contact thermal energy exchange without connected computational elements, retaining the needed fluid gap space around the solid bodies. Future work will build upon this technique to include the convective and radiative modes of heat transfer before simulating moving and interacting particles in a fluid flow. [ABSTRACT FROM AUTHOR]

The rotary kiln is an essential device in chemical and metallurgical industries, with applications in a wide range of solids manufacturing processes. In particular, in the preparation of industrial chemical catalysts, the kiln has become a popular reactor for continuous calcination of catalysts ranging from millimeter-sized extrudates to micron-sized powders. As granular and powder flow behaviors are difficult to characterize, the design and scale-up of rotary calcination processes are often performed empirically. The goal of this research is to improve the fundamental understanding of powder flow in rotary kilns to aid in optimization of the continuous calcination process. For successful calcination to occur, the residence time of the particles must exceed the time required for heating and subsequent treatment. For uniform treatment of the feed, the particles must also exhibit low axial dispersion. In this work, the mean residence time and axial dispersion coefficient for a cohesive fluid catalytic cracking powder were determined in a pilot plant kiln by measuring the residence time distribution. This study utilized a pulse test developed by Danckwerts. Results were fit to the Taylor solution of the axial dispersion model and compared to the Sullivan prediction for mean residence time. It was found that the mean residence time decreases as the feed rate, kiln incline, and rotation rate increase. It was also found that the axial dispersion coefficient increases with speed of rotation and angle of incline. However, the axial dispersion coefficient decreases as the feed rate is increased. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Aggregates show self-assembling due to the ordering of the internal structure. • A characteristic time-scale of equilibration inside a drying droplet exists. • A decrease of drying time results in more disordered aggregates. • Particle diffusion in the droplet determines the final structure of the aggregate. Abstract Formation of structurized micro/nanoparticle aggregates in spray drying process is analyzed theoretically and experimentally. Colloids of mono- and bimodal particle size distribution are used as the precursors to demonstrate different patterns of particle self-organization inside the drying droplet. In case of monodisperse primary particles their self-organization in the final aggregate results in either a hollow or a full (packed) spherical structure. For primary particles with bimodal size distribution, either the layered structure of aggregates is formed (with smaller particles forming outer layer and the bigger particles captured inside) or the ordering of bigger particles on the aggregate surface is observed, depending on process parameters. Numerical investigations allow to predict and explain the conditions at which self-assembling of particles within powder aggregates takes place. [ABSTRACT FROM AUTHOR]