Mechanisms governing the gasification to combustion regime transition in counter-current packed bed biomass systems are investigated in the current work. Single-particle experiments are performed with different oxidizer streams (air, mixtures of O2/CO2) to bring out the role of the extinction of the envelope non-premixed “volatiles” flame and simultaneous volatile-char combustion at the stagnation

The effect of alternating magnetic field on the pressure drop inside a fixed bed with different types of packing is experimentally investigated. The bed was packed with three different masses of iron(III)oxide powder as a loosely packed, tightly packed and an over tightly packed bed system. A Helmholtz coil was used to apply an AC magnetic field (60 Hz) and the pressure drop measurements were made

Separation and characterization studies were carried out on end-of-life mobile printed circuit boards (EoL Mobile PCBs). The raw material has been subjected to a hammer mill to reduce the particle size. A series of comminution experiments were conducted to produce different size particles, which indicates that a number of crushing stages are needed to generate finer products. Comminution products consist

Transmission Electron Microscope (TEM) image processing is implemented in the spatial distribution analysis of iron-platinum based nanoparticles, drop-casting on diethylene glycol (DEG). Before the redispersion in hexane with surfactant additions, these magnetic particles aggregate in the nanosuspension after a prolonged storage. The precise analysis of aggregations by conventional methods is not possible

The main purpose of this study is to obtain the biogenic silica nanoparticles from selected types of plants and thorough characterization. Plants create SiO2 nanoparticles while growing from the colloidal solution of orthosilicic acid contained in the soil. Together with acid, they absorb additional ions that are essential for their growth, which was found using SEM and EDX analysis. The organic part

The aim of this work is to demonstrate the possibility of using electric field forces for the recovery of copper from a fine PVC/Cu granular mixture of low metal content (less than 15%), obtained as “PVC fraction” in the recycling process of electric cable waste from automotive industry, using vibrating table technology. Electrostatic separation of copper granules which are “impurities” in the PVC

This work deals with the creation of a mathematical model which will predict with sufficient accuracy the size of granules in the high-shear granulation process. The aim of the paper was to create a model created with dimensionless criteria to give the size of granules as a function of selected process parameters, equipment, and experimental material. Microcrystalline cellulose granules were manufactured

Developed fractures are important storage space and permeable channel in hydrocarbon reservoirs. However, they will lead to drill-in fluid loss and induce severe formation damage. Fracture plugging with granular lost circulation material (LCM) is most commonly used to control drill-in fluid loss. To our best knowledge, traditional research about LCM bridging mainly performed by the trial-and-error

Developing a facile and green approach to synthesize gold nanoparticles (AuNPs) with high catalytic activities for the reduction of toxic nitrophenols to beneficial aminophenols is of tremendous environmental and industrial relevance. The present study reports an environmentally benign synthesis of AuNPs using aqueous extract of seaweed Lobophora variegata as a potential bioreductant. The signatory

The linear-slider-dashpot (LSD) soft sphere model is used extensively to model particle collisions in dense particle systems. The contact mechanics in the normal and tangential directions are modeled by a spring, damper, and dashpot system. The current work evaluates different existing tangential direction implementations of the LSD model. The existing models require storing the cumulative tangential

This study reports the effect of La2O3 addition on the microstructural and some mechanical properties of the W-Ni-WB composites. Composites having the compositions of W – 1 wt% Ni – 2 wt% WB and W – 1 wt% Ni – 2 wt% WB – x wt% La2O3 (x = 0.5 and 1) were fabricated by mechanical alloying (MA) and activated sintering methods. Phase and microstructural characterizations of the mechanical alloyed powders

Nonionic nano-micro latex was prepared via emulsion polymerization with styrene (St), butyl acrylate (BA) and polyethylene methyl ether methacrylate (MAPEME). The structure of latex was characterized by Fourier transform infrared spectroscopy (FTIR). Particle size tester was employed to detect the size distribution and 20% volume of latex was attributed to nano-scale. Gel permeation chromatography

The polydopamine modified with magnetic nanoparticles (Fe3O4@PDA) was prepared and used for Pb2+ removal from aqueous liquids. The resulted Fe3O4@PDA nanocomposite was characterized with Fourier transform infrared spectra (FTIR), vibrating sample magnetometer (VSM), transmission electron microscope (TEM) and X-ray diffraction (XRD). The optimized Pb2+ ions adsorption process was studied by response

Due to the serious environmental problem, dry coal separation has become the hot research topic in the world. In the study, an air dense fluidized bed was used for reduction of ash content and mercury rejection with shallow bed heights. The results showed that pressure drop fluctuation was smallest when bed height was 100 mm. When fluidized gas velocity was 1.50 Umf, the ash content decreased to 9

In-depth water flooding profile modification is a new problem for low permeability formation under fracturing. Profile control study for in-depth cross flow which couples fracture and matrix is neither comprehensive nor complete at present. Artificial hydraulic fracturing core is manufactured to conduct core flood experiment. In-depth profile modification mechanisms of gel-nitrogen-foam are revealed

In this study, a coupling rule based on Lattice Boltzmann Method (LBM), Immersed Boundary Method (IBM), and Discrete Element Method (DEM) was developed to simulate settling of particles in Newtonian liquid. The direct forcing IB-LBM, which was enhanced by the split-forcing technique, was utilized to account for fluid/solid interactions. Dynamic behavior of particles during collisions was evaluated

The Discrete Element Method (DEM) is used to simulate the mixing and discharging processes of binary particles in a laboratory truck mixer. The contact parameters in the DEM model are calibrated by experiments and then used to simulate the particle mixing and discharging processes in truck mixer under seven groups of operation parameters. Numerical results show good agreements with the experimental

An Eulerian–Eulerian model coupled with a population balance model (PBM) is adopted to investigate the growth process of polysilicon particles in a polysilicon fluidized bed reactor. A novel particle growth model, considering the effect of interphase velocity difference, is proposed and incorporated into PBM. The interphase mass transfer rate and particle growth rate are obtained based on the modified

The urea-nitrate combustion and homogeneous precipitation methods have been comparatively examined for the preparation of CuO/CeO2/ZrO2/Al2O3 catalysts. Their physicochemical properties, as well as their hydrogen production ability via the steam reforming of methanol, have been studied. Prepared catalysts were characterized using XRD, FESEM, EDX, BET, and FTIR analyses. Characterization analyses and

Coal preparation plants commonly use density-based separators to remove high-density inorganic matter (rock) from low-density carbonaceous matter (coal). Liquid–solid fluidized bed separators (FBS), segregates particles with different size, shape, and density. Particles with different terminal velocities report to various heights of the fluidization column. This property has been used to beneficiate

The basic objective of research work was to develop, optimize and evaluate MBZ loaded NLCs to overcome the issues of poor solubility and bioavailability of the drug. The nanoformulation was prepared by melt-emulsification ultrasonication technique and optimizes the formulation parameters by Box–Behnken design. The optimized MBZ loaded NLCs were evaluated for its particle size, drug content and encapsulation

NiCuZn ferrite nanoparticles having the chemical composition Ni0.5Cu0.1Zn0.4Fe2O4 were synthesized by the microwave direct denitration (MDD) method from a mixture of metal nitrate hydrate solutions. A single-phase of NiCuZn ferrite powder with an average particle diameter of about 30 nm could be obtained using this method at reaction temperatures higher than 900 °C. This diameter was less than one-fifth

Chitosan synthesized from the Pessu river crab shell was screened to coarse (CC, 600 µm), medium (MC, 300 µm) and fine (FC, 150 µm) aggregate for phenol removal. The aggregates were characterized for surface chemistry, surface morphology, thermal behavior, and surface texture. The surface chemistry showed the characteristics primary and secondary amine/amide groups of chitosan. The values of specific

Cold flow hydrodynamic study of a full loop, three-dimensional internally circulating dual fluidized bed (ICDFB) for coal gasification has been carried out using a Eulerian–Eulerian approach. The ICDFB system consists of a central riser and an annular bubbling fluidized bed (BFB) placed concentrically and interconnected by a solids separator and a loop seal. The compact design and simple geometric

Links between flow properties and formulation of powders of 100 and 500 µm mean particle sizes were investigated. To determine the influence of surface treatment, the flow properties of glass beads were analyzed after various surface treatments leading to hydrophilic, hydrophobic, and lactose-coated surfaces. Furthermore, to investigate the influence of powder core composition, agglomerated lactose

(2020). Correction. Particulate Science and Technology. Ahead of Print.

Magnetic separation, dense media suspension fluidization techniques are tested for dry beneficiation of iron ore fines presently and found to have limitations. In the present study, the potential of shallow bed air fluidized separator (SBAFS), which does not have any suspension media and has high throughput is investigated for iron ore fines beneficiation. A set of experiments was designed by response

In most tropical countries where sugarcane is grown at a commercial scale, there are substantial quantities of sugarcane bagasse ash rich in amorphous silica. A simple, low-cost chemical method for the extraction of pure silica from the boiler collected ash is of importance. In this study, sol–gel coupled with adsorption using activated carbon was used to extract high-purity amorphous silica from sugarcane

Magnesium/Teflon/Viton or MTV based pyrotechnic composition has been the most preferred composition for decoy flares against conventional heat-seeking missiles for more than four decades. MTV flares of standard configurations are available globally but the details of their manufacturing process including compacting pressure and compressive strength of the flare pellets have not been explicitly defined

Packed beds with diverging geometry find applications in packed bed reactors and converging geometry are used in the ethanol fermentation process. Experimental studies are conducted on pressure drop characteristics of converging and diverging packed beds with spheres of same diameter, spheres of different diameters, cylindrical inserts and mixing of spherical and cylindrical particles. The packing

Silica aerogel shows great potential in the relevant high-temperature applications, such as furnaces, tubes, and bricks. The related studies on addressing its behaviors under high temperatures are critically needed. Through this study, the effects of heating rate on its high-temperature behaviors of silica aerogel granule with a size of 100 mesh were addressed experimentally, including density, pore

In this paper, the flow of fly ash in fluidized dense phase pneumatic conveying through a section of pipeline having uniform pipe diameter has been modeled and analyzed using Computational Fluid Dynamics (CFD). Besides considering a single solid phase with the mean particle diameter, several solid phases based on the particle size distribution (PSD) have been incorporated in the developed CFD model

Water production management from oil and gas fields is a big challenge for petroleum industry. Re-injection and disposal of produced water into subterranean formations/oil reservoirs is considered as an environmentally-friendly solution for managing massive water production in petroleum industry. Formation damage resulted from plugging by dispersed particles in the injected water is one of the main

In this study, some activated carbons were prepared from sawdust using NaOH as an impregnating agent, a full factorial plan 23 was adopted to optimize and determine the interaction effects of some preparation conditions: impregnation time, impregnation temperature, and impregnation ratio. Elimination efficiency toward Erythrosine and Methylene blue in single and binary systems was selected as an optimization

Pneumatic conveying is one of the industrial processes that give the most electrical charge to divided solids. This electrical charge is generally a nuisance that can, for example, influence the flowability, create discharges or even explosions in the ducts. In order to counteract these tribocharging phenomena, which are not well apprehended, several authors designed and implemented different measurement

The novelty of incorporating carbon nanotubes (CNTs) in various matrices is becoming increasingly significant for the development of various composites to match the rising technological demands in industry. However, for the potentials of CNTs to be fully realized, the mandatory requirement to uniformly disperse them must be achieved. To effectively disperse these nanotubes in metallic matrices, ball

This paper results from an ongoing research into the modeling of losses due to bends in pneumatic conveying systems. An accurate estimation of pressure drop in bends is important for the reliable prediction of total pipeline pressure drop. Several existing bend pressure drop models have been discussed. Using appropriate particle-wall friction factor equation (based on straight pipe data) and the three

Mars atmospheric in-situ resource utilization processes will require dust filtration of large gaseous volumes. An electrostatic precipitator capable of operating in the Martian environment is under development to meet this need. We performed experimentation to aerosolize and inject Martian simulant particles with a representative dust density and size range into the precipitator intake and to measure

Abstract A CPFD hydrodynamic model was developed for a circulating fluidized bed system and the simulation results were validated against experimental data based on particle circulation rate. Sensitivity of the computational mesh was primarily tested and extended grid refinement was needed at the loopseal to match the particle circulation rate with experimental data. The particle circulation rate was

The nucleation of nanobubbles was studied through molecular dynamics (MD) simulations. The wettability and surface atomic-level structural features of the substrate were found to play a role in a ternary (solid, liquid, and gas) system that was composed of only simple Lennard-Jones fluids. The simulation first revealed that surface nanobubbles form only on a hydrophobic substrate, while for a hydrophilic

Sand production is a serious problem in exploring heavy oil wells and can cause sand well abandonment under severe conditions. Various sand control tools (e.g. slotted liner (SL) screens, wire-wrapped screens (WWSs), pre-packed screens, and premium screens) are recently developed. However, each sand control method has its drawbacks and limitations. Pre-packing gravel screens have not been improved

The present paper provides characteristics of three species of grain straw particles applied in the production of lignocellulose particleboards. For the sake of the investigation, rapeseed, rye, and triticale straw were fragmented to the size of particles used in the wood-based materials industry. The aim of the research was to determine physical properties of particle of rapeseed, rye, and triticale

The efficiency of grinding experiments is an important issue for many industries. In this paper, a central composite design-based methodology was proposed to investigate the four design factors that affect the particle sizes. The four design factors were specified as mill speed (% of Nc), ball filling ratio (fc), powder filling ratio (jb) and grinding time (min). Another important issue was how to

In this study, the erosion of the oval elbow duct pipe due to the natural gas–solid particles in the turbulent flow (k-epsilon) by (CFD) is investigated with specific consideration to the effect of the oval aspect ratio. The natural gas–solid particle turbulent flow is simulated by utilizing the two-way coupling, Eulerian–Lagrangian approach; while an enhanced wall treatment method is used because

In this study, the dominant intermolecular interactions at powder surfaces were investigated using inverse gas chromatography. Silica beads coated with molasses, corn starch, butter, or wheat gluten were used as model powders to emulate the interactions of surface components present in common food powders. The flow properties of the powders were analyzed using a rotational shear cell device at ambient

Nanoparticles (NPs) have great potential for a variety of applications in several industries including oil and gas industry. The addition of (NPs) to the drilling fluids may benefit the performance of drilling fluid properties. The production, use, and discharge of NPs have been raising concerns among the environmentalists as they have adverse effects on their ecology. Therefore, the oil and gas industry

Different crystallization times were studied during hydrothermally synthesis of ZSM-5 framework at moderate temperature to investigate the physicochemical properties and MTO catalytic behavior. The ZSM-5 samples were synthesized at moderate temperature (250 °C) and different crystallization times (24, 18, 12, 6, and 3 h). The synthesized samples were analyzed by XRD, FESEM, EDX, BET-BJH, FTIR, and

The morphological parameters of coarse aggregates, including the angularity, flat and elongated (FE) and particle size, strongly influence the performance of asphalt concrete. At present, the measurement of the angularity of coarse aggregate is affected by the particle size and the FE. To achieve independent characterization of angularity, the compression method is used to eliminate the influence of

In recent years, the eco-friendly synthesis of noble metal nanoparticles using bio-resources has given rise to a new trend in nanoscience and nanotechnology. In the present work, well-dispersed gold nanoparticles (AuNPs) are synthesized by redox of chloroauric acid (HAuCl4.H2O) using Silk Sericin (SS) obtained from Bombyx mori cocoons. The selection of SS, a textile industry waste, as a bio template

The pressure drop characteristics of negative pressure sampling drill pipe were studied experimentally in this work. The pressure drop was measured by a customized designed negative pressure sampling test system. The effects of the inner diameter of the drill pipe, the solid-gas rate and the inlet air velocity on the internal pressure drop of the drill pipe were analyzed. When the drill pipe is loaded

Three different tableted coffee mix formulations were produced: coffee mix tablet, effervescent coffee mix tablet, and effervescent coffee mix tablet added with lubricant (2 w/w% magnesium stearate). The frictional effects during the ejection of the formed tablets out from the die, the mechanical strength and the disintegration of the tablets were investigated. The coffee mix tablet displayed the highest

Sieving analyses are very susceptible to the unavoidable particle losses. Therefore, it is important to assess how sieving losses will affect the particle size distributions. This study aims to simulate sieving losses under a computing environment to further investigate their effects on the particle size distributions. For the purpose of this study, the cumulative size distributions of different particulate

Industrial bulk material transfer and handling processes often cause large amounts of dust emission and seriously threatens workers' health. Proper design of dust removal system requires an understanding of the volume flow rate of entrained air during the falling process of the particle plume. Based on previous researches, this paper deduces the formula of the volume flow rate of entrained air through

The present investigation describes the successful synthesis of mesoporous alumina (MeAl) nanoparticles for controlled drug delivery via a soft template route have been adopted using hexadecyltrimethyl ammonium bromide as template and aluminum chloride as precursor. The obtained Langmuir type II isotherm for MeAl showed P/Po 0.1 at 10 cm3/G STP. The Brunauer-Emmett-Teller study revealed the formation

This paper presents a review of particle breakage in granular soils by comprehensively summarizing the measurement of particle breakage, the fundamentals of particle breakage, the soil mechanics on particle breakage, the theoretical models of soil incorporating particle breakage. In the measurement of particle breakage, most particle breakage indexes were proposed according to the change of soil grading

Removal of material from the surface due to particle impact is typically referred to as erosive wear. Impact erosion involves many parameters and several wear mechanisms. In the present study, sandblast type erosion tester was used to investigate the influence of particle size, impact angle and exposure time in impact erosion. Air-borne dolomite particles were accelerated onto target specimens of mild

Crystal growth kinetics of succinic acid in an aqueous solution has been evaluated experimentally at the saturation temperature of 40 °C using a modified fluidized bed growth apparatus and isothermal seeded batch experiments. The measurements covered the supersaturation range between 0.01227 and 0.00713 kg/kg water and the crystal size ranges 560–630 µm, 400–450 µm, and 250–350 µm. A novel cone-shaped

Dry mineral separation methods are based on the pseudo-fluid properties of two-phase gas-solid fluidization during the air dense medium fluidized bed separation. In this paper, the air dense medium fluidized bed separation method was introduced for coal deashing. In order to better understand the impact of separation performance of air dense medium fluidized bed, the uniform stability of fluidized

Coking coal is extensively utilized in steel manufacturing industries for the preparation of coke because of their quality of leaving very less ash after burning. The effect of chemical additive, hydrated lime (for 0.05, 0.1, 0.5, 1, 1.5, and 2% of solids mass), in coking coal and water slurry (CCWS) are examined at the mass concentrations of 20 and 25%. Significant drop in shear stress is observed

For the reliable design of a pneumatic conveying system, accurate estimation of solids friction factor through horizontal straight pipe is of paramount interest. Although the “straight pipe” method is fundamentally more appropriate, the “back calculation” approach provides several practical advantages for testing and modeling. However, earlier literature reports that “back calculation” approach suffers