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High-shear granulation is widely used in many particulate industries for its good capability to improve the size, strength and composition uniformity of powder substances. This work conducted an experimental study to investigate the granulation behavior of iron ore fine in a horizontal high-shear granulator, such as granules size distribution, granules growth rate, and permeability of the granules bed. The results show that the granule size and permeability of packed granules bed increase gradually with increasing the granulation time, and the growth of granules can be divided into three stages: the rapid growth stage, the slow growth stage and the relatively stable stage. Both the higher rotational speed and larger number of impellers increase the kinetic energy and collision frequency of the particles, which causes the increase of average granule size, growth rate and permeability of granules packed bed. On the other hand, the shear damage effect of the impellers on the granules is also enhanced with the increase of rotational speed and impeller number, resulting in significant granule size segregation.

Current trends in the ceramic industry see an increasing interest on porcelain stoneware, by which is possible to produce large tiles and slabs. These products are manufactured by spray-dried powders, which have excellent technological properties but require high energy and water consumption. Dry-processed granulates allow to reduce such a consumption, but suffer from a different technological behavior. A solution to improve the environmental sustainability of ceramic tile-making is mixing powders prepared by the wet and the dry routes. The technological features of industrially manufactured mixed powders was investigated (rheological properties, compaction response and firing behavior) in order to point out advantages and possible pitfalls. Dry-processed and spray-dried granulates exhibit different distributions of size, shape and moisture that reflect on distinct rheological and compaction behaviors. Mixed powders show a more or less accentuated deviation from linearity between the end terms. This fact makes possible to add up to ∼50% dry granulates by keeping the technological properties close to current industrial bodies. Sparings of water, energy and CO2 emission for the milling and granulation stages are estimated for a mix 50% spray-dried and 50% dry-processed powders.

Graphite is the most widely used anode material for lithium ion batteries (LIBs), and increasing the sphericity and density of graphite is the main way to further improve energy density of LIBs. Herein, we report a simple preparation of high tap-density graphite granules by the high-shear wet granulation. In this way, we densified two kinds of graphite into granule, namely wet-granulation graphitic onion-like carbon (WG-GOC) and wet-granulation artificial graphite (WG-AG). It is found that, compared with the original graphite before granulation, the tap density of WG-GOC increases by ca.34%, and WG-AG increases by ca.44%. Therefore, when as the anode of LIBs,, the volumetric capacities of WG-GOC and WG-AG have increased by ca.35% and ca.55%, respectively, at the current density of 50 mA g−1. In addition, the rate performance of WG-GOC also has been significantly improved. The volumetric capacity of WG-GOC increased by 169.1% at the current density of 2000 mA g−1. The significant improvement of electrochemical performance benefits from the higher tap density of the prepared graphite granules. Hence, we developed a facile wet-granulation to prepare high tap-density graphite anodes, which conducive to the development of high volumetric capacity.

During twin screw granulation (TSG), small particles, which generally have irregular shapes, agglomerate together to form larger granules with improved properties. However, how particle shape impacts the conveying characteristics during TSG is not explored nor well understood. In this study, a graphic processor units (GPUs) enhanced discrete element method (DEM) is adopted to examine the effect of particle shape on the conveying characteristics in a full scale twin screw granulator for the first time. It is found that TSG with spherical particles has the smallest particle retention number, mean residence time, and power consumption; while for TSG with hexagonal prism (Hexp) shaped particles the largest particle retention number is obtained, and TSG with cubic particles requires the highest power consumption. Furthermore, spherical particles exhibit a flow pattern closer to an ideal plug flow, while cubic particles present a flow pattern approaching a perfect mixing. It is demonstrated that the GPU-enhanced DEM is capable of simulating the complex TSG process in a full-scale twin screw granulator with non-spherical particles.

The pore structure in the high-temperature zone plays a leading role in the permeability of the sinter bed. However, few studies on the bed structure in the high-temperature zone of sintering are due to the difficulty of sampling. Pilot-scale sinter pot tests were conducted to investigate the flame front propagation properties and pore evolution characteristics under different granulation moisture in this paper. Liquid nitrogen was injected to quench the sintering bed. We use X-ray computed tomography to reconstruct the high-temperature zone sinter structures. Results show that the higher porosity of green bed under higher granulation moisture results in faster flame front and more likely channels formation. The porosity of the high-temperature zone increases from 48.40% to 51.50% and 55.68% with moisture increasing from 5.30% to 6.35% and 6.91%. However, the mean length of pores decreases from 1.60 mm to 1.38 mm caused by inadequate coalesce under high moisture conditions.

This paper proposes a comparative study of two techniques of granulation of a submicronic alumina powder with high binder content slurries, by spray drying and freeze granulation for the preparation of mixed granules. First, the viscosity and flow index of the suspensions are given as a function of dispersant, solid and binder contents versus alumina content, and the data are analysed in order to give a predictive model in a wide range. Suspensions with varying viscosities (7–208 mPa.s), densities (1.31–1.76) and surface tensions (23–40 mN/m) were then granulated. The first observations reveal the importance of the content and the molar mass of the binder: when they are too high, the freeze granulation fails and filaments are produced instead of granules due to extensive stretching of the molecular chains of the binder during spraying. Then through a theoretical analysis of the phenomena leading to granulation, an original dimensionless number is proposed to describe the evolution of the granule size as a function of suspension formulation. This number is related to the Reynolds and Weber number and is able to predict the granule size over a wide range (20–500 μm for freeze granulation, and 5–30 μm for spray drying). Spray drying leads to smaller granules with various shapes, from full shape to hollow or donut-like, whereas freeze granulation leads to bigger but spherical granules with a microporosity, and a size easier to predict as no drying shrinkage is observed.

During wet granulation, the sample can be exposed to considerable mechanical effects, moisture content and elevated temperatures, and during high-shear granulation the impeller and chopper speeds can induce elevated temperatures and influence the parameters of the products. In our work, we therefore aimed to investigate the effect of cooling and process parameters on product parameters by factorial design in accordance with QbD guidelines. Our other goal was to study the effect of the type of granulation, therefore two series were used to prepare granules in a high-shear granulator, with water and binder solution as granulating fluid, at different chopper and impeller speeds with application of factorial design. The particle size was higher when cooling in the case of granules prepared with binder solution. The pepsin solution had a good granulating effect, the granules displayed a larger particle size, a higher breaking hardness and a favourable deformation process.

To carry out processes dealing with particle structures, a huge number of processing options are available. Options such as spheronization, granulation, pelletization, and agglomeration can be used to transfer powders or liquids to free-flowing granules with defined properties. In this chapter, the basics of particle formation are described and the operation principles of different types of equipment are explained. Finally, some practical examples of food formulations and processes are summarized to demonstrate the different concepts and their influence on product structures and properties.

Fluid bed coating processes are used in food processing to granulate and/or coat solid particulate ingredients. These processes originated in the 1950s and 1960s as a means to manufacture oral pharmaceutical products and include the classic designs of Wurster (bottom spray), top spray, and tangential spray as well as variations of these designs that have found a niche. Applications accomplish a variety of goals including the following: (1) reduction of fine particles or dust; (2) improved handling properties; (3) improved homogeneity; (4) color or flavor addition; (5) reduction of undesired off flavors or bad taste; (6) protective barrier coat applications to shield from oxygen, moisture, or other reactive ingredients; and (7) introduction of sustained, delayed, burst, or enteric release properties. This chapter focuses on the technical aspects of fluid bed coating and granulating processes with sections on fluidization, temperature, drying capacity, nozzles and spray, scale-up, and formulation considerations.

This work presents a study of the granulation of iron fines in a horizontal high shear granulator. Both experiments and DEM simulations were conducted to investigate the effect of water content, impeller rotational speed and particle sizes on granulation performance. The experimental results showed that the granule size increased with increasing water content, but the granules had the most uniform size at 8% of water content. The DEM model was developed to understand the inter-particle force, particle motion and adhesion during granulating. The results show that the liquid bridge force and the amount of bonded small particles increased with increasing water content, resulting in larger granules with wider granule size distributions. Increasing impeller speed also increased granulation efficiency due to increased collisions between particles. The simulation of the granulation of particles with different size ratios showed that granulation efficiency increased with increasing size ratios of nucleating and adhesive particles.

Li4SiO4 stands out among various solid sorbents for CO2 capture. The commonly used mechanical granulation process for Li4SiO4 sorbents causes the destruction of the microstructures. Therefore, with the characteristics of huge production and low cost, an agricultural waste (rice husk) was employed as a pore former to improve the structures of Li4SiO4 pellets and, thus, enhance the cyclic CO2 sorption performance. The rice husk templating greatly enhanced the CO2 sorption capacity of Li4SiO4 pellets. Especially, 20 wt% rice husk-templated Li4SiO4 exhibited the capacity of 0.21 g/g, which was nearly twice that of the unmodified sorbent. The quick release of the combustion gases from burning rice husk could create porosity for the sorbents. In addition, the alkaline compositions in rice husk promoted the CO2 sorption due to the decreased CO2 diffusion resistance by the formation of molten phases. Moreover, the ashes of rice husk after high-temperature combustion were found to block the pores of the sorbents, leading to the capacity reduction. The comprehensive function of rice husk templating for Li4SiO4 pellets was the tradeoff between the positive effects of pore creation and alkaline doping and the negative effects of pore blockage by the ashes.

Dry centrifugal granulation technique for treatment of liquid blast furnace (BF) slag stands out by its compact structure, easy adjustability, and smaller energy consumption. It is crucial to obtain fine particle characteristics for achieving high granulation performance and then high heat recovery rate. A three-dimensional model was established in this paper to describe theparticle characteristics of liquid BF slag by new hybrid centrifugal-air blast granulation technique. The intuitive granulation evolutions, particle mass distribution, and size uniformity, were acquired as well as accumulative mass fraction. As a result, the vertical breakage effect of blast air (20 m/s) accelerated the granulation process and led to a reduction of 14–18% in particle size, with more obvious optimization effect at low disk speed. Moreover, the general prediction correlation of particles size suitable for both the hybrid centrifugal-air blast technique and the classical centrifugal granulation technique, was established to optimize the granulation performance.

The plasma rotating electrode process (PREP) is rapidly becoming an important powder fabrication method in additive manufacturing. However, the low production rate of fine PREP powder limits the development of PREP. Herein, we investigated different factors affecting powder formation during PREP by combining experimental methods and numerical simulations. The limitation of increasing the rotation electrode speed in decreasing powder size is attributed to the increased probability of adjacent droplets recombining and the decreased tendency of granulation. The effects of additional Ar/He gas flowing on the rotational electrode on powder formation is determined through the cooling effect, the disturbance effect, and the inclined effect of the residual electrode end face simultaneously. A smaller-sized powder was obtained in the He atmosphere owing to the larger inclined angle of the residual electrode end face compared to the Ar atmosphere. Our research highlights the route for the fabrication of smaller-sized powders using PREP.

The present work explores the pharmaceutical application of a novel seeded granulation to develop properties-improved, high drug-loaded, and sustained-release tablets using hydroxypropylcellulose (HPC) as a binder. Itraconazole, 4-acetamidophenol, and rifaximin were selected as model drugs. They differ significantly with respect to particle size distribution and solubility. As granulated, the correlation among drug properties, binder characteristics, granulation parameters, and product attributes was discussed. Granulation was performed with 11% HPC-L at a constant impeller tip speed of 4.39 m/s and above. The liquid bridge interaction occurred when coarse particles were granulated along with fine particles. The detachment-reattachment process was responsible for the formation of core-shell seeded granules. Such granules showed good mechanical properties, strength, flowability, compactability, sustained release, high drug-loading, and uniformity. In comparison to conventional granulation, this method is cost-effective, gives better compactability, yields a reduced tablet size at a high dose, and facilitates manufacturability using standard batch granulation.

Spatial Filter Velocimetry (SFV) is a technique that has been used for agglomeration processes during the past few years as it can monitor, control, and understand granulation and its implications in particle size distribution. This work has considered and aimed to analyze the evolution of the process as time goes on and in real-time and the influence of operating conditions on the process. A Plackett-Burman design was proposed with seven factors and three replicates at the central point condition, using microcrystalline cellulose (CMC) as the raw material and a maltodextrin solution as a liquid binder. Binder concentration, binder flow rate, powder initial moisture content, and fluidizing air temperature were significant at a 90% confidence level. A new approach was proposed for delimiting the stages of the fluidized bed agglomeration process, based on particle size classes that were obtained from the SFV probe data.

Continuous manufacturing in the pharmaceutical industry has been gaining traction in the past few years. To fully understand and optimise continuous manufacturing processes it is important not only to focus on the single units which act as building blocks but also to understand how the parameters in different units affect and interact each other and the final product. In this study, the drying behaviour of granules in a segmented fluidised bed dryer was studied. Granules were produced in a twin screw granulator, forming part of a continuous powder to table line (Consigma-25). The temperature readings and the moisture content were recorded during the drying process of granules produced with different amounts of liquid binder. From the temperature profiles, it was possible to create a method able to detect when the drying process loses efficiency (the drying rate drops) and therefore predict the optimal drying time at different conditions. The method was validated via online Near Infra Red (NIR) moisture measurements to detect the moisture content of the granules during the drying, and was compared to the available fixed drying time and temperature controlled end of drying methods. The method was successful in targeting a specific moisture content and could be used to locate the optimal drying temperature for a target moisture content in the future. The moisture content during the filling of the dryer was also recorded and provided further insight into the drying behaviour of the granules in the segmented dryer; this characteristic behaviour could later be used to detect problems during the filling time. The drying rate was also calculated making it possible to predict the optimal drying time at different operating conditions in the granulator and to assess the impact on drying of the different liquid to solid ratio used.

The technological factors required to improve the operational properties of granulated metallurgical slags demanded in the building industry have been analyzed. In order to satisfy these factors, a new technology for hydro-vacuum granulation of slag melts (HVG) has been developed. It is shown that the main advantage of the proposed HVG process is the provision of forced high-speed vortex convection of water, with the effect of vertical suction, crushing, and degassing of the three-phase (water–slag granules–water vapor) heterogeneous medium formed during the overcooling and solidification of slag. It is proved that the high-speed volumetric disintegration and overcooling with the degassing effect sharply reduces a degree of aggressive gas/vapor impact on the being cooled particles of slag, which, in turn, leads to the reduction of the perforation degree of the granules. The obtained granules are distinguished by stable fractionation and improved, well-defined dense amorphous glassy structure, the water-holding capacity of which has reduced from 45–50% to 25–13%, the actual moisture content from 24–20% to 6–4%, while the hydraulic activity in terms of CaO-uptake increased from the conventional 320–360 mg/g to 610–650 mg/g. Pilot scale research demonstrated that the designed equipment for the HVG technology allows sustainable control of the quality of granules, and it has the potential for further development and implementation.

One of the tablet manufacturing processes using the wet granulation method is the process of mixing the active ingredient granules, fillers, binders and pelicans. The parameters of the mixing process are important to study because they will affect the physical properties of the tablet. This study studied the effect of the variable duration and the size of the mixing cycle on the physical properties of paracetamol tablets using a 2D double mixer. The results of the analysis and testing showed that the variation of mixing time and the size of the rotation had a significant effect on the flow properties of the granules and the hardness of the tablets. In addition, the optimal parameter results to obtain optimal tablet hardness occurred at 15 minutes of mixing process and 50 rpm of rotation.

The paper presents the research results of peat-vermiculite compositions for the production of granulated material with heat-insulating properties, that can be used in the construction of low-rise buildings. The paper considers the possibility of producing a heat-insulating granulated material based on a peat-vermiculite mixture. The obtained data on various methods of the peat-vermiculite mixture granulation are analyzed. It is found that the optimum concentration of the Akvasil water-repelling is 10% in the mixing water. This concentration allows reducing the water absorption of peat-vermiculite compositions by 16% and increasing the material strength by 20%. Further increase in the Akvasil concentration in the mixing water does not lead to a significant change in the water absorption, and the strength properties decrease.

Objective. To optimize the preparation formula and technology of Chuilian Jianpi granules. Methods. The formulation and preparation process were optimized by single factor experiment and response surface analysis, with the molding rate, hygroscopicity, and fluidity of particles as the comprehensive evaluation indexes, and the comprehensive score as the response value according to different weights. To further evaluate the stability and feasibility of the preparation formulation and technology, the physical fingerprint of the granules was constructed by seven indicators including particle tap density, bulk density, hygroscopicity, water content, angle of repose, Hausner ratio, and relative homogeneity index. Results. The optimum formula conditions of Chuilian Jianpi granules were as follows: the dosage ratio of drug to adjuvant was 1 : 0.8, lactose:mannitol = 1.5 : 1, and the amount of wetting agent (90% ethanol) was 25% of the granules, with high-speed stirring granulation. The similarity of the physical fingerprints of the 10 batches of Chuilian Jianpi granules was high, which is above 98.5%. Conclusion. The optimized preparation technology was stable and feasible, which can provide reference for the development of Chuilian Jianpi granules and other Chinese medicine granules.

Wet granulation is a size enlargement process in which fine powders are agglomerated into larger granules via the presence of a liquid binder. Among various types and modes of granulation processes, twin-screw granulation is a popular continuous wet granulation technique. The typical residence time that powders spend in a twin-screw granulator are in the order of seconds, hence, the rigorous mixing of solid and liquid particles across particle sizes and equipment geometry becomes even more important. This study aims to improve the mechanistic understanding of the effect of process and screw parameters on the mixing dynamics inside a twin-screw granulator using dispersion coefficient as a key metric. The dispersion coefficient quantifies the dispersion and is directly proportional to the extent of mixing occurring inside the granulator. An analysis of the experimentally obtained dispersion coefficient is performed to understand the effect of key process and design parameters such as feed rate, screw speed, number of kneading elements and, stagger angle. A semi-mechanistic model that incorporates these parameters was developed to estimate and predict the dispersion coefficient. The model accurately predicts the dispersion coefficient values and the goodness-of-fit values (R2) for the test set and full data set were found to be equal to 0.920 and 0.932 respectively. This model was further tested by predicting the complete RTD curves using the predicted dispersion coefficients. The average goodness-of-fit value (R2) for the prediction of RTD curves for all the experimental runs was calculated to be equal to 0.698.

Collisions between particles and the wall covered by a liquid layer play an important role in many different industrial processes (e.g., chemical, pharmaceutical, and transportation). Understanding the rebound motion law of the collision between particles and the wall covered by a liquid layer is vital to ensure the high efficiency of processes such as wet granulation and fluid catalytic cracking. In the present study, we investigated the influence of different collision angles on the liquid bridge geometry, particle motions, particle energy, and other collision details based on the oblique collisions between particles and the target plate covered by a liquid layer. Results showed that the collision angle of particles has a great effect on the liquid bridge geometry. Moreover, the liquid bridge caused by different collision angles initially increases the particle deflection angle difference and then decreases, and this influence gradually increases with the increase of the collision angle. In addition, the collision angle greatly affects the particle’s energy.

This paper provided an overview of characteristics of limonite ores as well as their influence on sintering performance. Evaluation experiments focusing on basic characteristics, granulation characteristics, and high temperature sintering characteristics had been conducted by using two types of limonite ores, then the principles of high effective utilization technology of limonite ores were discussed, and the sintering pot tests were conducted. Limonite ores possessed low total iron content, high combined water content, high SiO2 content, large average particle size, low adhering particles proportion, high porosity, high water absorption rate, short water absorbing time, poor granulation ability, high melt formation ability, low melt fluidity ability, low melt penetration ability, high melt absorption ability, low bonding phase strength, and high forming ability of SFCA. By taking the technical measures of ore-proportioning optimization, increasing the proportion of burntlime and segmentation granulation, the usage of limonite ores could reach 50% in sintering.

To solve the problem of difficult utilization of steel slag, the liquid steel slag was modified and the air-quenching granulation process was carried out to make steel slag into a value-added end product: air-quenching granulated steel slag. The granulated slag was tested to analyze the variation rule of slag properties under different modification conditions. Based on the phase diagram of CaO–Si2O–FeO–MgO–Al2O3 slag system, the feasibility of blast furnace (BF) slag as modifier was determined. When the addition of BF slag was increased from 0% to 35%, following results were obtained. The slag fluidity was improved, and the air-quenching temperature range was expanded. Then, the yield of air-quenched steel slag increased, while the granulation rate, the degree of sphericity, the compactness were decreased. Furthermore, the air-quenching granulation process could substantially improve the stability and the amorphous content of steel slag. The maximum removal rate of free CaO was above 80% and the amorphous content was up to 95%. Taking the factors of yield and properties of granulated steel slag into full consideration, the optimum proportion of BF slag is around 15%.

Comprehensive understanding of an integrated continuous pharmaceutical technology was achieved in this study by a combining design of experiments and mechanistic modeling-based simulations. The powder to granule line consisted of twin-screw wet granulation, vibrational fluid-bed drying and milling. A Partial Least Squares (PLS) regression model was built using Near-infrared (NIR) spectroscopy for the real-time monitoring of the product moisture content after the milling step. A split-plot full factorial experimental design was set up and executed to help the understanding of the relationships between the moisture content and process parameters. Furthermore, a mechanistic model was built, involving heat transfer between the drying air and the solid material. The unknown kinetic model parameters were estimated using the results of the experimental study resulting in good calibration and validation performance. The simulations not only reinforced the experimental observations but also paves the way for model-based process monitoring and optimal control.

Introduction. The stage of wet granulation is often used in the technology of solids. The method of wet granulation in a mixer-granulator with high shear force can be regarded as the most complicated method of its implementation from the engineering and technological point of view. The mixer-granulator has two mixers located in mutually perpendicular planes. Using an impeller, dry components are mixed, and the chopper, turning on when spraying a humidifier, ensures the formation of granules. By setting different chopper rotational speed, granules of different sizes can be obtained. This granulator has the following advantages: it provides a high product yield (≥ 99 %), takes up small workspaces, and the closed design ensures environmental protection.Aim. The aim of the research is to scale the granulation process, on the example of the solids production technology, using the wet granulation stage - in a mixer-granulator with high shear force.Materials and methods. Dry extract «N» and auxiliary substances were used as a pharmaceutical substance: lactose monohydrate, microcrystalline cellulose (MCC) (MICROCEL® MC-102), potato starch, povidone (Plasdone™ K-29/32), calcium stearate. Granulate under scaling conditions was produced in a mixer-granulator with high shear force. Technological properties of dry extract «N» and granulate were determined by the methods described in National pharmacopeia XIV.Results and discussion. On the basis of experimental studies, it was found that the resulting granulate, both when obtained under laboratory conditions and under scaling conditions, has good flowability, and also has a homogeneous fractional composition. The presence of a grinder in the mixer-granulator made it possible to obtain a more uniform fractional composition of the granulate. A 10-fold increase in loading did not affect the composition of the granulate. When scaling the pelletizing process, a risk analysis was carried out, factors influencing the technological process were identified and structured. It turned out that the most important stages are mixing and the actual granulation. To obtain a homogeneous mixture, additional equipment was used - a mixer.Conclusion. As a result of scaling up the granulation process, the parameters of wet granulation in the mixer-granulator (optimal loading, impeller and grinder rotation frequency), technological properties of the resulting granulate, and risks affecting the technological process were selected. were evaluated and a causal diagram (Ishikawa diagram) was drawn.

The results of an experimental study of the combined enamelling technique are presented – enamel with enamel granulation. Original enamel inserts, decorated with enamel granules of various colours and sizes, were obtained, the use of which expands the possibilities of decorative enamelling. It is shown that different degrees of fusion of the enamel grain on the prepared base gives different artistic effects. Spherical grains, qualitatively adhered to the enamel ground, give a more explicit, spectacular relief; focus on specific elements of the pictorial composition. Melted hemispherical grains give a light texture to the composition, support and complement the enamel painting. Recommendations are given on the formation of granulation, preparation of enamel soil, drawing of details, firing temperatures of enamels to obtain high-quality granulation and colourful artistic composition, as well as other technological and design aspects of the decorating process.

The aim of this formulation study was to determine the effect of the binder used in the preparation of granules by thermoplastic granulation on the release of propranolol from experimental tablets. Another aim was to select suitable excipients and their ratio in the granules to ensure a trouble-free formulation of the tablets. This study proved that the binder affects the flow properties of the granules, disintegration of the tablets and, subsequently, also the method of drug release, which can be used for the preparation of tablets with modified or prolonged drug release.

Dose dumping is the major drawback of sustained release (SR) matrices. The current research aimed to develop the stable lipid-based SR matrices of quetiapine fumarate (QTF) using Geleol™ (glyceryl monostearate; GMS) as the lipid matrix carrier and Klucel™ EF (HPC EF), Kollidon(®) VA64, and Kollidon(®) 12PF as hydrophilic binders. Formulations were developed using advanced twin screw melt granulation (TSMG) approach and the direct compression (DC) technique. Compared with the blends of DC, the granules of TSMG exhibited improved flow properties and tabletability. Solid-state characterization by differential scanning calorimetry of the prepared granules exhibited the crystalline nature of the lipid. Fourier transform infrared spectroscopy demonstrated no interaction between the formulation ingredients. The compressed matrices of TSMG and DC resulted in the sustained release of a drug over 16-24 h. Upon storage under accelerated conditions for 6 months, the matrices of TSMG retained their sustained release characteristics with no dose dumping in alcohol, whereas the matrices of DC resulted in the dose dumping of the drug attributing to the loss of matrix integrity and phase separation of lipid. Thus, it is concluded that the uniform distribution of a softened binder into a molten lipid carrier results in the stable matrices of TSMG.

Spray granulation was used to control morphology and particle size of raw materials for spheroidization in this work. Effects of dispersant (PAA-NH4OH) addition, pH value and solid content on stability of slurry for granulation was investigated. Influence of solid content of the slurry and atomizer speed on spray granulation were also investigated. Furthermore, difference in spheroidization effect between Ti-6Al-4V powder spheroidized from the granulated powder and irregular powder was compared. Results show that zeta potential of the slurry can be controlled at -44 mV to by addition of dispersant when pH value is 9.3. Granulated powder prepared with 50 wt% solid content and 10,000 rpm atomizer speed was best for plasma spheroidization. Ti-6Al-4V powder spheroidized from the granulated powder has better properties than that spheroidized from irregular powder. Spheroidization ratio, flow properties and apparent density of the spheroidized Ti-6Al-4V powder from granulated powder are 98%, 35.4 g/50s and 3.2 g/cm3, respectively.

In leading countries around the world, research is being conducted on the development of dry slag granulation plants (DSGPs) for blast-furnace slag; these plants support production of dry granulated slag and recovery of physical heat from slag. The design and construction of laboratory or pilot dry granulation plants requires engineering techniques that can be used to design the major components of the plant. The most important component of a dry slag granulation plant is a horizontally rotating device (disk) for spraying slag (a disk), with the molten slag being fed onto this disk. As the slag interacts with the disk, the slag is atomized into drops with a diameter of 1–2 mm that move radially at a speed of 5–15 m/sex through the interior of the granulation chamber, where they undergo radiant and convective heat exchange, and solidify before they come into contact with the cylindrical wall of the chamber. Knowing the maximum diameter d of the molten slag droplets and the speed w at which they move through the granulation chamber, it is possible to estimate the geometric and operating parameters of the spraying device (disk): The disk radius r0, the rotation frequency f of the disk, the maximum slag flow rate Gmax at which the slag becomes atomized, as well as the mechanical power N required for rotation of the disk. In this paper, we obtain fairly simple expressions that enable us to determine the values of r0, f, Gmax, and N as a function of the parameters d and w, and present the results from an analysis of these functions. This analysis also takes into account the thermophysical properties of blast furnace slag: density, coefficient of viscosity, and the coefficient of surface tension. For example, slag droplets with diameter 2 mm and speed 5 m/sec cool in the granulation chamber from 1500 to 1200°C (guaranteed solidification temperature) in about 0.7 sec, in which case the radius of the chamber should be at least 3.5 m. The rotating disk should be approximately 0.047 m in diameter, with a rotation frequency of 16.8 Hz. The maximum volume flow rate of sprayed slag is 0.0035 m3/sec = 12.6 m3/h. The specific consumption of mechanical energy for the disk drive will be ≈ 0.0105 kW·h per metric ton of molten slag. As the droplet velocity w increases, the size of the granulation chamber and the values of r0, Gmax, N will increase significantly, and the rotation frequency of the disk will decrease. As the droplet diameter d decreases, the size of the granulation chamber and the values of r0 and Gmax will significantly decrease, the frequency f will increase, and there will be a slight increase in the power N.

Objectives. This paper presents research results on the encapsulation of a fluidized bed of liquid and solid toxic waste containing chemicals with a hazard class of 1–3.Methods. Soils contaminated with hexachlorobenzene and hexachlorocyclohexane were used as the seed material. Ceresin was selected as the encapsulant, which was sprayed onto the fluidized bed through a pneumatic nozzle at a temperature of 135°C. Before the spraying of the ceresin, binders were introduced into the fluidized bed of the seed material through pneumatic nozzles in the form of a melt of high-temperature coal-tar pitch and wastewater containing sodium and arsenic salts as well as heavy metal oxides. The experiments were carried out using a modified GLATT AGT-150 laboratory unit.Results. The results demonstrate that the mechanism for granule formation is a mixed mechanism. The binding of the seed material is carried out by both the pitch and salting out. In this case, the cavities in the agglomerates are partially filled with salt deposits, which increases the strength and integrity of the final product’s structure. Ranges for the process parameter values were established at the point at which there was no unwanted agglomeration in the fluidized bed, and dust formation did not exceed 5%. When the ratio of the bed mass to the mass of ceresin is equal to unity, a moisture-resistant free-flowing product of hazard class 5 is obtained, which is suitable for transportation and long-term storage. The average diameters of the initial particles and encapsulated granules were 0.5 and 1.5 mm, respectively.Conclusions. The present study demonstrates a potential process for the granulation– encapsulation of toxic waste and hazardous substances with a hazard class of 1–3 in a single fluid-bed apparatus, resulting in the formation of a moisture-resistant hazard class-5 granular product suitable for transportation and long-term storage. The results obtained can be used in the development of an industrial large-scale process for encapsulating waste of hazard classes 1–3.

With the rapid growth of the world’s informatics innovation, printed circuit boards (PCBs) processing produces wastewaters with copper and nickel ions. This study aims to remove and recover copper and nickel ions from synthetic PCB wastewater using a fluidized-bed homogeneous granulation process (FBHGP). FBHGP is an advanced green technology that removes copper and nickel and transforms the sludge into a hard granule. The impacts on the removal and granulation of copper and nickel of the initial operating pH, molar ratio (MR) of precipitant to metal, and precipitant flow rate have been evaluated. The highest copper removal was attained at 97% at pH of 6.5 and 98% copper removal at an MR of 2.0 and 10 mL·min-1. A 93% copper granulation was achieved at the same pH, while a 94% copper granulation was also achieved at the same MR and precipitant flow rate. At a pH of 7.5, 85% nickel removal and 74% granulation were attained for a nickel. At an MR of 1.75, 82% and 74% were the highest removal and granulation. While at 25 mL·min-1, the highest removal was 83%, and 73% nickel granulation was achieved. Copper has been successfully recovered from synthetic PCB wastewater using FBHGP. At the same time, nickel needs a multi-step FBR, which is more suitable for the recovery of nickel under the same conditions applied during the same period.

According to domestic and foreign literature, patients with the surgical profile with infected wounds and purulent-inflammatory complications make up the majority of patients. For the treatment of chronic wounds and bedsores together with the inhibition of the growth of microorganisms, a drug must provide the optimal conditions for the growth of granulation, and have the reparative and anti-inflammatory effect. One of the main modern principles of wound healing is the pathogenetic orientation according to the phase of the wound process. Therefore, one of the current problems of modern pharmacy is the development of drugs for the treatment of infected wounds and bedsores with the complex pharmacological activity. Aim. To experimentally substantiate the technological mode for production of an extemporaneous gel with decamethoxine and hyaluronic acid. Materials and methods. The gel was prepared at a temperature of 15-25 °C. The gel base was prepared according to the conventional technology. Due to the fact that the polymer was already pre-neutralized with ammonia, Aristoflex AVC (“Clariant Surfactants”, Switzerland) weighed in portions was added in the calculated amount of water and stirred at a slow speed of the agitator of 60-70 rpm (to prevent air bubbles) to form a gel, then gradually added the weighed glycerol, and aqueous solutions of active pharmaceutical ingredients (API) previously prepared. The plastically viscoelastic properties of the gel developed were studied on a BROOKFIELD DV-II + PRO viscometer. Results. During the analysis of the dependence of viscosity on the shear rate obtained it was found that the rheological behavior of the gel studied was characterized by an inverse decrease in viscosity with increasing the shear rate, i.e. there was a pseudo-plastic type of flow characteristic of coagulation-thixotropic structures, under the influence of an increasing mechanical load on which the structural associates were destroyed. The ascending and descending curves formed “hysteresis loops”, indicating the thixotropy of the systems capable of recovery after destruction. Thus, we can assume that the resulting gel has stable plastic properties, easy to apply and distribute on the surface. It was found that the value of the mechanical stability (MS) of the gel was 1.1, and its base – 1.2. It, in turn, confirms the thixotropic properties that allow restoring the structures after stress, which occurs in the technological process of soft dosage forms. Conclusions. The study of the dependence of the structural viscosity on the shear rate gradient for the gel developed and the gel base at different temperature values (20, 34 °C) has demonstrated that the viscosity of the compositions decreases with increasing the shear rate gradient, providing the necessary process parameters (accuracy and ease of dosing) and such consumer characteristics as the optimal spreading when using the drug. It has been found that the MS value of the gel confirms its thixotropic properties, which allow restoration of the structures after the applied stresses that occur during the technological process.

In Ukraine, the problem of processing and utilization of sludge deposits that are formed during the treatment process at wastewater treatment plants is relevant. Unprocessed sewage sludge merges into overcrowded sludge sites every year, which leads to a deterioration of the environment and living conditions in Ukraine. Therefore, the aim of the work was to study the processing of sludge, the creation of pellets based on their composition with peat and biomass and their drying. The article presents the studies of drying kinetics of composite pellets based on peat, obsolete sludge and biomass on an experimental convective drying stand. The influence of the proportions of the components of the composition on the drying time was determined and the ratio at which the drying time of the pellets is shorter and the pellets are of better quality was selected. A comparison of the drying time of the sludge-peat composition and its components was performed, which shows that during the drying of the composite pellets, the intensification of the drying process is observed. The study related to the effect of the diameter of the pellets on the duration of drying showed that the duration of drying increases along with diameter. The presented comparison of drying kinetics of two- and three-component pellets shows the same nature of the drying curves and the drying time is in the range of 17 - 18 minutes. The optimal ratio of components for quality granulation was selected. The effective drying regimes of composite pellets based on silt deposits, peat and biomass were determined.

This paper presents a predictive modeling approach of the high shear wet granulation process, quantifying the difference between the steady and induction granule growth behavior. The spatial heterogeneity in liquid binder distribution and shear rate is simulated using a compartmental population balance model. The granulator is divided into two compartments based on particle motion, which consists of a circulation compartment, and an impeller compartment. In the circulation compartment, a viscous dissipation dependent coalescence kernel is adapted for the aggregation process. In the impeller compartment a shear rate dependent aggregation kernel is implemented. The model was calibrated and validated using the dynamic evolution of granule mean size (d50). The granulation dynamics are studied with respect to change in impeller speed, liquid to solid ratio, wet massing time, initial porosity, and binder viscosity. The transition from induction growth to steady growth regime with changing process conditions is demonstrated using the model. It is observed that the model captures the effect of process parameters and spatial heterogeneity on the dynamic evolution of d50.

In order to improve the whirling phenomenon of Si3N4 particles in the granulation chamber, the influence of the structure of the granulation chamber on the internal distribution is explored. Euler Euler’s two-phase flow model is established. The flow field in the combined structure granulation chamber with different layout is simulated. The volume distribution and velocity field change of Si3N4 particles in the combined structure granulation chamber with different layout are analyzed. The results show that the angle between two adjacent composite structures is 20∘, 60∘, 80∘ and completely standard the Si3N4 particles with volume fraction index greater than 0.8 account for 10.2%, 11.5%, 12.5% and 6.7% of the total volume respectively. When the combined structure is completely standard, several small convolutions are found. The whirling phenomenon in the granulation chamber is improved. When the angle between two adjacent composite structures is 20∘, 60∘, 80∘ and complete standard, the proportion of qualified particles is 59%, 64%, 66% and 68%. The fluidity index is 84, 85, 87 and 88, respectively. To sum up, the combination structure of the granulation chamber is a complete standard, it is beneficial to improve the spin phenomenon of Si3N4 particles in the granulation chamber.

Twin-screw wet granulation is a crucial unit operation in shifting from pharmaceutical batch to continuous processes, but granulation kinetics as well as residence times are yet poorly understood. Experimental findings are highly dependent on screw configuration as well as formulation, and thus have limited universal validity. In this study, an experimental design with a repetitive screw setup was conducted to measure the effect of specific feed load (SFL), liquid-to-solid ratio (L/S), and inclusion of a distributive feed screw on particle size distribution (PSD) and shape as well as residence time distribution of a hydrophilic lactose/microcrystalline cellulose based formulation. An intermediate sampling point was obtained by changing inlet ports along the screw axis. Camera-based particle size analysis (QICPIC) indicated no significant change of PSD between the first and second kneading section, except for low L/S and low SFL where fines increase. Mean residence time was approximated as a bilinear fit of L/S and SFL. Moreover, large mass flow pulsations were observed by continuous camera measurements of residence time distribution and correlated to hold-up of the twin-screw granulator. These findings indicate fast granulation kinetics and process instabilities for high mean residence times, questioning current standards of two kneading compartments for wet granulation. The present study further underlines the necessity of developing a multiscale simulation approach including particle dynamics in the future.

Iron ores always contain several forms of alumina, which may have different effect on sintering performance. In this paper, sinter pot tests were systematically conducted with various alumina types and contents by means of alumina additives substituting for the corresponding types of alumina, and the relevant action mechanism on sintering performance was clarified by the mineralogy of product sinter. The results show that kaolinite is beneficial to the granulation process rather than other three alumina types. In addition, it contributes to relatively better sintering performance while aluminous goethite ranks the only next, followed by gibbsite and free alumina. Mechanism analysis indicates that kaolinite and aluminous goethite are preferable to achieve relatively lower sinter porosity and higher amount of silico-ferrite of calcium and alumina (SFCA) compared with gibbsite and free alumina. Besides, the former two alumina types are apt to promote the formation of higher strength SFCA such as dendritic and acicular SFCA. Furthermore, much tighter interlocking texture in product sinter is formed as alumina occurs in kaolinite or aluminous goethite. Kaolinite and aluminous goethite are the preferably desirable alumina types for sintering rather than free alumina and gibbsite.

A sol-gel method using highly compacted sodium alginate (Na-ALG) granules as gelation media was developed for the synthesis of CoFe2O4 (CFO) nanoparticles in this study. The high shear wet granulation (HSWG) process was applied with the granule size distribution (GSD), as measured and simulated using the population balance model (PBM). The formation of CFO nanoparticles was confirmed by powder X-ray diffraction (XRD). The mean crystallite sizes calculated using XRD Rietveld refinement analysis matched the particle sizes observed by transmission electron microscopy (TEM). The magnetic properties of the obtained CFO nanoparticles under different heat treatment conditions were measured using a vibrating sample magnetometer (VSM) at room temperature. As the calcination temperature increased, larger particles with higher crystallinities were obtained, which resulted in the overall magnetic properties increasing logarithmically as a function of crystalline size. The maximum saturation magnetization (76.61 emu/g) was obtained using the sample calcined at 900 °C for 2 h.

This study presents the results of experiments conducted on the granulation of copper sulfide (Cu2S) melt. The granulometric characteristics of the samples are calculated as a function of the melt temperature. An increase in the melt temperature to 1,350°C promotes the formation of particles with a particle size of –10.0 +5.0 mm, and a decrease in the melt temperature to 1,250°C promotes the formation of particles with smaller size grades (i.e., –1.6 +1.0, –1.0 +0.63, and –0.63 +0.063 mm). With an increase in temperature, the mean squared deviation of particle size from the average value and the degree of polydispersity decreases to some extent. This study also estimates the influence of the melt temperature on the shape of the granules. The cooling and spheroidization times of particles during granulation at the melt temperatures of 1,250°C, 1,300°C, and 1,350°C were calculated. In the temperature range under consideration for all of the investigated size grades of particles, the cooling time exceeded the spheroidization time, which contributed to the formation of spherical particles. The melt temperature did not significantly affect the chemical composition of Cu2S granules. The main phase component of the granules was chalcosine (Cu2S) with a monoclinic lattice of more than 80%. Chalcosine (Cu2S) with a hexagonal lattice of 8% to 9% and digenite (Cu1.78S) with 4% to 12% were also identified. Dispersed inclusions of metallic copper were also detected.

Granule breakage is an important rate process in wet granulation that promotes product uniformity and controls product size and strength. In this work, a model to predict granule breakage is proposed and experimentally validated. The model assumes exponential of the surviving granules, dependent on a probability of breakage; a function of powder and binder properties, as well as operating parameters. Validation experiments were performed with a breakage-only granulator, filled with cohesive, non-granulating sand. Premade pellets made from lactose monohydrate and silicone oils were granulated at several impeller speeds, and the number of survivors was observed over time. The results revealed that the number of granules did indeed decay exponentially. It was found that the overall probability of breakage was inversely proportional to the capillary number. Moreover, the pore saturation played an important role in determining the probability of breakage, with higher pore saturations reducing breakage overall. A comparison with experimental data from literature revealed that the developed models agrees qualitatively with the experimental data, but is unable to fully capture the effect of powder properties and powder-binder interaction.

Centrifugal atomizer has been widely used to produce metal powders, slag granules through dry slag granulation process. In this process, liquid is poured at the center of the spinning disc, which disintegrates to form droplets, and becomes solid granules/powders on cooling. In this study, a numerical simulation has been carried out to estimate powder size considering phase change into the model, and the obtained results are validated with experimental measurements. Different mechanisms of powder production viz., direct powder formation, ligament to powder formation, and film to powder formation have been captured at various liquid flow rates and angular disc speed. The effect of composition of the model liquid slag and its properties like viscosity, density, surface tension, etc. has been studied using this mathematical model. Further, the effect of superheat on solidification was also considered. Finally, powder size distribution has been correlated with properties of the slag, superheat of the liquid, and process variables.

In this paper, the flying heat transfer characteristics of slag particles are studied in the process of the dry centrifugal granulation. When the solidification time of particle surface decreased b...