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The garrulity cumulating distribution chart of jet iron oxide Fe 2 O 3 , (d) carbon black, and (e) alum by Shimadzu SALD 2101 particle seizer.
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A jet mill system was built aiming to give values for processing inorganic materials, to be used for different industry. The milling housing of the system is composed of; milling chamber, compressed air nozzles which deliver compressed air in the milling chamber to accelerate sample particles. The classifier wheel is composed of two concentric piec...
Citations
... It depends on many parameters, such as different physical and chemical properties of the material being ground: homogeneity, strength, hardness, humidity, viscosity, forces and stresses occurring in said particles, internal particle structure, material defects of ground particles, and mill construction. A random occurrence often characterizes these variables [1,[4][5][6]. ...
... The authors in [5] described changes in the structural and functional properties of starch after the jet milling process. The results of jet milling efficiency of various inorganic materials (white sand, glass, iron oxide, hard coal, potassium and aluminum) with a narrow particle size distribution were considered in [6]. As shown, the authors managed to obtain a product below 1 µm with a narrow particle size distribution. ...
... The working air is supplied to the mill by a compressor (1), and the sealing air is supplied by a vacuum pump (13). The granular material is fed to the cylindrical grinding chamber (6) gravitationally from the charging container (8). The fed material undergoes extensive fluidization employing air jets from the nozzles (5). ...
The milling process is a complex phenomenon dependent on various technological and material parameters. The development of a fluidized bed jet milling model is of high practical significance, since milling is utilized in many industries, and its complexity is still not sufficiently recognized. Therefore, this research aims to optimize fluidized bed jet milling with the use of fuzzy logic (FL) based approach as one of the primary artificial intelligence (AI) methods. The developed fuzzy logic model (FLMill) of the investigated process allows it to be described as a non-iterative procedure, over a wide range of operating conditions. Working air pressure, rotational speed of the classifier rotor, and time of conducting the test are considered as inputs, while mass and mean Sauter diameter of the product are defined as outputs. Several triangular and constant linguistic terms are used in the developed FLMill model, which was validated against the experimental data. The optimum working air pressure and the test’s conducting time are 500 kPa and 3000 s, respectively. The optimum rotational speed of the classifier is equal to 50 s−1, considering the mass of the grinding product, and 250 s−1 for the mean Sauter diameter of the product. Such operating parameters allow obtaining 243.3 g of grinding product with the mean Sauter diameter of 11 µm. The research proved that the use of fuzzy logic modeling as a computer-based technique of solving mechanical engineering problems allows effective optimization of the fluidized bed jet milling process.
... The spiral flow field in these mills provides particle size classification, especially at the outlet tube in the center of the mill (Rodnianski et al., 2013), i.e. stressing and classification are entangled (Midoux et al., 1999;Müller & Polke, 1999). In contrast, in fluidized bed opposed jet mills, several jets are focused onto a focal point that lies inside a fluidized bed (Al-Nuzal & Mohammed, 2017;Fukunaka et al., 2006). Here, particle crushing occurs due to collisions at the focal point and in the periphery of the expanding gas jets where the particles are entrained. ...
Fluidized bed opposed jet mills are capable of meeting the continuously growing demand for contamination-free fine particles. In this type of jet mill, the solid material is entrained and accelerated by expanding gas jets that are focused onto a focal point inside a fluidized bed. The resulting particle collisions induce breakage. The process is affected by the relative particle velocities and the number of particle–particle collisions. Clearly, both quantities are distributed. However, to date, neither relative particle velocities nor collision frequencies in such units have been determined. The present work introduces an innovative method to assess the stressing conditions in jet mills experimentally. To this end, mixtures of glass and ductile metal microspheres were used, with the latter employed in small amounts. Inter-particle collisions between the aluminum and glass spheres lead to the formation of dents on the microparticles. The size and number of these dents are associated with the individual collision velocities and overall collision frequencies. The correlation between dent size and collision velocity was obtained from finite element calculations based on empirical data. The proposed approach was validated using particle image velocimetry during secondary gas injection into a fluidized bed reactor. In this case the effect of the distance between two opposed nozzles was examined. For a lab-scaled fluidized bed opposed jet mill the effects of gas pressure and hold-up were investigated. Relative particle velocities were found to be significantly lower than the gas velocities, while the number of contacts per particle was determined to be extremely high.
In this study, pyrolysis carbon black (CBp) was pre-treated by the combination of air jet milling and Ar plasma technology to obtain the reinforcing filler, MP-CBp. The modification effect was verified by XPS, Raman spectroscopy and TEM images. The increment of introduced activation groups and the augmentation of surface area conferred MP-CBp an impressive reinforcement to natural rubber (NR) matrix. The excellent reinforcement of MP-CBp was attributed to the formation of strong filler network according to the mechanical properties. Besides, the tribological studies conducted under various load conditions revealed that the NR component filled with MP-CBp presented intensively improvement on the ground traction and the wear resistance. The addition of 60 phr MP-CBp intensified 20% dry traction, 33.3% wet traction and decreased 27.7% specific wear rate of NR vulcanizates. This strategy to modify CBp with cleanliness Ar plasma technique provides novel insights into not only the surface treatment of CBp, but also the manufacture of sustainable wear-resistant tire materials, which can tremendously promote the recycled utilization of waste tires.
