1. Federal University of Espirito Santo, Department of Engineering and Technologies, Brazil;2. Federal University of Uberlandia, Faculty of Chemical Engineering, Brazil;1. State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, PRChina;2. The Key Laboratory of Catalysis, China National Petroleum Corp., China University of Petroleum, Beijing 102249, PRChina;3. Department of Chemical and Biological Engineering, University of Saskatchewan, Saskatoon S7N 5A9, Canada;1. Department of Chemical Engineering, Ilam University, Ilam 69315?516, Iran;2. Department of Computer, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran;3. Department of Computer and Information Technology, Ilam University, Ilam 69315?516, Iran;4. Department of Chemical Engineering, University of the Basque Country (UPV/EHU), Sarriena s/n, Leioa, Spain;1. State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, PR China;2. The Key Laboratory of Catalysis, China National Petroleum Corp., China University of Petroleum, Beijing 102249, PR China;3. Department of Chemical and Biological Engineering, University of Saskatchewan, Saskatoon, Canada;1. Sumitomo Chemical Co., Ltd. 5-1, Sobiraki-cho, Niihama, Ehime, Japan;2. Department of Mechanical Engineering, Osaka University, 2-1, Yamada-oka, Suita, Osaka, Japan;3. Department of Safety Science, Kansai University, 7-1, Hakubai-cho, Takatsuki, Osaka, Japan
Abstract:
The difficulty of coating cohesive Geldart group C powders in a conventional fluidized bed is attributed to strong inter-particle force between fine particles leading to poor fluidization behavior. Dry coating approach involving deposition of nanosize particles on the surface of group C powders is considered to reduce the interparticle force and improve the fluidization behavior of fine powders. Polymer film coating at an individual particle level is achieved on these pre-coated fine powders in a commercially available spouting fluidized bed (MiniGlatt). The effect of operating conditions such as inlet air temperature, polymer concentration, polymer weight ratio, water percentage in solvent and spray rate of coating solution on the quality of film coating are investigated. Experimental results demonstrate that the quality of film coating goes down as polymer concentration in coating solution goes higher, whereas the lower inlet air temperature is found to enhance polymer film generation and coating quality. It is also observed that the higher polymer weight ratio promotes agglomeration without affecting the coating quality to a great extent. An optimum water ratio in acetone-water solvent as well as spray rate can be optimized to achieve superior coating quality with acceptable agglomeration ratio.Graphical abstractDry coating approach involving deposition of nanosize particles on the surface of group C powders is considered to reduce the interparticle force and improve the fluidization behavior of fine powders. Polymer film coating at an individual particle level is achieved on these pre-coated fine powders in a commercially available spouting fluidized bed (MiniGlatt). The effect of operating conditions such as inlet air temperature, polymer concentration, polymer weight ratio, water percentage in solvent and spray rate of coating solution on the quality of film coating are investigated. Experimental results demonstrate that the quality of film coating goes down as polymer concentration in coating solution goes higher, whereas the lower inlet air temperature is found to enhance polymer film generation and coating quality.
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Figure: SEM images of Aluminum-1 particles coated to investigate the effect of polymer concentration. (a, b) Spray rate 2.11 ml/min, polymer concentration 4%, inlet air temperature 40 °C, polymer weight ratio 4% and water in solvent 0%; (c, d) spray rate 2.11 ml/min, polymer concentration 16%, inlet air temperature 40 °C, polymer weight ratio 4% and water in solvent 0%.
