Documents disponibles écrits par cet auteur

Operating strategy to produce consistent CSD in combined antisolvent-cooling crystallization using FBRM / Martin Wijaya Hermanto in Industrial & engineering chemistry research, Vol. 51 N° 42 (Octobre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 42 (Octobre 2012) . - pp. 13773-13783 Titre : Operating strategy to produce consistent CSD in combined antisolvent-cooling crystallization using FBRM Type de document : texte imprimé Auteurs : Martin Wijaya Hermanto, Auteur ; Pui Shan Chow, Auteur ; Reginald B. H. Tan, Auteur Année de publication : 2012 Article en page(s) : pp. 13773-13783 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Crystallization  Cooling Résumé : In this study, an operating strategy which uses focused beam reflectance measurement (FBRM) to achieve consistent product quality in a combined antisolvent-cooling crystallization process is developed. The proposed operating strategy involves rapid generation of seed crystals by antisolvent addition, which is followed by a seed conditioning process through gentle heating. Subsequently, the conditioned seed crystals are grown by combined antisolvent addition and cooling. FBRM statistics were used as indications for switching from one operating region to the subsequent one. The operating strategy is demonstrated for the crystallization of paracetamol in acetone-water solution and glycine in water-ethanol solution. The crystal size distribution (CSD) produced by this operating strategy is significantly more consistent than that produced by the unseeded antisolvent crystallization and slightly more consistent than that produced by seeded antisolvent crystallization. The proposed operating strategy also reduces agglomerations in product crystals substantially and is robust in the presence of initial concentration disturbances. Furthermore, a new implementation of a distance measure is proposed for quantitative assessment of product CSD consistency. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26508201 [article] Operating strategy to produce consistent CSD in combined antisolvent-cooling crystallization using FBRM [texte imprimé] / Martin Wijaya Hermanto, Auteur ; Pui Shan Chow, Auteur ; Reginald B. H. Tan, Auteur . - 2012 . - pp. 13773-13783. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 42 (Octobre 2012) . - pp. 13773-13783 Mots-clés : Crystallization  Cooling Résumé : In this study, an operating strategy which uses focused beam reflectance measurement (FBRM) to achieve consistent product quality in a combined antisolvent-cooling crystallization process is developed. The proposed operating strategy involves rapid generation of seed crystals by antisolvent addition, which is followed by a seed conditioning process through gentle heating. Subsequently, the conditioned seed crystals are grown by combined antisolvent addition and cooling. FBRM statistics were used as indications for switching from one operating region to the subsequent one. The operating strategy is demonstrated for the crystallization of paracetamol in acetone-water solution and glycine in water-ethanol solution. The crystal size distribution (CSD) produced by this operating strategy is significantly more consistent than that produced by the unseeded antisolvent crystallization and slightly more consistent than that produced by seeded antisolvent crystallization. The proposed operating strategy also reduces agglomerations in product crystals substantially and is robust in the presence of initial concentration disturbances. Furthermore, a new implementation of a distance measure is proposed for quantitative assessment of product CSD consistency. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26508201

Residence time distribution of liquid and solid phases in a novel staged crystallizer / Zai Qun Yu in Industrial & engineering chemistry research, Vol. 48 N° 22 (Novembre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 22 (Novembre 2009) . - pp. 10047–10054 Titre : Residence time distribution of liquid and solid phases in a novel staged crystallizer Type de document : texte imprimé Auteurs : Zai Qun Yu, Auteur ; Pui Shan Chow, Auteur ; Reginald B. H. Tan, Auteur Année de publication : 2010 Article en page(s) : pp. 10047–10054 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Staged  crystallizer Résumé : A novel vertically staged continuous crystallizer is proposed in this work. It consists of a series of compartments stacked one above another with partition plates in between. A stirrer shaft with multiple impellers provides agitation in each compartment. Solution to be crystallized enters the crystallizer from the top and flows downward through all stages. Crystal product and mother liquor are collected from the bottom. Openings in partition plates with accessories attached serve as passages for slurry flow, allowing for control over interstage mixing of liquid phase and residence time distribution (RTD) of crystals. The hydrodynamics of such a crystallizer is investigated in a two-stage experimental setup. Water, PVC particles, and glass beads are used to investigate the influences of design and operating factors on interstage mixing of liquid phase and RTDs of both liquid and solid phases. Results show that interstage mixing of liquid phase can be repressed successfully to ensure the establishment of supersaturation gradient across stages. RTD of solid phase can be manipulated by adjusting the feeding rate of liquid phase and opening size in the partition plate. Average residence time of solids deceases with increasing particle size, leading to classification of particles. A model is proposed for the RTD of solid phase which agrees with experimental data very well. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9006722 [article] Residence time distribution of liquid and solid phases in a novel staged crystallizer [texte imprimé] / Zai Qun Yu, Auteur ; Pui Shan Chow, Auteur ; Reginald B. H. Tan, Auteur . - 2010 . - pp. 10047–10054. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 22 (Novembre 2009) . - pp. 10047–10054 Mots-clés : Staged  crystallizer Résumé : A novel vertically staged continuous crystallizer is proposed in this work. It consists of a series of compartments stacked one above another with partition plates in between. A stirrer shaft with multiple impellers provides agitation in each compartment. Solution to be crystallized enters the crystallizer from the top and flows downward through all stages. Crystal product and mother liquor are collected from the bottom. Openings in partition plates with accessories attached serve as passages for slurry flow, allowing for control over interstage mixing of liquid phase and residence time distribution (RTD) of crystals. The hydrodynamics of such a crystallizer is investigated in a two-stage experimental setup. Water, PVC particles, and glass beads are used to investigate the influences of design and operating factors on interstage mixing of liquid phase and RTDs of both liquid and solid phases. Results show that interstage mixing of liquid phase can be repressed successfully to ensure the establishment of supersaturation gradient across stages. RTD of solid phase can be manipulated by adjusting the feeding rate of liquid phase and opening size in the partition plate. Average residence time of solids deceases with increasing particle size, leading to classification of particles. A model is proposed for the RTD of solid phase which agrees with experimental data very well. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9006722