Documents disponibles écrits par cet auteur

Analysis of Segregation Data for a Dry Mineral-Based Construction Materials Plant / Niklas Engblom in Industrial & engineering chemistry research, Vol. 51 N° 27 (Juillet 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 27 (Juillet 2012) . - pp. 9427-9440 Titre : Analysis of Segregation Data for a Dry Mineral-Based Construction Materials Plant Type de document : texte imprimé Auteurs : Niklas Engblom, Auteur ; Henrik Saxén, Auteur ; Ron Zevenhoven, Auteur Année de publication : 2012 Article en page(s) : pp. 9427-9440 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Construction  materials  Segregation Résumé : In this work, segregation data for seven commercial products at a dry mineral-based construction materials plant have been analyzed. The segregation manifests itself as an increase of the fines content to unacceptable levels at the end of complete emptying from a surge silo situated upstream of packing. Results for preliminary tests for sifting segregation and fluidization show the difficulty in estimating a priori the segregation patterns observed in practice. Knowledge of the segregation mechanisms occurring with similar materials at silo filling and the discharge flow pattern is utilized to explain the segregation at silo emptying: Accumulation of fine particles at the silo walls during filling and discharge in expanded flow cause fines-rich regions from the vicinity of walls in the lower parts of the silo to be withdrawn last. Large variations in the magnitude of segregation for each product cannot be explained for example by production run size, but are caused by size variations in the silo input, uneven distribution of fines over the heap surface during filling, unpredictable stagnant zones during discharge, and sampling procedure. Segregation at discharge mainly increases with increasing particle size distribution, but the product with the widest size distribution does not segregate the most. The width of the particle size distribution for the products correlates with the mass fraction of fine particles, and inclusion of a special additive (synthetic fibers) in very small proportions is also seen to affect segregation. Therefore, a regression model based on the mass fraction of fines and fibers was employed to organize the products according to the magnitude of segregation. Results for the model show that segregation does not always increase with an increase in the width of the particle size distribution and is negatively affected by inclusion of light and elongated particles (fibers). ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26132280 [article] Analysis of Segregation Data for a Dry Mineral-Based Construction Materials Plant [texte imprimé] / Niklas Engblom, Auteur ; Henrik Saxén, Auteur ; Ron Zevenhoven, Auteur . - 2012 . - pp. 9427-9440. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 27 (Juillet 2012) . - pp. 9427-9440 Mots-clés : Construction  materials  Segregation Résumé : In this work, segregation data for seven commercial products at a dry mineral-based construction materials plant have been analyzed. The segregation manifests itself as an increase of the fines content to unacceptable levels at the end of complete emptying from a surge silo situated upstream of packing. Results for preliminary tests for sifting segregation and fluidization show the difficulty in estimating a priori the segregation patterns observed in practice. Knowledge of the segregation mechanisms occurring with similar materials at silo filling and the discharge flow pattern is utilized to explain the segregation at silo emptying: Accumulation of fine particles at the silo walls during filling and discharge in expanded flow cause fines-rich regions from the vicinity of walls in the lower parts of the silo to be withdrawn last. Large variations in the magnitude of segregation for each product cannot be explained for example by production run size, but are caused by size variations in the silo input, uneven distribution of fines over the heap surface during filling, unpredictable stagnant zones during discharge, and sampling procedure. Segregation at discharge mainly increases with increasing particle size distribution, but the product with the widest size distribution does not segregate the most. The width of the particle size distribution for the products correlates with the mass fraction of fine particles, and inclusion of a special additive (synthetic fibers) in very small proportions is also seen to affect segregation. Therefore, a regression model based on the mass fraction of fines and fibers was employed to organize the products according to the magnitude of segregation. Results for the model show that segregation does not always increase with an increase in the width of the particle size distribution and is negatively affected by inclusion of light and elongated particles (fibers). ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26132280

Effects of material properties on segregation of binary and ternary powder mixtures in a small scale cylindrical silo / Niklas Engblom in Industrial & engineering chemistry research, Vol. 50 N° 19 (Octobre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 19 (Octobre 2011) . - pp. 11097-11108 Titre : Effects of material properties on segregation of binary and ternary powder mixtures in a small scale cylindrical silo Type de document : texte imprimé Auteurs : Niklas Engblom, Auteur ; Henrik Saxén, Auteur ; Ron Zevenhoven, Auteur Année de publication : 2011 Article en page(s) : pp. 11097-11108 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Silo  Powder  Segregation  Properties  of  materials Résumé : The segregation of binary and ternary particulate mixtures at filling and at discharge of a 0.4 m3 cylindrical silo has been investigated experimentally. Raw materials used in commercial construction products are utilized and include bulk solids with different particle size, solid density and shape. Mixtures with varying mass fractions, particle size ratio or size distribution, particle solid density ratio and flow properties (free-flowing to cohesive) are prepared. Discharge flow patterns are determined either visually or by using tracer particles. This work gives qualitative information on the influence of material properties on the embedding, (impact) fluidization and air-current segregation mechanisms, which are relevant for the handling of commercial dry mineral-based construction materials in silos of industrial scale. The results show that material properties have a significant effect on the distribution of the powder mixture at silo filling, while the material distribution at filling and the discharge flow pattern determine the composition at emptying. At filling, mixture composition (component mass fractions) determines the segregation pattern, that is, whether fines are accumulated in the center or at the silo walls. For the latter, segregation is aggravated by increasing the particle size ratio between coarse and fine component for a binary mixture or size distribution for a ternary mixture, or by reducing the particle solid density ratio between fine and coarse component significantly below unity. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24573307 [article] Effects of material properties on segregation of binary and ternary powder mixtures in a small scale cylindrical silo [texte imprimé] / Niklas Engblom, Auteur ; Henrik Saxén, Auteur ; Ron Zevenhoven, Auteur . - 2011 . - pp. 11097-11108. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 19 (Octobre 2011) . - pp. 11097-11108 Mots-clés : Silo  Powder  Segregation  Properties  of  materials Résumé : The segregation of binary and ternary particulate mixtures at filling and at discharge of a 0.4 m3 cylindrical silo has been investigated experimentally. Raw materials used in commercial construction products are utilized and include bulk solids with different particle size, solid density and shape. Mixtures with varying mass fractions, particle size ratio or size distribution, particle solid density ratio and flow properties (free-flowing to cohesive) are prepared. Discharge flow patterns are determined either visually or by using tracer particles. This work gives qualitative information on the influence of material properties on the embedding, (impact) fluidization and air-current segregation mechanisms, which are relevant for the handling of commercial dry mineral-based construction materials in silos of industrial scale. The results show that material properties have a significant effect on the distribution of the powder mixture at silo filling, while the material distribution at filling and the discharge flow pattern determine the composition at emptying. At filling, mixture composition (component mass fractions) determines the segregation pattern, that is, whether fines are accumulated in the center or at the silo walls. For the latter, segregation is aggravated by increasing the particle size ratio between coarse and fine component for a binary mixture or size distribution for a ternary mixture, or by reducing the particle solid density ratio between fine and coarse component significantly below unity. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24573307