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and discharge in expanded flow cause fines-rich regions from the vicinity of walls in the lower parts of the silo to be withdrawn last.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

Flow of pellet and coke particles in and from a fixed chute / Yaowei Yu in Industrial & engineering chemistry research, Vol. 51 N° 21 (Mai 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 21 (Mai 2012) . - pp. 7383-7397 Titre : Flow of pellet and coke particles in and from a fixed chute Type de document : texte imprimé Auteurs : Yaowei Yu, Auteur ; Henrik Saxén, Auteur Année de publication : 2012 Article en page(s) : pp. 7383-7397 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Pellet Résumé : The velocity distribution of particles in the chute of a bell-less charging equipment affects the burden segregation and distribution in the blast furnace. This paper studies the angular and translational velocity distributions of particles during their flow along and from an inclined fixed chute through experiments and simulations by the discrete element method. The simulation results are validated by comparison with observed mass fractions collected in boxes at the end of the falling trajectories and by measuring the average velocity of particles along the chute. Angular and translational velocity distributions along and across the chute are reported, and the effect of the particle size distribution and particle shape are studied. The results show that the angular velocity distribution in cross sections of the chute exhibits a V-shaped appearance, that is, opposite the distribution of the translational velocity. The mass fractions of the particles in the trajectories show a similar distribution, regardless of particle size and shape. The mean angular velocity increases and the translational velocity decreases with a growing particle size distribution, while particle shape only influences the angular velocity. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201362n [article] Flow of pellet and coke particles in and from a fixed chute [texte imprimé] / Yaowei Yu, Auteur ; Henrik Saxén, Auteur . - 2012 . - pp. 7383-7397. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 21 (Mai 2012) . - pp. 7383-7397 Mots-clés : Pellet Résumé : The velocity distribution of particles in the chute of a bell-less charging equipment affects the burden segregation and distribution in the blast furnace. This paper studies the angular and translational velocity distributions of particles during their flow along and from an inclined fixed chute through experiments and simulations by the discrete element method. The simulation results are validated by comparison with observed mass fractions collected in boxes at the end of the falling trajectories and by measuring the average velocity of particles along the chute. Angular and translational velocity distributions along and across the chute are reported, and the effect of the particle size distribution and particle shape are studied. The results show that the angular velocity distribution in cross sections of the chute exhibits a V-shaped appearance, that is, opposite the distribution of the translational velocity. The mass fractions of the particles in the trajectories show a similar distribution, regardless of particle size and shape. The mean angular velocity increases and the translational velocity decreases with a growing particle size distribution, while particle shape only influences the angular velocity. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201362n

Model for fast computation of blast furnace hearth erosion and buildup profiles / Johnny Brannbacka in Industrial & engineering chemistry research, Vol. 47 N°20 (Octobre 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 N°20 (Octobre 2008) . - P. 7793-7801 Titre : Model for fast computation of blast furnace hearth erosion and buildup profiles Type de document : texte imprimé Auteurs : Johnny Brannbacka, Auteur ; Henrik Saxén, Auteur Année de publication : 2008 Article en page(s) : P. 7793-7801 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Blast  furnace  hearth Résumé : A model for estimation of the profiles of erosion and buildup material in the hearth of an ironmaking blast furnace has been developed. The model is based on thermocouple readings in the hearth wall and bottom and solves an inverse heat transfer problem for two-dimensional slices of the hearth geometry to estimate the inner profile. Special attention has been paid to the mathematical formulation of the problem at hand, yielding a general model optimized for fast computation. This includes a flexible formulation of the boundary conditions, a generic setup of the lining materials applied in the hearth refractory, and a sophisticated iterative procedure in the estimation of the location of the internal profile. These steps have led to a model that facilitates process analysis with estimation and reestimation of the furnace hearth conditions over whole campaigns using different parameter settings. The model has been applied to study the evolution of the hearth erosion and buildup formation processes in several industrial furnaces. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800384q [article] Model for fast computation of blast furnace hearth erosion and buildup profiles [texte imprimé] / Johnny Brannbacka, Auteur ; Henrik Saxén, Auteur . - 2008 . - P. 7793-7801. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 N°20 (Octobre 2008) . - P. 7793-7801 Mots-clés : Blast  furnace  hearth Résumé : A model for estimation of the profiles of erosion and buildup material in the hearth of an ironmaking blast furnace has been developed. The model is based on thermocouple readings in the hearth wall and bottom and solves an inverse heat transfer problem for two-dimensional slices of the hearth geometry to estimate the inner profile. Special attention has been paid to the mathematical formulation of the problem at hand, yielding a general model optimized for fast computation. This includes a flexible formulation of the boundary conditions, a generic setup of the lining materials applied in the hearth refractory, and a sophisticated iterative procedure in the estimation of the location of the internal profile. These steps have led to a model that facilitates process analysis with estimation and reestimation of the furnace hearth conditions over whole campaigns using different parameter settings. The model has been applied to study the evolution of the hearth erosion and buildup formation processes in several industrial furnaces. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800384q