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Chloride Particles (chloride + particle)
Selected AbstractsHydrodynamic Characteristics of a Powder-Particle Spouted Bed with Powder Entrained in Spouting GasTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2005Qunyi Zhu Abstract Spouting of 3.7 mm polyvinyl chloride particles in a cone-based cylindrical column is subjected to entrainment of FCC powder in the spouting air. It is found that the powder entrainment reduces the minimum spouting velocity, increases the bed pressure drop and reduces the maximum spoutable bed height. At any given bed height and value of U/Ums, there is a critical value of powder loading ratio above which spouting gives way to slugging. Le jaillissement de particules de chlorure de polyvinyle dans une colonne cylindrique à base conique a été soumis à un entraînement de poudre de FCC dans l'air jaillissant. On a trouvé que l'entraînement de poudre réduisait la vitesse de jaillissement minimale, augmentait la perte de charge de lit et réduisait la hauteur maximum de lit jaillissant. À toute hauteur de lit et valeur de U/Ums données, il existe une valeur critique du rapport de charge de poudre au-dessus duquel le jaillissement conduit au pistonnage. [source] The effect of desflurane on filtration performance of breathing system filters,ANAESTHESIA, Issue 8 2010Y. Poonawala Summary This study assessed the effect of desflurane on the filtration performance of six breathing system filters intended for use with adults. Three filters contained an electrostatic filter material and three contained a pleated glass fibre filter material. Five samples of each model of filter were exposed to 6% v/v of desflurane for 1 h, 12% v/v of desflurane for 1 h, 12% v/v of desflurane for 4 h and air only for 1 h. Five samples of each filter were also tested without exposure to any vapour or air. The filtration performance was measured by challenging each filter with an aerosol of sodium chloride particles using a Moore's test rig. Penetration of particles through the electrostatic filters increased following exposure to a higher concentration of desflurane for a longer duration (p < 0.001). The effect on two of the pleated filters was not significant (p = 0.55 and p = 0.64). The effect on the remaining pleated filter was significant (p < 0.001) but small. The efficiency of some filters decreases when they are exposed to high concentrations of desflurane for a long duration. This effect appears more marked in electrostatic filters compared with pleated filters. [source] Measuring the filtration performance of breathing system filters using sodium chloride particles*ANAESTHESIA, Issue 2 2002apparatus The filtration performance of 33 breathing system filters (nine pleated hydrophobic and 24 electrostatic filters) was measured using sodium chloride particles. The particles had a size distribution with a count median diameter of 0.07 µm and a geometric standard deviation not exceeding 1.83. The geometric mean penetration values ranged from 0.002 to 0.67% for the nine pleated hydrophobic filters and from 0.25 to 35% for the 24 electrostatic filters (p <,0.0001 for the difference between the two filter types). The filtration performance obtained when filters are challenged with either sodium chloride particles or microbes is compared and discussed. [source] Re-entrainment of wall deposits from a laboratory-scale spray dryerASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 2 2007M. J. Hanus Abstract This work has determined the magnitude of re-entrainment and established the operational parameters that may be manipulated to influence re-entrainment of salt particles for a small-scale spray dryer (Buchi B-290). The wetness of the spray dryer wall deposits was found to significantly influence the magnitude of re-entrainment. It was shown both experimentally and numerically that wet deposits form at low nozzle air-to-liquid ratios (<2000), which form large droplets that dry slowly, while the initial droplet velocity did not have a large influence on wet deposition. Wet deposits form strong liquid and solid bridges, and thus deposits formed from wet particles were difficult to re-entrain. Less than 2% of deposits formed at nozzle air-to-liquid ratios less than 2000 were re-entrained, while 15.4 to 21.2% of dry deposited particles (formed at nozzle air-to-liquid ratios ranging from 2308 to 3409) were re-entrained. The threshold re-entrainment velocity of sodium chloride particles in the Buchi B-290 spray dryer was found to be between 4 and 7.7 ms,1, which is consistent with the lower-end threshold velocities presented in the literature. No significant trend relating relative humidity to the magnitude of re-entrainment was found in the 0.2,7.4% average relative humidity range, suggesting that the adhesive forces in spray dryer wall deposits are fairly constant across this relative humidity range. Decreasing wall deposit wetness through use of high (>2000) nozzle air-to-liquid ratios and use of high main gas velocities increased the re-entrainment of wall deposits in this spray dryer. Copyright © 2007 Curtin University of Technology and John Wiley & Sons, Ltd. [source] | ||||||||||