Investigation of the particle flowpattern and segregation in tapered fluidized bed granulators

Computational fluid dynamics and experimental study of the hydrodynamics of a gas–solid tapered fluidized bed

“…Time averaged pressure drop, bed expansion ratios at different superficial gas velocities and solid volume fractions profile with different time instant, obtained from CFD are shown in Figs. [2][3][4][5][6][7][8][9]. Experimental analyses were done to obtain the steady state pressure drop, and bed expansion ratios at different superficial gas velocities.…”

“…Schaafsma et al [5] studied particle flow pattern and segregation phenomena in tapered fluidized bed granulator using segregation experiment and positron emission particle tracking experiments (PEPT) and concluded that the flow and segregation phenomena is totally different from conventional (cylindrical) beds. Recently, Sau et al [15,16] also investigated the dynamics of tapered fluidized beds and presented models for predicting minimum fluidization velocity and maximum bed pressure drop.…”

“…with less pressure fluctuations [1]. Tapered fluidized beds are very useful for fluidization of materials with a wide particle size distribution, as well as for exothermic reactions [4] and also for extensive particle mixing [5]. Despite their widespread application, much of the development and design of tapered fluidized bed reactors have been empirical in nature as the complex behavior of gas-solid flow in these systems makes flow modeling a challenging task.…”

PEPT visualisation of particle motion in a tapered fluidised bed coater

“…Also, PEPT was used to study the particle motion in the Wurster process operated under drying conditions (Fitzpatrick et al, 2003). More recently, Schaafsma et al (2006) used PEPT to study the particle flow pattern and granule segregation in tapered fluidised bed granulators.…”

Evolution of Granule Structure and Drug Content During Fluidized Bed Granulation by X-Ray Microtomography and Confocal Raman Spectroscopy

“…However, this experiment assumes that granules from each size cut behave similarly in the fluidized bed during actual spray granulation process as they do individually. 45 Granule-granule and granule-gas interactions most probably affect the fluidization level and segregation during the granulation process. [46][47][48] The kinetic energy of the granules is lost in granule-granule collisions, and in cohesion due to the wetting.…”