Effect of Particle Properties on Fluidized Powder Conveying in a Horizontal Channel

Abstract

This study experimentally investigated the dense phase pneumatic conveying in a horizontal rectangular channel using the fluidizing air. The powder used the glass beads belongs to Geldart B particle, where the mean particle diameter is 127 m, the particle density is 2623kg/m 3 and the minimum fluidizing velocity is 12.3mm/s. The experimental device consists of a powder discharge vessel, a horizontal rectangular channel at the side of vessel and the air supply section at the bottom of the vessel and the horizontal channel. The powder was fluidized by air through the porous membrane of the air supply section at the bottom of the vessel and the horizontal channel. Then, this system can be conveyed the fluidized powder. As the result, we confirmed the requirement that the fluidizing air to the bottom of the powder discharge vessel was required to the powder conveying of this system, and that the fluidizing velocity at the bottom of the horizontal channel was larger than that of the minimum fluidizing velocity. This result means that the fluidizing velocity at the bottom of the vessel and the horizontal channel is important to obtain the stable powder conveying. The mass flow rate and solid loading ratio were estimated by the measured data of the mass of transported powder. In addition, these results were compared with the conveying characteristic of the glass beads of 53 m belongs to Geldart A particle. Then, the mass flow rate of Geldart A particle was higher than that of Geldart B particle. The solid loading ratio of the Geldart A particle was also greatly large to that of Geldart B particle. Therefore, we considered that the high conveying efficiency to Geldart A particle was obtained, when the dimensionless fluidizing velocities at the bottom of the powder discharge vessel and the horizontal channel were same condition.

Design optimization of a fluidized bed with a novel air chamber using the CFD-Taguchi method

“…At this time, if the area of the fluidized bed is large and the bed is thin, abnormal fluidization states such as channeling will easily appear; if the area of the fluidized bed is small and the bed is thick, abnormal fluidization states such as bubble and surge will easily appear; and if the material diameter difference is large, abnormal fluidization states such as stratification will easily appear. 8,9 Recently, a new concept called ‘packed–fluidization’ has been introduced, which eliminates these drawbacks and changes the hydrodynamic characteristics of the bed. 10 However, it is of limited help to improve the uniformity of fluid distribution in the fluidized bed, and some scholars turn to study the interaction mechanism between plenum and gas–solid fluidized bed.…”

Research on the Pressure Dropin Horizontal Pneumatic Conveying for Large Coal Particles

“…Ebrahimi [10] established a horizontal pneumatic conveying test-bed based on a laser Doppler velocimeter, and carried out the conveying experiments of spherical glass powder with particle size of 0.81 mm, 1.50 mm and 2.00 mm. Ogata [11] studied the influence of different glass particle properties on the fluidization dense-phase pneumatic conveying system in a horizontal rectangular pipeline. Makwana [12] studied the causes of the fluctuation of the pneumatic conveying in the horizontal pipeline and showed that the pressure loss in the pipeline increased sharply with the formation of sand dunes, and the pressure drop value was related to the axial position of sand dunes.…”