Visualization Experimental Study on Starting Process of the Absorber Sphere Pneumatic Conveying

Visualization experiments were conducted in a positive pressure system to investigate the starting process characteristics of the absorber sphere pneumatic conveying. The ambient air was used as the source gas. The absorber sphere was replaced by the glass sphere. Spouted spheres flow was observed at the early stage of the starting process. With the increase of feeder inlet gas flow rate with time after starting the blower, the amount of fluidized spheres in the riser pipe first increased gradually and then decreased to the steady conveying state. The steady conveying was achieved as the feeder inlet gas flow rate was up to the maximum. A peak pressure was observed at the feeder gas inlet. The sphere blown away pressure was approximately 20 kPa higher than the steady conveying pressure. The time lasted for the pressure higher than the steady conveying pressure was about 10 s. The process for spheres blown away at the early stage of the starting process was more difficult than the steady conveying. The pressure increase and the duration characteristics should be taken into account for the blower pressure parameters design in the practical engineering application.