Residence time of a large heavy object in a fluidized bed with an uneven air distribution

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Abstract

The influence of the superficial gas velocity on the residence time distributions (RTDs) of large spherical objects of different densities in the dense phase of a fluidized bed was studied using electrical capacitance tomography (ECT) tracing technique. The regularity and randomness of the motion of a large object were decided by a probabilistic statistical analysis to investigate the mechanical characteristics of an object in a bed. The results show that decreasing the fluidization velocity first slowly reduces the residence time. When the gas velocity is lower than a critical value, the residence time sharply increases until the object does not reach the low side of the air distributor. Heavier objects have higher critical gas velocities. The RTD curves are very broad due to the stochastic pressure and velocity pulsations in the fluidization bed.

Keywords fluidized bed large heavy object residence time uneven air distribution probability distribution

Issue Date: 15 June 2014

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	Rongrong CAI
	Yanguo ZHANG
	Chenwei MENG
	Qinghai LI
	Aihong MENG

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Rongrong CAI,Yanguo ZHANG,Chenwei MENG, et al. Residence time of a large heavy object in a fluidized bed with an uneven air distribution[J]. Journal of Tsinghua University(Science and Technology), 2014, 54(6): 775-780.

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http://jst.tsinghuajournals.com/EN/ OR http://jst.tsinghuajournals.com/EN/Y2014/V54/I6/775

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