Tube wear in gas fluidized beds—I. Experimental findings

doi:10.1016/0009-2509(90)85021-5

Chemical Engineering Science

Volume 45, Issue 4, 1990, Pages 1003-1015

https://doi.org/10.1016/0009-2509(90)85021-5 Get rights and content

Abstract

Rates of materials loss for horizontal tubes were determined by accurately weighing small rings or ring segments after exposure to fluidized particles under room temperature conditions in a column of cross-section 203 × 216 mm. Wear was found to increase with increasing void velocity, particle size and particle angularity, and with decreasing tube diameter. Most metal loss occurred around the bottom of the tube and in the central part of the column for the near slugging conditions prevailing in the column. The presence of neighbouring tubes led to a reduction in net wear and a change in its spatial distribution. A tube located in the distributor zone showed increased wear. Young's modulus appears to be the major tube material property affecting the rate of wear, except for tubes of very low hardness. Particle impacts appear to be much more important than abrasion. Incubation periods were too short to be of much importance in practical fluidized-bed processes.

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Tube wear in gas fluidized beds—I. Experimental findings

Abstract

Chem. Engng Sci.

Chem. Engng Sci.

Wear

Flow regimes and void fraction distribution in gas fluidization of large particles in beds with tube banks

A.I.Ch.E. Symp. Ser.

Continuous bubbling and slugging

Scaling the hydrodynamics of fluidized bed combustors with cold models: experimental confirmation

The distribution of bubbles within a gas fluidized bed

Instn chem. Engrs Symp. Ser.

Fluidized beds with internal baffles