Tube wear in gas fluidized beds—I. Experimental findings

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.