The solids flow in the CFB-riser quantified by single radioactive particle tracking

摘要: Single radioactive particle tracking was used to measure the overall solids residence time (and its distribution) in riser of a CFB, operating at superficial air velocities (U) 1 9 ms− and circulation fluxes (G) between 20 600 kg m− 2s− 1. The results demonstrate that motion mixing differ according mode riser, with fairly constant velocity throughout achieved dilute or dense flow, but significant amount back-mixing for intermediate values U and/or G. This is due core-annulus flow. Whereas experimental theoretical predictions are fair agreement regime needs account G dependent slip factor (φ), excess commonly proposed value φ = 2, especially U–UTR < 2 1. Moreover, previously published operation diagram confirmed by experiments, although further analysis needed.