Partic. vol. 19 pp. 173-184 (April 2015)
doi: 10.1016/j.partic.2014.05.011

Anti-wear beam effects on gas–solid hydrodynamics in a circulating fluidized bed

Yunfei Xia, Leming Cheng^* , Chunjiang Yu, Linjie Xu, Qinhui Wang, Mengxiang Fang

lemingc@zju.edu.cn

Abstract

Anti-wear beams installed on water walls of circulating fluidized bed (CFB) boilers are one of the most effective ways to protect against water-wall erosion. Beam effects from, for example, beam size and superficial gas velocity were investigated on gas–solid hydrodynamics in a CFB test rig using CFD simulations and experimental methods. The downward flow of the wall layer solids is observed to be disrupted by the beam but is then restored some distance further downstream. When falling solids from the wall layer hit the anti-wear beam, the velocity of the falling solids decreases rapidly. A fraction of the solids accumulates on the beam. Below the beams, the falling solids have reduced velocities but upward-moving solids were observed on the wall. The effect of the beam increases with width and superficial gas velocity. Wear occurs mainly above the beam and its variation with width is different above to below the beam. There is an optimum width that, when combined with beam height, results in less erosion.

Graphical abstract

Keywords

Circulating fluidized bed; Gas–solid hydrodynamics; Anti-wear beam