Flow regime transition and liquid distribution in a 3D cocurrent
downflow three-phase moving bed
- Shaoshuo Li,
- Yaohui Wang,
- Yao Yang,
- Zhengliang Huang,
- Jingyuan Sun,
- Zuwei Liao,
- Jingdai Wang,
- Yang Yongrong,
- Bing DU
Abstract
Based on a cold-flow experimental device, the transition between trickle
flow and pulse flow in a 3D cocurrent downflow three-phase moving bed is
investigated by the standard deviation of pressure drop and visual
observations. Results show that at a constant gas flow rate, the
trickle-to-pulse transition shifts to a higher liquid flow rate with the
increasing solid flow rate because the particle moving inhibits the
formation of local liquid blockage. Furthermore, an empirical model is
proposed to fit the trickle-to-pulse transition boundary by correlating
the dynamic liquid holdup at the boundary with the gas Reynolds number
and the particle velocity. Finally, the effects of the particle moving
on the liquid distribution is investigated, which show that the particle
moving makes the liquid distribution more uniform when the solid flow
rate is smaller than a certain value. But further increasing the solid
flow rate, the liquid distribution becomes uneven