Liquid Phase Dispersion/Mixing Investigation in Gas-liquid Upflow Moving
Bed Hydrotreater Reactor(MBR)
Abstract
Liquid phase dispersion/mixing studies have been performed for the first
time on the catalyst bed of a cold flow scaled-down upflow moving bed
re- actor (MBR) using residence time distribution (RTD) at various flow
rates including the scaled down condition. MBR is hydrotreater and its
design includes catalyst bed with conical bottom and plena. The catalyst
bed is modeled using Wave Model, and its mixing parameters are estimated
using a mathematical approach based on convolution and regression. A
study is also shown to illustrate the limitation of Axial Dispersion
Model (ADM) while modeling the flow which noticeably deviates from plug
flow. In addition, a dimensionless variance is also estimated for the
bed region from the RTDs. Overall liquid dispersion/mixing is seen high
in MBR, with more disper- sion/mixing in the expanded bed region. Scaled
down conditions are seen best when considering the overall catalyst
utilization and liquid mixing for hydrotreatment.