Industrial & Engineering Chemistry Research, Vol.59, No.44, 19712-19725, 2020
Fluid Dynamics Scaling of a Gas-Liquid Distributor Applied to a Commercial Ebullated Bed Hydroprocessor
A new scaling approach for a gas-liquid distributor is proposed and experimentally validated on a commercial bubble cap geometry. The geometric similarity was achieved by matching distributor fractional opening and ratios of various critical dimensions. The dynamic similarity was attained by matching three dimensionless groups (gas-liquid density ratio, liquid Reynolds number, and gas Froude number) and bubble coalescence behavior. Two geometrically similar distributors with one and three smaller bubble caps were experimentally compared through resulting bubble size distributions to test the scaling laws. A reasonably good agreement was found at various pressures, suggesting that the scaling approach could also work at industrially relevant conditions. New models for bubble size distribution and drag coefficient were developed to explicitly account for the effect of the gas-liquid distributor and thus improve the fluid dynamics modeling of commercial ebullated bed hydroprocessors.