A gas-liquid-solid inverse  uidization airlift bioreactor was proposed by combining advantages of external-loop airlift reactors and inverse  uidized beds. This airlift bioreactor comprises a gas-liquid riser, a gas separator, a liquid-solid inverse  uidized downcomer and a bottom connector. The effects of the gas velocity and the particle loading on the gas holdup in the riser and the liqui...

In this work, CFD simulations of an air-water bubbling column were performed and validated with experimental data. The superficial gas velocities used for the experiments were 0.019 and 0.038 m/s and were considered as an homogeneous regime. The former involves simpler physics when compared to a heterogeneous regime where the superficial velocities are higher. In order to simulate the system, a...

In the gas-water two phase of horizontal well, gas holdup is usually obtained by inverse calculation water measured array capacitance probes. Gas Array Tool (GAT) has been developed to directly measure holdup. This instrument introduced into China and its simulation experiment in flow wells carried out for first time study applicability measurement. Firstly, response principle measurement metho...

Abstract The gas-liquid-solid mixing characteristics in slurry bubble column were studied using the CFD-PBM model under different cross section coverage ratios of tubes. research shows that with increase proportion area vertical tube, flow field tends to be stable, liquid phase rate becomes faster, and large-scale circulation strengthens, resulting decrease gas holdup. As increases, distributio...

Fluidized beds can be used to gasify biomass in the production of producer gas, a flammable gas that can replace natural gas in process heating. Modeling these reactors with computational fluid dynamics (CFD) simulations is advantageous when performing parametric studies for design and scale-up. From a computational resource point of view, two-dimensional simulations are easier to perform than ...

Numerical simulations of the small bubble-big bubble-liquid three phase heterogeneous flow in a square cross-sectioned bubble column were carried out with the commercial CFD package CFX-4.4 to explore the effect of superficial velocity and inlet dispersed phase fractions on the flow patterns. The approach of Krishna et al. (2000) was adopted in the Euler-Euler framework to numerically simulate ...

The hydrodynamic parameters were determined for two different three-phase systems (fluidized-bed and trickle-bed) through the experimental evaluation of the dynamic residence time distribution in the gas or liquid phase. For different fluid phase flow rates the fluidized-bed system was operated with a tracer in the gas phase and in the trickle-bed with a tracer in the liquid phase. The analysis...