983684 - Modeling Mass and Momentum Transfer During Volatile Organic Compounds Adsorption on Honeycomb Structured Zeolite Adsorbent

Adsorption is a widely used technique to control the emissions of volatile organic compounds (VOC) from gas streams. Structured adsorbents, such as zeolite monoliths, have emerged as alternatives to more conventional morphologies (e.g. beads, granules, fibers, etc.) for fast cyclic adsorption-regeneration processes, due to their ability to achieve high mass and heat transfer and accommodate large flow rates with low pressure drop.
This study investigates mass and momentum transport in a honeycomb structured zeolite during dynamic adsorption of VOC using computational fluid dynamics simulation. Diffusion in both radial and axial directions was included for simulating the breakthrough profile. The Linear Driving Force (LDF) model was used for gas adsorption kinetics on the adsorbent.
The simulation results were validated using experimental adsorption breakthrough tests. It was noted that the shape of the simulated breakthrough profile is very sensitive to the effective mass transfer coefficient in the LDF model. The simulations results also indicated that the flow distribution has a greater influence compared to the axial diffusion on breakthrough time.
The developed model provided reliable predictions of the performance of the honeycomb structured zeolite under the targeted operating conditions, but also may be useful for increasing VOC removal efficiency through improved adsorber design and operation.