# Modeling CO2 Adsorption in a Thin Discrete Packing

## TL;DR

This paper models CO2 adsorption in a thin tube packing to improve understanding of transport mechanisms in energy storage and air revitalization systems.

## Contribution

The study reveals that diffusive transport dominates over advective transport in CO2 adsorption within thin discrete packings.

## Key findings

- CO2 concentration gradients are significant at both inter- and intraparticle scales.
- Convective transport increases in areas of solid particles exposed to high gas velocities.
- Modeling results align with experimental data, reducing the need for empirical dispersion models.

## Abstract

Local dynamics of
CO2 adsorption in a discrete packing
contained in a thin tube was assessed by 3D modeling. Thin tube packed
bed adsorbers are currently used over tube structures in thermochemical
energy storage systems and atmospheric revitalization of confined
spaces. Driven by the interplay between key factors such as the exothermicity
and the fluid flow, the advective transport was found less effective
than the diffusive one on the breakthrough trends of CO2 which displayed significant concentration gradients at both inter-
and intraparticle scales. The lack of angular symmetry inside the
particles by the reduction in resistance to mass transfer in the area
of solid particles exposed to high velocities led to greater convective
transports from the bulk of the gaseous phase to the pores. The result
of the modeling agreed with the experimental data obtained at the
exit of the adsorber, helping reduction in reliance on the empirical
dispersion models used in the one-dimensional modeling.