Numerical simulation of baffled circulating fluidized bed with Geldart B particles

TL;DR

This study uses CFD simulations to analyze how ring baffle configurations affect the hydrodynamics of circulating fluidized beds, aiming to improve mixing and reduce backflow.

Contribution

It introduces a multifluid Eulerian CFD model with granular flow theory to compare circular and trapezoidal baffles in CFB reactors.

Findings

Ring baffles improve system mixing.

Baffles reduce backflow near the wall.

Shape of baffles has limited impact.

Abstract

As most classical fluidization technologies, Circulating Fluidized Beds (CFB) are widely employed in chemical and physical operations. However, CFB Reactors still have some disadvantages such as the non-uniform solid particles distribution and the backflow of the solid particles near the wall, which deteriorate the system mixing, and lead to low system conversion/heat and mass transfer rate. To improve the CFB performance, we propose in the current work to study the effect of the ring baffle configuration on the fluidization system hydrodynamics using a multifluid Eulerian CFD model, incorporating the Kinetic Theory of Granular Flow. In this approach, two different types of ring baffles, circular and trapezoidal, were considered and the corresponding results were compared. The results revealed that the incorporation of ring baffles improved the system mixing and reduced the backflow near the wall. Nevertheless, the shape of baffles had a limited impact on the system hydrodynamics.