Flow behavior and size characteristics of microbubble swarm in a HiGee-aided fixed bed reactor with different packed structures

Abstract

A HiGee-aided fixed bed reactor (HFBR) has great potential for catalytic hydrogenation with hydrogen microbubble swarm for gas–liquid mass transfer intensification. However, the flow behavior and size characteristics of microbubble swarm in the catalyst bed of HFBR still remain unclear. In this work, the flow characteristics of microbubble swarm in different packed structures of catalysts and catalyst supports had been fully analyzed by the high-speed photography and image processing technology. The optimal ratio of packing heights for the bottom of the catalyst supports was Φ13 mm: Φ6 mm: Φ3 mm = 3: 1: 1, while the top of the catalyst supports was packed with single catalyst support of Φ6 mm. Furthermore, a dimensionless correlation based on the experimental results had been developed to predict (d32)o/(d32)i with deviations within ±15 %. The effective interfacial area of HFBR was 0.6 ∼ 6.1 × 103 m2/m3 under the experimental conditions.