Synergistic effect of microbubble flow and light fields on a bionic tree- like photobioreactor

A bionic fractal tree-like photobioreactor (PBR) with multiscale bubbles was studied to help intensify gas-liquid mass transfer and the microalgal photosynthesis. A numerical simulation and several experiments were conducted to study the hydrodynamic characteristics of the microbubbles (MBs) and large bubbles (LBs) in the tree-like PBR. The characteristics studied included the bubble size distribution, flow pattern, gas holdup, gas-liquid slip ratio, and turbulence. The good flow characteristic of the MBs tended to generate a homogeneous dispersed flow pattern, which intensified the synergistic effect of flow and light fields based on the long residence time, large gas-liquid contact area, and even multiphase mixing in the large-area illuminated fractal reactor. As a result, the photosynthetic capacity and microalgal activity were enhanced by combining the tree-like PBR with MBs, providing a novel valuable technical solution for improving the multiphase photoreaction. (c) 2020 Elsevier Ltd. All rights reserved.

Automated summary

A bionic fractal tree-like photobioreactor with multiscale bubbles was studied to enhance gas-liquid mass transfer and microalgal photosynthesis. Numerical simulations and experiments focused on characteristics of microbubbles and large bubbles in the reactor, finding that the good flow characteristic of microbubbles tended to generate a homogeneous dispersed flow pattern. Combining the tree-like PBR with microbubbles enhanced photosynthetic capacity and microalgal activity, providing a novel technical solution for improving multiphase photoreaction.