A modelling workflow for quantification of photobioreactor performance
Wenjia Gu, Emile Theau, A. Anderson, David F. Fletcher, John M. Kavanagh, Dale D. McClure
Abstract
• Comprehensive workflow for PBR modelling developed. • CFD model validated against comprehensive experimental data-set. • Best designs and operating conditions examined give 40% improvement in productivity. • Modelling workflow can be used for in silico design of photobioreactors. In this work we have developed a comprehensive modelling workflow for the quantification of photobioreactor performance. Computational Fluid Dynamics (CFD) modelling combined with Lagrangian particle tracking was used to characterise the flow field inside the reactor; this information was combined with a Monte-Carlo model of light attenuation and a kinetic growth model to predict the performance of the system over the duration of the entire batch. The CFD model was validated against measurements of the overall hold-up, local hold-up and mixing time for superficial velocities between 0.6 and 6 cm s −1 in a pilot-scale bubble column photobioreactor, with the CFD predictions agreeing with the experimental data. Comparison was also made between the predicted biomass concentration and experimental measurements using the diatom Phaeodactylum tricornutum , with the model predictions being in good agreement with the experimental results. The model was used to investigate a range of operating conditions and reactor designs, with the most promising predicted to give a 40 % increase in the biomass productivity. Results from this work can be used for the in-silico design and optimisation of photobioreactor systems, thereby enabling their wider use as a sustainable production technology.