[P008] Poster

1:00 PM - 1:50 PM JST(4:00 AM - 4:50 AM UTC)

[P04-590] Development of a Cost Effective Preindustrial Photobioreactor with Double Airlift Units for Scalable Microalgal Cultivation

○Jian Li¹, Spiros N. Agathos^1,2 (1. Harbin Engineering University (China), 2. Catholic University of Louvain (Belgium))

Keywords:

Microalgae,photobioreactor,Scale up,growth kinetics,Hydrodynamic chacterization

Microalgae offer a promising sustainable platform for biofuels nutraceuticals pigments and CO2 fixation However large scale production remains constrained by high capital and operational costs of conventional photobioreactors To address this a novel preindustrial scale photobioreactor featuring double airlift units was designed constructed and characterized based on the principle of minimum construction and operation costs The reactor utilizes two integrated airlift circulation loops that create robust liquid flow through differential gas holdup between riser and downcomer sections This configuration eliminates mechanical impellers significantly reducing energy consumption and shear stress on microalgal cells while ensuring efficient mixing CO2 supply O2 removal and beneficial light dark cycling for photosynthesis Hydrodynamic performance including gas holdup liquid circulation velocity and volumetric mass transfer coefficient was both mathematically modeled using fundamental fluid dynamics principles and experimentally validated The modeling results showed strong agreement with experimental data across various operating conditions confirming the reliability of the models for design optimization The reactor was thoroughly tested by cultivating representative microalgal strains under controlled indoor conditions as well as variable outdoor environments with natural solar irradiance Consistent biomass accumulation was achieved with growth rates comparable to or better than those in more expensive closed systems A comprehensive kinetic model incorporating light attenuation nutrient availability CO2 mass transfer and hydrodynamic effects was developed to describe cell growth dynamics and support future scale up predictions Strategies for scaling the system to industrial volumes were evaluated focusing on modular construction dynamic similarity and energy efficiency Technoeconomic analysis estimated capital and operational costs demonstrating substantial savings compared to traditional tubular or flat panel PBRs while maintaining competitive productivity In conclusion this double airlift photobioreactor successfully bridges laboratory research and commercial production The design offers a cost effective solution for large scale microalgal cultivation with strong potential to advance sustainable biomanufacturing and renewable bioresources Further pilot scale demonstrations are underway to accelerate industrial implementation