Abstract
Light and carbon dioxide provision are vital for microalgae growth in photoautotrophic cultivation processes. For improving lighting conditions of photobioreactors, internal LED lighting has gained interest in enhancing photobioreactor conditions. Fixing CO2 by algae cultivation has been extensively studied for various applications. This study uses Computational Fluid Dynamics to compare a range of cylindrical vessels as setups for algae cultivation, evaluating their effect on illumination and CO2 distribution in the reactor, and consequently on bioproductivity of the microalgae Chlorella vulgaris. Small, CO2 enriched gas bubbles were applied for providing CO2 into the broth and larger bubbles of atmospheric air for mixing the solution. Internal illumination was introduced by eight LED rods. Three geometries of laboratory scale reactors were investigated with two different gas feeding areas and one elongated vessel. The modeling results for bioproductivity were compared to an outer surface illumination and mechanical stirrer for mixing, with CO2 enriched gas in-feed with CO2 concentration of 2.5 % (v/v). The process conditions for lighting, the total CO2 in-feed concentration, and the total in-feed gas rate were kept comparable between the investigated cases. Improved algal bioproductivity of Chlorella vulgaris was observed in cases with internal light provision due to more uniform illumination.
| Original language | English |
|---|---|
| Article number | 104209 |
| Journal | Algal Research |
| Volume | 91 |
| DOIs | |
| Publication status | Published - Oct 2025 |
| MoE publication type | A1 Journal article-refereed |
Funding
This work has received funding from the European Union – NextGenerationEU instrument and is funded by the Academy of Finland under grant number 353023 and by Business Finland with grant number 6563/31/2021.