Anais do Simpósio Nacional de Bioprocessos
XXII National Bioprocesses Symposium (SINAFERM) XIII Enzymatic Hydrolysis of Biomass Symposium (SHEB)

Microalgae cultivation may differ in numerous parameters, which implies in different photobioreactor configurations for each purpose. The objective of this work was to evaluate the cultivation of a high CO2-tolerant microalga using two closed photobioreactor configurations, one with continuous aeration (with air enriched with 5% CO2) and another with non-continuous (intermittent) aeration, as the bioreactor was filled once a day to guarantee the CO2 supply. Growth was directly monitored using pH and dissolved oxygen sensors and indirectly monitored with optical density measures, chlorophyll-a content, dry biomass concentration and elemental compositional analysis. Results demonstrated a very clear profile of O2 production over the light/dark cycles under continuous aeration, which was not observed under the intermittent operation mode. However, the experimental set-up with non-continuous CO2 supply provided similar kinetic parameters and CO2 fixation rates with reduced operational costs and it could be recommended especially in microalgae cultivations under increased CO2 concentrations.