Format

Send to

Choose Destination
J Ind Microbiol Biotechnol. 2010 Dec;37(12):1319-26. doi: 10.1007/s10295-010-0876-5. Epub 2010 Nov 18.

Experimental validation of a nonequilibrium model of CO₂ fluxes between gas, liquid medium, and algae in a flat-panel photobioreactor.

Author information

1
Institute of Systems Biology and Ecology ASCR, Zámek 136, 37333 Nové Hrady, Czech Republic. nedbal@greentech.cz

Abstract

Carbon dioxide (CO₂) availability strongly affects the productivity of algal photobioreactors, where it is dynamically exchanged between different compartments, phases, and chemical forms. To understand the underlying processes, we constructed a nonequilibrium mathematical model of CO₂ dynamics in a flat-panel algal photobioreactor. The model includes mass transfer to the algal suspension from a stream of bubbles of CO₂-enriched air and from the photobioreactor headspace. Also included are the hydration of dissolved CO₂ to bicarbonate ion (HCO₃⁻) as well as uptake and/or cycling of these two chemical forms by the cells. The model was validated in experiments using a laboratory-scale flat-panel photobioreactor that controls light, temperature, and pH and where the concentration of dissolved CO₂, and partial pressure of CO₂ in the photobioreactor exhaust are measured. First, the model prediction was compared with measured CO₂ dynamics that occurred in response to a stepwise change in the CO₂ partial pressure in the gas sparger. Furthermore, the model was used to predict CO₂ dynamics in photobioreactors with unicellular, nitrogen-fixing cyanobacterium Cyanothece sp. The metabolism changes dramatically during a day, and the distribution of CO₂ is expected to exhibit a pronounced diurnal modulation that significantly deviates from chemical equilibrium.

PMID:
21086107
DOI:
10.1007/s10295-010-0876-5
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Springer
Loading ...
Support Center