title: Optimizing carbon dioxide utilization for microalgae biofilm cultivation.
abstract: The loss of carbon dioxide (CO2) to the environment during microalgae cultivation is undesirable for both environmental and economic reasons. In this study, a phototrophic biofilm growth model was developed and validated with the objective to maximize both CO2utilization efficiency and production of microalgae in biofilms. The model was validated in growth experiments with CO2as the limiting substrate. The CO2utilization and biomass productivity were maximized by changing the gas flow rate, the number of biofilm reactors in series and gas composition. Based on simulations, the maximum CO2utilization efficiency that was reached was 96% based on a process employing flue gas. The corresponding drop in productivity was only 2% in comparison to the non-CO2limited reference situation. In order to achieve this, 25 biofilm reactors units, or more, must be operated in series. Based on these results, it was concluded that concentrated CO2streams and plug flow behavior of the gaseous phase over the biofilm surface are essential for high productivity and CO2utilization efficiency. Biotechnol. Bioeng. 2017;114: 769-776. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Bioprocess Engineering, AlgaePARC, Wageningen University, PO Box 16, 6700 AA, Wageningen, The Netherlands.
authors.forename: Ward
authors.initials: W
authors.lastname: Blanken
authors.affiliation: Bioprocess Engineering, AlgaePARC, Wageningen University, PO Box 16, 6700 AA, Wageningen, The Netherlands.
authors.forename: Stefan
authors.initials: S
authors.lastname: Schaap
authors.affiliation: Bioprocess Engineering, AlgaePARC, Wageningen University, PO Box 16, 6700 AA, Wageningen, The Netherlands.
authors.forename: Sophie
authors.initials: S
authors.lastname: Theobald
authors.affiliation: Bioprocess Engineering, AlgaePARC, Wageningen University, PO Box 16, 6700 AA, Wageningen, The Netherlands.
authors.forename: Arjen
authors.initials: A
authors.lastname: Rinzema
authors.affiliation: Bioprocess Engineering, AlgaePARC, Wageningen University, PO Box 16, 6700 AA, Wageningen, The Netherlands.|Faculty of Biosciences and Aquaculture, Nord University, N-8049, Bodø, Norway.
authors.forename: René H
authors.initials: RH
authors.lastname: Wijffels
authors.affiliation: Faculty of Biosciences and Aquaculture, Nord University, N-8049, Bodø, Norway.
authors.forename: Marcel
authors.initials: M
authors.lastname: Janssen
mesh_terms: D018441:Biofilms; D018533:Biomass; D002245:Carbon Dioxide / Q000378:metabolism*; D058086:Microalgae / Q000378:metabolism*; D008954:Models, Biological; D058433:Photobioreactors; D015203:Reproducibility of Results
chemical_list: D002245:Carbon Dioxide
keywords: CO2 utilization efficiency; biomass productivit; carbon dioxide; microalgal biofilm; microalgal growth model