Modelling microalgae growth in nitrogen limited photobiorector for estimating biomass, carbohydrate and neutral lipid productivities

International audienceMicroalgae culture for energy production has emerged as an interesting alternative to fossil fuel and biofuel from terrestrial plants. In this paper, we propose a dynamical model of microalgae growth in photobioreactor in order to further optimize productivity. We consider light and nitrogen effects on microalgae growth and on the intracellular carbon flows between a functional compartment (proteins, nucleic acids, membranes) and two storage pools (carbohydrates and neutral lipids). In a second step, we take into account the photoacclimation dynamics. We also compute the light distribution inside the photobioreactor using a Beer-Lambert law. The proposed model has been assessed with experimental data of Isochrysis affinis galbana under day/night cycles. Finally, the model is used to predict carbohydrate, neutral lipid, and biomass productivities and to identify optimal operating conditions (dilution rate and influent nitrogen concentration)