Modelling growth and CO2 fixation by Scenedesmus vacuolatus in continuous culture

Abstract

A screening of eight species of microalgae and cyanobacteria in continuous culture was performed  Scenedesmus vacuolatus was selected for modelling its growth and CO 2 fixation  The potential of this microalga for carbon abatement was tested using simulated flue gas as the source of CO 2 .

How to combine CO2 abatement and starch production in Chlorella vulgaris

“…The growth model presented in this research represents a comprehensive approach, as it includes five different culture parameters, achieving a good fit to the experimental data (R 2 = 0.95). Like other growth models for species as Scenedesmus or Nannochloropsis, our results confirmed that irradiance and temperature are the main parameters that affect the microalgal performance [14,41], followed by nitrogen supply and pH. The growth model allowed us to combine the optimum culture parameters that resulted in maximum yields.…”

“…Moreover, starch accumulation during this optimization was determined and used to generate a model to predict the pattern of starch accumulation in CO 2 abatement process. The optimization process of this model followed the same approach as the previous model, i.e., "single parameter optimization" [14].…”

“…Other operational regimes such as batch or semi-continuous have been tested for this microalga in other studies but rendering lower yields (0.3 g L −1 d −1 ) [38]. Regarding other microalgal species cultivated photo-autotrophically in continuous fed as Scenedesmus, Chlorococcum or Pseudokirchneriella [14,39], Chlorella might be defined as a fast growing and efficient CO 2 assimilation microorganism. Considering our data, C. vulgaris might be a candidate for a fast turn-over process thanks to its capability of adapting its growth to fast dilution rates.…”

“…The incident irradiance on reactor's surface was also evaluated. We tested a range of light intensities that embraced the maximum irradiances that typically can be found outdoors at different locations and/ or environmental situations (from low intensities typically found in northern latitudes, 1000 mol PAR m −2 s −1 to extremely high light intensities found in more meridional locations, 3000 mol PAR m −2 s −1 ) [14,34,40]. However, as San Pedro et al showed [41], the effect of light might be considered as light availability (I av ) and not just as the light irradiance that impinges on the reactor's surface.…”

“…For this reason, the development of growth models is a promising tool to understand and increase the yields of the cultures. Among possible strategies for developing models, the "single parameter optimization" approach was selected based on our previous work [14]. The main goal of the present research was to maximize and model biomass productivity and CO 2 assimilation in continuous cultures of Chlorella vulgaris.…”