Photoautotrophic Microalgal Cultivation and Conversion

Abstract

As the largest photoautotrophic microorganisms communities, microalgae are important materials for biological carbon dioxide fixation through photosynthesis and biodiesel production due to their fast growth rate, significant carbon dioxide capture capacity, high lipid content, etc. They are also regarded as the promising feedstocks for the third-generation biofuels. For the cultivation of microalgae, photobioreactors (PBRs) are necessary apparatuses that provide appropriate growth conditions for the proliferation of microalgal cells. Nevertheless, the design of an efficient PBR is associated with many thermodynamic challenges, such as light, CO2, and inorganic nutrients transfer in microalgal culture, all of which have a significant impact on the performance of the PBR. Up to now, various attempts have been devoted to optimize the light distribution, CO2, and nutrients transfer within microalgal cultures that employ light-guiding materials, hollow fiber membranes, anion exchange membranes, etc. In this chapter, we provided an overview and generated a comprehensive comparison on PBR performance enhancement methods from the perspectives of light and mass transfer, as well as potential approaches for the concentrating and conversion of photoautotrophic microalgal cells to biofuels.