Cultivation of cyanobacterium in various types of photobioreactors for biological CO2 fixation

Abstract

Synechococcus sp. PCC6301 was cultivated in various types of enclosed photobioreactors for biological CO2 fixation. In order to maximize the photosynthetic efficiency of the cell, major culture conditions such as inlet CO2 concentration, incident light intensity, aeration rate, temperature, and agitation speed were optimized. To investigate the effects of bioreactor configuration on cell growth and CO2 fixation rate, we constructed stirred-tank photobioreactor (ST-PBR), florescent-lamp photobioreactor (FL-PBR), optical-filer photobioreactor (OF-PBR) and florescent-lamp/optical-fiber photobioreactor (FLOF-PBR). FL-PBR was found to be most energy efficient, whereas the highest CO2 fixation rate was obtained in the FLOF-PBR system. It is expected that the latter type of photobioreactor is useful for high-density cultivation of photosynethetic microorganisms and biological CO2 fixation in a large scale.