Effect of Light Irradiance on Growth and Lipid Content of Microalgae Chlorella Vulgaris in a Flat Panel Photobioreactor
Volume Title: 1
1School of Chemical Engineering
2School of Chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran
Light has an incredible effect on microalgal growth, and the self-shading of microalgal cells reduces light penetration. In this study, Chlorella vulgaris was cultivated in a flat panel PBR, and the effect of light path and biomass concentration (C= 0.142 - 1.7 g L-1) on light attenuation inside the PBR was investigated and discussed. The results showed that with an increase in biomass concentration, light intensity decreased sharply, especially in regions 2-4 cm from the light incident surface, which suggested that flat-panel PBRs be constructed with < 4 cm width. Also, when biomass concentration was 1.7 g L-1, light intensity decreased 92% over the first 2 cm. However, when biomass concentration was 0.142 g L-1, light intensity only falls 57%. The optimum biomass concentration was 1 g L-1 to avoid having lower-than optimum light intensity inside the PBR and, also, to have the highest lipid production rate.