(480c) A Growth Model for Chlorella vulgaris Including Photolimitation and Photoinhibition Effects

Light is an essential source for the autotrophic growth of microalgae.  The distribution of light in the reactor decreases when microalgae grow as a result of the shading effect known as photolimitation.  In addition, the specific growth rate can decrease when the incident light intensity increases because high light can inhibit the growth rate of microalgae known as photoinhibition.  These two effects should be taken into account for developing a growth model for microalgal cultivation.  In previous studies, light growth models were developed by adding the shading effect.  But, a light growth model taking into account these two effects has not been developed.  In this study, a growth model of Chlorella vulgaris was developed by taking into consideration both the photolimitation and photoinbition effects.  The model was applied to estimate the growth of Chlorella vulgaris with respect to incident light intensities and reactor sizes and was compared with the experimental data.  The modeling results were in good agreement with the experimental data.  The model is expected to be used to estimate the autotrophic growth of Chlorella vulgaris for various reactor types by incorporating hydrodynamics into the light growth model.