Effect of optical panel thickness for nutrient removal and cultivation of microalgae in the photobioreactor

The aim of this study was to quantitatively evaluate the effect of the illumination area and the thickness of the optical panel (OP) on the biomass growth of Chlorella vulgaris (C. vulgaris) algae with simultaneous removal of nutrients. For this purpose, three different thicknesses of OPs were used and designated as follows: 4 mm v-cut OP (Run 1), 6 mm v-cut OP (Run 2) and 8 mm v-cut OP (Run 3). The results indicated that the Run 2 and Run 3 samples possessed higher chlorophyll content, as calculated per cell and per unit area of the cell volume, and a shorter doubling time compared to the Run 1 samples. The growth of the biomass using Run 2 and Run 3 was approximately 11.18 %, and this growth was higher than that of Run 1. Furthermore, higher nutrient removal was observed with Run 2 than Run 1. The nutrient removal, biomass growth and specific growth rate for the Run 2 and Run 3 fractions were found to be almost identical. However, in terms of economic consideration, Run 2 with simultaneous nutrient removal was more effective than Run 1 and Run 3 in cultivating the microalgae C. vulgaris.