Wastewater Treatment by Microalgae under Light/Dark Cycles

초록

C. kessleri was cultivated in an artificial wastewater under diurnal illumination of 14 h light/10 h dark cycles. Regardless of illumination scheme, the culture reduces TOC and COD by a comparable amount. However, cell concentration under light/dark cycles was lower than continuous illumination culture. Thus the specific removal rate of organic carbon under light/dark cycles was higher than that of continuous illumination culture. This results suggested that C. kessleri grew chemoorganotrophically in the dark periods. To maximize the consumption of organic compounds, light/dark ratio needs to be determined. High-density algal cultures using optimized photobioreactors with L/D cycles will improve the removal rate of eutrophic nutrients significantly.