Feasibility of Growing Chlorella sorokiniana on Cooking Cocoon Wastewater for Biomass Production and Nutrient Removal

The feasibility of microalgae cultivation using cooking cocoon wastewater (CCW) collected from a silk production factory was investigated in this work. Results showed that Chlorella sorokiniana grew well on the CCW whether it was autoclaved or not. After 7-day cultivation, the biomass increased by 1.57, 2.78, 3.33, and 3.14 times, and by 3.65, 4.03, 3.27, and 2.82 times when this alga was cultivated in the raw CCW (R-CCW) and autoclaved CCW (A-CCW) at the initial dry cell densities of 0.01, 0.04, 0.08, and 0.16 g/L, respectively. The algal photosynthetic growth was not affected when this alga grew on the R-CCW at an initial dry cell density of ≥ 0.04 g/L, while it was significantly inhibited when the initial dry cell density was 0.01 g/L. Additionally, this alga could remove nutrients rapidly from the CCW, and the removal efficiency increased with the increase of initial dry cell density. Thus, it was concluded that the CCW could be used as a good-quality medium for the algal growth, which is worthy of further study and promotion.