A strategy for urban outdoor production of high-concentration algal biomass for green biorefining
Lim, Chun Yong
Date of Issue2013
School of Civil and Environmental Engineering
Residues and Resource Reclamation Centre
The present study was to investigate the feasibility of carrying out effective microalgae cultivation and high-rate tertiary wastewater treatment simultaneously in a vertical sequencing batch photobioreactor with small areal footprint, suitable for sustainable urban microalgae production. For 15 consecutive days, Chlorella sorokiniana was cultivated in synthetic wastewater under various trophic conditions. A cycle of 12-h heterotrophic: 12-h mixotrophic condition produced 0.98 g l−1 d−1 of algal biomass in tandem with a 94.7% removal of 254.4 mg l−1 C-acetate, a 100% removal of 84.7 mg l−1 N-NH4 and a removal of 15.0 mg l−1 P-PO4. The cells were harvested via cost-effective chitosan flocculation with multiple dosing (3 times) applying established chitosan:cell ratio (1:300 w/w) and pH control (6.3–6.8). Reproducible flocculation efficiencies of greater than 99% and high-concentration algal broths (>20% solids) were achieved.
DRNTU::Engineering::Environmental engineering::Water treatment