To improve nutrients removal from real centrate wastewater and enhance the microalgae biomass production, cultivation of Chlorella vulgaris in lab and a pilot-scale photobioreactor with waste glycerol was studied. The results showed the optimal concentration of the crude glycerol was 1.0 g L−1 with the maximum biomass productivity of 460 mg L−1 d−1 TVS, the maximum lipid content of 27%, the nutrient removal efficiency of all above 86%, due to more balanced C/N ratio. The synergistic relationship between the wastewater-borne bacteria and the microalgae had significant good influence on nutrient removal. In pilot-scale wastewater-based algae cultivation, with 1 g L−1 waste glycerol addition, the average biomass production of 16.7 g m−2 d−1, lipid content of 23.6%, and the removal of 2.4 g m−2 d−1 NH4+-N, 2.7 g m−2 d−1 total nitrogen, 3.0 g m−2 d−1 total phosphorous, and 103.0 g m−2 d−1 of COD were attained for 34 days semi-continuous mode.
Bibliographical noteFunding Information:
Funding for this project was provided in part by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR) and University of Minnesota Center for Biorefining .
© 2017 Elsevier Ltd
- Centrate wastewater
- Nutrient removal
- Pilot-scale photobioreactor
- Waste glycerol