Journal of Chemical Technology and Biotechnology, Vol.95, No.6, 1717-1728, 2020
Contribution of glycerol addition and algal-bacterial cooperation to nutrients recovery: a study on the mechanisms of microalgae-based wastewater remediation
BACKGROUND Microalgae biotechnology is considered as a promising way to recover nutrients from centrate wastewater for value-added biomass production, but it is rarely adopted in a real-world application. Current study confirmed that carbon deficiency and suspended solids are two problems jeopardizing the microalgae-based wastewater remediation. In this regard, glycerol was added into centrate wastewater as exogenous carbon source and algal-bacterial cooperation for nutrients recovery assessment. RESULTS The results showed that glycerol addition increased the biomass yield of algae from 1.54 to 2.58 g L-1 in 5-day culture and, at the same time, improved the removal efficiency of nitrogen and phosphorus, which were further assessed by pilot-scale experiments. Bacterial community analysis indicated that algal-bacterial cooperation involves carbon dioxide and oxygen exchange, phosphorus absorption, and solid organics degradation, forming a complementary nexus beneficial for wastewater treatment. CONCLUSION Glycerol is proven to be a good carbon source for microalgae growth in the centrate wastewater. Additionally, the cooperation between microalgae and bacteria plays a key role in the nutrients removal during centrate wastewater. It is expected the technology and knowledge provided by current work can further promote the industrialization of microalgae-based wastewater remediation. (c) 2020 Society of Chemical Industry