Abstract
This work describes the development of a microalga-mediated process for simultaneous removal of residual ammonium nitrogen (NH4+-N) and production of lipids from biologically treated coke effluent. Four species of green algae were tested using a sequential mixotrophic process. In the first phase-CO2-supplied mixotrophic condition-all microalgae assimilated NH4+-N with no evident inhibition. In second phase-volatile fatty acids (VFAs)-supplied mixotrophic condition-removal rates of NH4+-N and biomass significantly increased. Among the microalgae used, Arctic Chlorella sp. ArM0029B had the highest rate of NH4+-N removal (0.97mg/L/h) and fatty acid production (24.9mg/L/d) which were 3.6- and 2.1-fold higher than those observed under the CO2-supplied mixotrophic condition. Redundancy analysis (RDA) indicated that acetate and butyrate were decisive factors for increasing NH4+-N removal and fatty acid production. These results demonstrate that microalgae can be used in a sequential process for treatment of residual nitrogen after initial treatment of activated sludge.
Original language | English |
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Pages (from-to) | 488-495 |
Number of pages | 8 |
Journal | Bioresource Technology |
Volume | 191 |
DOIs | |
State | Published - 31 Mar 2015 |
Keywords
- Coke wastewater
- Microalgae
- Mixotrophic conditions
- Nitrogen removal
- Volatile fatty acid (VFA)