This study reports an investigation of the concept, application and performance of a novel bioelectrochemical nitritation-anammox microbial desalination cell (MDC) for resource-efficient wastewater treatment and desalination. Two configurations of anammox MDCs (anaerobic-anammox cathode MDC (AnAmoxMDC) and nitration-anammox cathode MDC (NiAmoxMDC)) were compared with an air cathode MDC (CMDC), operated in fed-batch mode. Results from this study showed that the maximum power density produced by NiAmoxMDC (1,007 mW/m3) was higher than that of AnAmoxMDC (444 mW/m3) and CMDC (952 mW/m3). More than 92% of ammonium-nitrogen (NH4+-N) removal was achieved in NiAmoxMDC, significantly higher than AnAmoxMDC (84%) and CMDC (77%). The NiAmoxMDC performed better than CMDC and AnAmoxMDC in terms of power density, COD removal and salt removal in desalination chamber. In addition, cyclic voltammetry analysis of anammox cathode showed a redox peak centered at −140 mV Vs Ag/AgCl confirming the catalytic activity of anammox bacteria towards the electron transfer process. Further, net energy balance of the NiAmoxMDC was the highest (NiAmoxMDC-0.022 kWh/m3>CMDC-0.019 kWh/m3>AnAmoxMDC-0.021 kWh/m3) among the three configurations. This study demonstrated, for the first time, a N-E-W synergy for resource-efficient wastewater treatment using nitritation-anammox process.
- Award ID(s):
- 1632019
- NSF-PAR ID:
- 10080558
- Date Published:
- Journal Name:
- Chemical engineering journal
- Volume:
- 342
- ISSN:
- 1385-8947
- Page Range / eLocation ID:
- 410-419
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract -
Senko, John M. (Ed.)
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Practitioner points Primary sludge fermentate was evaluated as an alternative carbon source for mainstream partial denitrification–anammox (PdNA).
Fermenter operated at a 1 to 2 day SRT resulted in the maximum achievable yield without the release of excessive ammonia and phosphorus to the system.
Although 93% partial denitrification efficiency was achieved with fermentate in batch experiments, around 49% PdN efficiency was achieved in pilot studies.
Application of PdNA with fermentate can result in significant methanol cost savings.
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