Sustainable ammonia-contaminated wastewater treatment in heterotrophic nitrifying/denitrifying microbial fuel cell. (1st February 2020)

• Record Type: Journal Article
• Authors: Yang, Nuan; Liu, Hong; Zhan, Guo-qiang; Li, Da-ping
• Is Part Of: Journal of cleaner production. Volume 245(2020)
• Publication Date: 2020-02-01
• Subjects: Microbial fuel cell (MFC) -- Air-exposed biocathode -- Heterotrophic nitrifying/denitrifying (HND) -- Ammonia-contaminated wastewater -- Sustainable treatment; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2019.118923
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Air-cathode microbial fuel cells (ACMFCs) have a remarkable potential in wastewater treatment for scalable-scale and sustainable operation. In this study, a heterotrophic nitrifying/denitrifying air-cathode microbial fuel cell (HND-ACMFC) was investigated with ammonia-contaminated wastewater in long-term operation. Over an operational period of 197 d, high removal efficiencies of chemical oxygen demand (COD, 91%), ammonia (99%), and total nitrogen (TN, 95%) were achieved stably and repeatedly, with continuous bioelectricity production of 0.72 A/m 3 and maximum power density of 100 mW/m 3 . Microbial community structure analysis showed that majority of the dominated bacteria were affiliated with Thauera, Nitrosomonas, Arcobacter, Pseudomonas, Clostridium, and Geobacter, which are identified as nitrogen-removing bacteria (NRB) and/or electrochemically active bacteria (EAB). Scanning electron microscopic analysis demonstrated the presence of a considerable number of bacteria attached to the two electrodes, even in the air-exposed part of the biocathode. Moreover, energy input/output evaluation showed that the maximum normalized energy recovery still reached 0.12–0.21 kWh/kg COD when ammonia nitrogen was depleted efficiently. These results demonstrate that HND-ACMFC is a possible approach to accomplish simultaneous wastewater treatment and energy recovery, and also enhances the activity of functional microorganisms. Hence, HND-ACMFC may benefit the sustainable treatment of ammonia-contaminated wastewater by using MFC technology in view of economical configuration/operation and high performance. Graphical abstract: Image 1 Highlights: A novel HND-SCMFC was run successfully to treat ammonia-contaminated wastewater. Stable nutrients removal and energy recovery obtained while treating wastewater non-aeratedly. High removal efficiencies of nitrogen and COD achieved to 99% and 92%, respectively. Air-exposed biocathode was beneficial for the enrichment of functional microorganism. With efficient microorganism, biocathode could sustain MFCs in long-term operation.