Single microbial fuel cell reactor for coking wastewater treatment: Simultaneous carbon and nitrogen removal with zero alkaline consumption

Di Wu; Xiaoyun Yi; Rong Tang; Chunhua Feng; Chaohai Wei

doi:10.1016/j.scitotenv.2017.11.262

Single microbial fuel cell reactor for coking wastewater treatment: Simultaneous carbon and nitrogen removal with zero alkaline consumption

Sci Total Environ. 2018 Apr 15:621:497-506. doi: 10.1016/j.scitotenv.2017.11.262. Epub 2017 Nov 28.

Authors

Di Wu¹, Xiaoyun Yi¹, Rong Tang¹, Chunhua Feng², Chaohai Wei¹

Affiliations

¹ The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China.
² The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; Guangdong Provincial Engineering and Technology Research Center for Environmental Risk Prevention and Emergency Disposal, South China University of Technology, Guangzhou 510006, PR China. Electronic address: chfeng@scut.edu.cn.

PMID: 29195198
DOI: 10.1016/j.scitotenv.2017.11.262

Abstract

The use of several individual reactors for sequential removal of organic compounds and nitrogen, in addition to the required alkaline addition in aerobic reactors, remain outstanding technical challenges to the traditional biological treatment of coking wastewater. Here, we report the utilization of a single microbial fuel cell (MFC) reactor that performs simultaneous carbon and nitrogen removal with zero alkaline consumption, as evidenced by the results of the batch-fed and continuous-flow experiments. The MFC exhibited faster reaction kinetics for COD and total nitrogen (TN) removal than the same configured reactor analogous to the traditional aerobic biological reactor (ABR). At a hydraulic retention time (HRT) of 125 h, the efficiencies of COD and TN removal in the MFC reached 83.8±3.6% and 97.9±2.1%, respectively, much higher than the values of 73.8±2.9% and 50.2±5.0% obtained in the ABR. Furthermore, the degradation in the MFC of the main organic components, including phenolic compounds (such as phenol, 2-methylphenol, 3-methylphenol, 4-methylphenol, and 2,4-dimethlyphenol) and nitrogenous heterocyclic compounds (such as quinolone, pyridine, indole, and isoquinolone) was greater than that in the ABR. The enhancing effect was attributed to the ability of the MFC to self-adjust the pH. It was also manifested by the increased abundances of heterotrophs, nitrifiers, and denitrifiers in the MFC. The correlations between the current density and the rates of COD and TN removal suggest that the extent of the current from the anode to the cathode is a critical parameter for the overall performance of MFCs in the treatment of coking wastewater.

Keywords: Bacterial composition; Bioelectrochemical technology; Electrical stimulation; Industrial wastewater treatment; Simultaneous nitrification and denitrification.