Application of low-density electric current to performance improvement of membrane bioreactor treating raw municipal wastewater
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The main objective of this study was to investigate the effect of low-density electrical current application on the performance of a laboratory-scale membrane bioreactor (MBR) treating municipal wastewater. The MBR operation was divided in two experimental runs: without (run I) and with electrocoagulation process (run II). The results demonstrated that the use of electrocoagulation process was beneficial for organic matter and nutrient removal, enabling the average removal efficiencies for COD, NH4+–N and PO43−–P of 98.5, 99.8 and 99.2%, respectively. Despite the decreasing of MLVSS/MLSS ratio during the period with electrocoagulation, both autotrophic and heterotrophic biomass activities have increased. Data from the 16S RNA genetic sequencing showed that the electric current application affected the nitrifying bacteria population, specially the genre Nitrospira, which exhibited a significant increase in its relative abundance. Such behavior probably occurred due to electrostimulation phenomenon that can improve microbial metabolism and increase cell growth. These results demonstrate that the electric currents application can improve the MBRs performance on wastewater treatment.
KeywordsElectrocoagulation Electrostimulation Microbial community composition Biomass activity Phosphorus removal
The authors would like to acknowledge the Brazilian National Council for Scientific and Technological Development (CNPq) and Coordination of Superior Level Staff Improvement (CAPES) for their financial support.
- Alimohammadi M, Askari M, Dehghani MH, Dalvand A, Saeedi R, Yetilmezsoy K, Heibati B, McKay G (2017) Elimination of natural organic matter by electrocoagulation using bipolar and monopolar arrangements of iron and aluminum electrodes. Int J Environ Sci Technol 4(10):2125–2134. https://doi.org/10.1007/s13762-017-1402-3 CrossRefGoogle Scholar
- Caporaso JG, Lauber CL, Walters WA, Berg-Lyons D, Huntley J, Fierer N, Owens SM, Betley J, Fraser L, Bauer M, Gormley N, Gilbert JA, Smith G, Knight R (2012) Ultra-high-throughput microbial community analysis on the Illumina HiSeq and MiSeq platforms. The ISME J 6:1621–1624. https://doi.org/10.1038/ismej.2012.8 CrossRefGoogle Scholar
- Gonzalez-Martinez A, Leyva-Diaz JC, Rodriguez-Sanchez A, Munoz-Palazon B, Rivadeneyra A, Poyatos JM et al (2015) Isolation and metagenomic characterization of bacteria associated with calcium carbonate and struvite precipitation in a pure moving bed biofilm reactor-membrane bioreactor. Biofouling 31(4):333–348. https://doi.org/10.1080/08927014.2015.1040006 CrossRefGoogle Scholar
- Goud RK, Mohan SV (2013) Prolonged applied potential to anode facilitate selective enrichment of bio-electrochemically active Proteobacteria for mediating electron transfer: microbial dynamics and bio-catalytic analysis. Biores Technol 137:160–170. https://doi.org/10.1016/j.biortech.2013.03.059 CrossRefGoogle Scholar
- Huang W, Wang W, Shi W, Lei Z, Zhang Z, Chen R, Zhou B (2014) Use low direct current electric field to augment nitrification and structural stability of aerobic granular sludge when treating low COD/NH4-N wastewater. Biores Technol 171:139–144. https://doi.org/10.1016/j.biortech.2014.08.043 CrossRefGoogle Scholar
- Judd S, Judd C (2011) The MBR book: principles and applications of membrane bioreactors in water and wastewater treatment, 2nd edn. Oxford, Elsevier LtdGoogle Scholar
- Li L, Dong Y, Qian G, Hu X, Ye L (2018) Performance and microbial community analysis of bio-electrocoagulation on simultaneous nitrification and denitrification in submerged membrane bioreactor at limited dissolved oxygen. Biores Technol 258:168–176. https://doi.org/10.1016/j.biortech.2018.02.121 CrossRefGoogle Scholar
- Metcalf and Eddy (2014) Wastewater engineering—treatment and reuse, 5th edn. McGraw-Hill, BostonGoogle Scholar
- Tang B, Yu C, Bin L, Zhao Y, Feng X, Huang S, Chen Q (2016) Essential factors of an integrated moving bed biofilm reactor–membrane bioreactor: adhesion characteristics and microbial community of the biofilm. Biores Technol 211:574–583. https://doi.org/10.1016/j.biortech.2016.03.136 CrossRefGoogle Scholar
- Zeyoudi M, Altenaiji E, Ozer LY, Ahmed I, Yousef AF, Hasan SW (2015) Impact of continuous and intermittent supply of electric field on the function and microbial community of wastewater treatment electro-bioreactors. Electrochim Acta 181:271–279. https://doi.org/10.1016/j.electacta.2015.04.095 CrossRefGoogle Scholar