Reutilize tire in microbial fuel cell for enhancing the nitrogen removal of the anammox process coupled with iron-carbon micro-electrolysis

In this study, microbial fuel cells (MFCs) were explored to promote the nitrogen removal performance of combined anaerobic ammonium oxidation (anammox) and Fe-C micro-electrolysis (CAE) systems. The average total nitrogen (TN) removal efficiency of the modified MFC system was 85.00%, while that of the anammox system was 62.16%. Additionally, the effective operation time of this system increased from six (CAE system alone) to over 50 days, significantly promoting TN removal. The enhanced performance could be attributed to the electron transferred from the anode to the cathode, which aided in reducing nitrate/nitrite in denitrification. The H+ released through the proton exchange membrane caused a decrease in the pH, facilitating Fe corrosion. The pyrolyzed waste tire used as the cathode could immobilize microorganisms, enhance electron transport, and produce a natural Fe-C micro-electrolysis system. According to the microbial community analysis, Candidatus kuenenia was the major genus involved in the anammox process. Furthermore, the SM1A02 genus exhibited the highest abundance and was enriched the fastest, and could be a novel potential strain that aids the anammox process. (c) Higher Education Press 2021

Automated summary

Microbial fuel cells were used to enhance the nitrogen removal performance of combined anaerobic ammonium oxidation and Fe-C micro-electrolysis systems. The system's effective operation time increased to over 50 days, significantly improving total nitrogen removal efficiency. Enhanced performance was attributed to electron transfer and proton exchange membrane-induced pH decrease, promoting denitrification and aiding in reducing nitrate/nitrite.