tailieunhanh - Voltage reversal during the operation of a sediment bioelectrochemical system integrated in a brackish aquaculture model - Causes and solutions

In this study, we studied the effects of different environmental factors such as light, temperature and air humidity and of internal SBES factors such as sulfate concentration, dissolved oxygen concentration and biocathode on voltage reversal in the SBES. | VNU Journal of Science Natural Sciences and Technology Vol. 37 No. 3 2021 57-65 Original Article Voltage Reversal During the Operation of a Sediment Bioelectrochemical System Integrated in a Brackish Aquaculture Model Causes and Solutions Tran Hong Nhung Vu Ha Phuong Pham The Hai VNU University of Science 334 Nguyen Trai Thanh Xuan Hanoi Vietnam Received 15 August 2021 Revised 30 August 2021 Accepted 31 August 2021 Abstract The sediment bioelectrochemical system SBES is expected to become a novel biotechnology with numerous outstanding application potentials such as in-situ bioremediation and pathogen control. Nevertheless one of the prevalent problems when applying the SBES in practice is the voltage drop or reverse voltage of the system. In this study we studied the effects of different environmental factors such as light temperature and air humidity and of internal SBES factors such as sulfate concentration dissolved oxygen concentration and biocathode on voltage reversal in the SBES. Light temperature and air humidity did not appear to be associated with voltage reversal. Sulfate concentration in the SBES tank water did not either significantly change during voltage reversals indicating that sulfate did not compete with the anode for electrons. On the other hand the change in dissolved oxygen DO concentration and biofilm formation on the cathode appeared to be the major factors causing such phenomenon. Therefore aeration and frequent replacements of the cathode are suggested to overcome the problem which will help to enhance the practical applicability of the SBES. Keywords Power decrease power density SMFC electricity generation voltage drop voltage reversal. 1. Introduction MFCs SBESs convert chemical energy to electrical energy with the aid of A sediment bioelectrochemical system microorganisms as biocatalysts 3 . sediment BES or SBES is a BES with an Electrochemical organisms residing on the anode embedded in the anaerobic sediment and anode such as those