http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Bonyoung KOO,Sunghoon SON,Sokhee JUNG 한국생물공학회 2021 한국생물공학회 학술대회 Vol.2021 No.10
Microbial fuel cells (MFCs) are innovative bio-electrochemical systems (BES) that are being developed for an energy-positive wastewater treatment process that generates electricity from organic waste with the concurrent wastewater treatment. Activated carbon (AC) is an inexpensive catalyst for oxygen reduction in an air cathode of microbial fuel cells (MFCs). In the AC-based cathode, carbon black (CB) is used as a conductive supporting material. In this study, it was hypothesized cathodic performance would increase if reduced graphene oxide (rGO) replaces CB in an optimum ratio. Because rGO has high electrical conductivity and unique shape with flat and large areas, it can be used for improving the electrical conductivity and facilitating electron transfer in the cathodic catalyst layer by intercalation into the catalyst layer in replace of CB. rGO replaced CB in the four different weight ratios. Maximum power density was the best in rGO15 (2,642 ㎽/㎡) followed by rGO5 (2,142 ㎽/㎡). In the optimum external resistance operation, rGO5 and rGO showed similar power (~1,060 ㎽/㎡), higher than the others. Linear sweep voltammetry, cyclic voltammetry, and impedance spectroscopy also showed that the optimal rGO additions improved cathodic performance and reduced cathodic internal resistance. Due to the flatter and wider shape of rGO and 5 times higher electrical conductivity than CB, the rGO addition improved the cathodic performance, but the complete replacement of CB with rGO decreased the cathodic performance due to the increased thickness and the morphological crack. The optimum rGO addition is a simple and effective method for improving cathodic performance.
( Bonyoung Koo ),( Sokhee P. Jung ) 한국폐기물자원순환학회 2022 ISSE 초록집 Vol.2022 No.-
Although MFC has many applications, the most promising application is in wastewater treatment. MFC can be grafted into a sewage treatment plant to remove the remaining organic matter and generate energy for the operation of the sewage treatment plant. Many studies have been carried out to improve the performance of these MFCs, and they have shown the potential for commercialization of MFCs, such as showing results of grafting them with actual sewage treatment plants. The current research trend of MFC scale-up is as follows. i) development of electrodes and membranes with high economy and performance to reduce high cost, ii) development of materials resistant to contamination, corrosion and clogging for long-term operation, iii) connection of multiple modules to minimize losses Scale up in the form of a stack. However, there are still a number of obstacles that prevent scale-up. The main obstacles are high cost, low power generation due to internal losses, durability and removal of contaminants. Therefore, it is important to develop efficient electrodes and ion membranes and increase the actual wastewater treatment efficiency in order to reduce the high cost and internal losses. Looking at the results of MFC scale-up studies so far, it has been shown that stack configuration can achieve high performance by reducing internal losses, is cheaper than scaling up a single reactor, and has high pollutant handling capacity. Suggested research strategies for scale-up for future practical use are as follows. First, by using a stack type reactor, secondly by using a reactor without an ion film to reduce internal resistance and cost, thirdly by using a microbial anode as the ultimate catalyst for durability and sustainability, and finally by increasing the processing efficiency. It is to achieve high treatment efficiency through pre-treatment and post-treatment by grafting other sewage treatment processes to increase it.
Bonyoung KOO,Sunghoon SON,Sokhee JUNG 한국생물공학회 2021 한국생물공학회 학술대회 Vol.2021 No.10
Microbial fuel cell (MFC) is an innovative environmental and energy system that converts biomass energy in wastewater into electrical energy and purify wastewater by using a microbial electrochemical reaction. For the practical implementation of MFC as a next-generation wastewater treatment process, MFC performance should be enhanced far more than the current level. Characterizations of the electrochemistry of MFC is very important in developing bio-electrochemical energy producing wastewater treatment process. Compared to the development of MFC technology, however, understanding of its electrochemical characterization is still insufficient. The main reason is that its electrochemical analysis is very difficult due to the complex nature of the anode biofilm, which is a key to generating electricity. In this experiment, the influence of the measurement potential of impedance and the scanning rate for polarization curve on the MFC electrochemistry was investigated. The experiment was performed after stabilizing the system for accurate measurement. Unlike the previous batch tests showing the lowest anodic impedance at -400 ㎷ vs. Ag/AgCl, the anodic impedance decreased and the current production increased as the anode potential increased up to +5.7 mV vs. Ag/AgCl in the continuous flow MFC. The polarization curves were produced at two scanning rates (1 and 0.1 ㎷/s) in a continuous mode, and those electrochemical data were comparatively analyzed. The rapid scan rate has the advantage of being able to collect data in a short time, but the measured data differs from the performance value when operating the MFC with a constant external resistance. When it is difficult to maintain a steady state for a long time in an MFC, it will be possible to produce polarization curves in a short time with a faster scanning rate. When performance analysis is needed, the comparative analysis would be possible among the data at different conditions through extrapolation.