DOI QR코드

DOI QR Code

The Effect of Electrode Spacing and Size on the Performance of Soil Microbial Fuel Cells (SMFC)

전극간 거리와 크기가 토양미생물연료전지의 성능에 미치는 영향

  • Im, Seong-Won (Department of Environmental Engineering, Green Technology Institute (GTI), Gyeongnam National University of Science and Technology (GNTECH)) ;
  • Lee, Hye-Jeong (Department of Environmental Engineering, Green Technology Institute (GTI), Gyeongnam National University of Science and Technology (GNTECH)) ;
  • Chung, Jae-Woo (Department of Environmental Engineering, Green Technology Institute (GTI), Gyeongnam National University of Science and Technology (GNTECH)) ;
  • Ahn, Yong-Tae (Department of Energy Engineering, GNTECH)
  • 임성원 (경남과학기술대학교 환경공학과, 녹색기술연구소) ;
  • 이혜정 (경남과학기술대학교 환경공학과, 녹색기술연구소) ;
  • 정재우 (경남과학기술대학교 환경공학과, 녹색기술연구소) ;
  • 안용태 (경남과학기술대학교 에너지공학과)
  • Received : 2014.10.31
  • Accepted : 2014.11.17
  • Published : 2014.11.30

Abstract

Soil microbial fuel cells (SMFC) have gained a great attention as an eco-friendly technology that can simultaneously generate electricity and treat organic pollutants from the contaminated soil. We evaluated the effect of electrode spacing and size on the performance of SMFC treating soil contaminated with organic pollutants. Maximum power density decreased with increase in electrode distance or decrease in electrode size, likely due to higher internal resistance. The maximum voltage and power density decreased from 326 mV and $19.5mW/m^2$ with 4 cm of electrode distance to 222 mV and $5.9mW/m^2$ with 9 cm of electrode distance. In case of electrode size test, the maximum voltage and power density generated was 291 mV, $0.34mW/m^3$ when both of anode and cathode area were $64cm^2$ with 4 cm of electrode distance. The maximum voltage decreased by 19~29% when the anode area decreased to $16cm^2$ while only 3~12% of voltage decreased with cathode area decrease. The maximum power density decreased by 49~68% with decreasing anode size, and by 29~47% with decreasing cathode size. These results showed that the anode area had more significant effects than the cathode area on the power generation of SMFC which has a high internal resistance due to a coexistence of soil and wastewater in the reactor.

토양 내에서 유기성 오염물질은 혐기성 미생물에 의해 분해되지만 전자수용체의 부족으로 상당량이 토양에 잔류하게 된다. 토양미생물연료전지(soil microbial fuel cells, SMFC)는 전극을 통해 전자 소비를 증진시켜 유기물 분해를 촉진시키고 동시에 전력도 생산하기 때문에, 다양한 유기성 오염원으로 오염된 토양을 환경 친화적으로 복원시킬 수 있는 기술로서 많은 관심을 받고 있다. 본 연구에서는 전극간 거리와 전극 크기가 SMFC의 전기적 성능에 미치는 영향을 연구하였다. 유기물이 풍부한 토양과 인공폐수 혼합물을 이용하여 SMFC를 단일반응조로 구성하였다. SMFC에서 발생된 전력량은 전극간 거리가 멀어지거나 전극 크기가 작아질수록 내부저항이 증가하여 감소하였다. 전극 크기는 $64cm^2$로 고정하고 전극간 거리는 4~9 cm로 변화를 주었을 때, 전극간 거리가 4 cm 조건에서 최대전압 326 mV, 최대전력밀도 $19.5mW/m^2$가 얻어졌고 거리가 멀어질수록 전압발생량은 19~32% 감소하고 최대전력밀도는 56~69% 감소하는 것으로 나타났다. 전극 크기 변화 실험에서는 전극간 거리를 4 cm로 고정하고 전극 크기를 $16{\sim}64cm^2$로 변화를 주었다. 두 전극 크기가 $64cm^2$ 조건에서 최대전압 291 mV, 최대전력밀도 $0.34mW/m^3$로 측정되었으며 산화전극 크기가 작아지면, 최대전압은 19~29% 감소하였고, 환원전극의 경우는 3~12% 감소하였다. 최대전력밀도는 산화전극이 작아지면, 49~68% 감소하였고, 환원전극이 작아지는 경우에는 29~47% 감소하였다. SMFC는 인공폐수와 토양 혼합물질을 반응기 내부물질로 사용하기 때문에, 전자 및 이온전달속도가 느려 환원전극 크기에 비해 산화전극 크기에 더 많은 영향을 받는 것으로 판단된다.

Keywords

References

  1. Logan, E. L., Hamelers, B., Rozendal, R., Schroder, U., Keller, J., Freguia, S., Aelterman, P., Verstraete, W. and Ravaey, K., "Microbial Fuel Cells: Methodology and Technology," Environ. Sci. Technol., 40(17), 5181-5192(2006). https://doi.org/10.1021/es0605016
  2. Han, S.-K., "Microbial fuel Cells: Principles and applications to Environmental health," J. Environ. Health Sci., 38(2), 83-94(2012). https://doi.org/10.5668/JEHS.2012.38.2.083
  3. Kazuya, W., "Recent development in microbial fuel cell technologies for sustainable bioenergy," J. Biosci. Bioeng., 106(6), 528-536(2008). https://doi.org/10.1263/jbb.106.528
  4. Deng, H., Wu, Y.-C., Zhang, F., Huang, Z.-C., Zhen, Z., Xu, H.-J. and Zhao, F., "Factors affecting the performance of single-chamber soil microbial fuel cells for power generation," Pedosphere, 24(3), 330-338(2014). https://doi.org/10.1016/S1002-0160(14)60019-9
  5. Chae, K.-J., Choi, M.-J., Kim, K.-Y., Ajayi, F. F., Chang, I.-S. and Kim, I. S., "Selective inhibition of methanogens for the improvement of biohydrogen production in microbial electrolysis cells," Int. J. Hydro. Energy, 35(24), 13379-13386(2010). https://doi.org/10.1016/j.ijhydene.2009.11.114
  6. Huang, D.-Y., Zhou, S.-G., Chen, Q., Zhao, B., Yuan, Y. and Zhuang, L., "Enhanced anaerobic degradation of organic pollutants in a soil microbial fuel cell," Chem. Eng. J., 172(2-3), 647-653(2011). https://doi.org/10.1016/j.cej.2011.06.024
  7. Venkata Mohan, S. and Chandrasekhar, K., "Solid phase microbial fuel cell (SMFC) for harnessing bioelectricity from composite food waste fermentation: influence of electrode assembly and buffering capacity," Bioresour. Technol., 102(14), 7077-7085(2011). https://doi.org/10.1016/j.biortech.2011.04.039
  8. Huan, D., Chen, Z. and Zhao, F., "Energy from plants and microorganisms: progress in plant-microbial fuel cells," Chem-SusChem, 5(6), 1006-1011(2012).
  9. Rezaei, F., Richard, T. L., Brennam, R. A. and Logan, E. L., "Substrate-Enhanced Microbial Fuel Cells for Improved Remote Power Generation from Sediment-Based Systems," Environ. Sci. Technol., 41(11), 4053-4058(2007). https://doi.org/10.1021/es070426e
  10. Wang, C.-T., Liao, F.-T. and Liu, K.-S., "Electrical analysis of compost solid phase microbial fuel cell," Int. J. Hydro. Energy, 38(25), 11124-11130(2013). https://doi.org/10.1016/j.ijhydene.2013.02.120
  11. Oliver, H., Andre, F. L. and Gerry, L., "Loss on ignition as a method for estimating organic and carbonate content in sediments: reproducibility and comparability of results," J. Paleolimnol., 25(1), 101-110(2001). https://doi.org/10.1023/A:1008119611481
  12. Song, T.-S., Wang, D.-B., Han, S., Wu, X.-Y. and Zhou, C. C., "Influence of biomass addition on electricity harvesting from solid phase microbial fuel cells," Int. J. Hydro. Energy, 39(2), 1056-1062(2014). https://doi.org/10.1016/j.ijhydene.2013.10.125
  13. Ahn, Y., Zhang, F. and Logan, E. L., "Air humidity and water pressure effects on the performance of air-cathode microbial fuel cell cathodes," J. Power Sources, 247, 655-659(2014). https://doi.org/10.1016/j.jpowsour.2013.08.084
  14. Cheng, S., Liu, H. and Logan, E. L., "Increased power generation in a continuous flow MFC with advective flow through the porous anode and reduced electrode spacing," Environ. Sci. Technol., 40(7), 2426-2432(2006). https://doi.org/10.1021/es051652w
  15. Futamata, H., Bretschger, O., Cheung, A., Kan, J., Owen, R. and Nealson, K. H., "Adaptation of soil microbes during establishment of microbial fuel cell consortium fed with lactate," J. Biosci. Bioeng., 115(1), 58-63(2013). https://doi.org/10.1016/j.jbiosc.2012.07.016
  16. An, J., Kim, B., Nam, J., Ng, H. Y. and Chang, I. S., "Comparison in performance of sediment microbial fuel cells according to depth of embedded anode," Bioresour. Technol., 127, 138-142(2013). https://doi.org/10.1016/j.biortech.2012.09.095
  17. He. Z., Huang, Y., Manohar, A. K. and Mansfeld, F., "Effect of electrolyte pH on the rate of the anodic and cathodic reactions in an air-cathode microbial fuel cell," Bioelectrochem., 74(1), 78-82(2008). https://doi.org/10.1016/j.bioelechem.2008.07.007
  18. Oh, S.-E. and Logan, E. L., "Proton exchange membrane and electrode surface areas as factors that affect power generation in microbial fuel cells," Appl. Microbiol. Biot., 70(2), 162-169(2006). https://doi.org/10.1007/s00253-005-0066-y
  19. Gangrekar, M. M. and Shinde, V. B., "Performance of membrane- less microbial fuel cell treating wastewater and effect of electrode distance and area on electricity production," Bioresour. Technol., 98(15), 2879-2885(2007). https://doi.org/10.1016/j.biortech.2006.09.050