The Removal of Toluene by a Granular Activated Carbon Bioreactor using Yeast

Yeast와 입상활성탄을 이용한 미생물반응기의 휘발성유기화합물 분해 특성

  • NamGung, Hyeong-Kyu (Department of Civil and Environmental Engineering, Sejong University) ;
  • Shin, Seung-Kyu (Department of Civil and Environmental Engineering, Sejong University) ;
  • Ahmed, Zubair (Department of Environmental and Biotechnology Engineering, Hallym University) ;
  • Song, Ji-Hyeon (Department of Civil and Environmental Engineering, Sejong University)
  • 남궁형규 (세종대학교 토목환경공학과) ;
  • 신승규 (세종대학교 토목환경공학과) ;
  • ;
  • 송지현 (세종대학교 토목환경공학과)
  • Published : 2008.12.31

Abstract

A liquid culture of yeast "Candida tropicalis" was used in a fluidized bioreactor to achieve high removal efficiencies of volatile organic compounds (VOCs). In this study, granular activated carbon (GAC) was used as a fluidized material to improve adsorptive capacity as well as mass transfer of gaseous toluene, the model VOC. The GAC fluidized bioreactor demonstrated toluene removal efficiencies ranging from 50 to 80%, when inlet toluene loading varied in a range between 13.1 and 37.4 g/m$^3$-hr. The maximum elimination capacity determined in the GAC fluidized bioreactor was 172 g/m$^3$-hr at a toluene loading of 291 g/m$^3$-hr. Transient loading experiments revealed that the removal efficiency was remained unchanged during an increased loading period, and toluene introduced to the bioreactor was first absorbed to GAC and then slowly desorbed and became available to the yeast culture. Hence the fluidized GAC helped to achieve an improved mass transfer between the gas and liquid phases, resulting in high toluene removal capacity. Consequently, the GAC fluidized bioreactor using C. tropicalis can be successfully applied for the removal of VOCs, and is a feasible alternative over conventional processes such as packed-bed biofilters.

본 연구는 yeast의 한 종류인 Candida tropicalis 배양액을 유동상 반응기 형태로 운전하여 대표적인 휘발성유기화합물인 톨루엔의 제거효율을 향상시키기 위해 수행되었으며, 톨루엔 흡착과 물질전달 능력을 동시에 향상시키기 위해서 생물반응기의 유동상 물질로는 입상활성탄(GAC)을 사용하였다. 효모를 적용한 GAC 유동상반응기는 유입 톨루엔 부하 13.1$\sim$37.4 g/m$^3$-hr 범위에서 50$\sim$80%의 처리효율을 나타내었다. 또한 톨루엔 유입부하 291 g/m$^3$-hr 조건에서 최대분해능 172 g/m$^3$-hr을 얻어, 본 연구의 GAC 유동상반응기가 안정적이면서도 높은 처리효율을 나타낼 수 있음을 확인하였다. 충격부하 실험에서는 유입농도의 갑작스런 변화에도 일정하게 처리효율을 유지함으로써, 유입농도의 변화에도 안정적인 반응기 운전이 가능하다는 것을 알 수 있다. 최대분해능실험 결과 유입농도가 2배 이상 증가하였으나 처리효율은 일정하게 유지되었으며, 유입된 톨루엔이 GAC에 먼저 흡착된 후 천천히 탈착되어 효모에 의해 분해됨을 확인하였다. 따라서 유동상으로 투입된 GAC가 톨루엔의 물질전달을 향상시켜 미생물반응기의 전체 처리효율을 증가시켰다.

Keywords

References

  1. Devinny, J. S., Deshusses, M. A., and Webster T. S., "Biofiltration for air pollution control," CRC Lewis Publishers(1999)
  2. Kennes, C. and Veiga, M. C., "Bioreactors for waste gas treatment," Kluwer Academic Publishers(2001)
  3. Shareefdeen, Z. and Singh, A., "Biotechnology for odor and air pollution control," Springer(2005)
  4. Kinney, K. A., Loehr, R. C., and Corsi R. L., "Vaporphase bioreactors: avoiding problems through better design and operation," Environ. Prog., 18, 222-230(1999) https://doi.org/10.1002/ep.670180319
  5. Xi, J., Hu, H.-Y., and Qian, Y., "Effect of operating conditions on long-term performance of a biofilter treating gaseous toluene: Biomass accumulation and stablerun time estimation," Biochem. J., 31(2), 165-172(2006)
  6. Song, J. and Kinney, K. A., "Effect of Vapor-Phase Bioreactor Operation on Biomass Accumulation, Distribution, and Activity," Biotechnol. Bioeng., 68, 508-516(2000) https://doi.org/10.1002/(SICI)1097-0290(20000605)68:5<508::AID-BIT4>3.0.CO;2-P
  7. Ensley, B. D. and Kurisko, P. R., "A gas lift bioreactor for removal of contaminants from the vapor phase," Appl. Environ. Microbiol., 60(1), 285-290(1994)
  8. Lee, S. B., Strand, S. E., and Stensel, H. D., "Sustained Degradation of Trichloroethylene in a Suspended Growth Gas Treatment Reactor by an Actinomycetes Enrichment," Environ. Sci. Technol., 34(15), 3261-3268(2000) https://doi.org/10.1021/es9907515
  9. Neal, A. B. and Loehr, R. C. "Use of biofilters and suspended-growth reactors to treat VOCs," Waste Manage., 20(1), 59-68(2000) https://doi.org/10.1016/S0956-053X(99)00297-4
  10. Shim, H. and Yang, S.-T., "Biodegradation of benzene, toluene, ethylbenzene, and o-xylene by a coculture of Pseudomonas putida and Pseudomonas fluorescens immobilized in a fibrous-bed bioreactor," J. Biotechnol., 67(2-3), 99-112(1999) https://doi.org/10.1016/S0168-1656(98)00166-7
  11. Jung, I.-G. and Park, C.-H., "Characteristics of Rhodococcus pyridinovorans PYJ-1 for the biodegradation of benzene, toluene, m-xylene (BTX), and their mixtures," J. Biosci. Bioeng., 97(6), 429-431(2004) https://doi.org/10.1016/S1389-1723(04)70232-7
  12. van Groenestijn, J. W., van Heiningen, W. N. M., and Kraakman, N. J. R., "Biofilters based on the action of fungi," Water Sci. Technol., 44(9), 227-232(2001)
  13. van Groenestijn, J. W. and Liu, J. X., "Removal of alpha-pinene from gases using biofilters containing fungi," Atmos. Environ., 36(35), 5501-5508(2002) https://doi.org/10.1016/S1352-2310(02)00665-9
  14. Woertz J. R., Kinney K. A., and McIntosh N. D. P. "Removal of toluene in a vapor-phase bioreactor containing a strain of the dimorphic black yeast Exophiala lecanii-corni," Biotechnol. Bioeng., 75(5), 550-558(2001) https://doi.org/10.1002/bit.10066
  15. Yan, J., Jianping, W., Hongmei, L., Suliang, Y., and Zongding, H., "The biodegradation of phenol at high initial concentration by the yeast Candida tropicalis," Biochem. Eng. J., 24(3), 243-247(2005) https://doi.org/10.1016/j.bej.2005.02.016
  16. Yan, J., Jianping, W., Jing, B., Daoquan, W., and Zongding, H., "Phenol biodegradation by the yeast Candida tropicalis in the presence of m-cresol," Biochem. Eng. J., 29(3), 227-234(2006) https://doi.org/10.1016/j.bej.2005.12.002
  17. Abumaizar, R. J., Kocher, W., and Smith, E. H., "Biofiltration of BTEX contaminated air streams using compostactivated carbon filter media," J. Hazard. Mat., 60(2), 111-126(1998) https://doi.org/10.1016/S0304-3894(97)00046-0
  18. Bordel, S., Munoz, R., and Diaz, L. F., "Mechanistic model for evaluating the performance of suspended growth bioreactors for the off-gas treatment of VOCs," Biochem. Eng. J., 38(3), 395-405(2008) https://doi.org/10.1016/j.bej.2007.08.004
  19. 류희옥, 장용근, 김상돈, "Airlift 생물반응기," 한국생물공학회지, 9(4), 347-364(1994)
  20. 홍성호, 이충식, 이제근, "제올라이트/폴리에틸렌 복합 담체를 이용한 biotrickling filter에서 톨루엔 제거 특성," 대한환경공학회지, 27(6), 573-580(2005)