Journal of Korean Society of Environmental Engineers (대한환경공학회지)

Korean Society of Environmental Engineers (대한환경공학회)
권호 표지

Effects of MLSS Concentration and Influent C/N Ratio on the Nitrogen Removal Efficiency of Alternately Intermittently Aerated Nonwoven Fabric Filter Bioreactors

교차 간헐 포기식 부직포 여과막 생물반응조에서 MLSS 농도 및 유입수 C/N 비가 질소 제거효율에 미치는 영향

  • Jung, Kyoung-Eun (School of Environmental & Civil Engineering, Inha University) ;
  • Bae, Min-Su (School of Environmental & Civil Engineering, Inha University) ;
  • Lee, Jong-Ho (School of Environmental & Civil Engineering, Inha University) ;
  • Cho, Yun-Kyung (Department of Civil and Environmental Engineering, University of Wisconsin-Madison) ;
  • Cho, Kwang-Myeung (School of Environmental & Civil Engineering, Inha University)
  • 정경은 (인하대학교 환경토목공학부) ;
  • 배민수 (인하대학교 환경토목공학부) ;
  • 이종호 (인하대학교 환경토목공학부) ;
  • 조윤경 (위스콘신대학교 토목환경공학부) ;
  • 조광명 (인하대학교 환경토목공학부)
  • Published : 2006.05.31
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Abstract

To investigate the effects of MLSS concentration and influent C/N ratio on the nitrogen removal efficiency of alternately intermittently aerated nonwoven fabric filter bioreactors, the MLSS concentrations of the reactors were maintained at approximately 5,500 mg/L, 10,000 mg/L and 15,000 mg/L, and the influent TCOD/TKN ratio was decreased gradually from 5 to 2 by adding $NH_4Cl$. The influent was prepared by diluting a food waste leachate to a TCOD concentration of about 300 mg/L. The results of the experiment showed F/M ratios less than 0.112 g TCOD/g MLSS-day, average TCOD removal efficiencies of above 95%, and an average observed microbial yield coefficient of 0.283 g MLSS/g COD removed. The nitrification efficiencies were computed to be always better than 96% except one case where the nitrification efficiency was 90.5% when the MLSS concentration and the influent TCOD/TKN ratio was 5,500 mg/L and 2, respectively. The denitrification efficiency deteriorated as the influent TCOD/TKN ratio decreased. The average denitrification efficiency at the MLSS concentration of 10,000 mg/L was 10.7% better than that at the MLSS concentration of 5,500 mg/L, and the denitrification rate improved at a rate of 2.66 mg NL as the MLSS concentration increased by 1,000 mg/L. When the MLSS concentration was 15,000 mg/L, however, the average denitrification efficiency was merely 4.6% higher compared to when the MLSS concentration was 5,500 mg/L, and the denitrification rate increased at a rate of 0.75 mg N/L per 1,000 mg/L MLSS increase. Therefore, no strict proportional relationship was found between MLSS concentration and endogenous denitrification rate. The average alkalinity consumption rate was 3.36 mg alkalinity/mg T-N removed, which is similar to the theoretical value of 3.57 mg alkalinity/mg T-N removed, but the rate increased as the influent TCOD/TKN ratio decreased.

교대로 간헐적으로 포기되는 2개의 부직포 여과막 생물반응조로 폐수를 처리할 때 반응조의 MLSS 농도와 유입수의 C/N 비가 질소 제거효율에 미치는 영향을 파악하기 위하여 MLSS 농도를 약 5,500 mg/L, 10,000 mg/L 및 15,000 mg/L로 유지하면서 $NH_4Cl$을 첨가하여 유입수의 TCOD/TKN 비를 5, 4, 3 및 2로 감소시켰다. 유입수는 음식물 쓰레기 침출수를 COD농도가 약 300 mg/L되도록 희석시킨 것이었다. 실험 결과, 반응조의 F/M 비는 0.112 g COD/g MLSS-day 이하, COD 제거효율은 95% 이상, 그리고 미생물 성장계수($Y_{obs}$) 값은 평균 0.283 g MLSS/g COD로 나타났다. 질산화 효율은 MLSS 농도가 5,500 mg/L이고 유입수의 TCOD/TKN 비가 2인 경우의 90.5%를 제외하고 모두 96% 이상이었다. 탈질효율은 유입수의 TCOD/TKN 비가 감소할수록 악화되었다. MLSS 농도가 5,500 mg/L인 경우에 비하여 10,000 mg/L인 경우에 탈질효율이 평균 10.7% 더 높아, MLSS 농도가 1,000 mg/L 증가함에 따라 평균 2.66 mg N/L의 율로 탈질율이 증가하였다. 그러나, MLSS 농도가 15,000 mg/L로 유지된 경우에는 5,500 mg/L인 경우에 비하여 탈질효율이 평균 4.6%만 더 높아 MLSS 농도가 1,000 mg/L 증가함에 따라 평균 0.75 mg N/L의 율로 탈질율이 증가하였다. 따라서 MLSS 농도와 내생 탈질율 간에 비례관계가 성립되지 않았다. 알칼리도 소모량은 유입수의 TCOD/TKN 비가 5인 경우에 제거된 T-N 1 mg당 평균 3.36 mg으로서 이론값인 3.57 mg에 가까웠으나 유입수의 TCOD/TKN 비가 감소함에 따라 증가하는 경향을 나타내었다.

Keywords

References

  1. U. S. EPA, Manual Nitrogen Control, EPA/625/R-93/010, Washington, D. C.(1993)
  2. Timmermans, P. and van Haute, A, 'Denitrification with methanol; fundamental study of the growth and denitrification capacity of Hyphomicrobium sp.,' Water Res., 10, 1249 -1255(1983)
  3. Rittmann, B. E. and McCarty, P. L., Environmental Biotechnology: Principles and Applications, McGraw-Hill (2001)
  4. Abufayed, A. A. and Schroeder, E. D., 'Kinetics and stoichiometry of SBR/denitrification with a primary sludge carbon source,' J Water Pollut. Control. Fed., 58, 398-405(1986)
  5. Buisson, H., Cote, P., Praderie, M., and Paillard, H., 'The use of immersed membranes for upgrading wastewater treatment plants,' Water Sci. Technol., 37(9), 89-95(1988)
  6. Choi, J. H., Dockko, S., Fukushi, K., and Yamamoto, K., 'A novel application of a submerged nanofiltration membrane bioreactor(NF MBR) for wastewater treatment,' Desalination, 146, 413-420(2002) https://doi.org/10.1016/S0011-9164(02)00524-6
  7. 조광명, '여과막 활성슬러지공법에 의한 유기성 폐수의 처리,' 대한토목학회논문집, 28(6), 119-133(1980)
  8. 임상호, 배민수, 조광명, '부직포 여과막 생물반응조를 이용한 하수의 처리,' 한국물환경학회지, 19(1), 99-107 (2003)
  9. 황도연, 강복춘, 조광명, '간헐폭기식 부직포 여과막 생물반응조에서 폭기/비폭기 시간비가 하수의 유기물 및 질소 제거에 미치는 영향,' 대한환경공학회지, 25(2), 258-265(2003)
  10. 이종호, 조광명, '교차 간헐 폭기식 부직포 여과막 생물반응조를 이용한 하수의 유기물 및 질소 제거,' 대한환경공학회지, 26(2), 184-190(2004)
  11. 안윤찬, 배민수, 이종호, 조윤경, 조광명, '교대로 간헐 포기되는 부직포 여과막 생물반응조에서 C/N비가 유기물 및 질소제거 효율에 미치는 영향,' 대한환경공학회지, 27(5), 499 - 506(2005)
  12. APHA, Standard Methods for the Examination of Water and Wastewater, 20th ed., Washington D. C., USA(1988)
  13. 환경부 고시 제 96-32호, 수질환경오염공정시험법(1996)
  14. Grady, Jr., C. P. L., Daigger, G. T., and Lim, H. C., Biological Wastewater Treatment, 2nd ed., Marcel Dekker, Inc.(1999)
  15. Metcalf & Eddy, Inc., Wastewater Engineering: Treatment and Reuse, 4th ed., McGraw-Hill(2003)
  16. Batta, C. P., Matsuda, A., Kawasaki, K., and Omori, D., 'Minimization of sludge production and stable operational condition of a submerged membrane activated sludge process,' Water Sci. Technol., 50(9), 121-128 (2004)
  17. Carrera, J., Vicent, T., and Lafuente, 'Effect of influent C/N ratio on biological nitrogen removal(BNR) from high-strength ammonium industrial wastewater,' Process Biochemistry, 39, 2035-041(2004) https://doi.org/10.1016/j.procbio.2003.10.005
  18. Tseng, C. C., Potter, T. G., and Kooperrnan, B., 'Effect of influent chemical oxygen demand to nitrogen ratio on a partial nitrification/complete denitrification process,' Water Res., 32(1), 165-173(1998) https://doi.org/10.1016/S0043-1354(97)00195-4
  19. Innocenti, L., Bolzonella, D., Pavan, P., and Cecchi, F., 'Effect of sludge age on the performance of a membrane bioreactor: influence on nutrient and metals removal,' Desalination, 146, 4671-474(2002)
  20. 정경은, 배민수, 조윤경, 조광명, '부직포 여과막 생물 반응조에서의 폐활성슬러지 감량화,' 대한환경공학회지, 28(1), 88-96(2006)
  21. Burdick, C. R., Refling, D. R., and Stensel, H. D., 'Advanced biological treatment to achieve nutrient removal,' J. Water Pollut. Control Fed., 54, 1078-1086 (1982)