Korean Chemical Engineering Research

The Korean Institute of Chemical Engineers (한국화학공학회)
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Effects of Organic and Inorganic Additives on Selective Non Catalytic Reduction Reaction of NOx in a Pilot Scale Flow Reactor

파일럿 규모의 흐름반응기에서 유기 및 무기 첨가제가 질소산화물의 선택적 무촉매 환원반응에 미치는 영향

  • Park, Soo Youp (Dept. of Environmental Engineering, Kwangwoon University) ;
  • Yoo, Kyung Seun (Dept. of Environmental Engineering, Kwangwoon University) ;
  • Lee, Joong Kee (Eco-Nano Research Center, Korea Institute of Science and Technology) ;
  • Park, Young Kwon (Faculty of Environmental Engineering, University of Seoul)
  • 박수엽 (광운대학교 환경공학과) ;
  • 유경선 (광운대학교 환경공학과) ;
  • 이중기 (한국과학기술연구원 나노환경연구센터) ;
  • 박영권 (서울시립대학교 환경공학부)
  • Received : 2005.10.31
  • Accepted : 2006.07.03
  • Published : 2006.10.31
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Abstract

Effects of organic and inorganic additives on the SNCR reaction of NOx were investigated in a pilot scale flow reactor with a variation of operating parameters. NOx reduction efficiency increased with the increase of a residence time and an initial NOx concentration. NOx reduction reaction by urea solution started to appear about 850 and then reached to maximum value around $970^{\circ}C$. NOx reduction efficiency also increased with the increase of NSR (Normalized Stoichiometric Ratio) up to 2.0. Addition of ethanol and phenol as an organic additives shifted the optimum temperature window to lower region with decreasing the maximum NOx reduction efficiency. This might be due to the side reaction of hydrocarbon in ethanol structure. NaOH addition widened the temperature window and enhanced the NOx reduction efficiency about 10％ due to the chain reaction of NaOH and the reduction of $N_2O$.

파일럿 크기의 흐름반응기에서 유기와 무기 첨가제가 질소산화물의 선택적 무촉매 환원반응에 미치는 영향을 공정변수 변화에 따라 고찰하였다. 질소산화물 저감효율은 반응기의 체류시간과 초기 NOx 농도 증가에 따라 증가하였다. 요소용액에 의한 NOx 환원반응은 $850^{\circ}C$에서 시작되어 $970^{\circ}C$에서는 최대값을 나타내었으며, NSR = 2.0까지 증가 하였다. 유기첨가제로서 에탄올과 페놀의 첨가는 온도창을 저온 영역으로 이동시켰으며, 에탄올 구조내의 탄화수소에 의한 부반응으로 최대의 NOx 저감효율이 감소하였다. NaOH 첨가는 NaOH의 연쇄반응과 $N_2O$ 저감으로 인하여 온도창을 확대시키고, 최대 NOx 저감효율을 10％ 정도 향상시켰다.

Keywords

Acknowledgement

Supported by : 환경부

References

  1. Lyon, R. K., 'Thermal DeNOx : How it Works,' Environmental Management, 7-12(1979)
  2. Radojevic, M., 'Reduction of Nitrogen Oxides in Flue Gases,' Environmental Pollution, 102(S1), 685-689(1998) https://doi.org/10.1016/S0269-7491(98)80099-7
  3. Cooper, C. D. and Alley, F. C., 'Air Pollution Control A Design Approach,' 2nd Ed., Waveland Press, Inc., Illinois(1994)
  4. Choi, S. W. and Choi, S. K., 'Characteristics of SNCR Process for NOx Control,' NERI, 6(1), 203-211(2001)
  5. Caton, J. A. and Siebers, D. L., 'Comparison of Nitric Oxide Removal by Cyanuric Acid and by Ammonia,' Combust. Sci. and Tech., 65, 277-293(1989) https://doi.org/10.1080/00102208908924054
  6. Jodal, M. and Nielsen, C., 'Pilot-Scale Experiments with Ammonia and Urea as Reduction in Selective Non-Catalytic Reduction of Nitric Oxide,' 23th Symposium (International) on Combustion, The Combustion Institute, 237-243(1990)
  7. Miller, J. A. and Bowman, C. T., 'Kinetic Modeling of the Reduction of Nitric Oxide in Combustion Products by Isocyanic Acid,' International Journal of Chemical Kinetics, 23, 289-313(1991) https://doi.org/10.1002/kin.550230403
  8. Sun, W. H., Stamatakis, P. and Hofmann, J. E., 'Reaction Kinetics of Selective Non-Catalytic NOx Reduction with Urea,' American Chemical Society, Division of Fuel Chemistry, 38(2), 734-747(1993)
  9. Azuhata, S., Akimoto, H. and Hishinuma, Y., 'Effect of $H_{2}O_{2}$ on Homogeneous Gas Phase NO Reduction Reaction with $NH_{3}$,' AIChE J., 28(1), 7-11(1982) https://doi.org/10.1002/aic.690280103
  10. Rota, R. and Zanoledo, E. F., 'Influence of Oxygenated Additives on the NOx OUT Process Efficiency,' FUEL, 82, 765-770 (2003) https://doi.org/10.1016/S0016-2361(02)00365-4
  11. Yoo, K. S., Lee, J. G., Park, D. K., Jeong, M. J., Lee, C. and Shin, J. W., 'The Selective Non-Catalytic Reduction of NOx Using Urea Solution in a Flow Reactor,' Korean Chem. Eng. Res., 41(2), 219-223(2003)
  12. Suhulmann, J. and Rotzoll, G., 'Experimental Characterization of the Influence of CO on the High Temperature Reduction of NO by $NH_{3}$,' FUEL, 72, 175-179(1993) https://doi.org/10.1016/0016-2361(93)90394-H
  13. Lodder, P. and Lefers, J. B., 'Effect of Natural gas, $C_{2}H_{6}$ and CO on the Homogeneous Gas Phase Reduction of NOx by $NH_{3}$,' The Chemical Engineering Journal, 30, 161-167(1985) https://doi.org/10.1016/0300-9467(85)80026-5
  14. Lee, S. M., Park, K., Kwak, T. H., Park, J. W., Makin, S. and Kim, B. H., 'The Improvement of Denitrofication by Using Sodium Salts in the SNCR Process,' Korean Chem. Eng. Res., 43(2), 324- 329(2005)
  15. Wenli, D., Dam-Johansen, K. and Ostergaard, K., 'Widening the Temperature Range of the Thermal DeNOx Process. An Experimental Investigation,' 23th Symposium (International) on Combustion, The Combustion Institute, 297-303(1990)
  16. Noda, S., Harano, A., Hashimoto, M. and Sadakata, M., 'Development Selective Noncatalytic Reduction by Ammonia in the Presence Phenol,' Combustion and Flame, 122, 439-450(2000) https://doi.org/10.1016/S0010-2180(00)00119-X
  17. Lim, Y. I., Yoo, K. S., Jeong, S. M., Kim, S. D., Lee, J. B. and Choi, B. S., 'A Study on NOx Removal form Flue Gas by Using Urea Solution,' Korean Chem. Eng. Res., 35(1), 83-89(1997)
  18. Ostberg, M. and Dam-Johansen, K., 'Empirical Modeling of The Selective Non-Catalytic Reduction of NO: Comparison With Large- Scale Experiments and Detailed Kinetic Modeling,' Chemical Engineering Science, 49(12), 1879-1904(1994) https://doi.org/10.1016/0009-2509(94)80072-3
  19. Ostberg, M. and Dam-Johansen, K., 'The Droplet Diffusion Model - An Empirical Model for Micromixing in Reacting Gas Phase Systems,' Chemical Engineering Science, 50(13), 2061- 2067(1995) https://doi.org/10.1016/0009-2509(95)00063-B
  20. Lee, J. B. and Kim, S. D., 'Kinetics of NOx Reduction by Urea Solution in a Pilot Scale Reactor,' J. Chem. Eng. Japan, 29, 620- 626(1996) https://doi.org/10.1252/jcej.29.620
  21. Ostberg, M., Dam-Johansen, K. and Johansson, J. E., 'Influence of the SNCR Process,' Chemical Engineering Science, 52(15), 2511- 2525(1997) https://doi.org/10.1016/S0009-2509(97)00069-9
  22. Zamansky, V. M., Lissianski, V. V. and Maly, P. M., 'Reactions of Sodium Species in the Promoted SNCR Process,' Combustion and Flame, 117, 821-831(1999) https://doi.org/10.1016/S0010-2180(98)00127-8
  23. Miller, J. A. and Brown, C. T., 'Mechanism and Modeling of Nitrogen Chemistry in Combustion,' Prog. Energy Combust. Sci., 15, 287-338(1989) https://doi.org/10.1016/0360-1285(89)90017-8
  24. Caton, J. A., Narney, J. K., Cariappa, C. and Laster, W. R., 'The Selective Non-Catalytic Reduction of Nitric Oxide using Ammonia at up to 15％ Oxygen,' The Canadian Journal of Chemical Engineering, 73, 345-350(1995) https://doi.org/10.1002/cjce.5450730311
  25. Jeong, S. M. and Kim, S. D., 'NOx Removal by Selective Noncatalytic Reduction with Urea Solution in a Fluidized Bed Reactor,' Korean J. Chem. Eng., 16(5), 614-617(1999) https://doi.org/10.1007/BF02708140