Journal of Korean Society of Environmental Engineers (대한환경공학회지)

Korean Society of Environmental Engineers (대한환경공학회)
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A Study on the Regeneration of SCR Catalyst Deactivated by Unburned Carbon Deposition

탄소침적으로 피독된 탈질 촉매의 재생에 관한 연구

  • Received : 2010.08.02
  • Accepted : 2010.10.22
  • Published : 2010.10.31
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Abstract

A bag filter system was partially burnt down during a trial run of waste wood incineration boiler. This brought about unburned hydrocarbon which caused a rapid deactivation of low temperature SCR catalyst set up in two stage after the bag filter. The deactivated catalyst was investigated in order to trace the origin by several characterization methods such as XRD, EDX, BET, TGA, SEM. The deactivated catalyst was regenerated by different methods such as acid washing, water washing in ultrasonication, and calcination treatment under air condition. It is found the calcination treatment under air condition at $450^{\circ}C$ for 2 hours to be the best regeneration method. The catalytic activity was measured in the form of 2 cm ${\times}$ 2 cm ${\times}$ 10 cm (catalyst weight 10 g) honeycomb type. A deNOx efficiency of the regenerated catalyst showed 100% at $180^{\circ}C$ which is the same level of fresh one.

폐 목재 소각 보일러 배가스로부터 질소산화물을 저감하기 위하여 설치된 선택적촉매환원 공정의 시운전 중에 전단에 설치된 여과포의 일부 소실이 발생되었다. 여과포 소실에 따른 불완전 연소 가스는 2단으로 설치된 저온 탈질촉매 표면을 미연탄소로 침적시켜 촉매의 탈질 효율을 급격히 저감시켰다. 활성 저하의 원인 분석을 위하여 XRD, EDX, BET, TGA, SEM 등 다양한 특성 분석을 실시하였다. 재생 방법으로 산 세척, 초음파 수 세척, 공기 중 소성의 방법을 적용한 결과, 공기분위기에서 $450^{\circ}C$로 2시간 소성하는 것이 최적조건 임을 밝혀내었다. 재생된 촉매는 2 cm ${\times}$ 2 cm ${\times}$ 10 cm(촉매 무게 10 g) Honeycomb 촉매 시료를 이용하여 활성을 측정한 결과 사용 전 촉매와 동일한 수준의 활성인 $180^{\circ}C$에서 NOx저감 효율 100%를 나타내었다.

Keywords

References

  1. Forzatti, P., "Present status and perspectives in de-NOx SCR catalysis," Appl. Catal. A, 222(1-2), 221-236(2001). https://doi.org/10.1016/S0926-860X(01)00832-8
  2. 최병선 외 21인, "화력발전소의 환경종합대책수립 연구, 최종보고서," 한국전력공사 기술연구원(1989).
  3. Hughes, R., Deactivation of Catalysts, Academic Press(1984).
  4. Forzatti, P. and Lietti, L., "Catalyst deactivation," Catal. Today, 52(2-3), 165-181(1999). https://doi.org/10.1016/S0920-5861(99)00074-7
  5. Khodayari, R. and Odenbrand, C.U.I., "Regeneration of commercial SCR catalysts by washing and sulphation: effect of sulphate groups on the activity," Appl. Catal. B, 33, 277-291(2001). https://doi.org/10.1016/S0926-3373(01)00193-X
  6. Zheng, Y., Jensen, A. D. and Johnsson, J. E., "Deactivation of $V_2O_5-WO_3-TiO_2$ SCR catalyst at a biomass-fired combined heat and power plant," Appl. Catal. B, 60, 253-264 (2005). https://doi.org/10.1016/j.apcatb.2005.03.010
  7. 문일식, 조규진, "배연 탈질용 폐촉매의 재생에 관한 연구," 공업화학, 10(2), 263-267(1999).
  8. 이상진, 홍성창, "소각로 SCR 폐탈질 촉매의 피독과 효율 재생에 관한 연구," 공업화학, 19(3), 259-263(2008).
  9. US Patent 6,387,836, 14 May 2002, SaarEnergie GmbH, Saarbruken, Germany.
  10. Nojima, S., Iida, K., Nobayashi, N. and Naito, O., "Development of NOx removal SCR catalyst for low $SO_2$ oxidation," Mitsubishi Heavy Industries, Ltd. Technical review, 38(2), 89-91(2001).
  11. 김진영, 김봉수, 가명진, 이진구, 이주헌, "폐 SCR 촉매의 재생 특성," 한국대기환경학회 2005 춘계학술대회 논문집, PD1(2005).
  12. Khodayari, R. and Odenbrand, C. U. I., "Regeneration of commercial $TiO_2-V_2O_5-WO_3$ SCR catalysts used in bio fuel plants," Appl. Catal. B, 30, 87-99(2001). https://doi.org/10.1016/S0926-3373(00)00227-7
  13. 박혜경, "질소산화물 제거용 상용 $V_2O_5-WO_3/TiO_2$ SCR 폐 촉매의 재생 효과 고찰", 대한환경공학회지, 27(8), 859-869 (2005).
  14. Kiyoura, R. and Urano, K., "Mechanism, Kinetics, and Equilibrium of Thermal Decomposition of Ammonium Sulfate," Ind. Eng. Chem. Prod. Res. Dev., 9(4), 489-494(1970). https://doi.org/10.1021/i260036a001
  15. Pasel, J., Kassner, P., Montanari, B., Gazzano, M., Vaccari, A., Makowski, W. Lojewski, T., Dziembaj, R. and Papp, H., "Transition metal oxides supported on active carbons as low temperature catalysts for the selective catalytic reduction (SCR) of NO with $NH_3$," Appl. Catal. B, 18(3-4), 199-213(1998). https://doi.org/10.1016/S0926-3373(98)00033-2
  16. Pearson, I. M., Ryu, H., Wong, W. C. and Nobe, K., "Chemical Mixed' catalysts," Ind. Eng. Chem. Prod. Res. Dev., 22(2), 381-382(1983). https://doi.org/10.1021/i300010a042
  17. Baiker, A., Dollenmeier, P. and Glinski, M., "Selective Catalytic Reduction of Nitric Oxide with Ammonia. I. Monolayer and Multilayer of Vanadia Supported on Titania," Appl. Catal., 35(2), 351-364(1987). https://doi.org/10.1016/S0166-9834(00)82872-9
  18. Bond, G. C., Zurita, J. P., Flamerz, S., Gellings, P. J., Bosch, H., van Ommen, J. G. and Kip, B. J., "Structure and Reactivity of Titania Supported Oxides; Part 1. Vanadium Oxides on Titania in the sub- and super-Monolayer Regions," Appl. Catal., 22, 361-378(1986). https://doi.org/10.1016/S0166-9834(00)82643-3