International Journal of Naval Architecture and Ocean Engineering

The Society of Naval Architects of Korea (대한조선학회)
권호 표지
DOI QR코드

DOI QR Code

Numerical analysis of NOx reduction for compact design in marine urea-SCR system

  • Choi, Cheolyong (Graduate Program, School of Mechanical Engineering, Pusan National University) ;
  • Sung, Yonmo (Department of Mechanical Engineering, Imperial College London) ;
  • Choi, Gyung Min (School of Mechanical Engineering, Pusan National University) ;
  • Kim, Duck Jool (School of Mechanical Engineering, Pusan National University)
  • Received : 2015.06.09
  • Accepted : 2015.08.19
  • Published : 2015.11.30
Download PDF
⟨ Previous Next ⟩

Abstract

In order to design a compact urea selective catalytic reduction system, numerical simulation was conducted by computational fluid dynamics tool. A swirl type static mixer and a mixing chamber were considered as mixing units in the system. It had great influence on flow characteristics and urea decomposition into ammonia. The mixer caused flow recirculation and high level of turbulence intensity, and the chamber increased residence time of urea-water-solution injected. Because of those effects, reaction rates of urea decomposition were enhanced in the region. When those mixing units were combined, it showed the maximum because the recirculation zone was significantly developed. $NH_3$ conversion was maximized in the zone due to widely distributed turbulence intensity and high value of uniformity index. It caused improvement of $NO_x$ reduction efficiency of the system. It was possible to reduce 55% length of the chamber and connecting pipe without decrease of $NO_x$ reduction efficiency.

Keywords

References

  1. Andersson, B., Andersson, R., Hakansson, L., Mortensen, M., Sudiyo, R. and Van Wachem, B., 2011. Computational fluid dynamics for engineers. Cambridge: Cambridge University Press.
  2. Baik, J.H., Yim, S.D., Nam, I.S., Mok, Y.S., Lee, J.H., Cho, B.K. and Oh, S.H., 2006. Modeling of monolith reactor washcoated with CuZSM5 catalyst for removing NO from diesel engine by urea. Industrial & engineering chemistry research, 45(15), pp.5258-5267. https://doi.org/10.1021/ie060199+
  3. Birkhold, F., Meingast, U., Wassermann, P. and Deutschmann, O. 2006. Analysis of the injection of urea-water-solution for automotive SCR $DeNO_x$-systems: modeling of two-phase flow and spray/wall-interaction, SAE Technical Paper, 2006-01-0643. Pennsylvania: 4 SAE International.
  4. Birkhold, F., Meingast, U., Wassermann, P. and Deutschmann, O., 2007. Modeling and simulation of the injection of ureawater-solution for automotive SCR $DeNO_x$-systems. Applied Catalysis B: Environmental, 70(1), pp.119-127. https://doi.org/10.1016/j.apcatb.2005.12.035
  5. Brack, W., Heine, B., Birkhold, F., Kruse, M., Schoch, G., Tischer, S. and Deutschmann, O., 2014. Kinetic modeling of urea decomposition based on systematic thermogravimetric analyses of urea and its most important by-products. Chemical Engineering Science, 106, pp.1-8. https://doi.org/10.1016/j.ces.2013.11.013
  6. Chen, M. and Williams, S., 2005. Modelling and optimization of SCR-exhaust aftertreatment systems. SAE Technical Paper, 2005-01-0969. Pennsylvania: 4 SAE International.
  7. Choi, C., Sung, Y., Choi, G.M. and Kim, D.J., 2015. Numerical Analysis of Urea Decomposition with Static Mixers in Marine SCR System. Journal of Clean Energy Technologies, 3(1), pp. 39-42. https://doi.org/10.7763/JOCET.2015.V3.165
  8. Choi, G.M., Kim, T.K., Sung, Y.M. and Kim, D.J., 2013. Mixer for fluid mixing in the pipe. KR patent, No. 10-1340889.
  9. Ebrahimian, V., Nicolle, A. and Habchi, C., 2012. Detailed modeling of the evaporation and thermal decomposition of urea‐water solution in SCR systems. AIChE Journal, 58(7), pp.1998-2009. https://doi.org/10.1002/aic.12736
  10. FLUENT, 2011. Fluent 14.0 theory guide. Canonsburg, PA: ANSYS Inc.
  11. IMO, 2015a. Nitrogen Oxides (NOx)-regulation 13, International Maritime Organization. [online] Available at : .
  12. IMO, 2015b. Sulfur Oxides (SOx)-regulation 14, International Maritime Organization. [online] Available at : .
  13. Kim, J.Y., Ryu, S.H. and Ha, J.S., 2004. Numerical prediction on the characteristics of spray-induced mixing and thermal decomposition of urea solution in SCR system. In ASME 2004 Internal Combustion Engine Division Fall Technical Conference, Long Beach, California, USA, 24-27 October 2004, pp.165-170.
  14. Kim, T.K., 2013. Effect of using mixer on back pressure performance and mixing with urea solution in SCR system. M.S. thesis. Department of Mechanical Engineering, Pusan National University.
  15. Koebel, M. and Elsener, M., 1998. Selective catalytic reduction of NO over commercial $DeNO_x$-catalysts: experimental determination of kinetic and thermodynamic parameters. Chemical Engineering Science, 53(4), pp.657-669. https://doi.org/10.1016/S0009-2509(97)00342-4
  16. Koebel, M., Elsener, M. and Kleemann, M., 2000. Urea-SCR: a promising technique to reduce $NO_x$ emissions from automotive diesel engines. Catalysis today, 59(3), pp.335-345. https://doi.org/10.1016/S0920-5861(00)00299-6
  17. Lefebvre, A., 1988. Atomization and sprays. USA: CRC press.
  18. Olsson, L., Sjovall, H. and Blint, R.J., 2008. A kinetic model for ammonia selective catalytic reduction over Cu-ZSM-5. Applied Catalysis B: Environmental, 81(3), pp.203-217. https://doi.org/10.1016/j.apcatb.2007.12.011
  19. O'Rourke, P.J. and Amsden, A.A., 1987. The TAB method for numerical calculation of spray droplet breakup, SAE Technical Paper, 872089. Pennsylvania: 4 SAE International.
  20. Park, T., Sung, Y., Kim, T., Lee, I., Choi, G. and Kim, D., 2014. Effect of static mixer geometry on flow mixing and pressure drop in marine SCR applications. International Journal of Naval Architecture and Ocean Engineering, 6(1), pp.27-38. https://doi.org/10.2478/IJNAOE-2013-0161
  21. Regner, M., Ostergren, K. and Tragardh, C., 2006. Effect of geometry and flow rate on secondary flow and the mixing process in static mixers-A numerical study. Chemical Engineering Science, 61(18), pp.6133-6141. https://doi.org/10.1016/j.ces.2006.05.044
  22. Samuelsson, E. and Holmberg, S., 2013. A CFD study of the urea supply, droplet breakup and mixing in a pipe upstream of a SCR catalyst. M.S. thesis. Department of Chemical and Biochemical engineering, Chalmers University of Technology.
  23. Song, X., Naber, J.D. and Johnson, J.H. 2014. A study of the effects of NH3 maldistribution on a urea-selective catalytic reduction system. International Journal of Engine Research, 16(2), pp.213-222. https://doi.org/10.1177/1468087414532462
  24. Thakur, R.K., Vial, C., Nigam, K.D.P., Nauman, E.B. and Djelveh, G., 2003. Static mixers in the process industries-a review. Chemical Engineering Research and Design, 81(7), pp.787-826. https://doi.org/10.1205/026387603322302968
  25. Turns, S.R., 2000. An introduction to combustion: Concept and Applications. New York: McGraw-hill.
  26. Yim, S.D., Kim, S.J., Baik, J.H., Nam, I.S., Mok, Y.S., Lee, J.H., Mok, Y.S., Lee, J.H., Cho, B.K and Oh, S.H., 2004. Decomposition of urea into NH3 for the SCR process. Industrial & engineering chemistry research, 43(16), pp.4856-4863. https://doi.org/10.1021/ie034052j
  27. Zhang, X. and Romzek, M. 2007. 3-D numerical study of flow mixing in front of SCR for different injection systems, SAE Technical Paper, 2007-01-1578. Pennsylvania: 4 SAE International.
  28. Zheng, G., Fila, A., Kotrba A. and Floyd, R., 2010. Investigation of urea deposits in urea SCR systems for medium and heavy duty trucks, SAE Technical Paper, 2010-01-1941. Pennsylvania: 4 SAE International.
  29. Zheng, G., Palmer, G., Salanta G. and Kotrba, A., 2009. Mixer development for urea SCR application, SAE Technical Paper, 2009-01-2879. Pennsylvania: 4 SAE International.

Cited by

  1. Integrated Study of Inland-Vessel Diesel Engine Two-Cell SCR Systems With Dynamic References vol.22, pp.3, 2015, https://doi.org/10.1109/tmech.2016.2596102
  2. Installation and characteristics of urea-selective catalytic reduction systems for nitrogen oxide reduction in marine diesel engine vol.231, pp.3, 2015, https://doi.org/10.1177/1475090217699679
  3. Numerical simulation of fluid flow and mixing process in a SCR denitration system vol.397, pp.None, 2018, https://doi.org/10.1088/1757-899x/397/1/012100
  4. Numerical study on the design of urea decomposition chamber in LP SCR system vol.11, pp.1, 2015, https://doi.org/10.1016/j.ijnaoe.2018.06.005
  5. Performance Optimization of High-pressure SCR System in a Marine Diesel. Part II: Catalytic Reduction and Process vol.62, pp.1, 2015, https://doi.org/10.1007/s11244-018-1088-x
  6. Performance Optimization of High-Pressure SCR System in a Marine Diesel Engine. Part I: Flow Optimization and Analysis vol.62, pp.1, 2015, https://doi.org/10.1007/s11244-018-1124-x
  7. Application Study on a New Hybrid Canning Structure of After-Treatment System for Diesel Engine vol.13, pp.3, 2015, https://doi.org/10.3390/en13030734
  8. Numerical analysis of mixing chamber non-uniformities and feed conditions for optimal performance of urea SCR vol.5, pp.12, 2015, https://doi.org/10.1039/d0re00269k
  9. Numerical investigation of the high pressure selective catalytic reduction system impact on marine two-stroke diesel engines vol.13, pp.None, 2015, https://doi.org/10.1016/j.ijnaoe.2021.09.003
  10. SCR 믹서형상에 따른 배기가스와 환원제 혼합 효율에 관한 실험적 연구 vol.22, pp.3, 2015, https://doi.org/10.5762/kais.2021.22.3.74
  11. Spraying and Mixing Characteristics of Urea in a Static Mixer Applied Marine SCR System vol.14, pp.18, 2015, https://doi.org/10.3390/en14185788
  12. Optimisation design of short pitch spiral hybrid SCR structure for improving the exhaust performance vol.235, pp.14, 2015, https://doi.org/10.1177/09544070211011093
  13. Hybrid power and propulsion systems for ships: Current status and future challenges vol.156, pp.None, 2022, https://doi.org/10.1016/j.rser.2021.111965