This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Improvement in Selective Catalytic Reduction Model Accuracy for Predicting NO x Conversion at High Temperature
Technical Paper
2018-01-0346
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
As a result of WNTE regulations and the introduction of close-coupled aftertreatment systems, exhaust purification at high temperatures in commercial vehicles has become increasingly important in recent years. In this report, we improve the prediction accuracy for NOx conversion at high temperatures in the kinetic model of conventional Cu-selective catalytic reduction (Cu-SCR). Reaction rate analysis indicated that the rate of NH3 oxidation was extremely low compared to the rate of standard SCR. We found that NOx concentration-dependent NH3 oxidations (termed NOx-assisted NH3 oxidations) were key to the rate of NH3 oxidation. The output of the improved Cu-SCR kinetic model was in agreed with experimental results obtained from the synthetic gas bench and engine dynamometer bench. We analyzed the contribution of each reaction to NH3 consumption during Cu-SCR. Under NH3 + NO + O2, standard SCR was dominant at low temperature. At high temperatures, the rate of NO-assisted NH3 oxidation increased, and this reaction competed with standard SCR. Under NH3 + NO + NO2 + O2, fast SCR, NH4NO3 formation, and standard SCR were the dominant reactions at low temperature. With increasing temperature, NO2-assisted NH3 oxidation competed with the other reactions, resulting in a decreased NOx conversion.
Recommended Content
Authors
- Kohei Oka - Isuzu Advanced Engineering Center Ltd.
- Teppei Ohori - Isuzu Advanced Engineering Center Ltd.
- Yutaka Itagaki - Isuzu Advanced Engineering Center Ltd.
- Kazuo Osumi - Isuzu Advanced Engineering Center Ltd.
- Naoya Ishikawa - Isuzu Advanced Engineering Center Ltd.
- Yuuki Dobashi - Isuzu Motors, Ltd.
- Eiji Wako - Isuzu Motors, Ltd.
Citation
Oka, K., Ohori, T., Itagaki, Y., Osumi, K. et al., "Improvement in Selective Catalytic Reduction Model Accuracy for Predicting NOx Conversion at High Temperature," SAE Technical Paper 2018-01-0346, 2018, https://doi.org/10.4271/2018-01-0346.Also In
References
- Beale , A. , Gao , F. , Lezcano-Gonzalez , I. , Peden , C.H.F. , and Szanyi , J. Recent Advances in Automotive Catalysis for NOx Emission Control by Small-Pore Microporous Materials Chemical Society Reviews 44 7371 7405 2015
- Olsson , L. , Sjövall , H. , and Blint , R.J. A Kinetic Model for Ammonia Selective Catalytic Reduction over Cu-ZSM-5 Applied Catalysis B: Environmental 81 203 217 2008
- Chatterjee , D. , Kočí , P. , Schmeißer , V. , Marek , M. et al. Modelling of a combined NOx Storage and NH3-SCR catalytic system for Diesel exhaust gas aftertreatment Catalysis Today 151 395 409 2010
- Colombo , M. , et al. 3 2 197 243 255 2012
- Chatterjee , D. et al. Numerical Simulation of Ammonia SCR-Catalytic Converters: Model Development and Application SAE Technical Paper, 2005-01-0965 2005 10.4271/2005-01-0965
- Chatterjee , D. et al. Numerical Simulation of Zeolite- and V-Based SCR Catalytic Converters SAE Technical Paper, 2007-01-1136 2007 10.4271/2007-01-1136
- He , Yongsheng
- He , Yongsheng Development of an Integrated One-Dimensional Model of Advanced Diesel Aftertreatment System Thermo- and Fluid Dynamic Processes in Diesel Engines 2006
- Sampara , C. , et al. 2007
- Hepburn , J.S. et al. Experimental and Modeling Investigation of NOx Trap Performance SAE Paper 962051 1996
- Hepburn , J.S. et al. Engine and Aftertreatment Modeling for Gasoline Direct Injection SAE Paper 982596 1998
- Kamasamudram , K. , Currier , N.W. , Chen , X. , and Yezerets , A. Overview of the Practically Important Behaviors of Zeolite-Based Urea-SCR Catalysts, Using Compact Experimental Protocol Catalysis Today 151 212 222 2010
- Markatou , P. et al. Fe-Zeolite SCR Model Development, Validation and Application SAE Technical Paper, 2011-01-1304 2011 10.4271/2011-01-1304
- Song , X. et al. A Modeling Study of SCR Reaction Kinetics from Reactor Experiments SAE Technical Paper, 2013-01-1576 2013 10.4271/2013-01-1576
- Nedyalkova , R. , Kamasamudram , K. , Currier , N.W. , Li , J. et al. Experimental Evidence of the Mechanism behind NH 3 Overconsumption during SCR over Fe-Zeolites Journal of Catalysis 299 101 108 2013
- Joshi , S.Y. , Kumar , A. , Luo , J. , Kamasamudram , K. et al. Combined Experimental and Kinetic Modeling Study of the Bi-Modal NOx Conversion Profile on Commercial Cu-SAPO-34 Catalyst under Standard SCR Conditions Applied Catalysis B: Environmental 165 27 35 2015
- Bacher , V. , Perbandt , C. , Schwefer , M. , Siefert , R. et al. Kinetics of Ammonia Consumption during the Selective Catalytic Reduction of NO x over an Iron Zeolite Catalyst Applied Catalysis B: Environmental 162 158 166 2015