Investigation on the Simulation of SCR Chemical Reaction

Abstract:

Abstract. With the global environment worsening and the consciousness of protecting environment strengthening, the limitation of noxious gas from diesel engines is becoming more and more strictly. Selective catalytic reduction (SCR) aftertreatment system has been applied to reduce Nitrogen Oxides (NOx) as a key technology. The urea solution injected into the tailpipe decomposes to ammonia, which will react with NOx on the surface of SCR catalyst. The main purpose of this paper is to study the effect of different concentrations of NO, NO2 and NH3 on the reactions taking place with SCR catalyst by simulation. Based on mass transfer equations and chemical kinetics the simulation results predict the concentrations of NO, NO2 and NH3 accurately. The mass conservation equations of species are solved by the software MATLAB. Some regulations can be revealed to improve the NOx conversion efficiency and reduced the NH3 slip.

• Periodical: Advanced Materials Research (Volume 569)
• Pages: 193-197
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.569.193
• Online since: September 2012
• Authors: Wei Wang, You Hong Xiao, Xin Na Tian
• Keywords: MATLAB, NO_x Reduction, SCR, Simulation

References

[1] Thomas L. McKinley. , Model Predictive Control: A Unified Approach for Urea-Based SCR Systems, SAE Int. J. Fuels Lubr. 3(5): 2010-01-1184, (2010).

DOI: 10.4271/2010-01-1184

[2] Ming-Feng Hsieh, Control of Diesel Engine Urea Selective Catalyst Reduction Systems,. PhD Dissertation, Ohio State University, (2010).

[3] T. V. Johnson, Review of Diesel emissions and control, SAE 2010 World Congress, SAE paper 2010-01-0301, (2010).

[4] M. Hsieh, M. Canova, and J. Wang, Model Predictive Control Approach for AFR Control during Lean NOx Trap Regenerations, SAE 2009 World Congress, SAE Paper 2009-01-0586, (2009).

DOI: 10.4271/2009-01-0586

[5] M. Hsieh, J. Wang, and M. Canova, Two-level nonlinear model predictive control for lean NOx trap regenerations, ASME Journal of Dynamic Systems, Measurement and Control, Vol. 132, 041001 (13 pages), (2010).

DOI: 10.1115/1.4001710

[6] M. Hsieh, M. Canova, and J. Wang, Model predictive control approach for AFR control during lean NOx trap regenerations, SAE International Journal of Fuels and Lubricants, Vol. 2, No. 1, p.149 – 157, (2009).

DOI: 10.4271/2009-01-0586

[7] Tinghong Tao, Yuming Xie, Steven Dawes and Isabelle Melscoet-Cgauvel. Diesel SCR NOx Reduction and Performance on Washcoated SCR Catalysts [C]. SAE, 2004-01-1293.

DOI: 10.4271/2004-01-1293

[8] Shinichi Saito, Ritsuko Shinozaki, Akira Suzuki, Hiroshi Jyoutaki and Yoshinaka Takeda. Development of Urea-SCR System for Commercial Vehicle-Basic Characteristics and Improvement of NOx Conversion at Low Load Operation [C]. SAE, 2003-01-3248.

DOI: 10.4271/2003-01-3248

[9] C. Scott Sluder, John M.E. Storey, Samuel A. Lewis and Linda A. Lewis. Low Temperature Urea Decomposition and SCR Performance [C]. SAE, 2005-01-1858.

DOI: 10.4271/2005-01-1858

[10] R.J. Ong, J.T. Dawley and P.G. Clem: submitted to Journal of Materials Research (2003).

[10] Maruthi N. Devarakonda, Dynamic Modeling, Simulation and Development of Model-Based Control Strategies in a Urea-SCR Aftertreatment System in Heavy Duty Diesel Engines, PhD Dissertation, Michigan Technological University, (2008).

[11] E. Tronconi, L. Lietti, P. Forzatti, and S. Malloggi. Experimental and Theo-retical Investigation of the Dynamics of the SCR-DeNOx Reaction, Chemical Engineering Science, 51(11): 2965–2970, (1996).

DOI: 10.1016/0009-2509(96)00182-0