Selective catalytic reduction converter design: The effect of ammonia nonuniformity at inlet

Thiyagarajan Paramadayalan; Atul Pant

Korean Journal of Chemical Engineering, Vol.30, No.12, 2170-2177, December, 2013

DOI10.1007/s11814-013-0155-z Export Citation

Selective catalytic reduction converter design: The effect of ammonia nonuniformity at inlet

Thiyagarajan Paramadayalan^†, and Atul Pant¹

GM Powertrain-India, Engine CAE, GM Tech Center, Bangalore 560066, India
¹Global General Motors R&D, India Science Lab, GM Tech Center, Bangalore 560066, India

E-mail:

A three-dimensional CFD model of SCR converter with detailed chemistry is developed. The model is used to study the effects of radial variation in inlet ammonia profile on SCR emission performance at different temperatures. The model shows that radial variation in inlet ammonia concentration affects the SCR performance in the operating range of 200-400 ℃. In automotive SCR systems, ammonia is non-uniformly distributed due to evaporation/reaction of injected urea, and using a 1D model or a 3D model with flat ammonia profile at inlet for these conditions can result in erroneous emission prediction. The 3D SCR model is also used to study the effect of converter design parameters like inlet cone angle and monolith cell density on the SCR performance for a non-uniform ammonia concentration profile at the inlet. The performance of SCR is evaluated using DeNOx efficiency and ammonia slip.

Keywords:Catalytic Converter;SCR Converter;CFD;Numerical Modeling;Monolith Reactor;Chemical Kinetics

[References]

Lambert C, Hammerle R, McGill R, Khair M, Sharp C, Technical advantages of urea SCR for light-duty and heavy-duty diesel vehicle applications, SAE 2004-01-1292 (2004)
Olsson L, Sjovall H, Blint RJ, Appl. Catal. B: Environ., 81(3-4), 203 (2008)
Wurzenberger JC, Wanker R, Multi-scale SCR modeling, 1D kinetic analysis and 3D system simulation, SAE 2005-01-0948 (2005)
Zhang X, Romzek M, Computational fluid dynamics (CFD) applications in vehicle exhaust system, SAE 2008-01-0612 (2008)
Jeong SJ, Lee SJ, Kim WS, Lee CB, Simulation on the optimum shape and location of urea injector for urea-SCR system of heavy-duty diesel engine to prevent NH3 slip, SAE 2005-01-3886.
Koebel M, Elsener M, Kleemann M, Catal. Today, 59(3-4), 335 (2000)
Yim SD, Kim SJ, Baik JH, Nam IS, Mok YS, Lee JH, Cho BK, Oh SH, American Chemical Society., 43, 4856 (2004)
McKinley TL, Alleyne AG, Lee CF, Mixture non-uniformity in SCR systems: Modeling and uniformity index requirements for steady-state and transient operation, SAE 2010-01-0883 (2010)
Johansson A, Wallin U, Karlsson M, Isaksson A, Bush P, Investigation on uniformity indices used for diesel exhaust aftertreatment systems, SAE 2008-01-0613 (2008)
Zheng G, Palmer G, Salanta G, Kotrba A, Mixer development for urea SCR applications, SAE 2009-01-2879 (2009)
Zhang X, Romzek M, 3-D numerical study of flow mixing in front of SCR for different injection systems, SAE 2007-01-1578 (2007)
Cho I, Lee S, Kang H, Baik DS, A study on the NOx reduction of urea-selective catalytic reduction (SCR) system in a heavyduty diesel engine, SAE 2007-01-3447 (2007)
Jeong SJ, Lee SJ, Kim WS, Lee CB, Simulation on the optimum shape and location of urea injector for urea-SCR system of heavy-duty diesel engine to prevent NH3 slip, SAE 2005-01-3886 (2005)
Helden VR, Verbeek R, Willems F, vander Welle R, Optimization of urea SCR deNOx systems for HD diesel engines, SAE 2004-01-0154 (2004)
Way P, Viswanathan K, Preethi P, Gilb A, Zambon N, Blaisdell J, SCR performance optimization through advancements in aftertreatment packaging, SAE 2009-01-0633 (2009)
Yi Y, Development of a 3D numerical model for predicting spray, urea decomposition and mixing in SCR systems, SAE 2007-01-3985 (2007)
Chen M, Williams S, Modelling and optimization of SCRexhaust aftertreatment systems, SAE 2005-01-0969 (2005)
Zhang X, Gomulka T, Romzek M
Karlsson M, Wallin U, Fredholm S, Jansson J, Wahlstrom GO, Schar CM, Onder CH, Guzzella L, A Combined 3D/lumped modeling approach to ammonia SCR after-treatment systems: Application to mixer designs, SAE 2006-01-0469 (2006)
Benjamin SF, Roberts CA, The porous medium approach applied to CFD modelling of SCR in an automotive exhaust with injection of urea droplets, in IMechE Conference Internal Combustion Engines: Performance, Fuel Economy and Emissions, London (2007)
Tamaldin N, Roberts CA, Benjamin SF, Experimental study of SCR in a light-duty diesel exhaust to provide data for validation of a CFD model using the porous medium approach, SAE 2010-01-1177 (2010)
Chae HJ, Choo ST, Choi H, Nam IS, Yang HS, Song SL, Ind. Eng. Chem. Res., 39(5), 1159 (2000)
Frobert A, Creff Y, Raux S, Charial C, Audouin A, Gagnepain L, SCR for passenger car: Ammonia-storage issue on a Fe-ZSM5 catalyst, SAE 2009-01-1929 (2009)
STAR-CD, STAR-CD Users Guide and Methodology, version 4.12, Computational Dynamics Ltd. (2010)
Yakhot V, Orszag SA, Thangam S, Gatski TB, Speziale CG, Phys. Fluids A: Fluid Dynamics., 4, 1510 (1992)
Kays WM, Morrow W, Compact heat exchangers, McGraw-Hill Book Company (1964)
Jeong SJ, Kim WS, Chem. Eng. Process., 42(11), 879 (2003)
Breuer J, Bruck R, Diewald R, Hirth P, Breuer, R. Bruck, R. Diewald and P. Hirth on a metal catalyst system, SAE 971028 (1997)
Narayanaswamy K, He Y, Modeling of copper-zeolite and ironzeolite selective catalytic reduction (SCR) catalysts at steady state and transient conditions, SAE 2008-01-0615 (2008)
Hughes KW, Gian D, Calleja J, Relative benefits of various cell density ceramic substrates in different regions of the FTP cycle, SAE 2006-01-1065 (2006)
Lauderdale SC, Nickerson ST, Pesansky JD, Sorensen CM, Impact of ceramic substrate web thickness on emission light-off, pressure drop, and strength, SAE 2008-01-0808 (2008)

[Referenced By]

[1] Lambert C, Hammerle R, McGill R, Khair M, Sharp C, Technical advantages of urea SCR for light-duty and heavy-duty diesel vehicle applications, SAE 2004-01-1292 (2004)

[2] Olsson L, Sjovall H, Blint RJ, Appl. Catal. B: Environ., 81(3-4), 203 (2008)

[3] Wurzenberger JC, Wanker R, Multi-scale SCR modeling, 1D kinetic analysis and 3D system simulation, SAE 2005-01-0948 (2005)

[4] Zhang X, Romzek M, Computational fluid dynamics (CFD) applications in vehicle exhaust system, SAE 2008-01-0612 (2008)

[5] Jeong SJ, Lee SJ, Kim WS, Lee CB, Simulation on the optimum shape and location of urea injector for urea-SCR system of heavy-duty diesel engine to prevent NH3 slip, SAE 2005-01-3886.

[6] Koebel M, Elsener M, Kleemann M, Catal. Today, 59(3-4), 335 (2000)

[7] Yim SD, Kim SJ, Baik JH, Nam IS, Mok YS, Lee JH, Cho BK, Oh SH, American Chemical Society., 43, 4856 (2004)

[8] McKinley TL, Alleyne AG, Lee CF, Mixture non-uniformity in SCR systems: Modeling and uniformity index requirements for steady-state and transient operation, SAE 2010-01-0883 (2010)

[9] Johansson A, Wallin U, Karlsson M, Isaksson A, Bush P, Investigation on uniformity indices used for diesel exhaust aftertreatment systems, SAE 2008-01-0613 (2008)

[10] Zheng G, Palmer G, Salanta G, Kotrba A, Mixer development for urea SCR applications, SAE 2009-01-2879 (2009)

[11] Zhang X, Romzek M, 3-D numerical study of flow mixing in front of SCR for different injection systems, SAE 2007-01-1578 (2007)

[12] Cho I, Lee S, Kang H, Baik DS, A study on the NOx reduction of urea-selective catalytic reduction (SCR) system in a heavyduty diesel engine, SAE 2007-01-3447 (2007)

[13] Jeong SJ, Lee SJ, Kim WS, Lee CB, Simulation on the optimum shape and location of urea injector for urea-SCR system of heavy-duty diesel engine to prevent NH3 slip, SAE 2005-01-3886 (2005)

[14] Helden VR, Verbeek R, Willems F, vander Welle R, Optimization of urea SCR deNOx systems for HD diesel engines, SAE 2004-01-0154 (2004)

[15] Way P, Viswanathan K, Preethi P, Gilb A, Zambon N, Blaisdell J, SCR performance optimization through advancements in aftertreatment packaging, SAE 2009-01-0633 (2009)

[16] Yi Y, Development of a 3D numerical model for predicting spray, urea decomposition and mixing in SCR systems, SAE 2007-01-3985 (2007)

[17] Chen M, Williams S, Modelling and optimization of SCRexhaust aftertreatment systems, SAE 2005-01-0969 (2005)

[18] Zhang X, Gomulka T, Romzek M

[19] Karlsson M, Wallin U, Fredholm S, Jansson J, Wahlstrom GO, Schar CM, Onder CH, Guzzella L, A Combined 3D/lumped modeling approach to ammonia SCR after-treatment systems: Application to mixer designs, SAE 2006-01-0469 (2006)

[20] Benjamin SF, Roberts CA, The porous medium approach applied to CFD modelling of SCR in an automotive exhaust with injection of urea droplets, in IMechE Conference Internal Combustion Engines: Performance, Fuel Economy and Emissions, London (2007)

[21] Tamaldin N, Roberts CA, Benjamin SF, Experimental study of SCR in a light-duty diesel exhaust to provide data for validation of a CFD model using the porous medium approach, SAE 2010-01-1177 (2010)

[22] Chae HJ, Choo ST, Choi H, Nam IS, Yang HS, Song SL, Ind. Eng. Chem. Res., 39(5), 1159 (2000)

[23] Frobert A, Creff Y, Raux S, Charial C, Audouin A, Gagnepain L, SCR for passenger car: Ammonia-storage issue on a Fe-ZSM5 catalyst, SAE 2009-01-1929 (2009)

[24] STAR-CD, STAR-CD Users Guide and Methodology, version 4.12, Computational Dynamics Ltd. (2010)

[25] Yakhot V, Orszag SA, Thangam S, Gatski TB, Speziale CG, Phys. Fluids A: Fluid Dynamics., 4, 1510 (1992)

[26] Kays WM, Morrow W, Compact heat exchangers, McGraw-Hill Book Company (1964)

[27] Jeong SJ, Kim WS, Chem. Eng. Process., 42(11), 879 (2003)

[28] Breuer J, Bruck R, Diewald R, Hirth P, Breuer, R. Bruck, R. Diewald and P. Hirth on a metal catalyst system, SAE 971028 (1997)

[29] Narayanaswamy K, He Y, Modeling of copper-zeolite and ironzeolite selective catalytic reduction (SCR) catalysts at steady state and transient conditions, SAE 2008-01-0615 (2008)

[30] Hughes KW, Gian D, Calleja J, Relative benefits of various cell density ceramic substrates in different regions of the FTP cycle, SAE 2006-01-1065 (2006)

[31] Lauderdale SC, Nickerson ST, Pesansky JD, Sorensen CM, Impact of ceramic substrate web thickness on emission light-off, pressure drop, and strength, SAE 2008-01-0808 (2008)