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Deposit Reduction in SCR Aftertreatment Systems by Addition of Ti-Based Coordination Complex to UWS
Technical Paper
2019-01-0313
ISSN: 0148-7191, e-ISSN: 2688-3627
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Abstract
Formation of urea-derived deposits in selective catalytic reduction (SCR) aftertreatment systems continues to be problematic at temperatures at and below 215 °C. Several consequences of deposit formation include: NOx and NH3 slip, exhaust flow maldistribution, increased engine backpressure, and corrosion of aftertreatment components. Numerous methods have been developed to reduce deposit formation, but to date, there has been no solution for continuous low-temperature dosing of Urea-Water Solution (UWS). This manuscript presents a novel methodology for reducing low-temperature deposit formation in SCR aftertreatment systems. The methodology described herein involves incorporation and dissolution of an HNCO hydrolysis catalyst directly into the UWS. HNCO is a transient species formed by the thermolysis of urea upon injection of UWS into the aftertreatment system. Ideally HNCO undergoes hydrolysis to form NH3 and CO2, but under certain conditions HNCO may polymerize or react with other constituents in the exhaust. Reaction of HNCO with species other than water generally results in the formation of deposits in the aftertreatment system. Addition of an HNCO hydrolysis catalyst directly into the UWS provides maximum contact between catalyst and substrate, thereby improving deposit reduction efficacy. This method of reducing deposits has been shown to reduce deposits by 89% at a 215 °C operating condition.
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Hartley, R., Henry, C., Eakle, S., and Tonzetich, Z., "Deposit Reduction in SCR Aftertreatment Systems by Addition of Ti-Based Coordination Complex to UWS," SAE Technical Paper 2019-01-0313, 2019, https://doi.org/10.4271/2019-01-0313.Data Sets - Support Documents
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References
- Schaber , P.M. , Colson , J. , Higgins , S. , Thielen , D. et al. Thermal Decomposition (Pyrolysis) of Urea in an Open Reaction Vessel Thermochimica Acta 424 1 131 142 2004 10.1016/j.tca.2004.05.018
- Strots , V.O. , Santhanam , S. , Adelman , B.J. , Griffin , G.A. et al. Deposit Formation in Urea-SCR Systems SAE International Journal of Fuels and Lubricants 2 2 283 289 2009 10.4271/2009-01-2780
- Eakle , S. , Kroll , S. , Yau , A. , Gomez , J. et al. Investigation of Urea Derived Deposits Composition in SCR Systems and their Potential Effect on Overall PM Emissions SAE Technical Paper 2016-01-0989 2016 10.4271/2016-01-0989
- Floyd , R. , Kotrba , A. , Martin , S. , and Prodin , K. Material Corrosion Investigations for Urea SCR Diesel Exhaust Systems SAE Technical Paper 2009-01-2883 2009 10.4271/2009-01-2883
- Betageri , V. , Rajagopalan , M. , Murthy , S.D. , and Thondavadi , A. Effects of Diesel Exhaust Fluid (DEF) Injection Configurations on Deposit Formation in the SCR System of a Diesel Engine SAE Technical Paper 2016-28-0109 2016 2016 10.4271/2016-28-0109
- Bernhard , A.M. , Peitz , D. , Elsener , M. , Schildhauer , T. et al. Catalytic Urea Hydrolysis in the Selective Catalytic Reduction of NOx: Catalyst Screening and Kinetics on Anatase TiO2 and ZrO2 Catalysis Science & Technology 3 4 942 951 2013 10.1039/C2CY20668D
- Lundström , A. , Snelling , T. , Morsing , P. Pär Gabrielsson et al. 2011 Urea Decomposition and HNCO Hydrolysis Studied over Titanium Dioxide, Fe-Beta and γ-Alumina Applied Catalysis B, Environmental 106 3 4 10.1016/j.apcatb.2011.05.010
- Barreau , M. , Courtois , X. , and Can , F. FT-IR Spectroscopy Study of HNCO Adsorption and Hydrolysis over Oxide-Based Samples Dedicated to deNOx Processes Applied Catalysis a: General 552 147 153 2018 10.1016/j.apcata.2017.12.019
- Van De Velde , G.M.H. , Harkema , S. , and Gellings , P.J. The Crystal and Molecular Structure of Ammonium Titanyl Oxalate Inorganica Chimica Acta 11 243 252 1974 10.1016/S0020-1693(00)93716-2
- Wang , D. , Hui , S. , and Liu , C. Mass Loss and Evolved Gas Analysis in Thermal Decomposition of Solid Urea Fuel 207 268 273 2017 10.1016/j.fuel.2017.06.117