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An Urea Lean NOx Catalyst System for Light Duty Diesel Vehicles
ISSN: 0148-7191, e-ISSN: 2688-3627
Published October 01, 1995 by SAE International in United States
Annotation ability available
Future European air quality standards for light duty diesel vehicles will include stringent NOx emission regulations. In order to meet these regulations, a lean NOx catalyst system may be necessary. Since the catalytic removal of NOx is very difficult with the large concentration of oxygen present in diesel exhaust, a reductant is usually added to the exhaust to increase the NOx conversion. This paper describes a lean NOx catalyst system for a Transit light-duty truck which uses a reductant solution of urea in water.
In this work, a microprocessor was used to vary the amount of the reductant injected depending on the operating conditions of a 2,5 L naturally aspirated HSDI engine. The NOx conversions were 60% and 80% on the current European driving cycle and the U.S. FTP cycles, respectively. Data on the emissions of HC, CO, NOx, particulate mass and composition, individual HC species, aldehydes, PAH and most HC species were evaluated. No detectable levels of ammonia were emitted when the catalyst volume was optimized. The average consumption of the urea-water solution was 2,5 cc/km. Problems associated with supplying sufficient urea-water solution over the life of the vehicle are discussed.
|Technical Paper||Catalytic Reduction of Nox with Hydrocarbons Under Lean Diesel Exhaust Gas Conditions|
|Technical Paper||NOx Reduction Strategies for DI Diesel Engines|
|Technical Paper||Catalytic Reduction of NOx and Diesel Exhaust|
CitationLüders, H., Backes, R., Hüthwohl, G., Ketcher, D. et al., "An Urea Lean NOx Catalyst System for Light Duty Diesel Vehicles," SAE Technical Paper 952493, 1995, https://doi.org/10.4271/952493.
- Schöppe, D. 1991
- Dürnholz, M. Eifler, G. Endres, H. 1991
- Hüthwohl, G. Li, Q. Lepperhoff, G. x 1993
- Hüthwohl, G. Lepperhoff, G. Pischinger, F. “Catalytic Reduction of NO x in Diesel Exhaust” Paper C389/325 IMechE 1992
- Hug, H.T. Mayer, A. Hartenstein, A. “Off-Highway Exhaust Gas After-Treatment: Combining Urea-SCR, Oxidation Catalysis and Traps” SAE-Paper No. 930363 1993
- Takiguchi, M. et al. “Catalytic Engine NO x Reduction of Diesel Engines with New Concept On-board Ammonia Synthesis System” SAE-Paper No. 920469 1992
- Köbel, M.
- Lepperhoff, G. Hüthwohl G. Pischinger, F. “Catalytic Reduction of NO x in Diesel Exhaust” Fisita Congress 1992 London Paper No. 925022
- Weaver, C.S. McGregor, D.B. “Emissions Control Technology for Locomotive Engines” SAE-Paper No. 940453 1994
- Held, W. et al. “Catalytic NO x Reduction in Net Oxidizing Exhaust Gas” SAE-Paper No. 900496 1990
- Brandstetter, W. Bostock, P Hansen, J. 1992
- Lepperhoff, G. Hüthwohl, G. Lüers-Jongen, B. Hammerle, R.H. “Methods to Analyze Non-Regulated Emissions from Diesel Engines” SAE Paper No. 941952 1994
- Hammerle, R.H. Ketcher, D.A. Horrocks, R.W. Lepperhoff, G. Hüthwohl, G. Lüers-Jongen, B. “Emissions from Current Diesel Vehicles” SAE Paper No. 942043
- German VDI Guideline No. 2461, Paper 2
- Sax, N.I. Lewis, R.J. “Dangerous Properties of Industrial Materials” Van Nostrand Reinhold Company New York 8