Possible Exhaust Gas Aftertreatment Concepts for Passenger Car Diesel Engines with Sulphur-free Fuel

Kramer, Michael J.; Abthoff, Jörg; Duvinage, F.; Ruzicka, Norbert; Krutzsch, B.; Liebscher, T.

doi:10.4271/1999-01-1328

Cited by 13 publications

(2 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The most popular is SCR technology on the basis of AdBlue as a reducing agent for NO x ; this has been introduced by some truck manufacturers in Europe for EURO IV and EURO V emission legislation. The second technology, based on the NSC (BlueTEC 1), is beside SCR (BlueTEC 2) an attractive solution mainly for passenger car application [1].…”

Section: Introductionmentioning

confidence: 99%

A Novel Approach to Catalysis for NO x Reduction in Diesel Exhaust Gas

et al. 2009

Self Cite

View full text Add to dashboard Cite

With the introduction of stringent emission standards in the US in 2007 (Tier II Bin8, 5) an exhaust aftertreatment for NO x reduction is required for compliance with the emission regulations. A new approach consists in the synergetic combination of existing technologies NSC (NO x Storage Catalyst) and SCR (Selective Catalytic Reduction) with onboard generation of ammonia as the reducing agent for the SCR. It is shown in this work that the performance of the combined system exceeds those of each one considered separately, especially after ageing. The generation of ammonia is correlated to the ammonia selectivity during the regeneration of the NSC. The selectivity is primarily dependent on the temperature, A/F ratio (Air/Fuel) and the rich time. It is shown that the development of a suitable control strategy leads to a high level of NO x reduction under transient conditions in an FTP driving cycle. Due to the complexity and high development costs of current exhaust aftertreatment systems, modelling and simulation were identified as an important aspect in the development process. A system simulation tool named ExACT (Exhaust Gas Aftertreatment Components Toolbox) developed at Daimler is presented. By using the simulation already at an early stage, specific development work can be carried out prior to the experimental work on an engine test bench.

show abstract

Section: Introductionmentioning

confidence: 99%

A Novel Approach to Catalysis for NO x Reduction in Diesel Exhaust Gas

et al. 2009

Self Cite

View full text Add to dashboard Cite

show abstract

“…A second computer controlled the dynamometer system and logged data from sensors and emissions analyzers. Emissions analyzers allowed measurement of wet CH 4 or total hydrocarbons (California Analytical Instruments), wet NOx as NO or NOx (California Analytical Instruments), dry O 2 (Horiba), dry CO 2 (Horiba), and dry CO (Horiba). Here "wet" refers to straight exhaust samples, and "dry" refers to exhaust sampled through a chiller to remove H 2 O from the sample stream.…”

Section: Engine Testing: Lean Nox Trap System and Test Platformmentioning

confidence: 99%

NOx Reduction with Natural Gas for Lean Large-Bore Engine Applications Using Lean NOx Trap Aftertreatment

Parks¹

2005

View full text Add to dashboard Cite

Large-bore natural gas engines are used for distributed energy and gas compression since natural gas fuel offers a convenient and reliable fuel source via the natural gas pipeline and distribution infrastructure. Lean engines enable better fuel efficiency and lower operating costs; however, NOx emissions from lean engines are difficult to control. Technologies that reduce NOx in lean exhaust are desired to enable broader use of efficient lean engines. Lean NOx trap catalysts have demonstrated greater than 90% NOx reduction in lean exhaust from engines operating with gasoline, diesel, and natural gas fuels. In addition to the clean nature of the technology, lean NOx traps reduce NOx with the fuel source of the engine thereby eliminating the requirement for storage and handling of secondary fuels or reducing agents. A study of lean NOx trap catalysts for lean natural gas engines is presented here. Testing was performed on a Cummins C8.3G (CG-280) engine on a motor dynamometer. Lean NOx trap catalysts were tested for NOx reduction performance under various engine operating conditions, and the utilization of natural gas as the reductant fuel source was characterized. Engine test results show that temperature greatly affects the catalytic processes involved, specifically methane oxidation and NOx storage on the lean NOx trap. Additional studies on a bench flow reactor demonstrate the effect of precious metal loading (a primary cost factor) on lean NOx trap performance at different temperatures. Results and issues related to the potential of the lean NOx trap technology for large-bore engine applications will be discussed.

show abstract