Hartl M.,TU Munich |
Seidenspinner P.,TU Munich |
Jacob E.,Emissionskonzepte Motoren UG haftungsbeschrankt |
Jacob E.,EMITEC GmbH |
Wachtmeister G.,TU Munich
Abstract Oxygenated fuel components are known to reduce soot emissions in diesel engines significantly while having little effect on NOx emissions. Several compounds were mixed with diesel fuel and tested for their emission characteristics on a 1.8 l heavy duty diesel engine. The C1-oxygenate dimethoxy methane (OME1) which contains no C-C bonds in its molecular structure was found to have the best effect on the reduction of soot and particle number emissions. OME1 belongs to the group of oxymethylene ethers (OMEn) and has the molecular structure CH3-O-(CH2-O)n-CH3 while n=1. For further investigations, a pure OME1-fuel with cetane number 48 was used which contained OME1 and additives to enhance viscosity, lubricity and cetane number. Engine testing including aftertreatment with a Pt coated oxidation catalyst (DOC) proved the soot-NOx trade-off to vanish completely even at stoichiometric operation. CO and most unburned fuel emissions were efficiently reduced by the DOC. The emission of formaldehyde and methane was measured using FTIR spectrometry. No CH2O emissions could be detected. Near stoichiometric conditions, a growing output of methane was observed, which was not converted in the DOC. This can be explained with the high share of methyl groups, which react to methane with other radicals. As OME1 shows low cetane number (CN), high volatility and weak viscosity and lubricity, the characterization of the less volatile OMEn with n=3...5 and CN > 90 is recommended. These are expected to show similar emission characteristics and might have a smaller potential of methane formation. © 2015 Elsevier Ltd. All rights reserved. Source
EMITEC GmbH | Date: 2009-01-06
Internal combustion engines, namely, engines not for land vehicles; Catalytic converters and catalyst substrates for internal-combustion engines. Electrical and electronic monitoring apparatus and closed and open-loop control apparatus to be used to monitor and control catalytic converters, and parts specifically used for the apparatus. Internal combustion engines for land vehicles.
EMITEC GmbH | Date: 2008-09-16
CATALYTIC CONVERTERS FOR INTERNAL COMBUSTION ENGINES; CATALYTIC CONVERTERS CONTAINING CATALYST SUBSTRATES FOR CLEANING EXHAUST GASES FOR USE IN INTERNAL COMBUSTION ENGINES; CATALYTIC CONVERTERS FOR THE TRACTION OR PROPULSION SYSTEMS OF LAND, AIR AND WATER VEHICLES; CATALYTIC CONVERTERS CONTAINING CATALYST SUBSTRATES FOR USE IN CLEANING EXHAUST GASES FOR USE IN TRACTION OR PROPULSION SYSTEMS OF LAND, AIR AND WATER VEHICLES.
EMITEC GmbH | Date: 2009-05-26
[ Internal combustion engines for machine operation, except for land vehicles; ] components of internal combustion engines, namely, catalytic converters and catalyst substrates. Electrical and electronic monitoring and closed and open-loop control apparatus to be used to monitor and control catalytic converters. [ Internal combustion engines for land vehicles included in this class ].
Jayat F.,EMITEC GmbH |
Seifert S.,EMITEC GmbH |
Fathepurkar M.,Emitec Emission Control Technologies India Pvt. Ltd.
SAE Technical Papers
The Selective Catalytic Reduction (SCR) is the main after-treatment solution for high efficient diesel engines under development to cope with future lower fuel consumption and NOx emissions requirements (EU6+ legislation). Exhaust gas temperatures are decreasing too, leading to new after-treatment system developments in a close coupled position. Nevertheless before all vehicle architectures allow it, SCR systems are and will still be installed in underbody position. The current paper deals with an underbody metal SCR after-treatment systems, which is capable of active thermal management, and an ultra-compact SCR dosing system. These technologies are described and emission results obtained on several application examples (from passenger cars to light duty commercial vehicles) are presented and discussed in conjunction with an effective active thermal management of the SCR function. It is shown that the NO2/ NOx ratio as well as the temperature level at SCR system inlet, among all the parameters governing the SCR efficiency play an important role for the feasibility and the acceptance of an underbody SCR solution. Copyright © 2013 SAE International and Copyright © 2013 SIAT, India. Source