The Euro VI legislation due to take effect in 2014 requires an 80% reduction in NOX emissions compared with the Euro V standard. It is also expected that there will be a limit set for ammonia slip to control the amount of ammonia released from an SCR system. Read also more about SCR systems here: http://bit.ly/scr-systems

1. SCR System and Performance Innovation (Part 1)
The Euro 6/VI regulations concerning greenhouse gas emissions from vehicles present manufacturers
with the challenge of reducing several different gases using several different technologies
incorporated into the same exhaust system. The reduction of NOX emissions alongside the reduction
of CO2 has been a particular challenge for diesel engine manufacturers, and this has accelerated the
advances in selective catalytic reduction (SCR) technology to meet NOX emission standards.
The Euro VI legislation due to take effect in 2014 requires an 80% reduction in NOX emissions
compared with the Euro V standard. It is also expected that there will be a limit set for ammonia slip
to control the amount of ammonia released from an SCR system. Several manufacturers are
developing systems and components that aim to achieve such high levels of efficiency.
Delphi SCR dosing system
Delphi Automotive has developed an SCR system that improves performance and reliability of the
system, as well as reducing NOX and CO2 emissions. The new system, due to be introduced in 2012,
injects aqueous urea solution into the SCR system at up to four times the pressure of previous
systems, and reduces CO2 by up to 1g/km when compared with similar systems.
Source: Delphi
The system is made up of three components. The SCR doser, which is an injector with high pressure
pump, injects the urea solution directly into the exhaust at a pressure of 20 bar. The urea solution is
fed to the doser by a low pressure pump situated in the Urea Delivery module (UDM). The whole
process is controlled by the electronics and software used to manage the system.
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2. Rather than use a timed injector opening, the Delphi system uses a positive displacement solenoid
pump, which delivers accurate measured quantities of urea solution regardless of the supply
pressure.
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IQPC GmbH | Friedrichstr. 94 | D-10117 Berlin, Germany
t: +49 (0) 30 2091 3330 | f: +49 (0) 30 2091 3263 | e: eq@iqpc.de | w: www.iqpc.de
Visit IQPC for a portfolio of topic-related events, congresses, seminars and conferences: www.iqpc.de