LUXEMBOURG — Delphi Automotive has developed a breakthrough in NOx control for diesel engines with a new selective catalytic reduction (SCR) system that improves the performance, packaging and long-term reliability of the system as well as reduces vehicle CO2 emissions by up to 1g/km over any comparable system, according to the company.

By injecting aqueous urea solution into a SCR system at up to four times the pressure of any previous system, which allows the catalyst to be close coupled to the engine, Delphi says it has solved many of the issues associated with other SCR systems.

“As the EU regulations for CO2 emissions take effect, every additional gram of CO2 could potentially cost the manufacturer up to 95 euros per vehicle in future emissions-related penalties,” said Peter Spadafora, Delphi product team leader, SCR Systems. “The Delphi SCR system reduces both NOx and CO2 emissions in order to add maximum value for our customers.”

The system consists of three basic modules. The SCR doser (an injector with integrated high-pressure pump) is mounted in the exhaust line just ahead of the SCR catalyst and injects the urea solution at 20 bar directly into the exhaust stream. The solution is supplied to the injector by a low pressure pump within the Urea Delivery Module (UDM) in the remote urea tank. The third element of the system is the electronics and software used to control the dosing subsystem.