Reducing Diesel Emissions

AAPEX - Automotive Aftermarket Products Expo

Nov 4-6, 2014

AAPEX - Automotive Aftermarket Products Expo
Las Vegas, Nevada, U.S.A.
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Reducing Diesel Emissions

Delphi's innovative Selective Catalytic Reduction (SCR) Dosing System reduces CO2 and NOx emissions and improves performance, packaging, and long-term reliability of diesel engines.

In many parts of the world, diesel engines have grown from being the commercial transport powertrain of choice to also becoming the passenger car powertrain of choice. Delphi's innovative Selective Catalytic Reduction (SCR) Dosing System will help diesel engines integrate well into a more environmentally responsible future.

"The Delphi SCR Dosing System offers a breakthrough technology that can help our customers significantly maximize their CO2 and NOx emission reductions," said Larry Selby, marketing manager, Delphi diesel systems, Delphi Powertrain Systems. "Additionally, customers can reach their stringent emission goals and obtain high system value across a wide range of applications."

Currently applicable to passenger cars and light commercial vehicles, Delphi's SCR Dosing System injects aqueous urea solution at up to four times the pressure of any other comparable system. This allows the NOx reduction device to be placed close coupled to the engine, making use of the hotter environment to improve both NOx reduction and CO2 reduction potential.

"The close coupled path being pursued by Delphi allows our customers to achieve up to a 95 percent NOx reduction while saving up to 5 percent in CO2," explained Peter Spadafora, Delphi product team leader, SCR systems, Delphi Powertrain Systems. "As an experienced diesel fuel injection supplier, Delphi had an excellent combination of design and high-volume precision manufacturing expertise necessary to develop our new system."

Delphi's Selective Catalytic Reduction (SCR) Dosing System includes: (clockwise from lower left) a Dosing Injector, Heater Control Module, Engine Control Module, SCR Tank Module, Ammonia Sensor, and Ammonia Sensor Controller.

Putting on the Pressure with Compelling Value

Enabling diesel engines to further reduce vehicle emissions requires a lot of pressure … in the SCR Dosing System, that is. The SCR doser (an injector with integrated high pressure pump) is mounted in the exhaust line just ahead of the SCR catalyst, where it injects the urea solution at 20 bar directly into the exhaust system.

This Delphi improvement creates many system advantages, including:

  • Minimized mixing length (between doser and catalyst) — enables placement of the NOx reduction device closer to the engine for better thermally aided NOx conversion and reduced CO2 emissions
  • Highly diffused spray — provides homogeneous distribution of the urea solution ahead of the catalyst
  • Thermally robust product — permits nozzle to be placed directly into the exhaust stream
  • Deposit free tip — for consistent spray performance over product lifetime
  • Integrated positive displacement solenoid pump — delivers accurate, metered quantity of urea regardless of supply pressure

"These advantages provide compelling value for manufacturers who want advanced, cost-competitive, and easy-to-install technology that will help reduce CO2 and NOx emissions," said Martin Hopmann, global medium duty sales manager, Delphi diesel fuel injection equipment and SCR, Delphi Powertrain Systems.

Delphi's Selective Catalytic Reduction Dosing System features a simplified architecture to facilitate integration into a vehicle program.

Making it Modular

In addition to the SCR doser, Delphi's SCR Dosing System includes two other integral modules. The urea delivery module (UDM) supplies urea solution to the doser. The UDM can be customized to integrate specific requirements for:

  • Urea level sensing
  • Lifetime filtration
  • Heating for defrosting

The final elements of the system are the electronics and software used to control the dosing subsystem. Delphi also provides complete system services to specify and calibrate the dosing system components when customers need expert support.

Simplified and Flexible

The compact, modular design of Delphi's SCR Dosing System features simplified architecture with the integrated dosing pump injector. This helps customers easily incorporate the components into their designs and platforms, providing streamlined installation and increased packaging flexibility for individual vehicle manufacturers.

In addition, the dosing pump injector allows a wide range of mounting angles on the exhaust system (axially and radially), further increasing packaging options.

Delphi, Diesel, and Our Global Customers

Delphi is actively involved in the development of advanced diesel technology. This commitment is underscored by Delphi's 15 diesel design and engineering centers located in Europe, Asia, North America and South America, and 21 diesel manufacturing facilities in 13 countries. Delphi's investment in people and equipment provides global customers timely access to innovative, reliable, environmentally focused, and cost-effective diesel solutions.

"Diesel engines provide an outstanding solution to the issue of CO2 reduction. But, until now, the requirement to reduce NOx and CO2 simultaneously has been a challenge," concluded Spadafora. "Our SCR Dosing System will help vehicle manufacturers meet stricter NOx requirements such as EU6, Tier 2 bin 5, Tier 4, and corresponding Japanese regulations, while improving CO2 emissions."

The first production application of the Delphi SCR Dosing System is scheduled for introduction in 2013. With the innovative high-pressure SCR Dosing System, Delphi customers will realize improved emissions, increased reliability, and lower overall system cost in their diesel engine systems. To find out more, visit the Delphi SCR Dosing System information found on