Initial results of Peugeot 208 and 508 model testing by the French Ministry of Ecology, Sustainable Development and Energy comply with new regulations thanks to a change in the technology. The results, says Peugeot Citroen, confirm the effectiveness of the BlueHDi after-treatment system for diesel exhaust.
In the BlueHDi system, selective catalytic reduction (SCR) technology is positioned upstream of the particulate filter to eliminate up to 90 percent of the nitrogen (NOx) released by the diesel engine. This drops NOx emissions down to levels similar to gasoline engines, while maintaining the diesel engine advantage of lower CO2 emissions and greater fuel efficiency.
The Peugeot Citroen BlueHDi system has been implemented on select diesel-powered vehicles from the company since 2013. It has been gradually added as standard equipment on diesel models sold as Euro 6 compliant.
The SCR technology represents an investment of several hundred million euros and some 100 technology patents. This new testing confirms that the system conforms to 2017 Euro 6.2 standards (which begin in September 2017). There are three primary elements to the BlueHDi system includng an oxidation catalyst, SCR technology, and a diesel particulate filter.
The oxidation catalyst is mounted against the engine, converting unburned hydrocarbons (HC) and CO into water and CO2. The SCR converts NOx into water and nitrogen using AdBlue (a common urea treatment). Its change is its optimization of the tuning of the engine to favor consumption and specific performance. The diesel particulate filter then reduces 99.9 percent of the particulate number.
More test results are expected as the testing continues. The system is illustrated in the video below.Source: