31 October 2001
Ford Motor Company has unveiled a diesel-powered Ford Focus research vehicle capable of meeting the ULEV standard of the very stringent California LEV II legislation, which will come to power in 2004-2010. It is believed that diesel vehicles will require advanced NOx and PM aftertreatment to be able to meet LEV II standards, but the technical feasibility of LEV II for diesels has not yet been demonstrated.
The ULEV II diesel Focus is equipped with a diesel particulate filter to control PM emissions and with a urea SCR (selective catalytic reduction) system for NOx control. The catalyst uses a water solution of urea injected upstream of the catalyst to reduce NOx.
To ensure that urea is always added to the vehicle, a process termed by Ford “co-fueling” is employed. Co-fueling fills the diesel and urea tanks at the same time through the use of a special fueling nozzle, so the operation is seamless for the customer. This fueling process has been developed and patented by Ford.
The ULEV II diesel Focus uses an advanced common-rail diesel engine with refined calibration. Ford said that testing results with the urea SCR NOx catalyst and particulate filter, combined with common rail diesel technology, indicate the diesel Focus vehicle will achieve ULEV II standards. Additional testing will be needed to confirm long-term durability. The LEV II emission durability requirement is 120,000 miles/11 years.
The LEV II regulation represent the most stringent emission standard worldwide. Numerical values of the standard are listed in the DieselNet Emission Standards section. Since the LEV II limits have been developed based on technical capabilities of gasoline engines and emission controls, they are extremely challenging for diesels in their NOx and PM parts, but relatively relaxed in regards to CO and NMOG (non-methane organic gases), as well as evaporative emissions.
Source: Ford Motor Company