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Johnson Matthey Technology Puts World’s Cleanest Class 8 Diesel Trucks on Southern California Roads

LONG BEACH, CA – Older big-rig trucks now can have cleaner emissions than even the most modern clean diesel trucks. Johnson Matthey’s latest diesel emissions technology, the SCRT system, was unveiled in Southern California recently at the “Future Is Green” conference.

by Staff
October 7, 2008
3 min to read


LONG BEACH, CA – Older big-rig trucks now can have cleaner emissions than even the most modern clean diesel trucks. Johnson Matthey’s latest diesel emissions technology, the SCRT system, was unveiled in Southern California recently at the “Future Is Green” conference, an annual gathering of the California Air Pollution Control Officers Association, made up of air pollution fighters from throughout California. The event is hosted by the South Coast Air Quality Management District.

Johnson Matthey announced that a demonstration of its advanced diesel retrofit technology has been launched with a fleet of 16 older trucks owned by the Ralph’s supermarket chain in Southern California. Johnson Matthey and its partner, Cummins Emissions Solutions, retrofitted 16 older Class 8 grocery trucks used in the Ralphs’ delivery fleet with the new SCRT four-way control system. The trucks range in age from 1998 to 2004.

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The demonstration program involved a local partnership between Ralphs, the South Coast AQMD, and Johnson Matthey. Johnson Matthey will collect data on the vehicle’s emissions performance by measuring back pressure, temperature, and nitrogen oxides (NOx), a key smog-forming pollutant.

The four-way SCRT exhaust emission control system combines Johnson Matthey’s patented two-stage CRT particulate filter system (to reduce particulate matter by more than 85 percent) with a selective catalytic reduction (SCR) catalyst that reduces NOx by some 60 to 80 percent. It also reduces carbon monoxide (CO) and hydrocarbons (HC) by more than 90 percent. The result is a four-year-old truck with NOx emissions lower than those of a brand-new 2008 truck. The Ralphs trucks with this system could potentially remain in compliance with existing and proposed air quality regulations until 2020.

In a previous test using a similar fleet of grocery trucks in the Sacramento area, Johnson Matthey found that the SCRT system reduced NOx by an average of 84 percent compared to pre-retrofit levels. Those trucks had 2005 Cummins, 400-horsepower ISM engines with an EGR (exhaust gas recirculation) system. The ISM is a commonly used engine in Class 8 trucks hauling heavy loads.

At the “Future is Green” conference, Johnson Matthey also showed some of its technology being used on new vehicles, including a system used on the 2008 Dodge Ram pickup powered by a Cummins 6.7L turbodiesel that already meets emissions standards that take effect in 2010.

The next stage for this technology is verification by the California Air Resources Board and the U.S. Environmental Protection Agency, which is underway now. Johnson Matthey expects verification of the system by the end of 2008 or early 2009. The company has nearly 50 demonstration units running in California and Texas. After thousands of hours of operation, the SCRT system retrofits on both EGR and non-EGR engines has reduced NOx emissions by as much as 84 percent.

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