LOUISVILLE, Ky. – Tenneco says its after-treatment technologies, showcased at the Mid-America Trucking Show, can help engine and vehicle manufacturers achieve nearly 90-per cent reduction in emissions of fine particulate matter (PM) as mandated by the EPA beginning in 2007, and a similar reduction of nitrogen oxides (NOx) that will be phased in between 2007 and 2010.

Tenneco Automotive is working closely with several engine and vehicle manufacturers to develop and supply DOC and DPF systems which, combined with advances in engine design, will meet the new environmental requirements.

Beginning in 2007, the new standard will reduce the PM limit from 0.1 to 0.01 grams per base horsepower per hour. The NOx limit will drop from the current 2.0 g/bhp-hr to 0.2 g/bhp-hr between 2007 and 2010.

The Tenneco after-treatment solution includes Diesel Oxidation Catalyst (DOC) and Diesel Particulate Filter (DPF) units located within the vehicle’s exhaust system. A diesel oxidation catalyst, much like an automotive catalytic converter, uses precious metals to create a chemical reaction that breaks down pollutants into less harmful components. Tenneco’s DOC technology helps convert harmful NOx into nitrogen dioxide (NO2) while oxidizing absorbed hydrocarbons. This chemical reaction also acts as a combustor for unburned fuel that is re-circulated into the exhaust stream. These systems can be packaged to incorporate silencing devices, DPF and other NOx abatement technologies for optimum efficiency.

The Tenneco Automotive DPF, located downstream of the DOC, captures ash and other fine particulate matter by compressing, filtering and expanding the engine’s exhaust gasses. These filter systems are temperature resistant and eliminate more than 95 per cent of particulate matter from diesel emissions.

“It’s our goal to make exhaust after-treatment virtually transparent to the fleet and owner/operator,” said Lois Boyd, vice-president and general manager, commercial vehicle systems. “These technologies are designed to work in tandem with the next generation of diesel engines to ensure exceptional power, throttle response and engine reliability, yet with a mere fraction of the environmental impact common to current and older vehicles.”