24 May 2008
Southwest Research Institute (SwRI) of San Antonio, TX announced a cooperative research program to develop accelerated aging procedures for diesel emission systems and components. The effort will seek to provide common procedures for use by industry in general, and to potentially simplify emission certification procedures for diesel vehicles in the United States.
The consortium, Diesel Aftertreatment Accelerated Aging Cycles (DAAAC), intends to develop standard accelerated aging procedures for diesel emission systems for use in the same way as those the Environmental Protection Agency (EPA) has adopted for gasoline vehicles. Currently, the EPA requires diesel vehicle manufacturers to drive vehicles for 120,000 miles with periodic emissions measurements to certify the vehicles for sale. Gasoline vehicle manufacturers, however, can replace actual driving with an accelerated aging procedure—a standardized bench cycle—providing for significant savings in both time and expense to meet certification requirements.
At an SwRI symposium in February, representatives from 35 companies and organizations agreed that the consortium should develop aging procedures for EPA vehicle certification. They also recommended developing procedures for heavy-duty diesel emission components and systems that can be used generically apart from any regulated procedures. In the first year of the two-year consortium, members will work on single-component aging procedures to identify the simplest effective procedures. During the second year, members will develop procedures for vehicle certification and for heavy-duty emission system applications.
In developing the procedures, at least four different aftertreatment systems will be considered: the diesel oxidation catalyst (DOC), the diesel particulate filter (DPF), the NOx adsorber catalyst (NAC) or lean NOx trap (LNT), and the urea (ammonia) selective catalytic reduction catalyst (SCR).
Members will have access to all information developed during the consortium activities, and will be able to use the developed procedures, whether or not they are published and written into the regulations. The DAAAC consortium kick-off meeting is scheduled on June 13. For more information visit www.daaac.swri.org or contact Dr. Gordon Bartley.