E&M U: Researchers Hunt Cure for 2007

U.S. diesel engine manufacturers pulled out all the stops to meet an accelerated deadline to Oct. 1 for cut-ting emissions of nitrogen oxides (NOx ) and hydrocarbons by 38%, but they barely have time to catch their collective breaths before they have to leap over the next hurdle.

Looming on the horizon is an even more rigorous reduced-emissions standard – cuts on the order of 90% -- with no obvious means of achieving that goal.

To reach the current target of 2.5 grams per brake horsepwoer-hour (g/bhp-hr) for combined NOx and nonmethane hydrocarbon (NMHC) emissions, four of the five engine makers relied heavily on exhaust gas recalculation, a technique that directs some of the oxygen-depleted exhaust gases back into the engine.

For the full story, see the December 2002/January 2003 issue of Equipment & Maintenance Update, which appears in the Dec. 23-30 print edition of Transport Topics. Subscribe today.

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