Engines now employ a range of technologies to lower emissions and increase performance and efficiency including new combustion chamber designs, advanced electronic fuel injection systems, turbocharging systems, exhaust gas recirculation, oxidation catalysts, particulate filters, and use of reduced sulfur clean diesel fuel.
Of the five major emissions from internal combustion engines—carbon monoxide, hydrocarbons, carbon dioxide, nitrogen oxide, and particulate matter—diesel emits only a small amount of the first three. The industry has focused on reducing particulate matter (PM) and nitrogen oxides (NOx). The white paper says particulate matter emissions from all new on-highway diesel engines built since 1988 have been reduced 83%. Emissions of nitrogen oxides have been reduced by 63% since 1988. New engine standards for 2004 will cut NOx emissions in half again, resulting in a total NOx reduction of 83% since 1988.
Adopted in February 2001, the 2007–2010 Environmental Protection Agency regulations will require use of cleaner diesel fuel to enable further lowering of NOx and PM—reducing these emissions by as much as 98% from the 1988 levels.
The white paper:
•Explains inherent performance advantages of diesel.
•Provides an emissions profile of diesel as the starting point for emissions reduction.
•Documents major emissions reductions that have been made to date.
•Describes the technologies that will be employed over the next decade to achieve the virtual elimination of key pollutants.
Copies of “Engineering Clean Air” can be downloaded from www.dieselforum.org or obtained by phoning 703-234-4411.