Reducing NOx diesel emissions: US Pat. No. 7,644,579

U.S. Patent No. 7,644,579, issued on January 12, 2010 to Extengine Transport Systems, Inc. of Fullerton, CA, discloses a system to reduce the nitrogen oxide (NO_x) emissions from a diesel exhaust stream.

Diesel emissions include both nitrogen oxide (NO) and nitrogen dioxide (NO₂), which contribute to smog and acid rain and are classified as “toxic air contaminants” in California.  The patent discloses a system which injects ammonia (NH₃) into the exhaust stream to reduce these NO_x emissions, as well as reducing hydrocarbons, carbon monoxide, and particulate matter.  The system can be retrofitted onto existing diesel engines and does not incur a reduction of fuel efficiency.

According to their website, Extengine’s patented technologies and commercially-available exhaust after-treatment systems allow diesel fleet operators to be able to meet local, state, and federal air quality standards and mandates more quickly and cost effectively than by using other systems.  According to the USPTO assignment database, Extengine Transport Systems has three issued U.S. patents, including this one.