Why 2013 is the Year of the Diesel



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Vic Kulihin

How Diesels Meet Emissions Standards

A. Engine
Diesel combustion creates two emission problems: particulate matter and nitrogen oxides (NOx ).

B. Particulate Filter
The particulate filter traps soot caused by incomplete combustion. The soot burns off eventually.

C. SCR Catalytic Converter
SCR uses an aqueous urea solution (aka diesel exhaust fluid, which is kept in an onboard tank) with a catalyst that reduces NOx to nitrogen, water, and carbon dioxide. Smaller engines can get by without SCR.