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Truck using Diesel Exhaust Fluid

Truck using Diesel Exhaust Fluid

SCR Technology

What is Selective Catalytic Reduction (SCR) technology for on-road and off-road diesel powered vehicles?

Diesel Exhaust Fluid is combined with SCR technology.  SCR stands for an after treatment technology called Selective Catalytic Reduction. This technology requires the use of an operating fluid known as Diesel Exhaust Fluid (DEF) to reduce the Nitrogen Oxides (NOx) in the emissions.  Almost all major diesel engine manufacturers have decided to use this SCR technology to meet the new emission regulations on NOx reduction. SCR is the most cost effective solution to meet NOx emission standards of the EPA Clean Air Act.

The main components of the SCR system are the SCR catalyst, the Diesel Exhaust Fluid injection unit, the Diesel Exhaust Fluid tank and the DEF dosing control unit. Diesel Exhaust Fluid is injected into the exhaust pipe, in front of the SCR catalyst, downstream of the engine. The heat of the engine exhaust gases decomposes DEF into ammonia.  When the NOx reacts inside the catalyst with the ammonia, the harmful NOx molecules in the exhaust are converted to harmless nitrogen and water.

For the correct functioning of your SCR system, make sure you use only high quality Diesel Exhaust Fluid (DEF) such as Air1®.  Poor quality DEF that is contaminated with foreign matters risks damaging your catalyst.

SCR is a proven technology and one which will be relied on in the future.