Selective Catalytic Reduction in Diesel Engines
Selective catalytic reduction (SCR) is an advanced emissions control technology used in diesel engines to reduce nitrogen oxides (NOx) emissions.
This process involves injecting a urea-based solution, commonly known as diesel exhaust fluid (DEF), into the exhaust stream. The DEF reacts with NOx in the presence of a catalyst, converting these harmful emissions into nitrogen (N₂) and water (H₂O), which are harmless to the environment.
SCR systems typically consist of a catalyst, a mixing chamber, and a DEF injection system. When the exhaust gases pass through the SCR catalyst, the urea decomposes into ammonia (NH₃), which then reacts with NOx to form nitrogen and water. This reaction is highly efficient, achieving NOx reduction rates of up to 90% in some applications. As a result, SCR technology has become a standard feature in many modern diesel vehicles, helping manufacturers comply with stringent emissions regulations.
One of the challenges associated with SCR…