BOSCH 0 444 025 029 Dosing Module, urea injection

Description

Function:

• The Dosage Module is responsible for injecting a specific solution called AdBlue (also known as Diesel Exhaust Fluid or DEF) into the exhaust system.
• AdBlue is a non-toxic, water-based solution containing urea. During the SCR process, the hot exhaust gases pass through a catalyst coated with specific metals. The injected AdBlue decomposes into ammonia (NH3) in the presence of the hot catalyst.
• This ammonia then reacts with nitrogen oxides (NOx), a harmful pollutant present in the exhaust gases, converting them into harmless nitrogen (N2) and water (H2O) through a chemical reaction:
  • 4NO + 4NH3 + O2 -> 6N2 + 6H2O

Dosage Module Components:

• Pump: This component draws AdBlue from the dedicated tank in the vehicle.
• Injection nozzle: This sprays the AdBlue solution into the exhaust system at a precise location and in a controlled manner.
• Control unit: This electronic unit receives signals from the engine management system and controls the pump and injection based on engine operating conditions and emission requirements.

Importance:

• The Dosage Module plays a crucial role in reducing NOx emissions from BMW diesel engines, contributing to cleaner air and compliance with stringent emission regulations.
• By accurately metering and injecting AdBlue, the Dosage Module ensures optimal performance of the SCR system and minimizes the environmental impact of the vehicle