Exhaust aftertreatment


  • An exhaust gas treatment (NOx)is a procedure that purifies combustion gases , either mechanically or chemically, after they have left the combustion chamber.
  • Based on NOx-boundary values for diesel engines in diverse exhaust emission standards, a NOx-reducing exhaust  gas treatment is necessary in almost all vehicles.
  • Here the use of the SCR-converter (selective catalytic reduction) in combination with an aqueous urea solution (AdBlue) is applied in the exhast gas boxes.
  • By the injection of aqueous urea solution into the exhaust gas current,  the reducing agent ammonia is generated by hydrolysis.
  • In the SCR-converter nitrogen oxide (NO and NO2)  are converted into harmless nitrogen components.
  • The more evenly the ammonia is distributed in the exhaust gas, the more efficiently nitrogen oxide is reduced.
  • The two-phase flow simulation can be used as a tool for interpreting the exhaust gas boxes with SCR-converters and has been used successfully at ITB GmbH in prduct development for years.