Page 9 - pakoputkistot_pakettiautoille

DPF’s

Diesel particle filters (DPF) are closed
filters, that remove diesel particulate
mass (PM) & particulate number (PN);
also known as soot from the exhaust
gases. Diesel particle filters, in most cases,
work in strong connection with oxidation
catalyst. Usually the regeneration process
is controlled by ECU (engine control unit),
which measures back - pressure to get the
right data for regeneration. Regeneration
is ensured by an exhaust temperature of
around 300˚ - 400˚ degrees. Similar to
diesel oxidation catalysts, also for DPF
it is of high importance, which substrate
material is used, the amount of precious
metal coating, CPSI etc. All these factors
mentioned above have a high influence
to the back-pressure, regeneration
algorithm etc.

’

NO2 NO
CO2
’

PM

’

CO2

D’PF

• C + NO2 -> CO2 + NO (300˚C)
• C + O2 -> CO2 (600˚C)
• C = Soot

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