Diesel particulate filter system

Diesel particulate filter system

The direct injection diesel engine generation, called HDi (High pressure Direct Injection), has the main advantage of a 20% reduction in carbon dioxide (CO2) emissions by comparison with a conventional indirect injection diesel engine, but also a reduction in carbon monoxide (-40%), hydrocarbon (-50%) and particulate (-60%) emissions.

Fitted with a particulate filter (DPFS), the HDi DPFS engine is designed to eradicate emissions of polluting soot particulates (black smoke). How does it work?

Stage 1: filtration

This first stage involves restraining the soot particulates in a silicon carbide filter having a porous structure.

Stage 2: elimination of particulates

Next, the elimination of soot particulates takes place during the regeneration stage. This regular operation (after a few hundred kilometres) is automatic and imperceptible by the driver. It quite simply involves burning, at very high temperature, the soot particulates accumulated in the filter.
This sequential regeneration takes place through the combined action of:
- the Common Rail system which performs post-injection of fuel to promote an increase in the exhaust gas temperature so as to move closer to the temperature of combustion of the soot particulates, and
- additive which is added automatically in very small quantities to the diesel fuel tank and which has the effect of lowering to 450°C the temperature required for soot combustion. This additived DPFS technique, unique in the world, means that Peugeot vehicles eradicate particulates reliably over time.

The frequency of filter servicing has gone gradually from once every 80,000 km to once every 120,000 km and now exceeds 180,000 km due to successive optimisation of the filter and additive.