Passive regeneration in a DPF

Passive regeneration is an approach used to oxidise particulate matter (PM) in the diesel particulate filter (DPF). In contrast to higher temperature active regeneration, passive regeneration uses normal exhaust temperatures and nitrogen dioxide (NO2) as the catalyst to oxidise PM in the DPF. Operators benefit from the simplicity of the passive regeneration process, and fewer components make it a lightweight and easily installed solution.

In contrast to higher temperature active regeneration, passive regeneration – sometimes referred to as ‘passive regen’ – uses normal exhaust temperatures and nitrogen dioxide (NO2) as the catalyst to oxidise PM in the DPF.

What does a DPF do?

EU Stage IV/U.S. EPA Tier 4 Final emission standards have reduced the amount of PM or soot entering the atmosphere by up to 98 percent when compared with emissions from non-regulated engines. Ultra-fine particulates pass through and are captured by the DPF. This achieves the required reduction without compromising machine reliability and productivity. Over time, these particulates build up.

Passive regeneration helps to reduce engine emissions

To maintain the performance of the DPF, passive regeneration is used to oxidise the PM within the filter. It’s a continuous process that allows the DPF to perform as intended without the need to raise the temperature.

What are the strengths of passive regeneration?

  • It’s a simple solution invisible to the operator
  • Perkins Passive Regeneration DPF systems are designed to be service free, and fit for life
  • Fewer components make it a lighter weight solution for your machines
  • It eliminates downtime compared with some active systems that may require a machine to be out of action during cleaning or maintenance
  • By eliminating the need for raised temperatures, passive regeneration is suitable for all working environments

Is passive regeneration used for all engines?

Passive regeneration occurs, to some extent, in all DPF systems. Perkins has engines are available that are passive only – so there’s no need for any active system.

If you’re looking for a simple solution that is invisible to the operator, passive regeneration is a logical choice. There are no extra lights or controls to increase the operator’s workload. It’s a continuous process, allowing the DPF to perform as intended. And with Perkins offering service-free systems, operators won’t have to worry during the life of the machine.

A DPF system utilizing passive regeneration delivers reliable operation over a wide variety of applications and duty cycles. Out in the field or on site, that means excellent fuel consumption,no disruption to the operator, no downtime and, therefore, increased productivity for the operator.


Fast facts

Passive regeneration:

  • Uses normal exhaust temperatures and NO2 as the oxidant to oxidise soot
  • Is invisible to the operator, making it a simple solution

1200 Series

1200 Series

The 1200 Series industrial and electric power engines are designed to operate around the clock, in whatever environmental conditions you choose.

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Cleaning your particulate filter

Cleaning your particulate filter

Cleaning of the DPF, which removes soot and other build-up from your engine, should be carried out at specified intervals as part of your routine maintenance programme.

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