A DPF is a device designed to remove diesel particulate matter (PM or soot) from diesel engine exhaust.

During operation, diesel engines produce a variety of PM due to incomplete fuel combustion. The composition of these particles varies widely – depending upon engine type, age, and the emissions specifications that the engine was designed to meet. The emitted particles in diesel exhaust can penetrate deep into the lungs - posing serious health risks including aggravated asthma, lung damage and other respiratory problems.

DPFs from CDTi typically remove more than 85% to 90% of the particulate matter found in diesel emissions.*

Diesel-powered vehicles that are equipped with a DPF emit no visible black carbon from the exhaust pipe and are far less harmful to the environment and the general health of people in the vicinity.

Historically, medium and heavy duty diesel engine emissions were not regulated until 1987 when the first California Heavy Truck rule was introduced capping particulate emissions at 0.60 g/BHP hour. Since then, progressively tighter standards have been introduced for both on-road and off-road diesel engines.

Two approaches to filter media regeneration

A DPF system collects the soot from the engine in the filter and then oxidizes, or "burns-off," the collected soot to effectively clean itself in a process called “regeneration”. Our DPF systems utilize two methodologies to regenerate (or clean) the filter media:

  • “Passive” Regeneration – the DPF uses heat generated by exhaust to oxidize soot and clean its own media
  • “Active” Regeneration – the DPF utilizes an outside energy source to heat the filter media and clean it

DPFs can also employ catalyst systems, to passively oxidize accumulated soot, and active regeneration strategies, where external energy sources are employed to initiate thermal oxidation.

We market both passively and actively regenerating DPF systems under the Purifilter®, Combifilter® and Cattrap® brand names.

Learn more about DPFs and other emissions controls technologies

If you would like to learn more about emissions controls technologies or have a specific application requiring DPFs or other improved emissions controls, please feel free to contact us.

*Current verified technology reduction values are dependent upon the specific engine type and application.