Soot catcher

After pre-treatment in an upstream oxidizing catalyst, exhaust gas passes through the diesel particulate filter (DPF) where particulate matter (soot) is captured and held in a honeycomb cell structure. To keep the system working optimally, the DPF goes through periodic automatic regeneration. The onboard computer controls fuel injection to allow unburned fuel to enter the filter at measured intervals where it flares off and generates increased temperatures that incinerate the accumulated soot. The resulting expelled exhaust gas has a 93-percent soot reduction and a 50-percent NOx reduction.

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