Regeneration of the DPF – DET’s Smarttrap™
How DET's SmartTrap works (Click here)
DET has developed its own range of Active DPf’s, these Smarttraps™ use various regeneration processes for the accumulated soot from the filter. This is done using our on-board active filter management system which has the ability of using a variety of strategies: (The same Smart Controller also offers features for Nox abatement devices.)
- Engine management to increase exhaust temperature
- A catalytic oxidizer to increase the exhaust temperature after injection (HC-Doser)
- Resistive heating coils to increase the exhaust temperature
 Our on-board active systems use extra fuel through burning to heat the DPF, or provide extra power to the DPF's electrical system. The Smarttrap™ Controller monitors one or more sensors that measure back pressure and/or temperature. Based on pre-programmed logic and set points, the controller makes decisions on when to activate the regeneration cycle based on these pre-defined points. The additional fuel required is supplied by a metering pump and is in turn atomized through our injector. Running the cycle too often while keeping the back pressure in the exhaust system low will use extra fuel. The reverse runs risk of uncontrolled regeneration and possible DPF failure. The Smarttrap™ controller has been developed to minimize failure of any type.
 Diesel particulate matter combusts when temperatures range between 400 and 600 ° Celsius. The start of combustion causes a further increase in temperature, and in some cases, the combustion of the particulate matter can raise temperatures above the structural integrity threshold of the filter material. This can cause catastrophic failure of the substrate due to exothermic reactions. DET has developed a strategy to limit this possibility. Note that unlike a spark-ignited engine (gasoline engine), which typically has a lambda value (pre-filter percent oxygen in gas stream) of less than 0.5% oxygen in the exhaust gas stream, many diesel engines run above 15% oxygen pre-filter / catalyst. While the large amount of available oxygen makes fast regeneration of a filter possible, it also contributes to runaway regeneration problems but again DET has a safety program included within all their smarttrap™ Controllers.
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