DPF / FAP / KAT cleaning methods
Effective method of filter cleaning must clean the channels (inlet and outlet ones) of the filter from soot, ashes, carbon deposits, particulates of cerium oxide ad at the same time be safe for the filter core insert itself.
1. Hydrodynamic cleaning.
The cleaning method with the use of a specialist machine, forming the working jet of the fluid pointed directly at the filter inside. The application of a cleaning agent – a detergent is required.
Advantages : Safe for the filter catalytic coating. High effectiveness, even up to 99,5 % of capacity.
As one of the few it has a possibility of effective cleaning of the filter channels of all particulates: soot, ashes, carbon deposits, cerium oxide.
No necessity to cut out the ceramic insert.
Fast cleaning time of about 30 min.
Disadvantages : Effectiveness depends on well selected detergent.
2. Heat treatment
Curing soot in the induction furnace. Placing the ceramic insert of the filter core in the furnace for about 12 hours.
Advantages : Effectively removes (cures) soot.
Disadvantages : It does not remove the remaining particulates, e.g. ashes, which cannot be cured.
High risk of damaging the filter ceramic insert, sensitive to too rapid temperature changes.
Necessity to cut the filter, remove the insert and weld.
3. Ultrasonic treatment.
A method consisting in the full submersion of the filter in a bath with the solution. Ultrasounds in the washing solution form pressure waves in the form of the imploding bubbles, and these in turn tear off contaminations from the surfaces of the filters being washed.
Advantages : It enables good cleaning of the filter channels as long as water reaches all places.
No necessity to cut the filter.
Disadvantages : In the case of very blocked (cured) filter channels water with ultrasounds has limited access and a possibility of penetration. Leaving those places blocked.
It requires blowing with compressed air.
4. Pneumatic treatment.
The particulate filter is placed in the specialist machine in which it undergoes blowing with compressed air.
Advantages : Each filter channel is dealt with individually during blowing.
Relatively non-invasive for the filter insert.
Cleaning without a detergent.
Disadvantages : The need to cut the filter, remove the insert, weld.
Not very effective in the case of the filter insert flooded with oil.
General effectiveness at the level 70 %.
5. Curing in the service mode.
By means of a diagnostic computer a mode is launched in which the engine operates on high speed.
Much richer fuel mixture influences an increase in the temperature of exhaust fumes even to the level of up to 600 degrees! In such conditions it is possible to cure soot.
Advantages : Effectively cures soot in the vehicles with low mileage to 50.000 km.
The procedure with the filter disassembly.
Disadvantages : It does not remove ashes. It only cures soot.
Not really effective in the case of cars with high mileage, where the level of ashes is the majority of the blocked filter.
The service mode of regeneration overloads the engine ( damaging the engine).
Necessity to change oil.
6. Chemical treatment.
The activity consists in inserting special chemicals inside the filter to dissolve soot. Chemical treatment of carbon deposits with one preparation, and then flushing them with the other. Then, a mechanic connects the car with the service computer and initiates the service procedure of the filter regeneration.
Advantages : It does not require cutting the filter. Application of chemicals without the filter disassembly.
Disadvantages : It washes away only the smallest particles in inlet channels of the filter insert.
Effectively cleans only outlet channels of the filter, leaving dissolved deposits in inlet channels (blinded from the outlet side).
A method very invasive for the filter insert.