Particulate filters are used to reduce emissions produced by Diesel engines. They filter soot and unburned hydrocarbon particles, in order to turn them into the much more environment-friendly CO2. There are closed and open filtering systems. The former come already fitted in, while open particulate filters must be added on. The difference consists in the fact that in closed systems, the exhaust particles do not stream through a filter but they collect, instead, in a fleece. However, the level of efficiency is in this case more limited. While in closed filtering systems a sensor transmits information about the state of the filter to the control unit, and the exhaust particles are, therefore, burnt off as required, in open filtering systems, the burning off process takes place automatically every 500 to 1,000 Km. This is only possible, though, when the vehicle reaches a certain temperature, for instance, when travelling on a motorway. Therefore, regeneration cannot occur in city traffic, since under these conditions a temperature of barely 200°C (Celsius) is attained.
Clogged Diesel particulate filters: to swap or to clean?
When the particulate filter is clogged, it must be either cleaned or swapped. In the case of Diesel built-in filters, very often, when approaching the approximate 150,000 Km boundary, the self-cleaning process gets impaired because the by-product ashes clog the filter. The driving performance is, thus, considerably affected. Cleaning is about half the price cheaper compared with the fitting in of a new filter, which is worth around 4,000 AED. There are several cleaning procedures that aim at restoring a filter’s functioning. According to the thermal-mechanical method, filters are slowly heated inside a sort of kiln (regenerator machine) and subsequently left to cool down, carefully removing the ashes through carbon dioxide and compressed air. The chemical method, instead, entails the use of cleaning solutions and a steam-jet blaster. After the cleaning, the filter will perform almost as good as new.
Adding on particulate filters
Fundamentally, any vehicle, which operates with a Diesel engine can be eligible for particulate filter fitting. Specialist garages may charge from 2500 AED to more than 4,000 AED. The adding on of a particulate filter presents the advantage that the vehicle is better for the environment.