Truckers in Texas, as well as across the country, understand that being a trucker is a lot more than just knowing how to drive. It includes knowing the basics of various systems in the truck and how to reduce wear and tear and the cost of repairs. One system that truckers need to understand is DPF operation and DPF cleaning.
DPF Basics
DPF or diesel particulate filtration is designed to capture and hold the soot particles that are produced in a diesel engine. This is completed in the exhaust, and the DPF will actually hold those particles, which are in a solid form until they are burned or oxidized. This entire process is known as regeneration.
The most common type of filter looks like a honeycomb and is made of a ceramic material. The ends of alternating channels of the honeycomb pattern are closed, which creates the movement of the particulate containing exhaust through the filter walls to trap the soot. The gas from the exhaust is small enough to pass through the walls of the filter.
Ceramic materials used in DPF filters, including silicon carbide, cordierite and aluminum titanate. These materials can withstand very high heat, which makes them highly effective but also very long lasting.
DPF Cleaning and Regeneration
With regeneration, the layer of soot that accumulates is burned off. The temperature this process occurs at is about 1,000 degrees Fahrenheit, which is why a diesel burner and a diesel oxidation catalyst is usually required to boost temperatures to this level in a process known as active regeneration. This process typically takes about 30 minutes and can be done while operating the vehicle.
Passive regeneration can also occur in the presence of NO2 without additional heat. This requires that nitrous oxide is present, and this can be supplied in the form of a catalyst that uses specific types of precious metals to create the necessary conditions.
While both active and passive regeneration will burn off the soot, it leaves another by-product. This is known as ash, and it cannot be removed other than through DPF cleaning.
There are several factors that will impact the DPF cleaning process. This can include the type of engine oil used and even the quality of ash in the filter. Cleaning services will inspect the filter, determine the level of soot and ash, and then choose the appropriate process. This will typically include both burning off existing soot and then using pneumatic and other treatments to effectively remove the ash build up, allowing the filter to function effectively again.
