The filtration system of water based solution plays a significant role in the process of cleaning DPF filters.
The DPF filter itself is and performs the function of a filter. Thus, the water based solution used to clean it must be free of dirt particles that could clog it.
The degree of accuracy and efficiency of particulate filtration varies between DPFs. Particulate filter parameters often depend on the exhaust emission standard that they had to meet during their application. In addition, they depend on the operating system.
The emission limit values for the heavy duty engines are 0.10, 0.05 or 0.02 g/bhp·hr since 2015 (NOx) and 0,005 g/km PM (solid particles)
Such restriction standards have forced OEM manufacturers to use increasingly better and more accurate DPF filters.
The porous walls of the filter brick (monolith) have a distribution of fine pores that are carefully controlled in the production process. The total porosity of the material is usually from 45 to 50% or more, while the average pore sizes are usually from 10 to 20 μm. The hydrodynamic method of cleaning DPF filters presses the water based solution from the outlet channels to the inlet channels through the porous walls dividing the filter channels. That is why the quality of water based solution is so important.
DPF filter cleaning machines operated in a closed circuit, which means that we use the same water based solution all the time in the cleaning process. Dirty water flowing out of the DPF during cleaning is filtered every time before refilling the filter over again.
When designing filter cartridges, we took into account not only the degree of accuracy in microns, but also its efficiency in percentage. On the market you can find filter cartridges that have a very good filtration accuracy of 1μm, but do not guarantee efficiency at a level greater than 20-30%.
OTOMATIC filter cartridges very effectively stop the smallest soot and ash particles, with a size several dozen times smaller than the size of a grain of sand.
OTOMATIC filter cartridges are distinguished by:
• filtration efficiency of 99.9% for particles with a size of just 3-5 μm
(1 micrometer = 1 thousandth of a millimeter)
• durable and ensuring tightness filter seals; we use filter gaskets of a unique polyurethane blend that is distinguished by its elasticity and resistance to compression at high temperatures;
• due to the unique properties of the gaskets, OTOMATIC filter cartridges maintain tightness in tanks during very hard operating conditions;
• OTOMATIC filter pleats are stabilized by means of special ribs that prevent adjacent pleats from sticking. The filtration process takes place over the entire surface of the filtration medium;
• Competitors offer filter cartridges at a level of 10 to 100 μm, or those with less than 50% efficiency, e.g. candle, bag or even string filters. This level of filtration does not guarantee effective cleaning of DPF filters.