This paper describes the durability of the filtration layer integrated into Diesel Particulate Filters (DPFs) that we have developed to ensure low pressure loss and high filtration efficiency performances which also meet emission regulations.
DPF samples were evaluated in regards to their performance deterioration which is brought about by ash loading and uncontrolled regeneration cycles, respectively. Ash was synthesized by using a diesel fuel/lubrication oil mixture and was trapped up to a level which corresponded to a 240,000km run, into the DPFs both with and without the filtration layer. Afterwards, aged-DPFs were measured with respect to their permeability, pressure loss, filtration efficiency, as well as soot oxidation speed using suitable analytical methods.
Consequently, it has been confirmed that there was no noteworthy deterioration of the performances in the DPF with the filtration layer. On the other hand, the ash particles changed the performance of the filtration-layer-free DPF and gradually made it to act like the DPF with filtration layer.
Secondly, in order to confirm the thermal robustness of the filtration layer, uncontrolled regeneration tests were conducted, which were meant to simulate the worst case scenario regarding DPF operation. As a consequence of these tests, no deterioration of the filtration performance was observed and it can thus be assumed that the filtration performance will not be an issue with respect to Particulate Matter (PM) emission regulations.
Throughout these aforementioned tests, we were able to conclude that the developed filtration layer is sufficiently durable and maintains its performance.