Let\u2019s clarify the matter: petrol cars are equipped with trivalent catalytic converters, which reduce emissions of the three main components CO, HC and NOx.<\/p>\n
Euro 1-4 diesel engines on the other hand, use oxidation catalysts that can reduce CO and HC emissions, and NOx as well, but only to a lesser extent.<\/p>\n
Euro 5 regulations impose restrictions on the diesel particulate emissions so it was necessary to use anti particulate filters; Euro 6 has severe limits on NOx emissions as well, so they need to be equipped with SCR CAT and\/or Denox.<\/p>\n
For the above reasons, FAP filters are used on both Euro 5 and Euro 6 engines.<\/p>\n
A typical Euro 6 Diesel exhaust is equipped with a pre-cat, a post-cat, a ceramic FAP filter and an SCR using urea. Alternatively, a trap to cause a forced regeneration of NOx denox can be used.<\/p>\n
The reduction of particulate can then be obtained either with cordierite ceramic filters, or SIC or a different type of special metallic filter, where the gas is forced through a crisscrossed route, with particular spiral-shaped channels.<\/p>\n
The walls of each cell have micro-pores that act as filters for the dusts in the exhaust gas.<\/p>\n
The gas moves continuously from one cell to another, leaving more than 60% of particulate behind in the filter, and coming out cleaner.<\/p>\n
Compared to a ceramic FAP, metallic filters won’t force gas through the cell walls, so they \u00ec won’t oppose too much counter-pressure.<\/p>\n
Any time the pores of the walls are full, a slight increase in pressure occurs on the exhaust collector. Consequently, there is an increase in temperature, which triggers a regeneration, which in turn cleans the filter.<\/p>\n
From an Euro 5 and 6 regulations perspective, ceramic FAPs are unmatchable (they provide a 99.7% abatement of particulate), while the ceramic filter turns out to be the best compromise between limited emissions (reduced up to 70%) and a virtually unlimited life.<\/p>\n","protected":false},"excerpt":{"rendered":"
Both Euro 5 and Euro 6 are equipped with anti particulate filters. But what\u2019s the difference between ceramic and metallic FAPs?<\/p>\n","protected":false},"author":203,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[33],"tags":[],"yoast_head":"\n