Starting from September 2018 the Euro 6c European emission standards, which reduces by ten times the emissions of particulates allowed for petrol cars and which was already in force for the newly approved models, is extended to all newly registered cars.
EURO 6 is an European standard about the reduction of pollutant emissions of light passenger and commercial vehicles in force from Sept. 2014 for new models and from Sept. 2015 for any vehicle.
EURO 6 concerns mainly the emissions of nitrogen oxides (NOx) which can affect the human breathing.
In order to reduce NOx emissions, manufacturers are adopting the SCR (Selective Catalyst Reduction) system, the efficiency of which has already been proven since this system has been used on trucks and heavy vehicles in general since several years.
DPF means Diesel Particulate Filter, a filter that is designed to remove diesel particulate matter or soot from the exhaust gas of a diesel engine but, unlike FAP technology, it does not use an additive during the regeneration.
DPF works at an higher temperature, 600-650°C, using a series of post-injections of fuel.
FAP is a particulate filter designed and patented by Citroën-Peugeot group which regeneration system is characterised by the using of an additive, cerium oxide.
The combustion of the PM10 naturally takes place at around 600-650°C but exhaust gas only reaches 200°C maximum. It’s necessary to raise the temperature with a post-injection of fuel: this is the moment when the cerium comes into play to lower the ignition temperature of the soot particles to 450°C, speeding up the regeneration and protecting the filter from a potential dangerous thermal stress.
During the combustion of fuels, the engine produces many exhaust soot particles which are harmful to the environment and to people’s health like carbon (CO), unburned hydrocarbons (UHCs), nitrogen oxides (NOx) and, in the case of a diesel engine, particulate matter (PM) which is smaller than about 10 micrometers, referred to as PM10.
Particulate filters are devices which trap PM10 (up to 99%) and, as any other filters, need to be cleaned out regularly to prevent the blocking and resulting damages to the car: an overfilled filter can damage the engine and can itself be damaged or destroyed.