AdBlue: an additive to pollute less
Keywords: pollution, reduction, NOx, nitrogen dioxide, anti-nox, denox.
In the same way as for passenger cars, trucks must comply with increasingly stringent anti-pollution standards. AdBlue technology enables diesel trucks to reduce their emissions to nitrogen oxides.
At a time when decision-makers - politicians or entrepreneurs - take greater account of the protection of the environment, it is appropriate to recall the requirements formulated by the Euro 4 emission standards applicable to heavy goods vehicles. From October 1, 2006, older generation engines will have to reduce their emissions by 30% (NOx-CO-HC). This implies a generalization of particulate filters on all vehicles.
To achieve this goal, two techniques are opposed. EGR (Exhaust Gas Recirculation) technology is used by manufacturers MAN and Scania. Part of the exhaust gas is cooled and returned to the engine in order to obtain a lower combustion temperature and complete the consumption of unburnt hydrocarbons (a lower combustion temperature reduces nitrogen oxide emissions and lower pressures. higher injection rates produce fewer particles).
According to the manufacturer GreenChem, the AdBlue would allow a reduction of consumption of the order of 5%
This technology allows the use of standard diesel fuel available at any pump, without having to worry about the availability of additives.
SCR (Selective Catalytic Reduction) technology concerns regions where the distribution infrastructure for the AdBlue product has been developed. Indeed, the SCR is a post-treatment method which requires the addition of this urea-based additive. AdBlue is injected into the exhaust to maintain a reaction in the catalytic converter, which is integrated into the muffler. This post-treatment method is used to reduce nitrogen oxides (NOx).
It may therefore be necessary to refuel AdBlue when the vehicle is refueled. The addition of an additional tank for AdBlue is therefore necessary.
The composition of AdBlue is made of 32,5% urea (CO2 and ammonia) and chemically pure water, which allows the exhaust gases to be reprocessed by converting approximately 85% of nitrogen oxides into vapor of water and nitrogen harmless to nature.
With AdBlue consumption of around 1,5l / 100 km for a vehicle meeting the Euro 4 standard, SCR technology allows a reduction of around 5% in average diesel consumption, thus covering the additional cost due to its use.
Founded in 2003, the Dutch company GreenChem (to which AdBlue belongs) plans to develop its distribution network and in particular the affiliated service stations. It is on this point that the shoe pinches.
Indeed, the first automated French station will finally see the light of day in Calais (Nord). But it will take a few more years for the whole of France to be covered ... and not all structures have the means to store containers on their site. Too bad, when we know that AdBlue is particularly well established among our neighbors.
Whatever the case, the main thing is to be able to envision a less “gray” future in transport. And this is the essential!
Author and Source: Julien Marcos