Exhaust Gas Recirculation - EGR is a system that allows reintroducing in the cylinder a part of the exhaust gases, this way reducing pollution. The Euro 4 standard, which is to become compulsory, in October, can be respected with EGR.
Selective Catalytic Reduction - SCR technology has the property to reduce the unburned particles emissions and to transform the nitrogen oxides in the exhaust gas into nitrogen and water. The system uses in this purpose the AdBlue injection (AdBlue is a trademark for urea solution) into the catalytic converter. The pollution standard Euro 5 is being respected, in this way.
MAN has chosen to use both technologies on the same engine.
”EGR is a useful system for the small transport vehicles, in which any released space may be used to increase the storage capacity. Therefore, it proves its utility for those who are in charge of the freight. For the SCR, AgBlue addition is necessary, in contrast with the EGR case. Also, the SCR needs a big catalytic baffler“, says Rãzvan Manolescu, marketing manager Cefin Romania (an Iveco dealer).
DAF Company uses the SCR, as they consider it the most effective solution to their vehicles. “The SCR system provides a series of advantages, compared to the EGR one: “Throughout the EGR system the gases coming out from the engine are being reprocessed, which brings about the premature engine wear and the introduction of the impurities. That is not the case for the SCR system. In this case, fresh air enters the engine, a process which favors long-life”, explains Dan Pavãl, administrator at Eurospeed Suceava (a DAF dealer).
