18 February 2006

DaimlerChrysler has announced that the 10,000th truck with the BlueTec diesel technology has recently come off the line at the truck plant in Wörth, Germany. The milestone Mercedes-Benz Actros BlueTec 5 model was handed over to the management of freight company GRT Wittwer Transport GmbH by Hubertus Troska, Head of the Mercedes-Benz Trucks Business Unit.

The BlueTec technology—based on selective catalytic reduction (SCR) of NOx using urea—was launched by DaimlerChrysler one year ago. DaimlerChrysler BlueTec trucks meet Euro V (2008/9) emission standards (NOx = 2 g/kWh). The early introduction of Euro V engines is stimulated by German road toll concessions.

According to GRT Wittwer Transport, BlueTec diesel technology brings fuel savings of between 1,500 and 2,000 liters of diesel a year in long-haul operation (however, the overall savings are offset to some degree by the cost of urea solution, AdBlue). The high efficiency is possible as the engines can be calibrated for advanced combustion, and the resulting increased NOx emissions are reduced in the SCR system. The BlueTec diesel technology won DaimlerChrysler the German “Golden Oil Drop 2005” award.

Other advantages of the urea-SCR technology emphasized by DaimlerChrysler include unchanged service intervals of up to 150,000 km and improved fuel quality tolerance, including the tolerance of high-sulfur diesel.

Mercedes-Benz trucks, launched just under a year ago, were the first commercial Euro V vehicles. Starting with the Mercedes-Benz Actros heavy-duty trucks, BlueTec has now also been introduced in the Mercedes-Benz Axor and Mercedes-Benz Atego truck ranges. With 10,000 vehicles, Mercedes-Benz accounts for approximately two thirds of the Euro IV/V trucks currently operating in Europe. Around 98% of Mercedes-Benz truck orders are for the Euro V version.

The BlueTec diesel technology is based on improved engine design combined with exhaust aftertreatment. Particulate matter emissions are controlled in the engine cylinder—the BlueTec trucks are not fitted with diesel particulate filters. NOx emissions are controlled using aqueous urea solution (AdBlue) as a reducing agent, which is injected upstream of the SCR catalyst.

According to DaimlerChrysler, there are now about 1,500 public-access AdBlue refuelling sites in Europe.

DaimlerChrysler has been one of the main advocates of using SCR-based BlueTec technology to meet Euro IV/V standards, and as a basis for meeting future more stringent European emission standards. All European manufacturers have been developing Euro 5 technologies based on SCR. However, a number of Euro IV (2005/6) engines—such as those by MAN or Scania—are based on exhaust gas recirculation (EGR) technology, rather than SCR.

Urea-SCR trucks have also been launched in Japan (Nissan Diesel Quon heavy-duty truck, November 2004). Urea-SCR remains a serious candidate technology for US 2010 truck and bus engines.

Source: DaimlerChrysler