Detroit Diesel Unveils SCR Equipment, Projects Improved Fuel Economy
April 1, 2009
ORLANDO, Fla. - Detroit Diesel has unveiled equipment that will leverage Diesel Exhaust Fluid (DEF) to meet the next round of exhaust emission standards -complete with a claim that it will improve fue...
SNEAK PEAK: Trucking journalists got their first look at this Detroit Diesel EPA2010-compliant SCR system at a recent press event.
ORLANDO, Fla. –Detroit Diesel has unveiled equipment that will leverage Diesel Exhaust Fluid (DEF) to meet the next round of exhaust emission standards -complete with a claim that it will improve fuel economy in the process.
The new BlueTec system, based on technology that is already being used in Europe, will comply with the US Environmental Protection Agency’s 2010 emission standards and introduce truckers to a new tank that needs to be filled with a premixed solution of two-thirds water and one-third urea.
In addition to the 23-gallon tank, the 382 lbs of equipment includes a doser, a catalyst, and an Aftertreatment Control Module to help limit the output of smog-forming nitrogen oxide (NOx). Drivers will be able to monitor the fluid levels with a simple series of lights at the bottom of the fuel gauge.
Before the red warning light appears, they will need to top off the tank that is identified by a bright blue cap.
Otherwise, the engine’s power will be automatically “de-rated” by about 25%, says Rakesh Aneja, EPA 2010 program manager.
A restrictor has also been introduced at the mouth of the tank to prevent drivers from mistakenly inserting the nozzle from a diesel fuel island. And the related labels are expected to discourage people from mistakenly adding jugs of other common fluids such as coolant or windshield washer fluid.
“Based on what we’ve seen among truck drivers running SCR trucks in Europe, and what we hear from our customer fleets, no-one expects topping off with Diesel Exhaust Fluid to be a problem – especially when you only have to do it every 5,000 to 7,000 miles,” said Michael Jackson, general manager, marketing, Daimler Trucks North America.
“In some longhaul applications with BlueTec SCR, a customer could travel up to four tankloads of diesel fuel before having to refill a 23-gallon DEF tank.”
“Some non-SCR proponents have stated publicly that you can’t trust a truck driver to fill Diesel Exhaust Fluid tanks. This seems odd, because we clearly trust drivers to put fuel in tanks and Diesel Exhaust Fluid will become just as routine,” he added.
An unexpected key to the announcement is that Detroit Diesel expects the technology to improve fuel economy by up to 5%, with net savings reaching up to 3% once the new fluid is included in the calculations. In a linehaul application, that could save about 800 US gallons of fuel per year, while consuming about 300 gallons of the new mixture of urea and water.
The average regeneration interval for a Diesel Particulate Filter, introduced during the last round of emission standards, will extend to more than 2,000 miles, using about two gallons of the fluid each time.
The systems will be offered in a single-box design, which will be used by most customers, or will be included in two boxes that split the SCR aftertreatment equipment from the Diesel Oxidation Catalyst and the Diesel Particulate Filter. The latter designs will be needed to accommodate applications such as twin-steer equipment.
The single-box designs are expected to offer the best fuel economy because they produce lower back pressures than their two-box counterparts.
Related changes to the timing of the fuel injection is also expected to lower heat rejection and the related stress on the cooling system, since the exhaust treatment will occur outside of the engine compartment.
BlueTec will be included on the DD13, the big bore DD15 and the upcoming DD16, in the Freightliner Cascadia and a soon-to-be launched new generation of classic and vocational trucks. Western Star trucks will also be equipped with the system.
By 2010, the company expects it will have recorded 25 million miles of testing. BlueTec has already been used in Europe since 2005, while EGR has been used by Detroit Diesel since 2000. •