Just as a whole batch of new fifty state-legal diesel vehicles are about to hit the market in the U.S., chemical company BASF is set to take advantage of the situation. BASF has announced that they will be raising the price of AdBlue by €45 per 1,000 liters. AdBlue is the 1/3 urea, 2/3 water solution used for the NOx after-treatment system in new diesel engines. The urea solution is injected into the exhaust gas stream where the heat of the exhaust causes it turn into ammonia by a hydrolysis reaction. The ammonia reacts with the exhaust in a special catalyst to turn the NOx into nitrogen and water.

The only reason for using the urea solution instead of straight urea is to allow for more precise dosing so that it lasts longer and no excess is used and passed through the exhaust. The Mercedes and BMW vehicles that are coming to market with urea injection systems that hold about 4-5 gallons of AdBlue which needs to be replenished every 15,000 miles or so. BASF claims the price increase is due to tight raw material supplies and the need to ensure product quality.

[Source: BASF]

We and our readers are familiar with urea injection system thanks to Mercedes' BlueTec technology (aka CleanTDI at Volkswagen). Until now, these systems had been announced in passenger vehicles geared to the US market but the city of Málaga (Spain) has announced that it's purchasing one bus equipped with this urea injection technology aimed to reduce NOx emissions. Until now, news about clean diesels in Europe featured DPF (Diesel Particullate Filters) and little about these urea injection devices.

The vehicle (its manufacturer has not been announced) has a cost of 220,000 EUR and it's supposed to reduce pollution from the tailpipe by 20 percent when compared to current offerings in the public bus market. Málaga's bus company has also the ISO 14000 environmental certification and is also running its vehicles with biodiesel, consuming 1.1 million liters in 2006. To further the environmental initatives of the company, plans have been announced to add a CNG fleet by the end of 2008.

Do any of our readers know if a system like this is being used by other bus companies in Europe?

Related:

• Public bus fleet announces reduction in biodiesel blend
• Iveco sells 3900th CNG bus in Europe
• Ann Arbor, MI switching entire bus fleet to hybrids

[Source: Europa Press]

It looks like Mercedes won't be the only car-maker using urea injection to help their diesel engines meet tough new US emissions standards. The problem that all car-makers have with diesels is nitrogen oxide emissions. In order to minimize unburned hydro-carbons and fuel consumption all engines (gas and diesel) have been moving toward leaner fuel-air mixtures and one side-effect of this is extra nitrogen oxide production. One way to get around that is to expose the exhaust to ammonia. This causes the nitrogen oxides to convert to water vapor and nitrogen gas. Injecting an aqueous urea solution known as AdBlue, provides the necessary ammonia. This system was developed by Mercedes-Benz and Bosch and commercialized under the name BlueTec. Mercedes already announced their intentions to sell a 50 state legal BlueTec system in 2008. Now they have reached an agreement with Volkswagen group to use BlueTec on VW and Audi diesels and are close to finalizing a deal with BMW as well. It's great that DaimlerChrylser has chosen to share this technology, because diesels are an important step to reducing fuel consumption and in turn greenhouse gases. The only problem with the BlueTec solution is the need to replenish the urea supply periodically. The three car makers are all planning to show BlueTec equipped diesel vehicles at the Los Angeles Auto Show in December. VW will be showing their new Tiguan compact SUV, and Audi Q7, BMW will have the diesel version of the new X5, and Mercedes will have the R, ML and GL class diesels.

[Source: GreenCarCongress.com]