BlueTec 3673097 214435325 2008-05-23T15:20:10Z 64.238.172.212 /* Uses */ '''BlueTec''' is [[Daimler AG]]'s name for its two [[nitrogen oxide]] (NO<sub>x</sub>) reducing systems, for use in their [[Diesel]] [[automobile]] engines. One is a [[urea]]-based [[reductant]] called ''[[AdBlue]]'', the other is called [[NOx_Adsorbers|''DeNO<sub>x</sub>'']] and uses an oxidizing [[catalytic converter]] and [[particulate]] filter combined with other NO<sub>x</sub> reducing systems. Both systems are designed to reduce pollutant emissions. The BlueTec was on the [[Ward's 10 Best Engines]] list for 2007. ==Uses== [[Mercedes-Benz]] introduced the systems in the [[Mercedes-Benz E-Class|E-Class]] (using the 'DeNO<sub>x</sub>' system) and [[Mercedes-Benz GL-Class|GL-Class]] (using 'AdBlue') at the 2006 [[North American International Auto Show]] as the E320 and GL320 Bluetec vehicles. This system makes these vehicles 45-state and 50-state legal, respectively in the United States, and is expected to meet all emissions regulations through [[2009]]. A [[Jeep Grand Cherokee]] with the same BlueTec engine is also expected, and Mercedes announced tentative plans for a BLUETEC/electric hybrid [[Mercedes-Benz S-Class|S-Class]]. Daimler AG has entered into an agreement with [[Volkswagen]] and [[Audi]] to share BlueTec technology with them in order to increase the Diesel passenger-vehicle market in the [[US]]. [[Volkswagen]] introduced the [[VW Jetta|Jetta]] Clean [[Turbocharged Direct Injection|TDI]], the [[VW Tiguan| Tiguan]] concept, and the [[VW Touareg]] BlueTDI as part of the BlueTec licensing program. All are expected to be introduced in the American market in 2008. The [[Jetta]] and the [[Tiguan]] use [[NOx Adsorbers]], while the [[Volkswagen Touareg|Touareg]] uses a [[Selective Catalytic Reduction]] catalytic converter. In August 2007 VW Group announced that cooperation on BlueTec with Daimler AG would end. The reasoning for this change is due to the recognition of the VW TDI branding. VW did not want to use a competitors branding for a product they would introduce into the market. <ref>http://money.cnn.com/news/newsfeeds/articles/newstex/AFX-0013-18676102.htm</ref> ==Rationale== The BlueTec system was created because the processes that give diesel engines efficient fuel economy also creates extra emissions of certain pollutants. High [[compression ratio]]s and lean air-fuel mixtures make high combustion [[temperatures]], which results in more nitrogen oxides and [[Diesel Particulate Matter]] (also known as soot) being released into the [[Earth's atmosphere|atmosphere]]. While the particulate matter can be controlled with higher injection pressures and particulate filters, the big challenge is limiting NO<sub>x</sub> (Tier 2 regulations in the US are 0.05 grams per mile of NO<sub>x</sub>, which is ⅛ of the 0.40 limit in the [[European Union]]).<br /> Consisting of many different elements, BlueTec most notably relies upon particulate traps to eliminate soot/smoke throughout the engine's operating range, and upon urea injection from a stored canister (Mercedes calls this AdBlue) into the exhaust stream. AdBlue injection begins a chemical chain reaction which, in conjunction with an additional catalytic converter, converts nearly all remaining NOx into water vapor and nitrogen. ==Process== The BlueTec system will use two catalytic converters specifically targeting NO<sub>x</sub>. The first converter traps the NO<sub>x</sub>, and later releases it to the second converter which then converts it to [[nitrogen]] (N<sub>2</sub>) and [[Water (molecule)|water]] (H<sub>2</sub>O). This will make a diesel car legal in 45 states. But to make it pass the more stringent regulations of [[California]], [[Maine]], [[Massachusetts]], [[New York]] and [[Vermont]], ''AdBlue'' (NH<sub>4</sub>) will have to be introduced into the system, making the conversion more complete. :<math>NH_3 + NO_x \rightarrow \; N_2 + H_2O</math> The whole exhaust system would work like so: # A Diesel oxidation [[Catalytic converter|catalyst]] reduces the amounts of [[carbon monoxide]] (CO) and [[hydrocarbon]]s (HC) released from the exhaust. # A [[NOx_Adsorbers|DeNO<sub>x</sub>]] catalytic converter begins a preliminary removal of oxides of nitrogen. # A [[Diesel_particulate_filter|particulate filter]] traps and stores soot particles, burning them off when the filter gets full. # If the above are not sufficient to meet the exhaust specifications, a ''[[Selective Catalytic Reduction]]'' (SCR) catalytic converter will take the remaining nitrogen oxides and convert them to nitrogen and water. ''AdBlue'' will be injected into the exhaust gas stream to enable the conversion. == References == {{reflist}} == External links == * [http://www.bluetec.com BLUETEC.COM: The official BLUETEC News Blog by Mercedes-Benz] * [http://www.worldcarfans.com/classics.cfm/classicID/5061213.001/page/8/country/gcf/lang/eng/mercedes/the-evolution-from-diesel-to-bluetec-in-depth The Evolution from Diesel to BLUETEC in Depth] * [http://www.mercedes-benz.com/ Mercedes-Benz Global Home] * [http://www4.mercedes-benz.com/specials/scr/en/index_nocom_en.htm Official BlueTec website] * [http://www.greencarcongress.com/2006/01/daimlerchrysler.html greencarcongress.com on BlueTec] {{Volkswagen Group brands}} [[Category:Audi]] [[Category:Chrysler]] [[Category:Daimler AG]] [[Category:Volkswagen]] [[Category:Engine technology]] [[fr:BlueTec]]