BlueTec
Encyclopedia
BlueTec is Daimler AG's marketing name
for engines equipped with advanced NOx
reducing technology for vehicle emissions control in diesel
-powered vehicles. The technology in BlueTec vehicles includes a selective catalytic reduction
(SCR) system that uses diesel exhaust fluid, and a system of NOx Adsorbers
the automaker calls DeNOx, which uses an oxidizing catalytic converter
and diesel particulate filter
combined with other NOx reducing systems.
The BlueTec was on the Ward's 10 Best Engines
list for 2007 and 2008.
(using the DeNOx system) and GL-Class
(using SCR) at the 2006 North American International Auto Show
. At that time, these BlueTec vehicles were 45- and 50-state legal, respectively, in the United States (a 45-state vehicle does not meet the more stringent California emission standards that have also been adopted by four other states).
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 United States. VW introduced the Jetta
Clean TDI
, the Tiguan
concept, and the Touareg
BlueTDI as part of the BlueTec licensing program. The Jetta and the Tiguan use NOx adsorber
s, while the 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 competitor's branding for a product they would introduce into the market.
By 2010 a BlueTec version of the Mercedes Sprinter
was released. The BlueTec systems allowed the elimination of much of the EGR in that vehicle's engine, which as a result gives 188 HP compared to the non-BlueTec engine's 154 hp.
that give diesel engines high fuel efficiency also lead to relatively higher emissions of certain pollutants compared to Otto cycle
engines. High compression ratio
s and lean air-fuel mixtures make high combustion temperature
s, which results in more nitrogen oxides being released into the atmosphere
. While the particulate matter can be controlled with higher injection pressures and particulate filters, the big challenge is limiting NOx; Tier 2 regulations in the US are 0.05 grams per mile of NOx, which is ⅛ of the 0.40 limit in the European Union
.
Brand
The American Marketing Association defines a brand as a "Name, term, design, symbol, or any other feature that identifies one seller's good or service as distinct from those of other sellers."...
for engines equipped with advanced NOx
NOx
NOx is a generic term for the mono-nitrogen oxides NO and NO2 . They are produced from the reaction of nitrogen and oxygen gases in the air during combustion, especially at high temperatures...
reducing technology for vehicle emissions control in diesel
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...
-powered vehicles. The technology in BlueTec vehicles includes a selective catalytic reduction
Selective catalytic reduction
Selective catalytic reduction is a means of converting nitrogen oxides, also referred to as with the aid of a catalyst into diatomic nitrogen , , and water, . A gaseous reductant, typically anhydrous ammonia, aqueous ammonia or urea, is added to a stream of flue or exhaust gas and is absorbed...
(SCR) system that uses diesel exhaust fluid, and a system of NOx Adsorbers
NOx Adsorbers
A NOx adsorber or NOx trap is a device that is used to reduce oxides of nitrogen emissions from a lean burn internal combustion engine.-Purpose and function of a NOx adsorber:...
the automaker calls DeNOx, which uses an oxidizing catalytic converter
Catalytic converter
A catalytic converter is a device used to convert toxic exhaust emissions from an internal combustion engine into non-toxic substances. Inside a catalytic converter, a catalyst stimulates a chemical reaction in which noxious byproducts of combustion are converted to less toxic substances by dint...
and diesel particulate filter
Diesel Particulate Filter
A diesel particulate filter is a device designed to remove diesel particulate matter or soot from the exhaust gas of a diesel engine. Wall-flow diesel particulate filters usually remove 85% or more of the soot, and under certain conditions can attain soot removal efficiencies of close to 100%...
combined with other NOx reducing systems.
The BlueTec was on the Ward's 10 Best Engines
Ward's 10 Best Engines
Ward's 10 Best Engines is an annual list of the ten "best" automobile engines available in the U.S. market, that are selected by Ward's AutoWorld magazine. The list was started in 1994, and has been drawn every year since then....
list for 2007 and 2008.
Uses
Daimler introduced BlueTec in the Mercedes E-ClassMercedes-Benz E-Class
The Mercedes-Benz E-Class is a range of executive-size cars manufactured by Mercedes-Benz in various engine and body configurations. The E initially stood for Einspritzmotor, ; a new feature in volume production vehicles at the time that the E-Class first appeared, with the E as a suffix to the...
(using the DeNOx system) and GL-Class
Mercedes-Benz GL-Class
The Mercedes-Benz GL-Class is a full-size crossover SUV built by the German carmaker Mercedes-Benz since 2006. The GL-Class debuted at the 2006 North American International Auto Show. The car was designed for the American market, which is shown by its large size, making it the only similarly sized...
(using SCR) at the 2006 North American International Auto Show
North American International Auto Show
The North American International Auto Show is an annual auto show held in Detroit, Michigan at Cobo Center, usually in January. It is among the largest auto shows in North America.-History:...
. At that time, these BlueTec vehicles were 45- and 50-state legal, respectively, in the United States (a 45-state vehicle does not meet the more stringent California emission standards that have also been adopted by four other states).
Daimler AG has entered into an agreement with Volkswagen
Volkswagen
Volkswagen is a German automobile manufacturer and is the original and biggest-selling marque of the Volkswagen Group, which now also owns the Audi, Bentley, Bugatti, Lamborghini, SEAT, and Škoda marques and the truck manufacturer Scania.Volkswagen means "people's car" in German, where it is...
and Audi
Audi
Audi AG is a German automobile manufacturer, from supermini to crossover SUVs in various body styles and price ranges that are marketed under the Audi brand , positioned as the premium brand within the Volkswagen Group....
to share BlueTec technology with them in order to increase the Diesel passenger-vehicle market in the United States. VW introduced the Jetta
Volkswagen Jetta
Although the Golf had reached considerable success, in the North American markets, Volkswagen observed that the hatchback body style lacked some of the appeal to those who preferred the traditional three-box configuration...
Clean TDI
Turbocharged Direct Injection
TDI or Turbocharged Direct Injection is a design of turbodiesel engines, which feature turbocharging and cylinder-direct fuel injection, developed and produced by Volkswagen Group. These TDI engines are widely used in all mainstream Volkswagen Group marques of passenger cars and light commercial...
, the Tiguan
Volkswagen Tiguan
Volkswagen Tiguan is a compact crossover vehicle initially built by the German automaker Auto 5000, but now built by Volkswagen, based on the PQ35 platform of the Volkswagen Golf. Production started in the winter of 2007 in Wolfsburg, Germany, and started selling shortly after...
concept, and the Touareg
Volkswagen Touareg
The Volkswagen Touareg is a mid-size crossover SUV produced by German automaker Volkswagen since 2002. The vehicle was named after the Tuareg people, a Berber-speaking group in North Africa...
BlueTDI as part of the BlueTec licensing program. The Jetta and the Tiguan use NOx adsorber
NOx adsorber
A NOx adsorber or NOx trap is a device that is used to reduce oxides of nitrogen emissions from a lean burn internal combustion engine.-Purpose and function of a NOx adsorber:...
s, while the Touareg uses a Selective Catalytic Reduction
Selective catalytic reduction
Selective catalytic reduction is a means of converting nitrogen oxides, also referred to as with the aid of a catalyst into diatomic nitrogen , , and water, . A gaseous reductant, typically anhydrous ammonia, aqueous ammonia or urea, is added to a stream of flue or exhaust gas and is absorbed...
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 competitor's branding for a product they would introduce into the market.
By 2010 a BlueTec version of the Mercedes Sprinter
Mercedes-Benz Sprinter
The Mercedes-Benz Sprinter is a light and heavy commercial vehicle, built by Daimler AG of Stuttgart, Germany as a van, chassis cab and minibus, and sold as a Mercedes model, except in the U.S. where it is built from complete knock down kits and was sold by Freightliner until 2010 when Mercedes...
was released. The BlueTec systems allowed the elimination of much of the EGR in that vehicle's engine, which as a result gives 188 HP compared to the non-BlueTec engine's 154 hp.
Rationale
The BlueTec system was created because the properties of the Diesel cycleDiesel cycle
The Diesel cycle is the thermodynamic cycle which approximates the pressure and volume of the combustion chamber of the Diesel engine, invented by Rudolph Diesel in 1897. It is assumed to have constant pressure during the first part of the "combustion" phase...
that give diesel engines high fuel efficiency also lead to relatively higher emissions of certain pollutants compared to Otto cycle
Otto cycle
An Otto cycle is an idealized thermodynamic cycle which describes the functioning of a typical reciprocating piston engine, the thermodynamic cycle most commonly found in automobile engines....
engines. High compression ratio
Compression ratio
The 'compression ratio' of an internal-combustion engine or external combustion engine is a value that represents the ratio of the volume of its combustion chamber from its largest capacity to its smallest capacity...
s and lean air-fuel mixtures make high combustion temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...
s, which results in more nitrogen oxides being released into the atmosphere
Earth's atmosphere
The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention , and reducing temperature extremes between day and night...
. While the particulate matter can be controlled with higher injection pressures and particulate filters, the big challenge is limiting NOx; Tier 2 regulations in the US are 0.05 grams per mile of NOx, which is ⅛ of the 0.40 limit in the European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...
.
Process
The whole exhaust system would work like so:- A Diesel oxidation catalystCatalytic converterA catalytic converter is a device used to convert toxic exhaust emissions from an internal combustion engine into non-toxic substances. Inside a catalytic converter, a catalyst stimulates a chemical reaction in which noxious byproducts of combustion are converted to less toxic substances by dint...
reduces the amounts of carbon monoxideCarbon monoxideCarbon monoxide , also called carbonous oxide, is a colorless, odorless, and tasteless gas that is slightly lighter than air. It is highly toxic to humans and animals in higher quantities, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal...
(CO) and hydrocarbonHydrocarbonIn organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons from which one hydrogen atom has been removed are functional groups, called hydrocarbyls....
s (HC) released from the exhaust. - A DeNOxNOx AdsorbersA NOx adsorber or NOx trap is a device that is used to reduce oxides of nitrogen emissions from a lean burn internal combustion engine.-Purpose and function of a NOx adsorber:...
catalytic converter begins a preliminary removal of oxides of nitrogen. - A particulate filterDiesel Particulate FilterA diesel particulate filter is a device designed to remove diesel particulate matter or soot from the exhaust gas of a diesel engine. Wall-flow diesel particulate filters usually remove 85% or more of the soot, and under certain conditions can attain soot removal efficiencies of close to 100%...
traps and stores soot particles, burning them off when the filter gets full. - If the above are not sufficient to meet the prevailing emissions regulations, a Selective Catalytic ReductionSelective catalytic reductionSelective catalytic reduction is a means of converting nitrogen oxides, also referred to as with the aid of a catalyst into diatomic nitrogen , , and water, . A gaseous reductant, typically anhydrous ammonia, aqueous ammonia or urea, is added to a stream of flue or exhaust gas and is absorbed...
(SCR) catalytic converter will take the remaining nitrogen oxides and convert them to nitrogen and water; diesel exhaust fluid is injected into the exhaust gas stream to enable the conversion.