AdBlue, to limit the pollution of diesel vehicles

The new anti-pollution standards are more and more demanding. They have pushed car manufacturers to look at the problem of reducing pollution and the need to take action to preserve our environment. It is from this ecological emergency that AdBlue was born. But what is it really about? Is this a really spectacular product? And are there disadvantages to its use? We guide you to a better understanding of this product.

What is AdBlue?

THE'AdBlue is an additive developed for meet the specific needs of the diesel engine, while limiting the pollutant impact of this fuel. A tank for receiving this liquid is installed on the new vehicles put on the market and which are subject to the Euro 6 standard in application since 1er September 2014.

These vehicles are specially equipped with a selective catalytic reduction system (CBC). This device is indicated to reduce emissions of carbon monoxide (CO), unburned hydrocarbons (HC), fine particles (PM) but also nitrogen oxides (NOx). The SRC has already been present since 2005 on trucks and tends to prevail on new vehicles coming out of the factory. It is developed to reduce our impact on the environment and to cope with the inconvenience produced by the diesel engine.

How does AdBlue work?

AbBlue BP Pump

This additive solution is used in the SCR to transform nitrogen oxides into nitrogen and water vapor that are naturally present in the air that we breathe. The action of AdBlue converts a harmful polluting gas into two elements that are not dangerous for nature and our health.

This solution, composed of demineralised water (67,5%) and urea (32,5%), does not present any risk of explosion or risk of igniting. It is not aggressive to the environment, but can become corrosive when it comes into contact with certain metals. AdBlue guarantees the standards in accordance with ISO 22241 and DIN 70070 quality. Using other additives would be risky for the durability and operation of your vehicle.

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When AdBlue is injected into the catalyst, it enters into a chemical reaction with the exhaust gas and attenuates the presence of the polluting components. Ammonia molecules that are present in urea are released to oxidize Nox produced by a diesel engine. The transformation is evolving towards the production of dyazote and water vapor, which are then released into the ambient air. The action occurs as soon as the temperature of 190 ° C is reached.

Which vehicles use AdBlue?

Only vehicles with an SCR system can use the AdBlue additive. The latter is already present on part of the truck fleet. It is installed on many other vehicles such as utility trucks, motorhomes or minivans and 4 × 4 vehicles. For some time, many vehicles have been originally equipped with an SCR which is composed of a catalyst, a specific reservoir for AdBlue, an additive injection unit and a control to properly dose AdBlue. The product is also reserved exclusively for engines powered by diesel.

How should you use the Adblue additive?

This additive product should not be mixed with fuel as many other additives. Vehicles with an SCR must have a tank adapted to accommodate the AdBlue. So add the additive in this tank, which is closed by a blue cap easily recognizable. When the tank is empty, a warning light will come on your dashboard to warn you that AdBlue must be delivered. The tank is located at different locations depending on the model of the vehicle. Thus, it can be located in the same place as the hatch of the fuel tank, but also under the hood of the car or in the trunk. You should know that a vehicle with SCR will not work if you do not add AdBlue.

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What precautions should be taken ?

The product is not harmful to the environment, but it can be corrosive when it comes into contact with certain materials such as metal. Avoid spilling when refueling your tank. Clean your hands after use.

Regarding the conservation of cans, you have to be very careful. AdBlue does not support UV rays and risk losing quality if it undergoes type of contact. It must therefore be stored in a place protected from light. It also does not like extreme temperatures (frost and heat), the ideal temperature for storing it is between 0 and 30 ° C.

In addition, it does not withstand storage that exceeds 18 months. So quickly use the doses you have and buy the containers according to your needs. You will find ibc 1000 liters in bulk, cans of 210 liters or 10 liters. Choose the solution that best suits your AdBlue consumption.

Advantages and disadvantages of AdBlue

This product has many advantages, but also some disadvantages that must be taken into consideration.


  • AdBlue is engineered to make diesel engines cleaner and reduce our impact on the environment.
  • SCR technology is known to be very effective at acting on nitrogen oxides and NOx that have been scandalous lately in some automakers.
  • Most future cars will be equipped with this system to ensure compliance with European standards.


  • Even if the product is not so expensive, it still represents an additional cost in the long run. It is therefore advisable to buy containers in large quantities to reduce costs. The purchase of small containers at a service station or at the builder's premises can quickly become a financial pitfall.
  • The SCR tanks of equipped vehicles are still too small to completely eliminate the pollution related to the exhaust gas.
  • When the AdBlue tank is empty, your vehicle loses power and may also refuse to start.
  • The consumption of AdBlue also depends on your driving style and the type of vehicle used.
  • If the warning light comes on, there is a small reserve of AdBlue but it should not be delayed to refuel, so as not to alter the operation of the vehicle.

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3 comments on "AdBlue, to limit the pollution of diesel vehicles"

  1. All this is inaccurate because diesel kills. The ICCT report (International Council
    on Clean Transportation) of February 2019 demonstrates that two-thirds of
    excess mortality caused by air pollution in France are linked to
    diesel engines.
    And this concerns the latest models as well as the older ones. This explains
    for two main reasons, that the defenders of diesel often feign
    forget. The first reason is the chemical nature of the particles from
    diesel engines - different from those of gasoline engines. It's for this
    because the International Agency for Research on Cancer ranked them
    as "certain carcinogens" in 2012. All the talk about the amount of
    particles is only meant to make us forget the health problem
    major related to the chemical composition of particles.
    The second reason is that diesel engines emit a lot of
    nitrogen dioxide (NO2), a gas that is toxic to the respiratory system and
    cardiovascular. Five to six times more than a gasoline vehicle! Levels of
    NO2 exceed the legal limits in most major
    French agglomerations - because of diesel engines.
    The Court of Justice of the European Union is specifically suing France for
    these reasons. The diesel industry replies that new
    decontamination, such as selective catalytic reduction (SCR) with additive-type
    Ad Blue, solve the problem. Unfortunately, that's wrong, and
    we never stopped to recall our doubts about the engines
    diesel. Indeed, driving with cold start and over short distances, in
    city, does not allow to reach the temperature necessary for the good
    operation of these pollution control systems, which leads to significant
    releases of nitrogen dioxide. Worse, by not working properly, the
    Ad Blue systems release NH3 and NO2 that can - by combining -
    form secondary fine particles!
    This malfunction also leads to the production of protoxide
    nitrogen (N2O), a greenhouse gas 300 times more powerful than CO2. Of
    same, the catalysts limiting the emissions of aromatic hydrocarbons
    polycyclic agents (PAHs), extremely toxic and carcinogenic agents,
    operate little in town and at startup when the engine is cold.
    As for particle filters, they require regular maintenance that does not
    subject of any regulation. Finally, they let nanoparticles escape
    even more toxic and which, because of their size, will be able to penetrate the system
    cerebral and especially the placenta, as has recently been
    demonstrated on diesels equipped with particulate filters.
    Tests performed on diesel vehicles covered by the Euro 6d-Temp standard
    show that in conditions more representative of the actual conduct of
    users, N2O and fine particle emissions soar, up to
    nine times the allowed limits. Proof of its insufficiency, the standard Euro 6d-
    Temp needs to be revised in 2019 following the complaint from the cities of Paris, Brussels and

    1. Adblue precisely limits NOx emissions so this is not wrong, deaths are avoided thanks to the Adblue!

      The Adblue does not intervene, on the other hand, on the particles (fine or less fine): this is the role of the particulate filter which is almost standard on all recent diesel (before it could be proposed ... optional! A height!)

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