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What should you consider when choosing AdBlue®?

What should you consider when choosing AdBlue®?

Modern diesel engines are equipped with a selective catalytic reduction (SCR) system which requires the use of AdBlue®. Why is AdBlue® necessary and what you need to consider if you want to find the best one… You will find the answers to these and other questions in this article.

płyn AdBlue

AdBlue® as the rescue for diesel engines

The selective catalytic system has been the domain of heavy duty vehicles for years. With time, though, changing exhaust emission standards made passenger cars’ manufacturers more interested in this system as well. SCR has become one of the most frequently chosen methods used to achieve the required emission levels for vehicles. It has become the necessity for SCR car owners to regularly add AdBlue® to a special tank in their cars.

How does SCR system work?

How does the system with AdBlue® addition help to reduce harmful vehicle emissions? Nitrogen oxides (NOx) are one of the most environmentally harmful compounds produced in combustion processes in engines. The use of  AdBlue® triggers chemical reaction that transforms NOx particles into environmentally neutral nitrogen particles and water vapour.

How is this possible?

AdBlue® is a mixture of urea (32.5%) and demineralized water (67.5%). SCR system is responsible for injecting this fluid directly to the exhaust system. Exhaust fumes produced by a diesel engine go a long way and are cleaned at every stage. First, hydrocarbons unburned in the combustion process are oxidized in the catalytic converter. Then, particulate filter stops all unwanted particles. The next step is the injection of AdBlue® fluid which takes place just before the catalytic converter. The above-mentioned reaction occurs in the catalytic converter and results in harmful NOx being converted into environmentally neutral water (in gaseous state) and nitrogen.

The efficiency of SCR system in terms of nitrogen oxides reduction is estimated at 80%. The latest generation diesel engines which obtained Euro 6d-TEMP approval in 2018, achieved results significantly below the required NOx threshold during emission tests and emit on average 85% less NOx (nitrogen oxides) than cars meeting Euro 5 standard.

Fluid consumption

AdBlue® is dosed in small quantities by the selective catalytic reduction system so that it is not necessary to refill it too often – usually once every several thousand kilometres. It is estimated that the level of AdBlue® consumption translates into an average of 5% of fuel consumption value. Fortunately, an appropriate message on the dashboard reminds you to top up AdBlue® well in advance (usually more than 2,000 km before you run out of AdBlue®).

What happens, if despite warnings, we fail to add AdBlue® to the tank?

AdBlue® system may switch to emergency mode and if the engine is stopped you will not be able to restart it.

AdBlue®  filler cap is usually located next to the diesel filler cap. It is much smaller so that you do not accidentally add diesel to AdBlue® tank.

It is worth remembering that AdBlue® is not resistant to extreme temperature conditions. At temperatures below -5°C it may crystallize (it will return to its previous state when warmed up). Exposure to high temperature (above 25°C) accelerates its decomposition, shortening  its shelf-life at the same time. The best idea is to buy the fluid just when you need to refill.

AdBlue® and AdBlue are not necessarily equal – which product should you choose?

High purity AdBlue® is necessary for the proper operation of the system and, what goes with it, effective catalytic reduction. The use of low quality AdBlue® is responsible for most SCR system failure repairs. Contaminants it contains have a negative impact on the operation of the pump and interfere with electronics it uses (thanks to which the pump measures the right doses of the fluid). In extreme cases, the pump may seize or heaters integrated in the AdBlue® module may be damaged.

To keep the SCR system in  good condition we should always use AdBlue® from a renowned supplier. What distinguishes Kemetyl AdBlue®? First of all, the purity of its composition. If we choose this fluid we can be sure that its composition accurately reflects the appropriate proportions of water and urea and does not contain any harmful impurities. Additional advantage is its safe packaging with a dispenser allowing for precise application of AdBlue® to the tank without the risk of spilling.

Why is it so important?

As AdBlue® contains urea it has corrosive properties. If the fluid gets spilled on the car body, it may cause corrosion of some elements. This is exactly why it is not recommended to fill up with AdBlue® using dispensers at petrol stations intended for trucks. Because of the high pressure of fluid injection, it is then easy to spill it. Transporting AdBlue® in an unsecured tank, e.g. in the trunk of the vehicle, is also a bad idea. Its characteristic unpleasant smell is very hard to remove from upholstery, shoes or clothes. Clothes soiled with this fluid may no longer be usable.

We can easily avoid the above-mentioned problems if we use AdBlue® by Kemetyl with its dosing system equipped with a special funnel.

AdBlue® is a registered trademark of the Verband der Automobilindustrie, i.e. the German Association of the Automotive Industry.

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02-305 Warszawa

(+48) 22 822 5390