The AdBlue urea is a registered trademark and is transferred as a license to the producing manufacturers. Only those companies that have successfully undergone various test and quality assurance procedures and meet the prescribed storage and logistics requirements may label their urea solutions with the AdBlue brand. AdBlue consists of 32.5% urea and 67.5% demineralized water. Demineralized water or deionized water, contains no salts as they occur in normal tap water.
Urea is produced from ammonia and carbon dioxide. The ammonia is produced from nitrogen and hydrogen. The AdBlue urea solution releases the ammonia again through the heat in the SCR cat and this converts the nitrogen oxides into harmless nitrogen, carbon dioxide and water vapour. The interaction of the modern SCR cat and the AdBlue urea solution makes it possible to reduce the nitrogen oxide content by up to 90%. Thanks to this exhaust gas purification and exhaust gas aftertreatment, EU exhaust gas standards can be complied with.
The AdBlue urea solution is considered harmless because it has the following properties:
Ammonia in itself is not harmful, but it can cause irritation if it gets into the eyes, respiratory tract and skin. The urea solution should therefore be rinsed off immediately with water if you have come into direct contact with AdBlue. In addition, the ammonia reacts corrosively with some materials. For example, it does not work well with car paint. Here, too, it is important to wipe AdBlue off immediately if something of the urea solution drips onto the paint.
According to the vehicle manufacturers, diesel drivers do not need to refill the AdBlue urea solution themselves, as one refill should last until the next maintenance interval. However, the average consumption of AdBlue is 5% of diesel consumption. Depending on the size of the AdBlue tank and the driving style, the urea solution may be used up earlier. A warning light in the cockpit will warn you when the urea solution is running low. Then you still have a range of approx. 2,000 kilometres. However, you should not exhaust these, but fill up the AdBlue as soon as possible. If you run out of AdBlue while driving, the engine switches to emergency driving mode and throttles the power. A renewed start of the engine without AdBlue is impossible, because the legislator has installed a so-called environmental immobiliser, because the exhaust cleaning is no longer active. Then at least 5l AdBlue are necessary before the engine starts again.
At most petrol stations there are AdBlue petrol pumps for trucks. However, these are not suitable for refuelling a diesel car. The reasons for this are as follows:
In the meantime there are already individual AdBlue petrol pumps for passenger cars. Otherwise one can fall back also simply to canisters, which give it in building markets, KFZ Shops or supermarkets to buy. Here at the best pay attention to the fact that the canisters have appropriate filler necks.
Since the AdBlue tanks are located differently, the canister size to be chosen is also different. The AdBlue tanks can be located at the following points in the vehicle:
In the manual of your vehicle you will find the exact location of the AdBlue tank. Smaller bottles / canisters up to 3.5 l are well suited for filling in the trunk and engine compartment. The 4.5l canisters are good for filling through the fuel filler flap. Anything larger should only be used for vans or trucks. The AdBlue urea solution can be filled as it is and should not be stretched or diluted with water. Especially not with normal tap water. The AdBlue must also not be decanted into a canister in which another liquid was previously in it, so that the urea solution is not contaminated and loses its effect.
As soon as the AdBlue tank has been filled, switch on the ignition and wait until the current filling level has been detected by the on-board computer and the warning message is displayed. Then the engine can be started as usual. Checking the fill level can take a few minutes on some vehicles.
It is very important when filling, never fill the AdBlue urea solution into the fuel tank and never fill the diesel into the AdBlue tank. The latter happens very rarely because the filler neck of the diesel does not fit into the AdBlue tank opening, but the other way around it can happen again and again. Once the mishap has happened, the engine should never be started. Then only the tank would be affected, could be cleaned intensively and refilled with diesel. Effort and costs were kept within limits. If, however, the engine is started, the AdBlue does not get into the SCR catalytic converter for exhaust gas cleaning, but into the engine and attacks seals, pipes, etc. The AdBlue is then cleaned by the SCR catalytic converter. Here the damage will be greater and thus also cause higher costs, as the fuel pump, pipes, injection system and filter, among other things, have to be replaced.
As the SCR catalytic converter is precisely matched to the composition of AdBlue, it is strongly discouraged to use other substitutes for exhaust aftertreatment. These may cause damage to the catalytic converter or control unit and generally void the warranty. The AdBlue is also not very expensive. The average price for AdBlue urea solutions is between €1.00 and €3.50 per litre (as of September 2019). With us you receive them already starting from 0,90€ the litre.
As the AdBlue urea solution consists of approx. two thirds water, the freezing point of the liquid is -11°C. For this reason, the AdBlue tanks are heated, as are the pipes to the exhaust pipe. In very cold areas it makes sense to put the car in a garage if possible. If the heating of the AdBlue tank breaks down, a warning message will appear and the car should then be brought to the workshop as soon as possible, as the exhaust gas cleaning does not function sufficiently in winter.
The AdBlue does not like higher temperatures very much either, since the urea content decreases when exposed to temperatures above 30°C for longer. The reason for this is ammonia, which evaporates at high temperatures. It is therefore not recommended to carry AdBlue canisters with you in your car. It is best to store them in a cool and dry place.
In summary, with the SCR cat and the AdBlue urea solution it is possible to achieve great effects in exhaust gas purification and to comply with EU exhaust gas standards. Be sure to use the original AdBlue labelled urea solution. Only with this can your vehicle achieve the highest possible performance with the lowest environmental impact. We wish you a pleasant journey at all times.