Frequently asked questions / AdBlue

Has SCR-technology been chosen by all heavy-duty vehicle manufacturers?

- For Euro 4: no, not all manufacturers opted for SCR technology. MAN chose the EGR (Exhaust Gas Recirculation) technique and Scania decided in favour of the EGR technique for most of its models as well. All other manufacturers have chosen for SCR technology at the stage of Euro 4.

- For Euro 5: yes, all manufacturers - including MAN and Scania - have decided to implement the SCR technique, which requires the use of AdBlue.

What are the advantages of the SCR technology?

- Reliability: the SCR technique has proven to be absolutely reliable during extensive testing in the last few years.

- Solution for the longer term: with SCR technology Euro 4 and Euro 5 standards can easily be met. New, still to be developed emission standards will also require this technology.

- Less fuel consumption: due to the possibility of tuning the diesel engines in a more economical way, an average fuel saving of 5 % can be realised.

- Tax reductions and subsidies: several European countries encourage compliance with Euro 4 and 5 standards by offering financial incentives. For instance, in Germany lowered road tolls result in a financial advantage of €0,02-€0,03 per kilometre.

What are the disadvantages of SCR technology?

- You are obliged to use AdBlue.

- The new vehicles are more expensive. But so are vehicles equipped with other techniques in order to comply with emission standards.

Has this technology been field-tested?

Millions of kilometres have already been driven in order to test the new technology. It has also been tested under extreme weather conditions, in Spain and Finland.

What makes AdBlue so special?

AdBlue is an extremely pure solution. It is not simply an aqueous urea solution but a product manufactured in strict compliance with the technology and under stringent requirements, using water with purity grade higher than that in medical applications. For the production of AdBlue, Prista Oil applies the method of double reverse osmosis for water purification. Heavy-duty vehicle manufacturers demand this level of purity of AdBlue, because of the warranty they give on their vehicles.

Since the opening of the nozzle injecting the product is very small, even the smallest presence of metals in the product results in nozzle clogging.

What is the storage life of AdBlue?

The maximum storage period is 1 year, under the condition of storage specified by the manufacturer. Temperature is a very important factor in this, as well as sealed packaging and a dry and well-ventilated storage space. The product should not be exposed to direct sunlight!

What happens if a heavy duty engine runs without AdBlue?

This will result in crossing the allowed emission levels. Diesel engine runs in a fuel optimized way, which has a negative impact on the NOx emission. For that reason sensors are placed in the exhaust pipe to measure the NOx emission precisely. The measurement results are stored in the OBD-system (On Board Diagnostic – the board computer).

Is AdBlue available at public petrol stations?

Owing to the excellent partnership relations between Prista Oil Holding EAD and Petrol AD, AdBlue is available at most of the “Petrol” filling stations in Bulgaria, in 10L and 18L packages.

Soon, automatic systems for AdBlue filling will be operational at the major petrol stations in the country.