by Ivan K. Makoku, Director(AirNox Pty Ltd) | September 22, 2023

The research, development, and introduction of environmentally friendly SCR technology using diesel exhaust fluid (AdBlue®)

Besides European countries and Canada with their own set of constraints and limitations on Nitrogen Oxide (NOx) emission from medium and heavy vehicles, United States Environmental Protection Agency (EPA) also established the same solutions for their medium and heavy-duty vehicles. So, to achieve this, engine manufacturers started their research and investigation on various technologies to reduce the emission. Eventually SCR (Selective Catalytic Reduction) became a proven method and a  SCR technology to satisfy the environmental needs. Hence, introducing AdBlue® in USA.


What is SCR technology and how does it work for vehicles like trucks, buses and other automobiles?

The term “SCR” is an abbreviation for Selective Catalytic Reduction and refers to a technology that involves post-combustion treatment of the exhaust system from diesel automobiles that allows them to minimise dangerous NOx (Nitrogen Oxide) emissions. This method creates a necessity to use a reagent known as AdBlue® or Diesel Exhaust Fluid. Almost all the major engine manufacturers employ this technology to fulfil the needs of new NOx (Nitrogen Oxides) emission law.

The following are the primary components of the SCR system:

  • Catalyst for SCR
  • AdBlue® refill unit
  • AdBlue® storage tanks
  • Control unit for AdBlue® injection.

You can buy AdBlue® pump kit to refill your truck/bus yourself from stored AdBlue® in 210L drum or 1000L IBC. This storage facility makes you purchase AdBlue® in bulk which helps you get it at a discounted price.


Maintenance of your vehicle’s SCR system for the good performance of your vehicle

The SCR system is a pre-installed system on your vehicle provided by the manufacturer and operates automatically. It does not require special maintenance or any alterations. AdBlue® is automatically injected into the exhaust system depending on the vehicle engine size. Consumption of AdBlue® depends on the quality of the solution and it is adjusted accordingly by the manufacturer.

It is advisable to use high quality AdBlue® from AirNox with high grade to ensure proper function and longevity of the SCR system. Using low quality solution may lead to performance degradation of the engine as the impurity in the solution creates a negative impact on the SCR system and injectors.

Replacing and refilling AdBlue® in your vehicle?

There is no restriction on how frequently AdBlue® must be refilled. However, it is a good idea to get it refilled every six months, in addition to your routine car service for passenger vehicles. If your car runs out of AdBlue®, a warning light will appear on the dashboard. Continuing driving your vehicle even after the warning may cause serious damage to your car leading to a sudden shut down of the engine.

Like the diesel storage tank, the AdBlue® storage tank is big enough to store AdBlue® that can run for a while before a scheduled servicing/refilling. Your vehicle will automatically use AdBlue® at the required amount, depending on your driving practice. AdBlue® usage is typically between 4% to 8% of diesel used for commercial vehicles. For every 100 litres of diesel used, you will need four (4) to eight (8) litres of AdBlue®.

On the other hand, the average use of AdBlue® for passenger cars is 1.5 litres for every 1000km. The AdBlue® warning light will come on when you have about three (3) litres left which should be enough to drive for approximately 2000km.

The 2000km driving range should be enough for an average customer to order AdBlue® online at: or For international customers interested in buying AdBlue® in bulk do not hesitate to contact


Summarizing the details on AdBlue®

AdBlue® is a non-toxic fluid that is used in diesel automobiles to combat air pollution. It is a liquid that converts harmful particles into clean air.

AdBlue® is a clear solution comprised of high-purity urea and de-ionized water. Urea is a key component of AdBlue® because it includes ammonia, which decreases NOx (Nitric Oxide and Nitrogen Dioxide) emissions before they enter the environment.

Euro 6 compliant diesel vehicle must not emit more than 80gm/km of NOx. Hence, to meet this requirement automobiles utilise SCR technology, which uses AdBlue® to minimise NOx emissions. Therefore, it is becoming a very basic requirement for our daily lives. AirNox help desk is always available to help our customers across South Africa, Africa, and the global community.