IMPORTANT FAQS RELATED TO DEF
Using DEF is not always straightforward. Here are a few answers to commonly asked
questions about it
1.What is DEF?
Diesel exhaust fluid (DEF) is a non-hazardous solution comprised of technical grade urea
and pure deionized water. It is a critical component of Selective Catalytic Reduction (SCR)
technology, which has been widely accepted as the most effective means to reduce
concentrations of Nitrogen Oxides (NOx) and meet emission requirements by reducing the
amount of air pollution created by a diesel engine.
It is neither a fuel nor a fuel additive and is added to a separate tank in the vehicle. There is
a certain level of DEF that needs to be maintained in the tank otherwise the vehicle's
performance may be affected adversely and this may lead to a breakdown.
2. Is DEF the Same as AdBlue?
AdBlue is simply a brand name of DEF registered in Germany. It has become a very popular
and widely recognized product that many people use interchangeably with DEF. Despite the
name, AdBlue is not actually blue and is colorless
3. What Happens When You Run out of DEF?
If you were to run out of DEF, most systems would not allow you to start the engine. Take
diesel trucks, for instance. If they run out of DEF, the trucks won't start until the fluid is
refilled. While that might sound concerning, as though it could leave you on the side of the
road, all modern diesel vehicles will give you ample warning before the DEF runs out.
Another possibility is that the vehicle will limit your speed. Once DEF is added, it will offer
normal speeds again.
4. Can You Substitute Water in for DEF?
No, you cannot put water in the DEF reservoir. The system will identify it as poor quality DEF
and will not start up. Even if it did, water does not contain the ingredients needed to convert
harmful gases to non-harmful ones. You would be doing a lot of harm to the environment
and any efforts toward compliance. .
APPLICATION
SFPL DEF is recommended for modern Commercial Vehicles (Trucks & Buses), Diesel SUVs
and any other BS IV / VI or (Euro IV/V/VI) compliant diesel engines employing SCR /
EGR-SCR technology for NOx
5. Can a Diesel Engine Run Without DEF?
No, diesel engines won't run without DEF. If you have completely run out, it simply will not
start.
6. How DEF increases fuel mileage and benefit's fleet operators?
The major advantage of DEF is that; it maximizes vehicle's fuel efficiency. DEF has high
oxygen levels that allow your vehicle to not only have cleaner nitrogen and water emissions,
but the combustion itself is more efficient, consequently using lesser fuel. The SCR system
coupled with DEF performs efficiently to give out cleaner emissions. In fact, various reports
suggest that using DEF can increase fuel mileage by up to 5%.
Because of the use of SCR and DEF, it has been found that engine improvements actually
made it possible to get more power from the engine. Therefore, the addition of DEF to your
fleet will not only give you extra power but will also add mileage to your fleet operations.
As a fleet operator today, with the use of DEF you can be assured of the increased life
expectancy of your vehicles. Now, since the engines run extra efficiently so that you can stop
worrying about any wear and tear on the engine components which is likely and expectedly
to reduce the chance of frequent repairs and maintenance. This will in turn reduce your
overall fleet maintenance costs and will help you manage your fleet with more control
effectively. Therefore, the efficiency of an SCR engine that uses DEF allows you to worry less
about engine maintenance now and in the future.
7. What Is Selective Catalytic Reduction?
Another common acronym you will find surrounding DEF is SCR, or selective catalytic
reduction. This emissions control technology is what uses DEF and allows it to interact with
the engine's exhaust. It injects the DEF through a catalyst and into the exhaust stream, where
the DEF starts a chemical reaction, turning the nitrogen oxide into nitrogen, water, and some
carbon dioxide. Then, it gets sent out through the tailpipe and into the air, where it is safe to
breathe in and does not harm our environment the way nitrogen oxide would.
Nitrogen Oxide emissions are poisonous gases that contribute heavily towards
environmental pollution and are often blamed for acid rains and greenhouse gas effects.
Therefore, by using DEF you are not only complying with environmental regulations but also
doing your bit to protect the environment. Because DEF breaks down Nitrogen Oxide gases
into nitrogen and water, which are harmless on their own.
Back in 2010, the Environment Protection Agency (EPA) mandated the use of Selective
Catalytic Reduction (SCR) in all diesel vehicles. However, SCR is not a new invention, in fact
it has been around for nearly half a century. In India with the advent of Bharat Stage VI (BSVI)
norms, diesel engines will have to reduce their HC + NOx (hydro carbon + nitrogen oxides)
by 43%, their NOx levels by 68% and particulate matter levels by 82%. This is where the role
of Diesel Exhaust Fluid (DEF) comes into play as DEF is going to work as a catalyst with
Selective Catalytic Reduction (SCR) towards improving the overall health of the environment
and making diesel vehicle a responsible choice and a more viable option for the future.
