COVER STORY
22
PLANT / MACHINERY / VEHICLES AUGUST 2019 http://www.pmvmiddleeast.com
engine combustion and fuel management
such as variable valve timing, turbocharging,
stop-start systems, direct engine injection
technology and vehicle weight reduction to
reduce CO2 emissions, and exhaust aftewr-
treatment systems such as lean-NOx catalysts
and selective catalytic reduction (SCR)
converter systems to reduce NOx emissions.
Particle mass and particle number emissions
have been reduced by high-effi ciency diesel
particle fi lters.
Currently, the most popular method of
reducing NOx from the exhaust gases of diesel
vehicles is after-treatment with SCR converter
systems, which have been eff ective for almost
a decade.
Selective catalytic reduction is a chemical
reaction which converts NOx into water (H2O)
and nitrogen (N2) by using a reducing agent
such as urea (carbamide) and ammonia as the
reductant. The reducing agent, also called
diesel exhaust fl uid (DEF), is a 32.5% solution
of urea in deionised water. The DEF is not
a fuel or fuel additive; it’s a clear, non-toxic
liquid that is safe to handle and does not cause
damage to the environment.
The DEF is fi lled in a dedicated tank
installed beside the diesel tank. During the
SCR process, DEF is injected into the exhaust
gas stream, which converts urea into ammonia
initially and then reduces 80–90% of the NOx.
The ISO 22241-1:2019 standard specifi es the
DEF as AUS 32, and the German Association
of the Automotive Industry or Verband
der Automobilindustrie (VDA) markets it
worldwide as its registered trademark AdBlue.
After-treatment of NOx with SCR also
complies with the Euro VI emission standards,
which are being implemented globally. The
VDA estimates that 20 million vehicles from
German brands will be driving on Western
Europe’s roads by 2020 equipped with SCR
technology.
Diesel trucks imported in the UAE arerequired to comply with the Euro IV emission
standards. Because, the diesel quality in the
country is suitable for Euro V standards,
manufacturers are off ering Euro V models
instead of Euro IV.
The change in emission regulations has
boosted the supply of AdBlue in the UAE.
Trychem, a part of Germany-based Brenntag,
supplies DEF in 10-litre cans for fuel service
stations, 1,000-litre intermediate bulk
containers (IBCs) with pumps, and bulk
installations for both home depots and public
fi lling stations which are monitored with
telemetry solutions. Recently, the ENOC
Group launched its own brand of DEF called
ENOCBlue, which will soon be rolled out
across it retail network in the UAE. However,
there are barriers to the adoption of AdBlue,
such as its relatively high price and lack of
awareness among fl eet operators about
the necessity, application, availablity, and
regulations related to the product.