Man L23/30DF, Руководство по проекту

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Engine supply systems
SCR system
The SCR system uses aqueous urea solution and a
catalyst material to transform the pollutant nitrogen
oxides into harmless nitrogen and water vapor. The
main components of the SCR system are described
in the following section.
For further information read section "SCR - Special
notes".
All components will be delivered and packaged in a
seaworthy way (with dry agent, wooden boxing,
shrink wrapped). Black carbon steel components
will be coated with an anti-corrosive painting. Stain-
less steel components will not be coated.
The original packaging should not be removed until
the date of installation.
The physical integrity of the packaging must be
checked at the date of delivery.
Compressed air reservoir module
(MOD-085)
Transport of the compressed air reservoir module
can be organised by crane, via installed metal eye-
lets on the top side or fork
‐
lifter.
Urea pump module (MOD
‐
084)
Transport of the urea pump module can be organ-
ised by crane, via installed metal eyelets on the top
side.
Dosing unit (MOD
‐
082)
Transport of the dosing unit can be organised by
crane, via installed metal eyelets on the top side.
Urea injection lance and mixing unit
(MOD
‐
087)
Transport of the mixing unit can be organised by
crane, via two installed metal eyelets. For horizontal
lifting it is sufficient using one of the metal eyelets.
Using a vertical way, the two cables each fixed on
one metal eyelet have to be stabilised by a transver-
sal bar.
The metal eyelets are designed to carry only the
segments of the mixing unit, further weights are
not allowed (e.g. complete welded mixing pipe).
SCR reactor (R
‐
001)
Transport of the reactor can be organised by crane,
via installed metal eyelets on the top side.
SCR control unit
Transport of the reactor can be organised by crane,
via installed metal eyelets on the top side.
Compressed air reservoir module (MOD
‐
085), urea
pump module (MOD
‐
084), dosing unit (MOD
‐
082),
SCR control unit and sensor elements have to be
stored in dry and weather
‐
resistant conditions.
Catalyst elements shall be handled free from shocks
and vibrations. Furthermore, catalyst elements have
to be stored in dry and weather
‐
resistant condi-
tions. Keep oils or chemicals away from catalyst
elements. Seaworthy packaging is only a temporary
protection.
Catalyst elements
The catalyst elements are placed in metallic frames,
so called modules. Due to the honeycomb structure
of the catalyst elements, the catalytic surface is
increased. The active component Vanadium pent-
oxide (V2O5) in the surface supports the reduction
of NOx to harmless nitrogen.
The effectivity of the catalytic material decreases
over time because of poisoning via fuel oil compo-
nents or thermal impact. The durability depends on
the fuel type and conditions of operation.
The status of catalyst deactivation is monitored
continuously and the amount of urea injected is
adapted according to the current status of the cata-
lyst.
MAN Diesel & Turbo
B1600 0
SCR (Selective Catalytic Reduction)
3700467-8.1
Page 12 (17)
V28/32S, L28/32S, L28/32H, L27/38S, L27/38, L23/30S, L23/30H, L21/31S,
L21/31, L16/24S, L16/24