Marine Installation Manual
2022-03
4-99
4 Ancillary Systems
4.9 Leakage collection system and washing devices
X62DF-S2.0
Figure 4
-
59 The iCER drainage system with two separate water treatment units for in
-
stallations with gas and diesel Tier III mode operation
Coagulant dosing
Depending on the design of the water treatment system, coagulant dosing may be
required. The water treatment system controls the coagulant dosing and removes
the particles accumulated by the coagulant as well as other hydrocarbons. The
coagulant is typically stored in small units and does not require any structural
tank.
NaOH dosing
Sodium hydroxide (NaOH), also known as caustic soda, is added to the EGC cir
-
culation water to neutralise the acidity. The alkali nature of NaOH counteracts
the acid build-up from washing of the exhaust gas.
The water acidity and quality are measured by sensors which are installed in the
EGC circulation water bypass stream. These sensors are connected to a control
unit, which controls the NaOH dosing pump and adds NaOH to the EGC circu
-
lation water.
SM-0850
o/w
EGC
NaOH
pH
QC
LT
LSH
1
2
3
Overboard
6a
1 EGC circulation water cooler
2 EGC circulation water pumps
(frequency controlled)
3 EGC circulation water tank
4 EGC drain tank
5 EGC sludge tank
6 Oil-in-water monitoring sensor:
6a UV type
6b Standard type
7 Bleed-off valves
8 Water analyser (pH and quality)
9 Level transmitter
10 High-level switch
EGC circulation water system
Bleed-off system
Water sampling line
Water treatment system
pH-neutralisation dosing unit
Venting pipes
with manual
override
7
o/w
6a
4
5
Fresh water
refill
8
Overboard
from SAC drain during
iCER operation
9
10
6b
o/w
Water
treatment
unit
o/w
Water
treatment
unit
6b
