the IHS Ballast Water Guide - RWO Marine Water Technology

IHS Fairplay Solutions Guide to Ballast Water Treatment Systems Sponsored by
substances during ballasting and deballasting.
The system combines filter and UV units,
employs backflushing and is cleaned by
automatic wiping. The filter unit maximises
the disinfection effect of the UV unit by
improving transmittance of UV light. The
filter not only eliminates organisms larger
than 50µm, but also minimises sediment in
the ballast tanks.
Water enters through the inlet pipe
into the filter area and flows through the
cylindrical filter element from inside out.
The filtration cake accumulating on the
element surface causes a pressure differential
to develop across the filter element. When
this pressure difference reaches a pre-set
value, or after a pre-determined time lapse,
the backflushing mechanism kicks in.
Backflushing takes 10–30 seconds. During
the backflushing cycle the filtered water
is not interrupted and continues to flow
downstream of the filter.
Contaminated water is exposed to UV
light. A real-time process control system
activates and deactivates lamps to maintain
the UV dosage while conserving power. This
is controlled and monitored by means of a
programmable logic controller (PLC) and
touchscreen.
Sky-System
Peraclean Ocean
The Sky-System ballast water management
system consists of treatment with the
Peraclean Ocean preparation, which contains
the active substances peracetic acid and
hydrogen peroxide, which are stored in
double-walled tanks.
The concentrations of the active substances
are monitored and, if necessary, neutralised
with sodium sulphite (Na 2 SO 3 ) and water
before the ballast water is discharged. The
5
neutraliser is contained in epoxy-coated tanks.
Temperature and leakage sensors,
temperature control unit, ventilators and
sprinklers in the chemical storage room
are used to prevent the temperature from
exceeding 35ºC.
During land-based tests using the
concentration of active substance that is
applied in actual operation, no corrosion was
observed. Corrosive influences were reported
to be acceptable on the ballast tank coatings ng
and uncoated materials.
OceanGuard
Qingdao Headway
2 9
OceanGuard has been developed by Headway
Technology from Qingdao, together with the
Engineering department of Harbin University
in China.
An Advanced Electrocatalysis Oxidation
Process (AEOP) is used to manage the
treatment, in which short-lived hydroxyl
radicals are produced. Because of their highly
reactive efficiency in chained mode and effect
of the oxidative breakdown, the radicals
perform broad spectrum sterilisation, killing
off the various forms of bacteria, virus, algae
and dormant ovum in the ballast water. The
organisms are transformed to simpler organic
molecules that are eventually mineralised to
CO 2, H 2O and trace inorganic salt.
OceanGuard has three main components.
The control unit contains the procedures for
system operation. It has system diagrams and
sensor displays and is used for monitoring and
regulating data readings and dealing with any
alarm signals.
A fully automatic 50µm backflush filter,
which can accomplish automatic backflush
and filtering at the same time, prevents large
organisms from entering the ballast tank to
reduce sedimentation.
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