Alfa Laval PureBallast 135 Compact USCG, System Manual

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If the system malfunction in connection with general cargo operation, ballast
and deballast operations should be avoided.
The procedures concerning emergency and malfunction of the ballast water
treatment system should be implemented in the ships Ballast water
management plan.
2.3 System components description
This section gives an introduction to the most important PureBallast system
components and their functions in the system.
2.3.1 UV reactor
The main part of PureBallast is the UV reactor.
2.3.1.1 UV reactor working principle
The main treatment process take place inside the UV reactor, where the
micoro organisms in the water is exposed to UV light, which renders them
completely harmless.
The UV light breaks the DNA chain resulting in an internal connection (T+T)
making it impossible for the micro organisms to reproduce.
Destruction of DNA
There are no chemical substances added to the process, and there are no
toxic residuals created. Since the water is not affected chemically, there are no
environmental impact and the process does not influence corrosion in any
way.
2.3.1.2 UV reactor description
The UV reactor consist of the reactor, sensors and valves for water and CIP
liquid, as shown in the illustration below. The UV reactor accommodates 6
medium-pressure UV lamps (3 kW each).
The UV lamps are enclosed in individual quartz-glass sleeves.
The UV lamps get very warm, so they must be cooled whenever they are lit.
To secure that there is water in the reactor when the lamps are lit, the reactor
is equipped with a level switch. The level switch also secures that enough CIP
liquid is pumped into the reactor during the CIP process. To secure that the
lamps are adequately cooled by the ballast water,
the UV reactor has a threefold heat protection:
200000695-1-EN-GB 26
2 System description EN