Bodymain Right

How the Cathelco BWT system works

During uptake the sea water passes through the filtration unit where the larger organisms and sediments are removed. At regular intervals material is automatically back-flushed and discharged at the original ballasting site.

The water is sampled by the UVT sensor system before reaching the UV chambers. The power to the lamps is automatically raised or lowered according to the quality of the seawater. This ensures the most effective treatment of the seawater whilst optimising power requirements.

As the water travels along the twin UV chambers in a ‘helix’, smaller organisms, bacteria and pathogens are rendered harmless before the water passes to the ballast tanks.

The lamps are continuously monitored by UV intensity sensors. These measure their performance and indicate when refurbishment or replacement is necessary.

During ballast discharge the seawater bypasses the filter unit and goes directly to the UV chambers where it is sterilised for a second time. This avoids the risk of any contamination due to re-growth in the ballast tanks.