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Seawater filtration as protection of ship RO system

Water desalination is the process of turning undrinkable seawater into fresh water by removing salt and other minerals.

In a large cruise vessel, with for example over 5,000 people on board including passengers and crew, 5 restaurants, 20 bars etc. the fresh water consumption is around 1,500,000 liters per day and seawater desalination clearly becomes a necessity. Fresh water can, of course, be tanked in port but, depending on ship size and travelling time, it also must be constantly produced on board to ensure independence and convenience.

How the filtration works

As water makers can only be used with cleaned sea water, the raw water is first passed through prefilters like the aquaBoll®, which eliminates suspended solids from the feed water. The water is then forced through reverse osmosis membranes, which remove salt and other minerals. While waste water or brine is released overboard, the fresh water is stocked in water tanks or is directly used.

BOLLFILTER as pre-filter and protection of the reverse osmosis system

RO-membranes are expensive and delicate. The aquaBoll®protects membranes by retaining algae and other microorganisms. Selfcleaning BOLLFILTERs can be adapted to reverse osmosis systems between 20 m³/hr and 1200 m³/hr.

Your benefits:

  • Footprint and weight reduction compared to media pre-filters
  • Precise filtration grade
  • Low maintenance and long lifetime as the filters are self cleaning
  • Easy waste management: Brine released over board. No need to dispose heavy media at the harbour
  • BOLLFILTER helps to protect the limited resource of drinking water
Preview Image: Case Marine
Case Marine »

The nominal capacity of the case Marine RO unit aboard the Grand Princess is 500m³/24 hr with a BOLLFILTER automatic pre-filter to protect the membranes by retaining algae and other microorganisms


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