Waste water treatment system for ships
A-WWTP
ISIR Impianti
Origin of the project
The existing international IMO regulations determine the limits of acceptability for the effluents of sanitary sewage treatment plants, but do not regulate the discharge to sea of grey waters (produced by showers, washbasins, galleys and laundries on board). Such discharge waters might in fact pollute the sea to a considerable extent, especially owing to their colouring, and therefore several Local Governments are imposing the "no discharge" rule also on them, with consequent difficulties for cruise liners and Pleasure Vessels, as well.
The adopted solutions
Ships sailing the seas of Alaska, the Caribbean, Greece, Turkey, etc. have long implemented modifications to their systems with a view to retaining on board this kind of waste (grey waters) and the effluent of sewage treatment systems when in territorial waters, and discharging them later in the high seas. The average fresh water consumption on board is of 300- 400 litres about per person per day and the Passenger Vessels cannot have specially dedicated holding tanks to allow several days stay in restricted areas, additionally, it is everywhere practically non-existent any facility to discharge to adequate shore sewerage connections. Because of this it has become of normal use to hold such very dirty water in the ship's ballast tanks, heavily polluting them and getting foul odours everywhere along the vessel.
