Ballast water treatment method and ballast water treatment system in a ship including at least two ballast tanks

摘要

Ballast water in a ship is treated in at least two ballast tanks with a system for treatment of ballast water. The ballast tanks are in fluid communication with each other so that ballast water can be pumped to each one of the ballast tanks and so that ballast water can be pumped between the ballast tanks either treated or untreated. Ballast water is pumped onboard such that at least one ballast tank is left empty. Next, ballast water is pumped via the system for treatment of ballast water from one ballast tank with untreated ballast water to an empty ballast tank. Pumping and treatment continue until the ballast tank being pumped from is empty.