DETOXIFICATION TREATMENT METHOD FOR SEAWATER STORED IN BALLAST WATER TANK OF SHIP, AND APPARATUS THEREFOR

PROBLEM TO BE SOLVED: To suppress hull remodeling cost as much as possible for installing a detoxification treatment apparatus for even an existing ship by reducing an installation space of the detoxification treatment apparatus for the ballast water in a ship for increasing a loading space for cargoes and the like, in removing microorganism in ballast water comprised of untreated seawater for conversion into clean and harmless ballast water.SOLUTION: In a detoxification treatment method which removes microorganisms in untreated seawater for its conversion into clean treated sea water, either one of chlorine treatment and oxidation material addition treatment is implemented. The chlorine treatment kills or sterilizes the microorganisms by creating chlorine-containing material from the seawater and injecting the created material into the seawater. The oxidation material addition treatment adds a substance with oxygen behavior to the seawater. Either one or both of treatment by activated carbon and treatment by a metal catalyst are implemented for the treated seawater after the chlorine treatment or oxidation material addition treatment, and the treated seawater is stored in a ballast tank.