Ballast water treatment technology wins INTERTANKO’s Environmental Challenge

The winner of INTERTANKO’s Environmental Challenge will help the tanker industry take a major step towards complying with the ballast water requirements as adopted by the IMO in its International Convention on Harmful Aquatic Organisms in Ballast Water.

The problem? That ballast water management technologies have not been able to offer a solution that  treats or exchanges ballast water quickly, efficiently and without putting undue strain on a ship’s structure. The problem is sufficient to have prompted a caveat in the Convention to ensure that the IMO reviews whether adequate technology is available to meet the standards specified in the Convention.

A solution? The winner of the Environmental Challenge is NEI Treatment Systems with its Venturi Oxygen Stripping System. This system mixes very low-oxygen inert gas into ballast water as it moves through the ballast system, thereby removing 95% of the dissolved oxygen from the water in seconds. There is no flow limit. The result is that harmful aquatic organisms are suffocated within hours. A useful by-product of the system is that the deoxygenated ballast water and the inerted atmosphere in the ballast tanks provide increased protection against corrosion to the hull structure, with preliminary results from a 12-month corrosion test indicating up to 80% lower corrosion.

“Laboratory and pilot-scale biological testing indicate that this treatment results in the discharge of ballast water that will meet IMO standards,” says NEI’s President Peter McNulty, responding to industry concerns that technology might not be available to meet the deadlines set by the IMO. For further information NEI’s website is on and Peter McNulty can be contacted by e-mail on

Another solution to the same problem emerged through the Environmental Challenge, namely Teekay Shipping (Japan)’s Natural Ballast Water Exchange system which was one of the runners up. This system relies on natural flow and gravity forces to replace 95% of a ship’s ballast water, by taking clean water from an inlet in the vessel’s bow. It leads this clean water into the vessel’s ballast tanks through the main water ballast line, using positive pressure to push out tainted water through the sea chest by using the negative pressure/suction at the bottom of the hull of a moving ship. Ship’s power is only required at the final topping-up stage of the ballast exchange.

INTERTANKO’s Environmental Committee reviewed entries and made a shortlist for the distinguished panel of judges – Admiral Thomas H. Collins, Commandant of the US Coast Guard; Dr. Karl Laubstein, President of the WorldMaritimeUniversity; Dr. Claude Martin, Director General of the World Wide Fund for Nature (WWF); Mr. Efthimios Mitropoulos, Secretary General of the International Maritime Organization.

For fuller details on both runners up (Natural Ballast Water Exchange and VOCON procedure) and on the Environmental ChallengeClick here to view INTERTANKO’s press release on ‘Ballast water treatment technology wins INTERTANKO’s Environmental Challenge’ .

Contact: Tim Wilkins