

(Posted on 20/10/22)
The global maritime industry is making significant progress in the fight to reduce ship greenhouse gasses and other ship-to-air emissions, but it should not lose sight of what’s going on below the waterline, Thordon Bearings’ Craig Carter said, addressing members of the World Ocean Council (WOC).
Speaking in Barcelona on the first day of the WOC’s Sustainable Ocean Summit, Thordon’s Vice-President of Business Development said: “There are today a number of initiatives looking at reducing emissions above the waterline, but not so many looking at preventing pollution below the waterline. This can be part of global policies to improve our oceans and seas under the United Nations’ Sustainable Development Goals, Number 14 – Life Below Water.”
In answer to a question raised during the Sustainable Ports and Shipping for the Blue Economy session, Carter said: “To further advance ocean sustainable development and put to sea truly zero-emissions ships, then we really do have to get rid of the oil-lubricated shaft line and replace it with one lubricated by seawater. From well to wake, the environmental impact of an oil-lubricated sterntube needs serious consideration.”
According to numerous environment data sources, Carter estimated conservatively that leaks from the global shipping fleet’s propeller shafts resulted last year in more than 60 million gallons of oil polluting the world’s seas and oceans.
“This is about the same as the Amoco Cadiz spill, but it’s happening year after year after year, he said. “Oil-lubricated propeller shafts are often considered to be sealed systems, but they’re not. If they were, then a ship’s oil header tank containing 2000-3000 litres of oil wouldn’t need topping up with oil every few years!”
While damaged and worn sterntube seals contribute massively to the constant flow of oil into our seas and oceans, a research paper carried out last year by Linnaeus University’s Kalmar Maritime Academy concluded that sterntube seals are not at all leak free, with oil leakage considered “normal” operating conditions.
Carter went on to explain that the advancements made in elastomeric polymer materials over the last decade not only offer a viable environmental and economic alternative to the oil-based system but seawater-lubricated shaft lines can also figure in the shipping industry’s CO2 emissions abatement plans.
“Initial research suggests that because a seawater-lubricated propeller shaft system operates with lower friction coefficient (resistance) compared to one operating oil-lubricated white metal bearings, less fuel is required to propel the vessel, resulting in a small but nonetheless important reduction in carbon emissions.
“This means it can form part of a ship manager’s Carbon Intensity Indicator (CII) measures, which becomes mandatory next year under MARPOL Annex VI.”
The Sustainable Ports and Shipping for the Blue Economy discussion followed keynotes from Simon Bennett, General Manager, Sustainable Development, Swire Shipping Pte Ltd., and Jordi Vila Martinez Head of Environmental Department, Autoritat Portuària De Barcelona.
Other panellists were Pau Guasch, Co-Founder and General Manager, GPA SeaBots; Cristina Alexendri, COO, Bound4Blue; Ana Pinela, Senior Project Manager, Atlantic Smart Ports - Blue Acceleration Network; and Gina Panayiotou, ESG Manager, West of England. The session was moderated by Emma Cobos, Director, Innovation and Business Strategy, Port of Barcelona.
Magazzini Generali Silos Frigoriferi (MGSF), part of the Klingenberg Group, has ordered a Konecranes... Read more
FuelEU Maritime represents a strategic headache for shipping companies on the same level as its technical... Read more
Technology group Wärtsilä will upgrade the Wärtsilä RT-flex main engines... Read more
German coatings firm Steelpaint GmbH has secured a major order to supply its specialist Stelpant... Read more
In the wake of the International Maritime Organization's (IMO) Marine Environment Protection Committee... Read more
Global economic uncertainty and a cooling of the market has seen newbuild orders for dry-bulk vessels... Read more
Alfa Laval has completed the acquisition of UK-based NRG Marine, a leading provider of ultrasonic anti... Read more
In a landmark moment for the global maritime industry, the Maritime Battery Forum (MBF) and the Zero... Read more
Bruks Siwertell Group has announced a leadership transition as Peter Jonsson steps down as CEO after... Read more
ClassNK has issued an approval in principle (AiP) for a Rigid Windsail Type Wind-Assisted Propulsion... Read more