New warning on bauxite from IMO


A new warning that bauxite may become unstable when carried in bulk on a ship, potentially causing the vessel to capsize, has been issued by the International Maritime Organization (IMO). Bauxite is one of the world’s major sources of aluminium with around 100 million tonnes transported annually by sea. In 2015 a bulk carrier sank while transporting bauxite, with the loss of 18 seafarers. Research presented recently to an IMO sub-committee found that certain forms of bauxite with a large proportion of smaller particles could be subject to a newly-identified phenomenon of “dynamic separation” when there is excess moisture in the cargo. In such conditions, a liquid slurry (water and fine solids) can form above the solid material, according to the report of an international global bauxite working group on research into the behaviour of bauxite during shipping. The resulting free surface effect of liquid sloshing about could significantly affect the vessel’s stability, leading to the risk of the ship capsizing.