- Cargoes subject to potential liquefaction issues are referred to as Group A cargoes in the International Maritime Solid Bulk Cargoes (IMSBC) Code.
- The IMSBC Code contains an individual schedule for BAUXITE, which is a Group C cargo defined as liable to neither liquefy (Group A), nor to possess chemical hazards (Group B).
- IMO's Sub-Committee on Carriage of Cargoes and Containers (CCC); through circular CCC.1/Circ.2/Rev.1, warns of the dangers of Bauxite cargo; noting that some bauxite cargoes, specifically those which contain more amount of bauxite fine particles, present a risk caused by moisture and may be treated as Group A cargoes.
- Dynamic separation occurs during a voyage when the cargo contains enough small particles that stop the moisture draining from the cargo.
- Bauxite fines cargo may be subject to Dynamic Separation due to moisture content, forming liquid slurry above the solid material creating a free surface effect which may affect the ship’s stability while transporting this cargo.
- Based on above, the IMO circular includes following draft amendments which are pending for adoption in 2019 and expected enter into force to the IMSBC code on 1 January 2021:
- Draft Test Procedure for Determining the transportable moisture limit (TML) for bauxite;
- Draft individual schedule for bauxite of Group A (Bulk Cargo shipping name as "BAUXITE FINES"); and
- Draft amendments to the existing individual schedule for bauxite of Group C (bauxite with a lower amount of fine particles and the degree of saturation due to moisture is not liable to reach 70%).
- In view of above, Republic of Liberia has revised Marine Advisory no.02/2018 providing guidance for safe transport of bauxite and potential risks associated with carriage of such cargoes.
- Administration has provided below link to AMSA website where the above dynamic separation phenomenon in bauxite cargo is described showing the effect of free slurry on stability of ship.
- Administration has advised owners, operators and masters to take appropriate actions and act accordingly taking into account the provisions of relevant requirements while handling and carrying bauxite in bulk.
- Also masters are encouraged to carefully follow the requirements of IMSBC code section 7 and 8 regarding additional information on cargoes that may liquefy and check test procedures for such cargoes.
- Ship owners/ operators are advised to be guided by above.
- Republic of Liberia marine advisory 02/2018.
This Technical Circular and the material contained in it is provided only for the purpose of supplying current information to the reader and not as an advice to be relied upon by any person. While we have taken utmost care to be as factual as possible, readers/ users are advised to verify the exact text and content of the Regulation from the original source/ issuing Authority.