Nickel Ore Liquefaction - A Reminder

The Club is aware of several incidents in the last few months where liquefaction of nickel ore cargo loaded in the Philippines, and in particular Surigao, has resulted in vessels experiencing problems at sea or during loading.

The ban on the export of unprocessed nickel ore from Indonesia is still in place. The carriage of lateritic ores such as nickel ore is problematic. Nickel ore is a cargo which may liquefy if the moisture content of the material exceeds its Transportable Moisture Limit (TML). Cargo liquefaction may lead to a loss of stability, to the extent that the ship may capsize.

It is typical in these incidents that the TML and moisture content of the cargo declared by the shippers is incorrect.

Vigilance

It is only through the vigilance of the ships’ Master and officers, and any surveyor appointed to assist them, that unsafe cargo can be prevented from being loaded on board.

Regular and frequent can tests are a ‘must do’ with nickel ore cargoes but it should be remembered that these tests cannot indicate whether a cargo is safe. They are just one of the Master’s or surveyor’s tools for assessing the risk posed by the cargo.

Another important part of the toolkit is close observation and tracking of cargo operations. In a recent incident a vessel’s Master was concerned about the amount of splattering observed in the hold from a cargo of nickel ore being loaded.

As a result more frequent can tests were ordered and subsequent barges of cargo were rejected. The rejection of barges continued to a point where the vessel refused to accept any more cargo until more detailed tests were carried out on the cargo.

Testing of the rejected cargo revealed that not only was the TML of the cargo substantially lower than that declared, but the moisture content was actually well in excess of both the TML and Flow Moisture Point (FMP) of the cargo. As such the cargo was unsafe to load.

Sun Drying

One factor has been common to several incidents where barges have been rejected. The cargo, whilst still in the barge, has then undergone a process known in the trade as ‘sun drying’. This process can only dry the surface of the cargo, it is simply not possible to dry the entirety of the cargo out in a matter of a few hours or days whilst it is still in the barge.

A dry crust forms which may allow can tests of surface material to be passed but the majority of the cargo remains wet below the surface. This practice is dangerous – rejected barges should have the cargo replaced and the new cargo should be checked to ensure that is suitable for carriage.

More Information

It is important that the vessel’s crew remain vigilant and be guided by the advice contained within the IMSBC code and our loss prevention publications. Members may find the following publications useful when dealing with nickel ore cargo.

LP Briefing

Nickel Ore

Hot-Spots

/media/72814/Hot-Spots-Liquefaction.PDF

Posters

/media/493380/NORTH-Cargo-wise-Poster-Liquefaction-.pdf

Members are also reminded of our Circulars in relation to loading nickel ore and the requirement to notify the Club when planning to load nickel ore from the Philippines
or Indonesia.

Circular Ref: 2012/023 – Dangers of Carrying Nickel Ore from Indonesia and the Philippines
– Mandatory Notification Requirements.

Circular Ref: 2011/009 – Indonesia and the Philippines – Safe Carriage of Nickel Ore
Cargoes.

www.nepia.com/circulars