Bauxite Liquefaction

What is Cargo Liquefaction ?

The most severe stability dangers for a bulk carrier are caused by cargoes that may shift during the voyage.  This condition is known as cargo liquefaction. It describes the phenomenon where some cargoes may liquefy due to their natural characteristics, allowing accumulation and humidity migration. The most well-known case of such cargo is bauxite. The shift can adversely affect the ship’s stability, structure, and crew safety.

Notable Accident Cases

M/V Bulk Jupiter, Bulk Carrier, (56,009dwt, built 2006) en route from Kuantan, Malaysia, to China, issued distress signals at 22:54 hours UTC on January 1st in position lat 9”,01’ 01:00N, long 109” 15’ 26.01E. The vessel departed Kuantan on December 30th 2014 at around 20:00 hours local time, with 19 crewmembers, all Filipinos, on board and about 46,400 mts of bauxite in bulk, stowed in all five of her cargo holds. The vessel capsized and sank about 150 nm off the coast of Viet Nam. One survivor was rescued.

Master’s Warning

The IMO has set a list of bulk materials that may behave like liquids in the International Maritime Solid Bulk Cargoes (IMSBC) Code. However, these characteristics may not be clarified in shipment documents. For this reason, IMO warns ship Masters not to accept such cargoes and particular bauxite for carriage unless:

• the moisture limit for the specific cargo is certified as less than the indicative moisture limit of 10% and the particle size distribution as is detailed in the individual schedule for Bauxite in the IMSBC Code; or
• the cargo is declared as Group A (cargoes that may liquefy) and the shipper declares the transportable moisture limit (TML) and moisture content; or
• the cargo has been assessed as not presenting Group A properties.

Can Test

Suppose a ship’s master suspects excessive moisture in cargo. In that case, he may contact a can test during loading with the presence of a P&I surveyor, preferably. This test cannot verify the content of water. Still, if it fails, this will be objective evidence that water in the commodity is excessive and should not be loaded.

UK P&I Club has produced some videos in partnership with global cargo experts Minton Treharne & Davis (MTD). These videos explain what a can test is and what it looks like in practice.