There is widespread concern in the shipping industry that the soon to be implemented Indonesian ban on raw ore exports could lead to liquefaction and sinking of ships. Indonesia is one of the main suppliers of raw ore to China, and the impending ban of ore exports from Indonesia is thought to have contributed to a number of vessels capsizing and sinking.
In 2010, three vessels from Indonesia sank in less than a month, with loss of all goods and personnel on board. The sinking of these vessels was allegedly caused by overloading of the ships, in an attempt to transport as much raw ore as possible from Indonesia before the ban comes into effect. The ban, which was initially meant to be instituted in 2014, has been advanced to 2012, leading to panic in the shipping export industry.
Increased pressure to load ships with as much ore as possible before the May 2012 deadline has lead to a number of shipping tragedies in the last few months. More cargo inevitably leads to more pressure on the ship masters, ship surveyors and crew members, as well as fraudulent documentation that claim that cargo ships are within their weight limits, while being in reality grossly overloaded. Responsible P and I clubs have attempted to take measures to ensure that the ship surveyors continue to do a professional job, but other clubs have questionable track records and continue to issue fraudulent documents, particularly regarding moisture in cargo.
Moisture is an important factor to consider for cargo carrying ships. As water is non-compressible, it acts as a lubricant between divided particles. Cargo containing a high moisture content can act like fluid in bad weather conditions, flowing to one side of the hold and locking in place. The result of this is a permanent listing of the ship, which can lead to capsize in a matter of minutes.
The speed at which a vessel collapses under conditions of liquefaction often leaves no time for distress calls, meaning that often the only evidence of liquefaction is sudden disappearance of the vessel, its cargo and its crew. Even with sophisticated technologies such as AIS and EPIRBS, liquefaction remains a common cause of vessel capsize.
There have been a number of incidents of vessels sinking since 2009 which have been thought to be due to this phenomenon. Most cases of liquefaction occur in the Pacific, during the rainy season when cargos retain high moisture levels.
