During the maritime transport of bulk dry cargo, phenomena may arise that will affect the stability of the vessel. One of the most concerning is dynamic separation, which in recent years is increasingly recognized as a cause of maritime accidents. But what is dynamic separation?
Dynamic separation manifests at sea when the moisture trapped in the cargo begins to move toward its surface. This process is accelerated by the movements and vibrations of the vessel, as the cargo gradually acquires a solid form from the bottom upward. The phenomenon is mainly observed in cargoes consisting of fine particles, which retain moisture within them.
As the vessel sails, a slurry of water and small particles forms on the surface of the cargo. This slurry creates a free surface, causing moments of inertia that negatively affect stability. If these moments synchronize with the vessel’s movements, the slurry can shift to one side, causing a permanent tilt and severe loss of stability.
To reduce the risk of dynamic separation, certain amendments to the IMSBC Code were adopted in May 2019. These amendments now explicitly require the assessment of this specific risk through proper and timely cargo sampling, accurate moisture measurement, and continuous monitoring of the cargo during the voyage.
Source: Britannia P&I Club
