Demulsifiers are liquids which break up water-in-oil emulsions that have been recovered onshore or at sea.
products, with a high concentration of polar compounds,
which undergo agitation in the presence of water (natural
wave action, travelling through a skimmer pump...) form
reverse emulsions by incorporating droplets of water in
the oil phase. These emulsions can contain up to 80% water
and are sticky, viscous masses, brown to dark brown in
colour, which explains why they are often known as "chocolate
The formation of reverse emulsions, along with the evaporation of the lighter fractions, strongly influences the viscosity of an oil pollutant during weathering at sea. The viscosity of the crude oil from the Amoco Cadiz multiplied by 200 due to the formation of an emulsion containing 75% water. Emulsification significantly increases the volume of pollution and thus complicates operations. The incorporation of 75% of water in the Amoco Cadiz oil meant that the volume of pollution was muliplied by four.