CHARACTERIZATION OF CRUDE OILS FOR ENVIRONMENTAL PURPOSES

A new approach for predicting the behaviour of oil spilled on the sea has recently been developed at IKU, Sintef-Group. The approach includes an extensive laboratory investigation of an oil's properties when exposed to weathering. Parameters especially tested are the tendency of the oil to form water-in-oil (w/o) emulsion (mousse), and the susceptibility of the w/o-emulsion or water-free weathered oil to disperse using oil spill dispersants. The laboratory results are transformed to field conditions in a numerical model which predicts the rate of weathering processes at sea under different weather conditions. The computer system displays graphical charts for the development of each property with time, and estimates the 'time window' e.g. for effective application of dispersants under a chosen set of sea conditions. The system may represent an important tool, for contingency planning and for 'on-scene' commanders to facilitate decision-making concerning the use of different countermeasure techniques during oil spill combat operations. This approach may form the basis for a standard method for future characterization of the weathering properties of different oil types which may be spilled under a variety of environmental conditions.