RECENT ADVANCES IN DISPERSANT EFFECTIVENESS EVALUATION: EXPERIMENTAL AND FIELD ASPECTS

Abstract

ABSTRACT Although dispersants are used in different countries, it appeared from recent international meetings that more knowledge concerning dispersant effectiveness is still needed for a better response to oil spills. Large field trials which were conducted during the past two years raised some questions as to how dispersants work at sea. Even though the results obtained in different laboratory tests are generally in good accord, significant discrepancies of practical interest may be observed because of variations in the experimental conditions. With EEC support, an experimental program has been conducted by CEDRE and Institut Français du Pétrole (IFP), both with the already-described French middle scale field test and with different laboratory tests (U.K. and French standard tests and the recently developed dilution test). With the objective of correlating the results obtained in field tests and in laboratory tests, several parameters were investigated at sea with different dispersants: the type and viscosity of the oil, slick thickness, and oil to dispersant ratio. Based mainly on the results obtained in the laboratory with dilution tests, new aspects of dispersant behavior have been identified, relating to the nature of the oil and the energy input.