Studies of in-situ burning of emulsions in Norway

Abstract

An experimental program, spanning four years, was initiated in 1990 to study the in-situ burning of emulsions. Its main objectives were to study the in-situ burning of emulsions in dynamic conditions (wind, wave, currents, and ice); to define the limitations and effectiveness of in-situ burning in terms of water content, evaporation, and film thickness of crude oils and emulsions; and to determine the physical processes involved in burning water-in-oil emulsions. Field experiments were conducted in basins cut into sea ice ranging in size from 4 m2 to 300 m2. Small-scale pan burns and emulsion-heating experiments were conducted in the laboratory. The results show that evaporated water-free oil can be easily ignited and burned with a high efficiency, even in the presence of swells and slush ice. When water contents exceeded 25 percent, the emulsions were difficult to ignite using gelled gasoline, and could not be ignited in the presence of moderate swells. However; ignition could be improved by using alternative igniters. Some postulated processes on the burning of stable emulsions have been confirmed: water must be removed from the emulsion surface before ignition can occur, water is released mainly through evaporation, and the temperature in the emulsion slick does not seem to exceed the boiling point of water.