Abstract
To provide fundamental information for the design of a response plan when accidental spills of an emulsified fuel (Orimulsion) occur, a laboratory-scale study was carried out On the fuel's behavior in saline, quiescent waters. The emulsifier in the fuel was made ineffective, when the fuel was dispersed in saline waters. The degree of ineffectiveness increased with an increase in salinity of the water. As a result, the droplets in Orimulsion coalesced with each other shortly after being dispersed in saline water. Most of the coalesced bitumen drops were finally re-floated when dispersed in seawater. This re-floated amount depended on the salinity of the saline water. Although in the saline water with a density from 1.012 to 1.015g/cm3 at 15°C, the re-floated part of the bitumen drops dominated, there was also found a significant part deposited on the floor. This deposited part of the bitumen in Orimulsion was relatively unsticky, and was considered to be the asphaltic fraction of the bitumen. The presence of this sinking part in the bitumen will make the behavior of Orimulsion further complicated when it is spilled in an estuary area.
