Progress toward the development of micro- and meso-scale methods for predicting the behavior of low-API gravity oils (LAPIO) spilled on water

Bench-scale weathering studies were conducted on a number of low-API gravity oils (LAPIO), and flume tank studies were conducted on several LAPIO products. The objective was to develop a method which would predict the environmental behaviour of LAPIO fuel spilled on water. Unlike crude oils and petroleum products which float when spilled on water, LAPIO spills are unpredictable. LAPIO fuels, which are used for electric power generation, have densities greater or equal to 1.0 g/ml. When spilled at sea, they may float, be neutrally buoyant, or sink, depending on the conditions of the receiving water. Their behavior depends on the physical and chemical properties of the specific oil and also the temperature and composition of the water. In order to simulate the behavior of oil spilled at sea, a number of different LAPIO fuels were artificially weathered by evaporative distillation. Tests were conducted to determine the physical and chemical properties of the oil residues, the buoyancy of the oils, their emulsifying properties and chemical dispersability. Results have shown that current laboratory methods for determining emulsion formation, stability, and kinetics are not adequate for these highly viscous fuels. Laboratory methods need refining and improving. 7 refs