Weathering of Oil Spill: Modeling and Analysis

Oil spill releases a large amount of crude oil on sea surface. Once the crude oil is spilled, it gradually starts decaying under the influence of concurrent processes collectively termed as oil weathering processes (OWP). Weathering of an oil slick modifies its behavior making it more persistent to marine waters and enduring its lifespan in marine biology. Hence in order to plan an effective response operation, it is vital to have advance knowledge of oil slick behavior. The mathematical representations of OWP are therefore used to predict critical slick properties such as viscosity and density. In addition, an improved understanding of OWP evolved over the years provides an ample opportunity to examine the existing relationships and subsequently to incorporate the required changes. The aim of present paper was to model and analyze effects of initial oil properties on its behavior, immediately after the spill. For this purpose three different crude oils: heavy, intermediate and light were selected. Runge-Kutta fourth order method was used to solve spreading, evaporation, dissolution and emulsification OWP simultaneously. Results indicate that light and intermediate oil uptakes more water than heavy crude oil with time. Hence, the volume for clean-up is expected to be high in case of light and intermediate crude oil spills. Moreover, evaporation and emulsification were found to be extremely sensitive to initial oil viscosity and composition.