Modelling of the rate of oil spill disappearance from seawater for Kuwaiticrude and its products

In this paper a semi-analytical model has been developed to estimate the am ount of oil disappeared from an oil spill floating on seawater surface. The model considers evaporation, dissolution and sedimentation of oil componen ts. Crude oil and wide boiling range fractions are divided into several pse udocomponents using distribution model developed by Riazi (Ind. Eng. Chem. Res., 36 (10) (1997) 4299-4307). Heavy components with densities above dens ity of water, sink to the bottom of sea while light components vaporize or dissolve into water. In the model, oil spill thickness is considered variab le versus time. The input data for the model are distillation data (or comp osition) for oil, API gravity of oil, initial volume of oil spill, initial area of oil spill, air temperature, wind speed and water surface velocity. The only adjustable parameter is a constant in the relation for the mass tr ansfer coefficient for evaporation. The model estimates area, volume and co mposition of oil spill versus time. It also calculates the amount of oil va porized, dissolved or sunk into water versus time. Three sets of experiment s were conducted for a Kuwaiti export crude oil and four different Kuwaiti petroleum products also used for export to determine the rate of oil disapp earance at ambient temperature. Data obtained in these experiments were use d to determine the model parameter as well as evaluation of the proposed mo del. (C) 1999 Elsevier Science S.A. All rights reserved.