Light Refined Oils Discharged on Water Surface

Abstract

Light refined oil products, such as naphtha, gasoline, kerosene and gas oil have been included among the objects of the “International Convention for Prevention of Pollution from Ships, 1973” by IMCO. However, there have been few studies on the dispersion and weathering processes of these oils.
The purpose of the paper are an experimental estimation of evaporation rates and solubilities of the light oils in closed separatory funnels and an open water tank, and a quantitative analysis of optical characteristics of thin oil films on water surface.
The higher values of evaporation rate from oil slicks are obtained in order of naphtha, gasoline, kerosene, crude oil (Iranian light) and gas oil on the same conditions of air velocity, air temperature and water temperature.
It is indicated from gas chromatography analysis that the aqueous fractions mainly consist of light parafin and light aromatic hydrocarbons. In the open water tank system, the contents of dissolved fractions into water phase are estimated to be almost the same order for gasoline, kerosene and crude oil, and have a tendency of increasing as a decrease of the air velocity.
From the study on reflectivity and the result of observing the colour of oil film under daylight, it is shown that the“silvery sheen”state corresponds to the first occurrence of an optical interference in the colour range of blue violet.