Experimental Study on the Synergistic Effect between Evaporation Weathering and Emulsification of Oil Spills

Abstract

First, a range of experiments using a stainless steel shallow plate in a thermostatic oscillator were carried out to simulate evaporation weathering of oil spills under different temperatures, wind velocities, oil film thicknesses, and wave conditions. The information on influencing factors of evaporation weathering could be obtained. Then, evaporation experiments of four oil samples with three emulsification states were conducted, and the effect of emulsification on evaporation of oil spills was investigated. The characteristics of each operation were described, mass loss characteristics of oil spills with time were plotted, and the effects of evaporative weathering processes under different conditions were quantitatively compared. A high-precision visualization system was utilized to simulate experimentally oil spill emulsification processes, and the effect of evaporative weathering on emulsification weathering of oil spills was investigated. The results of evaporation experiments showed that the increase of temperature could promote the evaporative weathering. The thin film thickness was beneficial to evaporation of oil spills. The increment of the wind speed could promote evaporation behavior when the wind velocity was small, but the increase of velocity had little effect on oil evaporation when the wind speed was large. Wave conditions had little effect on oil evaporation under the conditions of this experiment. The effect of different emulsification states on oil evaporation was not consistent. Unstable or semistable water-in-oil emulsions inhibited oil evaporation at the initial stage of evaporation, but water evaporation would increase oil-phase evaporation with the destruction of the emulsion structure. Stable water-in-oil emulsions inhibited evaporation weathering. The evaporation weathering of oil was conducive to the emulsification of oil.