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A-DROP: A predictive model for the formation of oil particle aggregates (OPAs)

Lin Zhao·Michel C. Boufadel·Xiaolong Geng·Kenneth Lee·Thomas King·Brian H. Robinson·Faith A. Fitzpatrick
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Abstract

Oil–particle interactions play a major role in removal of free oil from the water column. We present a new conceptual–numerical model, A-DROP, to predict oil amount trapped in oil–particle aggregates. A new conceptual formulation of oil–particle coagulation efficiency is introduced to account for the effects of oil stabilization by particles, particle hydrophobicity, and oil–particle size ratio on OPA formation. A-DROP was able to closely reproduce the oil trapping efficiency reported in experimental studies. The model was then used to simulate the OPA formation in a typical nearshore environment. Modeling results indicate that the increase of particle concentration in the swash zone would speed up the oil–particle interaction process; but the oil amount trapped in OPAs did not correspond to the increase of particle concentration. The developed A-DROP model could become an important tool in understanding the natural removal of oil and developing oil spill countermeasures by means of oil–particle aggregation.

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Lin Zhao, Michel C. Boufadel, Xiaolong Geng, Kenneth Lee, Thomas King, Brian H. Robinson, Faith A. Fitzpatrick. 2016. A-DROP: A predictive model for the formation of oil particle aggregates (OPAs). https://doi.org/10.1016/j.marpolbul.2016.02.057

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