155
© Springer Nature Switzerland AG 2020
S. A. Murawski et al. (eds.), Deep Oil Spills,
https://doi.org/10.1007/978-3-030-11605-7_10
Chapter 10
Effects of Oil Properties and Slick
Thickness on Dispersant Field
Effectiveness and Oil Fate
Marieke Zeinstra-Helfrich and Albertinka J. Murk
Abstract One of the available oil spill response options is to enhance the natural
dispersion process by the addition of dispersants known as chemical dispersion. An
informed decision for such response requires insight about the added effects of
treatment with dispersants on the oil slick fate. To provide such insight, a mathematical model for oil slick elongation as a result of dispersion was developed
including the effects of oil viscosity, dispersed oil droplet sizes, and oil layer thickness. This chapter briefly revisits this oil slick elongation model to explain the
consequences of different key parameters on dispersion, vertical droplet size distribution, formation of a comet-like tail and oil slick (dis)appearance, as well as the
implications of the results for future decision-making. The model outcomes indicate that wind speed is a very dominant factor in dispersion and subsequent slick
behavior. More surprising, the influence of oil type on the elongation process is
only limited. The increased density of the high-viscosity oil types allows larger
droplets to be stably suspended. High-viscosity oil, however, was found to benefit
less from a decrease in interfacial tension than a low-viscosity oil. Weighing estimated risks for adverse effects in the water column with a reduced surface oil presence allows for future dispersant decisions based on a thorough Spill Impact
Mitigation Analysis (SIMA).
Keywords Dispersion · Dispersant · Spill modelling · Wind speed · Oil type
M. Zeinstra-Helfrich (*)
NHL Stenden University of Applied Sciences, Leeuwarden, The Netherlands
e-mail: m.zeinstra@nhl.nl
A. J. Murk
Wageningen University, Marine Animal Ecology Group, Wageningen, The Netherlands
e-mail: Tinka.murk@wur.nl
© Springer Nature Switzerland AG 2020
S. A. Murawski et al. (eds.), Deep Oil Spills,
https://doi.org/10.1007/978-3-030-11605-7_10
Chapter 10
Effects of Oil Properties and Slick
Thickness on Dispersant Field
Effectiveness and Oil Fate
Marieke Zeinstra-Helfrich and Albertinka J. Murk
Abstract One of the available oil spill response options is to enhance the natural
dispersion process by the addition of dispersants known as chemical dispersion. An
informed decision for such response requires insight about the added effects of
treatment with dispersants on the oil slick fate. To provide such insight, a mathematical model for oil slick elongation as a result of dispersion was developed
including the effects of oil viscosity, dispersed oil droplet sizes, and oil layer thickness. This chapter briefly revisits this oil slick elongation model to explain the
consequences of different key parameters on dispersion, vertical droplet size distribution, formation of a comet-like tail and oil slick (dis)appearance, as well as the
implications of the results for future decision-making. The model outcomes indicate that wind speed is a very dominant factor in dispersion and subsequent slick
behavior. More surprising, the influence of oil type on the elongation process is
only limited. The increased density of the high-viscosity oil types allows larger
droplets to be stably suspended. High-viscosity oil, however, was found to benefit
less from a decrease in interfacial tension than a low-viscosity oil. Weighing estimated risks for adverse effects in the water column with a reduced surface oil presence allows for future dispersant decisions based on a thorough Spill Impact
Mitigation Analysis (SIMA).
Keywords Dispersion · Dispersant · Spill modelling · Wind speed · Oil type
M. Zeinstra-Helfrich (*)
NHL Stenden University of Applied Sciences, Leeuwarden, The Netherlands
e-mail: m.zeinstra@nhl.nl
A. J. Murk
Wageningen University, Marine Animal Ecology Group, Wageningen, The Netherlands
e-mail: Tinka.murk@wur.nl