125
© Springer Nature Switzerland AG 2020
S. A. Murawski et al. (eds.), Deep Oil Spills,
https://doi.org/10.1007/978-3-030-11605-7_8
Chapter 8
Partitioning of Organics Between Oil
and Water Phases with and Without
the Application of Dispersants
Aprami Jaggi, Ryan W. Snowdon, Jagoš R. Radović, Andrew Stopford,
Thomas B. P. Oldenburg, and Steve R. Larter
Abstract Immediately following an oil spill, more hydrophilic and toxic oil compounds such as benzene, toluene, ethylbenzene, and xylene (BTEX) partition
from the oil into the water phase. The partitioning behavior of individual organic
compounds between petroleum and water phases is influenced by their molecular
properties and by the pressure, the temperature, and the composition of bulk oil
and surrounding water. The traditional shake flask technique for determining oilwater partition ratios (equilibrium [X] oil /[X] water ) cannot accurately assess the
extremes of high pressure and low water temperatures found in deep submarine
oil spill conditions. To address that challenge, an oil-water partitioning device
was constructed to experimentally simulate the partition behavior of BTEX compounds under submarine oil spill conditions, using simulated live oil (methane
charged) with saline waters, over a range of pressure (2–15 MPa) and temperature
(4–20 °C). Within the investigated ranges, the partition ratios of BTEX compounds increase proportionally with an increase in methane charging pressure (oil
saturation pressure) and the degree of alkylation within the BTEX compound
group. The increase in experimental temperature, however, resulted in a decrease
in the partition ratios of BTEX compounds. The change of the partition ratio values, due to changes in system pressure and increasing methane concentration, is
much more significant than the changes that are due to varying temperature over
the range studied.
The customized system was also operated with chemical dispersant, which is
often applied as a spill response option to enhance the natural dispersion of oil following spillage, to understand its effect on the partitioning of oil at an oil/dispersant ratio of 1000:1. The addition of dispersants was found to increase the extent
of BTEX compound partitioning from the oil into water. The increase observed
A. Jaggi (*) · R. W. Snowdon · J. R. Radović · A. Stopford · T. B. P. Oldenburg · S. R. Larter
University of Calgary, PRG, Department of Geoscience, Calgary, AB, Canada
e-mail: aprami.jaggi@ucalgary.ca; rwsnowdo@ucalgary.ca; jagos.radovic@ucalgary.ca;
toldenbu@ucalgary.ca; slarter@ucalgary.ca
© Springer Nature Switzerland AG 2020
S. A. Murawski et al. (eds.), Deep Oil Spills,
https://doi.org/10.1007/978-3-030-11605-7_8
Chapter 8
Partitioning of Organics Between Oil
and Water Phases with and Without
the Application of Dispersants
Aprami Jaggi, Ryan W. Snowdon, Jagoš R. Radović, Andrew Stopford,
Thomas B. P. Oldenburg, and Steve R. Larter
Abstract Immediately following an oil spill, more hydrophilic and toxic oil compounds such as benzene, toluene, ethylbenzene, and xylene (BTEX) partition
from the oil into the water phase. The partitioning behavior of individual organic
compounds between petroleum and water phases is influenced by their molecular
properties and by the pressure, the temperature, and the composition of bulk oil
and surrounding water. The traditional shake flask technique for determining oilwater partition ratios (equilibrium [X] oil /[X] water ) cannot accurately assess the
extremes of high pressure and low water temperatures found in deep submarine
oil spill conditions. To address that challenge, an oil-water partitioning device
was constructed to experimentally simulate the partition behavior of BTEX compounds under submarine oil spill conditions, using simulated live oil (methane
charged) with saline waters, over a range of pressure (2–15 MPa) and temperature
(4–20 °C). Within the investigated ranges, the partition ratios of BTEX compounds increase proportionally with an increase in methane charging pressure (oil
saturation pressure) and the degree of alkylation within the BTEX compound
group. The increase in experimental temperature, however, resulted in a decrease
in the partition ratios of BTEX compounds. The change of the partition ratio values, due to changes in system pressure and increasing methane concentration, is
much more significant than the changes that are due to varying temperature over
the range studied.
The customized system was also operated with chemical dispersant, which is
often applied as a spill response option to enhance the natural dispersion of oil following spillage, to understand its effect on the partitioning of oil at an oil/dispersant ratio of 1000:1. The addition of dispersants was found to increase the extent
of BTEX compound partitioning from the oil into water. The increase observed
A. Jaggi (*) · R. W. Snowdon · J. R. Radović · A. Stopford · T. B. P. Oldenburg · S. R. Larter
University of Calgary, PRG, Department of Geoscience, Calgary, AB, Canada
e-mail: aprami.jaggi@ucalgary.ca; rwsnowdo@ucalgary.ca; jagos.radovic@ucalgary.ca;
toldenbu@ucalgary.ca; slarter@ucalgary.ca