scholarly journals Influence of Dispersed Oil on the Remote Sensing Reflectance—Field Experiment in the Baltic Sea

Sensors ◽  
2021 ◽  
Vol 21 (17) ◽  
pp. 5733
Author(s):  
Kamila Haule ◽  
Henryk Toczek ◽  
Karolina Borzycka ◽  
Mirosław Darecki
Keyword(s):  
Remote Sensing ◽  
Field Experiment ◽  
Baltic Sea ◽  
Oil Spills ◽  
Light Flux ◽  
Natural Seawater ◽  
Oil Droplets ◽  
Maximal Increase ◽  
Remote Sensing Reflectance ◽  
Dispersed Oil

Remote sensing techniques currently used to detect oil spills have not yet demonstrated their applicability to dispersed forms of oil. However, oil droplets dispersed in seawater are known to modify the local optical properties and, consequently, the upwelling light flux. Theoretically possible, passive remote detection of oil droplets was never tested in the offshore conditions. This study presents a field experiment which demonstrates the capability of commercially available sensors to detect significant changes in the remote sensing reflectance Rrs of seawater polluted by six types of dispersed oils (two crude oils, cylinder lubricant, biodiesel, and two marine gear lubricants). The experiment was based on the comparison of the upwelling radiance Lu measured in a transparent tank floating in full immersion in seawater in the Southern Baltic Sea. The tank was first filled with natural seawater and then polluted by dispersed oils in five consecutive concentrations of 1–15 ppm. After addition of dispersed oils, spectra of Rrs noticeably increased and the maximal increase varied from 40% to over three-fold at the highest oil droplet concentration. Moreover, the most affected Rrs band ratios and band differences were analyzed and are discussed in the context of future construction of algorithms for dispersed oil detection.

scholarly journals A Novel Experiment in the Baltic Sea Shows that Dispersed Oil Droplets Can Be Distinguished by Remote Sensing

Oceanography ◽  
2021 ◽  
pp. 60-61
Author(s):  
Kamila Haule ◽  
◽  
Włodzimierz Freda ◽  
Henryk Toczek ◽  
Karolina Borzycka ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Baltic Sea ◽  
The Baltic Sea ◽  
Oil Droplets ◽  
Dispersed Oil ◽  
The Baltic

OIL SPILL CLEANUP WITH DISPERSANTS: A BOOMED OIL SPILL EXPERIMENT

1981 ◽  
Vol 1981 (1) ◽  
pp. 263-268
Author(s):  
Joseph Buckley ◽  
David Green ◽  
Blair Humphrey
Keyword(s):  
Water Column ◽  
Oil Spill ◽  
Oil Spills ◽  
Sea Water ◽  
Visual Observation ◽  
Oil Droplets ◽  
Oil Boom ◽  
Dispersed Oil ◽  
Vertical Density ◽  
Oil Spill Cleanup

ABSTRACT Three experimental oil spills of 200, 400, and 200 litres (l) were conducted in October, 1978, in a semiprotected coastal area on Canada's west coast. The surface slicks were restrained with a Bennett inshore oil boom. The spilled oil was chemically dispersed using Corexit 9527, applied as a 10-percent solution in sea water and sprayed from a boat. The dispersed oil was monitored fluorometrically for some hours. Surface and dispersed oil were sampled for chemical analysis. The highest recorded concentration of dispersed oil was 1 part per million (ppm). After a short time (30 minutes), concentrations around 0.05 ppm were normal, decreasing to background within 5 hours. The concentrations were low compared to those expected for complete dispersion which, as visual observation confirmed, was not achieved. The dispersed oil did not mix deeper into the water column with the passage of time, in contrast to predicted behaviour and in spite of the lack of a significant vertical density gradient in the sea water. This was attributed to the buoyancy of the dispersed oil droplets and the limited vertical turbulence in the coastal locale of the experiment. The integrated quantity of oil in the water column decreased more rapidly than either the mean oil concentration of the cloud or the maximum concentration indicating that some of the dispersed oil was rising back to the surface. The surfacing of dispersed oil was confirmed visually during the experiment. The mixing action of the spray boat and breaker boards apparently created large oil droplets that did not form a stable dispersion. Horizontal diffusion of the dispersed oil was initially more rapid than expected, but the rate of spreading did not increase with time as predicted. The results imply that the scale of diffusion was larger than the scale of turbulence which again can be attributed to the locale of the experiment.

scholarly journals Effects of Chemical Dispersant on the Surface Properties of Kaolin and Aggregation with Spilled Oil

2021 ◽  
Author(s):  
Wenxin Li ◽  
Yue Yu ◽  
Deqi Xiong ◽  
Zhixin Qi ◽  
Sinan Fu ◽  
...  
Keyword(s):  
Crude Oil ◽  
Surface Properties ◽  
Oil Spills ◽  
Size Ratio ◽  
Small Scale ◽  
Oil Droplets ◽  
Mineral Aggregate ◽  
Chemical Dispersant ◽  
Dispersed Oil ◽  
Spilled Oil

Abstract After oil spills occur, dispersed oil droplets can collide with suspended particles in the water column to form the oil-mineral aggregate (OMA) and settle to the seafloor. However, only a few studies have concerned the effect of chemical dispersant on this process. In this paper, the mechanism by which dispersant affects the surface properties of kaolin as well as the viscosity and oil-seawater interfacial tension (IFTow) of Roncador crude oil were separately investigated by small scale tests. The results indicated that the presence of dispersant impairs the zeta potential and enhances the hydrophobicity of kaolin. The viscosity of Roncador crude oil rose slightly as the dosage of dispersant increased while IFTow decreased significantly. Furthermore, the oil dispersion and OMA formation at different dispersant-to-oil ratio (DOR) were evaluated in a wave tank. When DOR was less than 1:40, the oil enhancement of dispersant was not significant. In comparison, it began to contribute when DOR was over 1:40 and the effect became more pronounced with the increasing DOR. The adhesion between oil droplets and kaolin was inhibited with the increasing DOR. The size ratio between oil droplets and particles is the significant factor for OMA formation. The closer the oil-mineral size ratio is to 1, the more difficultly the OMA forms.

scholarly journals Laboratory measurements of remote sensing reflectance of selected phytoplankton species from the Baltic Sea

Oceanologia ◽  
2018 ◽  
Vol 60 (1) ◽  
pp. 86-96 ◽  
Author(s):  
Monika Soja-Woźniak ◽  
Mirosław Darecki ◽  
Bożena Wojtasiewicz ◽  
Katarzyna Bradtke
Keyword(s):  
Remote Sensing ◽  
Baltic Sea ◽  
Phytoplankton Species ◽  
Laboratory Measurements ◽  
The Baltic Sea ◽  
Remote Sensing Reflectance ◽  
The Baltic

SOME RECENT OBSERVATIONS REGARDING THE UNIQUE CHARACTERISTICS AND EFFECTIVENESS OF SELF-MIX CHEMICAL DISPERSANTS

1977 ◽  
Vol 1977 (1) ◽  
pp. 387-390
Author(s):  
Gerard P. Canevari
Keyword(s):  
Droplet Size ◽  
Oil Spills ◽  
Synergistic Effects ◽  
Toxic Substances ◽  
Mechanical Mixing ◽  
Oil Droplets ◽  
Dispersed Oil ◽  
Study Results ◽  
Micron Diameter ◽  
Spilled Oil

ABSTRACT There has been an increasing awareness of the utility of conventional chemical dispersants in general, and self-mix dispersants in particular as a viable means to minimize damage from oil spills. This paper will update the use of, and activity regarding the self-mix dispersant as noted in applications over the past two years. In addition, those aspects that are still little understood are discussed. Specifically, uniformly sized, dispersed oil droplets of approximately 1 micron diameter are formed by the diffusion action of self-mix chemical dispersants. The droplet size influences the dilution rate of the spilled oil in field applications, and data to support this are presented. The results of laboratory bioassays performed with these much smaller dispersed oil droplets, as opposed to larger droplets formed with mechanical mixing, can be misinterpreted since the increased rate of dilution afforded by smaller droplet size is not replicated. In addition to the vital dilution study results, this paper also presents evidence to clarify several popular misconceptions regarding chemical dispersants. For example, it is explained that the apparent synergistic effects between oil and dispersant do not indicate that chemical dispersants release toxic substances from the oil into the water. Data is also presented which shows that dispersants do not cause the oil to sink.

scholarly journals Modelling Remote Sensing Reflectance to Detect Dispersed Oil at Sea

Sensors ◽  
2020 ◽  
Vol 20 (3) ◽  
pp. 863 ◽  
Author(s):  
Emilia Baszanowska ◽  
Zbigniew Otremba ◽  
Jacek Piskozub
Keyword(s):  
Remote Sensing ◽  
Optical Properties ◽  
Spectral Index ◽  
Optical Parameters ◽  
Scattering Coefficients ◽  
Wind Speeds ◽  
Remote Sensing Reflectance ◽  
Dispersed Oil ◽  
The Monte Carlo Method ◽  
Oil In Water

This paper presents a model of upwelling radiation above the seawater surface in the event of a threat of dispersed oil. The Monte Carlo method was used to simulate a large number of solar photons in the water, eventually obtaining values of remote sensing reflectance (Rrs). Analyses were performed for the optical properties of seawater characteristic for the Gulf of Gdańsk (southern Baltic Sea). The case of seawater contaminated by dispersed oil at a concentration of 10 ppm was also discussed for different wind speeds. Two types of oils with extremely different optical properties (refraction and absorption coefficients) were taken into account for consideration. The optical properties (absorption and scattering coefficients and angular light scattering distribution) of the oil-in-water dispersion system were determined using the Mie theory. The spectral index for oil detection in seawater for different wind conditions was determined based on the results obtained for reflectance at selected wavelengths in the range 412–676 nm. The determined spectral index for seawater free of oil achieves higher values for seawater contaminated by oil. The analysis of the values of the spectral indices calculated for 28 combinations of wavelengths was used to identify the most universal spectral index of Rrs for 555 nm/440 nm for dispersed oil detection using any optical parameters.

Ultrasonic Scattering Measurements of Dispersed Oil Droplets in the Presence of Gas

2014 ◽  
Vol 2014 (1) ◽  
pp. 266-282 ◽  
Author(s):  
Paul D. Panetta ◽  
Dale McElhone ◽  
Kyle Winfield ◽  
Grace Cartwright
Keyword(s):  
Natural Gas ◽  
Water Column ◽  
Droplet Size ◽  
Oil Spills ◽  
Acoustic Scattering ◽  
Gas Bubbles ◽  
Deepwater Horizon ◽  
Oil Droplets ◽  
Large Wave ◽  
Dispersed Oil

ABSTRACT To help minimize the effects of oil spills on marine environments, chemical dispersants are used to disperse the oil in the water column so the oil can be consumed by naturally occurring bacteria. During the Deepwater Horizon incident, 1.1 million gallons of dispersant were injected directly into the flowing plume of oil and natural gas over 1500 meters deep. Dispersant's main effect is to decrease the surface tension at the oil-water interface causing the oil to form droplets smaller than ~70 microns so they can remain in the water column. Currently the efficacy of aerial applied dispersants on surface slicks is determined by measuring the droplet size decrease using a Laser In-Situ Scattering Transmissometer (LISST) or by detecting the oil in the water column using fluorometers. LISST instruments are limited to dilute mixtures, below ~500 ppm, because the LISST signal saturates for concentrated mixtures, and their windows can become occluded by oil and biofilms. Fluorometers only measure oil concentration; thus they cannot distinguish between naturally dispersed oil droplets, which can float back to the surface, from chemically dispersed oil droplets, which will remain in the water column to be naturally biodegraded. When gas is present as was the case in the Deepwater Horizon incident where it was estimated that the plume consisted of ~22% natural gas, the LISST cannot distinguish between oil droplets and gas bubbles and thus is not able to track the effectiveness of dispersants in the presence of gas. Acoustic measurements overcome the problems associated with the LISST and fluorometers and are ideal for applications subsurface near a blowout and for low ppm levels expected for surface slicks. One of the key features of the sound wave propagating through the water is the scattering at the interface between the water and object. In previous work we showed the proof of concept to measure the average oil droplet size using acoustic. We used the resonance behavior of the gas bubbles to identify them and separate their contribution to the measured acoustic scattering for various oil and dispersant combinations . We developed acoustic scattering and resonance measurements to track the size of oil droplets in the presence of gas during subsurface releases at SINTEF and in Ohmsett's large wave tank.

EFFECTS OF CHEMICAL DISPERSANTS AND MINERAL FINES ON PARTITIONING OF PETROLEUM HYDROCARBONS IN NATURAL SEAWATER

2008 ◽  
Vol 2008 (1) ◽  
pp. 633-638 ◽  
Author(s):  
Kenneth Lee ◽  
Zhengkai Li ◽  
Thomas King ◽  
Paul Kepkay ◽  
Michel C Boufadel ◽  
...  
Keyword(s):  
Crude Oil ◽  
Water Column ◽  
Petroleum Hydrocarbons ◽  
Oil Spills ◽  
Suspended Sediments ◽  
Bulk Water ◽  
Natural Seawater ◽  
Dispersed Oil ◽  
Aliphatic And Aromatic Hydrocarbons ◽  
Mineral Aggregates

ABSTRACT The interaction of chemical dispersants and suspended sediments with crude oil influences the fate and transport of oil spills in coastal waters. Recent wave tank studies have shown that dispersants facilitate the dissipation of oil droplets into the water column and reduces the particle size distribution of oil-mineral aggregates (OMAs). In this work, baffled flasks were used to carry out a controlled laboratory experimental study to define the effects of chemical dispersants and mineral fines on the partitioning of crude oil, major fractions of oil, and petroleum hydrocarbons from the surface to the bulk water column and the sediment phases. The dissolved and dispersed oil in the aqueous phase and OMA was characterized using an Ultraviolet Fluorescence Spectroscopy (UVFS). The distribution of major fractions of crude oil (the alkanes, aromatics, resins, and asphaltenes) was analyzed by thin layer chromatography coupled to flame ionized detection (TLC/FID); aliphatic and aromatic hydrocarbons were analyzed by gas chromatography and mass spectrometry (GC/MS). The results suggest that chemical dispersants enhanced the transfer of oil from the surface to the water column as dispersed oil, and promoted the formation of oil-mineral aggregates in the water column. Interaction of chemically dispersed oil with suspended particular materials needs to be considered in order to accurately assess the environmental risk associated with chemical oil dispersant use in particle-rich nearshore and esturine waters. The results from this study indicate that there is not necessarily an increase in sedimentation of oil in particle rich water when dispersants are applied.

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