Induction of hsp60 in the rotifer, Brachionus plicatilis exposed to dispersed and undispersed crude oil

International Nuclear Information System (INIS)

Wheelock, C.; Tjeerdema, R.; Wolfe, M.

1995-01-01

The use of chemical dispersants to treat oil spills remains a controversial area. Questions arise as to whether the dispersed oil is in fact more toxic than the original spill, potentially increasing the exposure of organisms in the water column to the dispersed components. Stress proteins, including hsp60, are a group of highly conserved proteins that are induced in response to a wide variety of environmental agents, including UV light, heavy metals, and xenobiotics. They are constitutively expressed, but Brachionus plicatilis has been used to document increased hsp60 levels in response to different environmental stresses. Hsp60 was therefore selected as a sublethal endpoint for B. plicatilis exposed to a range of concentrations of a water accommodated fraction (WAF) of Prudhoe Bay Crude Oil (PBCO), a PCBO/dispersant (Corexit 9527) fraction and a mixture of Corexit 9527 alone. All exposures were done at concentrations below the no observable effect level (NOEL) and at two different salinities, 22 ppt and 34 ppt. Laemmli SDS-PAGE techniques followed by Western Blotting using hsp60 specific antibodies and chemiluminescent detection were used to isolate, identify and measure induced hsp60 as a percentage of control values. Hsp60 induction exhibited a biphasic response with maximal induction occurring at lower concentrations of all three different mixtures, WAF, PBCO/Corexit 9527, and Corexit 9527 alone. Preliminary data found that the dispersed oil is indeed more toxic in terms of hsp60 induction than both the undispersed oil and the dispersing agent alone

Induction of hsp60 in the rotifer, Brachionus plicatilis exposed to dispersed and undispersed crude oil

Energy Technology Data Exchange (ETDEWEB)

Wheelock, C.; Tjeerdema, R.; Wolfe, M. [Univ. of California, Santa Cruz, CA (United States). Dept. of Chemistry and Biochemistry

1995-12-31

The use of chemical dispersants to treat oil spills remains a controversial area. Questions arise as to whether the dispersed oil is in fact more toxic than the original spill, potentially increasing the exposure of organisms in the water column to the dispersed components. Stress proteins, including hsp60, are a group of highly conserved proteins that are induced in response to a wide variety of environmental agents, including UV light, heavy metals, and xenobiotics. They are constitutively expressed, but Brachionus plicatilis has been used to document increased hsp60 levels in response to different environmental stresses. Hsp60 was therefore selected as a sublethal endpoint for B. plicatilis exposed to a range of concentrations of a water accommodated fraction (WAF) of Prudhoe Bay Crude Oil (PBCO), a PCBO/dispersant (Corexit 9527) fraction and a mixture of Corexit 9527 alone. All exposures were done at concentrations below the no observable effect level (NOEL) and at two different salinities, 22 ppt and 34 ppt. Laemmli SDS-PAGE techniques followed by Western Blotting using hsp60 specific antibodies and chemiluminescent detection were used to isolate, identify and measure induced hsp60 as a percentage of control values. Hsp60 induction exhibited a biphasic response with maximal induction occurring at lower concentrations of all three different mixtures, WAF, PBCO/Corexit 9527, and Corexit 9527 alone. Preliminary data found that the dispersed oil is indeed more toxic in terms of hsp60 induction than both the undispersed oil and the dispersing agent alone.

Application of ultraviolet fluorometry and excitation-emission matrix spectroscopy (EEMS) to fingerprint oil and chemically dispersed oil in seawater.

Science.gov (United States)

Bugden, J B C; Yeung, C W; Kepkay, P E; Lee, K

2008-04-01

Excitation-emission matrix spectroscopy (EEMS) was used to characterize the ultra violet fluorescence fingerprints of eight crude oils (with a 14,470-fold range of dynamic viscosity) in seawater. When the chemical dispersant Corexit 9500 was mixed with the oils prior to their dispersion in seawater, the fingerprints of each oil changed primarily as an increase in fluorescence over an emission band centered on 445 nm. In order to simplify the wealth of information available in the excitation-emission matrix spectra (EEMs), two ratios were calculated. A 66-90% decrease in the slope ratio was observed with the addition of Corexit. When the slope ratios were reduced in complexity to intensity ratios, similar trends were apparent. As a result either of the ratios could be used as a simple and rapid means of identifying and monitoring chemically dispersed oil in the open ocean.

Partitioning of fresh crude oil between floating, dispersed and sediment phases: Effect of exposure order to dispersant and granular materials.

Science.gov (United States)

Boglaienko, Daria; Tansel, Berrin

2016-06-15

When three or more high and low energy substrates are mixed, wetting order can significantly affect the behavior of the mixture. We analyzed the phase distribution of fresh floating Louisiana crude oil into dispersed, settled and floating phases depending on the exposure sequence to Corexit 9500A (dispersant) and granular materials. In the experiments artificial sea water at salinity 34‰ was used. Limestone (2.00-0.300 mm) and quartz sand (0.300-0.075 mm) were used as the natural granular materials. Dispersant Corexit 9500A increased the amount of dispersed oil up to 33.76 ± 7.04%. Addition of granular materials after the dispersant increased dispersion of oil to 47.96 ± 1.96%. When solid particles were applied on the floating oil before the dispersant, oil was captured as oil-particle aggregates and removed from the floating layer. However, dispersant addition led to partial release of the captured oil, removing it from the aggregated form to the dispersed and floating phases. There was no visible oil aggregation with the granular materials when quartz or limestone was at the bottom of the flask before the addition of oil and dispersant. The results show that granular materials can be effective when applied from the surface for aggregating or dispersing oil. However, the granular materials in the sediments are not effective neither for aggregating nor dispersing floating oil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effectiveness of dispersants on thick oil slicks

International Nuclear Information System (INIS)

Ross, S.; Belore, R.

1993-01-01

Experiments were conducted to determine the relationship between dispersant effectiveness and oil slick thickness, and thereby determine the optimum time for applying dispersant onto spilled oil at sea. Tests were completed at a lab-scale level by varying the three parameters of oil type, dispersant application, and oil thickness. The tests were intended to be comparative only. The primary oils used were Alberta sweet mix blend and Hibernia B-27 crude. The dispersant, Corexit 9527, was applied either premixed with the oil, dropwise in one application, or dropwise in multiple applications to simulate a multi-hit aircraft operation. The apparatus used in the experiment was an oscillating hoop tank, with oil-containing rings used to obtain and maintain uniform slick thickness. The results indicate that the effectiveness potential of a chemical dispersant does not decrease as slick thickness increases. In fact, results of the tests involving Hibernia oil suggest that oils that tend to herd easily would be treated more effectively if dispersant were applied when the oil was relatively thick (1 mm or greater) to avoid herding problems. The oil slicks premixed with dispersant did not disperse well in the thick oil tests, not because of dispersant-oil interaction problems but because of reduced mixing energy. 6 refs., 4 figs., 1 tab

COREXIT 9580 shoreline cleaner: Development, application, and status

International Nuclear Information System (INIS)

Canevari, G.P.; Fiocco, R.J.; Lessard, R.R.; Fingas, M.

1995-01-01

This paper will describe research on chemical beach cleaners for treatment of oiled shorelines that was initiated in support of the cleaning activities in Prince William Sound (PWS) following the Valdez oil spill in March 1989. The concept for using beach cleaners for shoreline cleanup is to apply a pre-soak to the weathered crude oil on shore and then flush with sea water to wash the oil into a boomed area for subsequent recovery. Criteria imposed on the use of chemical beach cleaners for the cleanup of the Valdez spill were: (1) effective rock cleaning agents should have very little or no toxicity to marine and terrestrial life, (2) there should be no dispersion of the oil washed from the shoreline into the water column; oil was to be recovered by techniques such as skimming or sorbents, and (3) the agents should be on the EPA National Contingency Plan (NCP) list. A laboratory-scale rock washing test was developed to measure cleaner effectiveness and dispersion. A large number of commercially available formulated products were evaluated, as well as development formulations. The commercial products included all of the available NCP-listed products which could function as cleaners. None of the commercial products completely satisfied all the requirements established by the agencies for beach cleaning. However, a new formula, called COREXIT 9580, consisting of two surfactants and a solvent was developed. It exhibited low fish toxicity, low dispersancy and effective rock cleaning capability. The paper reviews the laboratory and field testing to explore the potential use of the COREXIT 9580 to save and restore oiled vegetation

Effect of Two Oil Dispersants on Larval Grass Shrimp (Palaemonetes pugio) Development.

Science.gov (United States)

Betancourt, P.; Key, P. B.; Chung, K. W.; DeLorenzo, M. E.

2015-12-01

The study focused on the effects that two oil dispersants, Corexit® EC9500A and Finasol® OSR52, have on the development of larval grass shrimp, (Palaemonetes pugio). The hypothesis was that Finasol would have a greater effect on larval grass shrimp development than Corexit. The experiment was conducted using 300 grass shrimp larvae that were 24 hours old. Each larva was exposed individually. In total, five sub-lethal concentrations were tested for each dispersant (control, 1.25, 2.50, 5.0,10.0 mg/L). The larvae were exposed for five days then transferred to clean seawater until metamorphosis into the juvenile stage. Key data measurements recorded included number of days to become juveniles, number of instars, length, dry weight, and mortality. Data from exposed shrimp was compared to the results of the control for each dispersant concentration. Corexit and Finasol exposure treatments of 5 mg/L and 10 mg/L showed significantly higher values for number of days and number of instars to reach juvenile status than values obtained from unexposed, control shrimp. Overall, mortality was higher in the Finasol treatments but the two dispersants did not respond significantly different from one another. Future studies are needed to determine the long term effects of dispersant exposure on all grass shrimp life stages and how any dispersant exposure impacts grass shrimp populations. Grass shrimp serve as excellent toxicity indicators of estuaries, and further studies will help to develop better oil spill mitigation techniques.

Generation of shrimp waste-based dispersant for oil spill response.

Science.gov (United States)

Zhang, Kedong; Zhang, Baiyu; Song, Xing; Liu, Bo; Jing, Liang; Chen, Bing

2018-04-01

In this study, shrimp waste was enzymatically hydrolyzed to generate a green dispersant and the product was tested for crude oil dispersion in seawater. The hydrolysis process was first optimized based on the dispersant effectiveness (DE) of the product. The functional properties of the product were identified including stability, critical micelle concentration, and emulsification activity. Water was confirmed as a good solvent for dispersant generation when compared with three chemical solvents. The effects of salinity, mixing energy, and temperature on the dispersion of the Alaska North Slope (ANS) crude oil were examined. Microtox acute toxicity test was also conducted to evaluate the toxicity of the produced dispersant. In addition, DE of the product on three different types of crude oil, including ANS crude oil, Prudhoe Bay crude oil (PBC), and Arabian Light crude oil (ALC) was compared with that of the Corexit 9500, respectively. The research output could lead to a promising green solution to the oil spill problem and might result in many other environmental applications.

The effects of short term exposure to Bass Strait crude oil and Corexit 8667 on benthic community metabolism in Posidonia australis Hook. f. dominated microcosms

Energy Technology Data Exchange (ETDEWEB)

Hatcher, A.I.; Larkum, A.W.D.

1982-03-01

Microcosms consisting of a sublittoral seagrass meadow from Botany Bay, N.S.W. were maintained in aquaria in a controlled environment room from March to August 1979. Oxygen production and consumption in the microcosms and leaf turnover of the seagrass, Posidonia australis Hook.f. were measured before, during and after a 7-day treatment in June with Bass Strait crude oil and the dispersant Corexit 8667. Four microcosms received oil and two of these received dispersant. The leaf turnover of P. australis was not significantly affected by the addition of oil and dispersant. Photosynthetic oxygen production decreased and respiration increased in the microcosms during treatment. In August, 40 days after treatment, oxygen production rates and P/R ratios in the oil-treated microcosms were higher than rates measured before treatment. The oil-and-dispersant-treated microcosms did not show this trend. The results of this study indicate that a more severe stress is placed on the P. australis dominated benthic community by oil and dispersant than by oil alone.

Acute and chronic toxicity study of the water accommodated fraction (WAF), chemically enhanced WAF (CEWAF) of crude oil and dispersant in the rock pool copepod Tigriopus japonicus.

Science.gov (United States)

Lee, Kyun-Woo; Shim, Won Joon; Yim, Un Hyuk; Kang, Jung-Hoon

2013-08-01

We determined the toxicity of the water accommodated hydrocarbon fraction (WAF), two chemically enhanced WAFs (CEWAFs; CEWAF-C, Crude oil+Corexit 9500 and CEWAF-H, Crude oil+Hiclean) of crude oil and two dispersants (Corexit 9500 and Hiclean) to the rock pool copepod Tigriopus japonicus. In the acute toxicity test, Corexit 9500 was the most toxic of all the chemicals studied. The nauplius stage of T. japonicus was more susceptible to the toxic chemicals studied than the adult female. The toxicity data using the nauplius stage was then considered as baseline to determine the spiking concentration of chemicals for chronic toxicity tests on the copepod. As the endpoints in the chronic toxicity test, survival, sex ratio, developmental time and fecundity of the copepod were used. All chemicals used in this study resulted in increased toxicity in the F1 generation. The lowest-observed-adverse-effect (LOAE) concentrations of WAF, CEWAF-H, CEWAF-C, Hiclean and Corexit 9500 were observed to be 50%, 10%, 0.1%, 1% and 1%, respectively. The results in present study imply that copepods in marine may be negatively influenced by spilled oil and dispersant. Copyright © 2013 Elsevier Ltd. All rights reserved.

Chemical dispersants

NARCIS (Netherlands)

Rahsepar, Shokouhalsadat; Smit, Martijn P.J.; Murk, Albertinka J.; Rijnaarts, Huub H.M.; Langenhoff, Alette A.M.

2016-01-01

Chemical dispersants were used in response to the Deepwater Horizon oil spill in the Gulf of Mexico, both at the sea surface and the wellhead. Their effect on oil biodegradation is unclear, as studies showed both inhibition and enhancement. This study addresses the effect of Corexit on oil

Effects of temperature and wave conditions on chemical dispersion efficacy of heavy fuel oil in an experimental flow-through wave tank.

Science.gov (United States)

Li, Zhengkai; Lee, Kenneth; King, Thomas; Boufadel, Michel C; Venosa, Albert D

2010-09-01

The effectiveness of chemical dispersants (Corexit 9500 and SPC 1000) on heavy fuel oil (IFO180 as test oil) has been evaluated under different wave conditions in a flow-through wave tank. The dispersant effectiveness was determined by measuring oil concentrations and droplet size distributions. An analysis of covariance (ANCOVA) model indicated that wave type and temperature significantly (p or = 400 microm). Copyright 2010 Elsevier Ltd. All rights reserved.

Effects of pollution by oil and oil-dispersants on the common intertidal polychaetes, Cirriformia tentaculata and Cirratulus cirratus

Energy Technology Data Exchange (ETDEWEB)

George, J D

1971-08-01

An oil spill occurred from the Marine terminal of the Esso refinery at Fawley, England, where oil-polluted mudflats at the Hamble River mouth contained populations of Cirriformia tentaculata and Cirratulus cirratus. Quantitative studies on Cirriformia tentaculata and semi-quantitative studies of Cirratulus cirratus showed that spawning, growth, and mortality were unaffected by the oil. Reasons for the oil's ineffectiveness in disrupting life processes were discussed. On mudflats where Essolvene dispersant was used to remove oil from boats and shore installtions, number of both species decreased. Toxicity tests using Essolvene and BP 1002 showed that both species were killed by low concentrations of dispersant: C. cirratus was more tolerant, BP 1002 was most toxic. These populations showed recovery signs 2 yr after pollution. Tests showed a new dispersant, Corexit 7664, was less toxic than Essolvene and BP 1002, although all prevented gamete formation in C. cirratus at concentrations approaching the lethal level.

Bioavailability of chemically-dispersed crude oil

International Nuclear Information System (INIS)

Harris, B.C.; Bonner, J.S.; McDonald, T.J.; Fuller, C.B.; Page, C.A.; Dimitriou-Christidis, P.; Sterling, M.C.; Autenrieth, R.L.

2002-01-01

Oil spills can be treated with surfactant compounds to disperse them. This method enables the hydrophobic compounds to overcome their repulsion for water, enter the water phase and be diluted. Once in the water, the biodegradation fraction of the oil biodegrades over time and the residual fraction is deposited over a large area. One major issue which is not fully understood is whether oil compounds pass through the water phase to free floating cells or directly enter oil-attached microbial cells from the oil particle. In this study, crude oil was placed in a swirling flask with Corpus Christi Bay water and was then chemically dispersed with Corexit 9500. The biodegradation was then monitored and assessed. First order rate coefficients were determined based on the disappearance of specific compounds. The rate coefficients for total target PAHs were consistent for all tests. Napthalene, phenanthrene, dibenzothiophene and their alkylated homologs were among the target compounds. The trend was also observed for total target analytes and for total target saturates. The results indicate that the biodegradation rate coefficient was not dependent on the bulk concentration of oil in the water column. It was concluded that biodegradation rates was controlled by partitioning of the compounds between the two phases, and other factors such as particle size distribution and the capability of the microbial culture, temperature and nutrients. 13 refs., 1 tab., 6 figs

Measuring the aerial application of oil dispersant from very large aircraft at moderate altitude

International Nuclear Information System (INIS)

Fay, R.R.; Giammona, C.P.; Binkley, K.; Engelhardt, F.R.

1993-01-01

As part of a study of various aspects of oil dispersant application technology, a comparison study was conducted employing the Airborne Dispersant Delivery System (ADDS) pack and the Modular Aerial Spray System (MASS) in C-130 Hercules aircraft at altitudes of 50-150 ft above ground and at speeds up to 200 knots. Dyed Corexit 9527 was applied at a target dose rate of 5 gal/acre over a collection grid composed of metal trays, Kromekote cards, oil-sensitive cards, a continuous trough, and a WRK string collector. Analysis of the collected dispersant was done by colorimetry, fluorometry, and image analysis. Correlations through the different methodologies demonstrated that high speed, moderate altitude application of oil dispersant could be successful in delivering dispersant to the surface at effective concentration and drop size. Environmental studies of the test area showed no residual dispersant in the soil following cessation of spraying. 1 ref

Evaluation of three oil spill laboratory dispersant effectiveness tests

International Nuclear Information System (INIS)

Sullivan, D.; Farlow, J.; Sahatjian, K.A.

1993-01-01

Chemical dispersants can be used to reduce the interfacial tension of floating oil slicks so that the oils disperse more rapidly into the water column and thus pose less of a threat to shorelines, birds, and marine mammals. The laboratory test currently specified in federal regulations to measure dispersant effectiveness is not especially easy or inexpensive, and generates a rather large quantity of oily waste water. This paper describes the results of an effort by the EPA to identify a more suitable laboratory dispersant effectiveness test. EPA evaluated three laboratory methods: the Revised Standard Dispersant Effectiveness Test currently used (and required by regulation) in the United States, the swirling flask test (developed by Environment Canada), and the IFP-dilution test (used in france and other European countries). Six test oils and three dispersants were evaluated; dispersants were applied to the oil at an average 1:10 ratio (dispersant to oil) for each of the three laboratory methods. Screening efforts were used to focus on the most appropriate oil/dispersant combination for detailed study. A screening criterion was established that required a combination that gave at least 20% effectiveness results. The selected combination turned out to be Prudhoe Bay crude oil and the dispersant Corexit 9527. This combination was also most likely to be encountered in US coastal waters. The EPA evaluation concluded that the three tests gave similar precision results, but that the swirling flask test was fastest, cheapest, simplest, and required least operator skill. Further, EPA is considering conducting the dispersant effectiveness test itself, rather than having data submitted by a dispersant manufacturer, and establishing an acceptability criterion (45% efficiency) which would have to be met before a dispersant could be placed on the Product Schedule of the National Contingency Plan (NCP)

Corexit 9500 Enhances Oil Biodegradation and Changes Active Bacterial Community Structure of Oil-Enriched Microcosms

OpenAIRE

Techtmann, Stephen M.; Zhuang, Mobing; Campo, Pablo; Holder, Edith; Elk, Michael; Hazen, Terry C.; Conmy, Robyn; Santo Domingo, Jorge W.

2017-01-01

To better understand the impacts of Corexit 9500 on the structure and activity levels of hydrocarbon-degrading microbial communities, we analyzed next-generation 16S rRNA gene sequencing libraries of hydrocarbon enrichments grown at 5 and 25°C using both DNA and RNA extracts as the sequencing templates. Oil biodegradation patterns in both 5 and 25°C enrichments were consistent with those reported in the literature (i.e., aliphatics were degraded faster than aromatics). Slight increases in bio...

Oil spill dispersants induce formation of marine snow by phytoplankton-associated bacteria.

Science.gov (United States)

van Eenennaam, Justine S; Wei, Yuzhu; Grolle, Katja C F; Foekema, Edwin M; Murk, AlberTinka J

2016-03-15

Unusually large amounts of marine snow, including Extracellular Polymeric Substances (EPS), were formed during the 2010 Deepwater Horizon oil spill. The marine snow settled with oil and clay minerals as an oily sludge layer on the deep sea floor. This study tested the hypothesis that the unprecedented amount of chemical dispersants applied during high phytoplankton densities in the Gulf of Mexico induced high EPS formation. Two marine phytoplankton species (Dunaliella tertiolecta and Phaeodactylum tricornutum) produced EPS within days when exposed to the dispersant Corexit 9500. Phytoplankton-associated bacteria were shown to be responsible for the formation. The EPS consisted of proteins and to lesser extent polysaccharides. This study reveals an unexpected consequence of the presence of phytoplankton. This emphasizes the need to test the action of dispersants under realistic field conditions, which may seriously alter the fate of oil in the environment via increased marine snow formation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of oil dispersants on photodegradation of pyrene in marine water

Energy Technology Data Exchange (ETDEWEB)

Gong, Yanyan [Environmental Engineering Program, Department of Civil Engineering, Auburn University, Auburn, AL 36849 (United States); College of Environmental Science and Engineering, Nankai University, Tianjin 300071 (China); Fu, Jie [Environmental Engineering Program, Department of Civil Engineering, Auburn University, Auburn, AL 36849 (United States); O’Reilly, S.E. [U.S. Department of the Interior, Gulf of Mexico OCS, Office of Environment, New Orleans, LA 70123 (United States); Zhao, Dongye, E-mail: zhaodon@auburn.edu [Environmental Engineering Program, Department of Civil Engineering, Auburn University, Auburn, AL 36849 (United States)

2015-04-28

Highlights: • Oil dispersant enhances pyrene photodegradation in seawater. • Oil dispersant increases formation of superoxide radicals. • Pyrene photodegradation shows a two-stage kinetics and follows first-order rate law. • Pyrene is degraded mainly through electron transfer from excited pyrene to oxygen. • Higher ionic strength and temperature and lower HA favor pyrene photodegradation. - Abstract: This work investigated effects of a popular oil dispersant (Corexit EC9500A) on UV- or sunlight-mediated photodegradation of pyrene (a model polycyclic aromatic hydrocarbon) in seawater. The presence of 18 and 180 mg/L of the dispersant increased the first-order photodegradation rate by 5.5% and 16.7%, respectively, and reduced or ceased pyrene volatilization. By combining individual first-order rate laws for volatilization and photodegradation, we proposed an integrated kinetic model that can adequately predict the overall dissipation of pyrene from seawater. Mechanistic studies indicated that superoxide radicals played a predominant role in pyrene photodegradation, and the dispersant enhanced formation of superoxide radicals. 1-Hydroxypyrene was the main intermediate regardless of the dispersant, suggesting that electrons were transferred from excited pyrene to oxygen. In the presence of 18 mg/L of the dispersant, the photodegradation rate increased with increasing ionic strength and temperature, but decreased with increasing HA concentration, and remained independent of solution pH. The results are important in understanding roles of oil dispersants on environmental fate of persistent oil components in natural and engineered systems.

Influence of UVB radiation on the lethal and sublethal toxicity of dispersed crude oil to planktonic copepod nauplii.

Science.gov (United States)

Almeda, Rodrigo; Harvey, Tracy E; Connelly, Tara L; Baca, Sarah; Buskey, Edward J

2016-06-01

Toxic effects of petroleum to marine zooplankton have been generally investigated using dissolved petroleum hydrocarbons and in the absence of sunlight. In this study, we determined the influence of natural ultraviolet B (UVB) radiation on the lethal and sublethal toxicity of dispersed crude oil to naupliar stages of the planktonic copepods Acartia tonsa, Temora turbinata and Pseudodiaptomus pelagicus. Low concentrations of dispersed crude oil (1 μL L(-1)) caused a significant reduction in survival, growth and swimming activity of copepod nauplii after 48 h of exposure. UVB radiation increased toxicity of dispersed crude oil by 1.3-3.8 times, depending on the experiment and measured variables. Ingestion of crude oil droplets may increase photoenhanced toxicity of crude oil to copepod nauplii by enhancing photosensitization. Photoenhanced sublethal toxicity was significantly higher when T. turbinata nauplii were exposed to dispersant-treated oil than crude oil alone, suggesting that chemical dispersion of crude oil may promote photoenhanced toxicity to marine zooplankton. Our results demonstrate that acute exposure to concentrations of dispersed crude oil and dispersant (Corexit 9500) commonly found in the sea after oil spills are highly toxic to copepod nauplii and that natural levels of UVB radiation substantially increase the toxicity of crude oil to these planktonic organisms. Overall, this study emphasizes the importance of considering sunlight in petroleum toxicological studies and models to better estimate the impact of crude oil spills on marine zooplankton. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Spill-of-opportunity testing of dispersant effectiveness at the Mega Borg oil spill

International Nuclear Information System (INIS)

Payne, J.R.; Martrano, R.J.; Reilly, T.J.; Lindblom, G.P.; Kennicutt, M.C. II; Brooks, J.M.

1993-01-01

The release of 3.9 million gallons of Angola Planca crude oil from the stricken tanker Mega Borg 57 miles offshore of Galveston, Texas in June 1990 provided a valuable opportunity to document dispersant effectiveness under field conditions. Aerial application of Corexit 9527 (968 gallons total in four adjacent passes) onto an identified test portion of the slick was evaluated by concurrent observations from a command-and-control aircraft and surface vessels (with videotape and 35-mm photographic documentation) and ground truth measurements, including continuous 4-meter-depth ultraviolet/fluorescence and a discrete water sampling program. Using the study plan outlined by Payne and colleagues, target and control areas were designated before dispersant application by deployment of smoke bombs and coded three-meter drogues. Postdispersant surface vessel placement and 30 liter water sampling activities from the Texas A ampersand M research vessel HOS Citation were aided by the smoke bombs, the free-drifting drogues, and directions from the command-and-control aircraft. Subsequent FID GC and GC/MS analyses of water sample extracts allowed quantitation of the dispersed oil concentrations under both treated and control areas. Although the spilled oil was extremely light (API gravity 39.0) and subject to significant natural dispersion, the field observations, filmed documentation, and water column data clearly demonstrated an increase in dispersed oil concentrations beneath the treated slick. The distribution of dispersed oil droplets was very heterogeneous and reflected the patchy distribution of oil on the water surface before dispersant application. Maximum concentrations of dispersed hydrocarbons in the center of the treated zone were 22,000 μg/L (22 ppm) for total aliphatic and 5.6 μg/L (5.6 ppb) for total aromatics 60 to 90 minutes after dispersant application. Elevated levels were generally limited to the upper 1 to 3 meters of the water column

Tests for oil/dispersant toxicity: In situ laboratory assays

International Nuclear Information System (INIS)

Wright, D.A.; Coelho, G.M.; Aurand, D.V.

1995-01-01

As part of its readiness program in oil spill response, the Marine Pollution Control Unit (MPCU), Department of Transport, U.K. conducts annual field trials in the North Sea, approximately 30 nautical miles from the southeast coast of England. The trials take the form of controlled releases of crude oil or Medium Fuel/Gas Oil mix (MFO), with and without the application of Corexit 9527 dispersant. In 1994 and 1995 the authors conducted a series of in situ toxicity bioassays in association with these spills with included 48h LC50 tests for turbot (Scophthalmus maximus) and oyster (Crassostrea gigas) larvae, a 48 h oyster (C. gigas) embryonic development test and two full life-cycle assays using the copepods Acartia tonsa and Tisbe battagliai. Tests were also conducted in the Chesapeake Bay laboratory using estuarine species including the copepod Eurytemora affinis and the inland silverside Menidia beryllina. Here, the authors report on the results of these assays, together with 1996 in situ toxicity data resulting from Norwegian field trials in the northern North Sea

Phototoxic potential of undispersed and dispersed fresh and weathered Macondo crude oils to Gulf of Mexico Marine Organisms.

Science.gov (United States)

Finch, Bryson E; Marzooghi, Solmaz; Di Toro, Dominic M; Stubblefield, William A

2017-10-01

Crude oils contain a mixture of hydrocarbons, including phototoxic polycyclic aromatic hydrocarbons (PAHs) that have the ability to absorb ultraviolet (UV) light. Absorption of UV light by PAHs can substantially increase their toxicity to marine organisms. The objective of the present study was to examine the potential for phototoxicity of fresh and naturally weathered Macondo crude oils alone and in combination with the dispersant Corexit 9500 to mysid shrimp (Americamysis bahia), inland silverside (Menidia beryllina), sheepshead minnow (Cyprinodon variegatus), and Gulf killifish (Fundulus grandis). Acute toxicity tests were conducted using combinations of natural or artificial sunlight and low-energy water-accommodated fractions (WAFs) of fresh and weathered Macondo crude oils collected from the Gulf of Mexico. Studies were also conducted to compare the phototoxicity resulting from natural and artificial sunlight. Fresh Macondo crude oil was more phototoxic than weathered crude oils, both in the presence and in the absence of UV light. Differences in toxicity between fresh and weathered crude oils were likely attributed to lighter-ringed PAHs in fresh crude oils. Phototoxic PAHs were relatively resistant to weathering compared with lighter-ringed PAHs. The addition of Corexit 9500 to crude oil increased toxicity compared with tests with crude oil alone, by increasing phototoxic PAH concentrations in WAFs. Macondo crude oils had the potential to be phototoxic to Gulf of Mexico marine organisms if specific light conditions and PAH concentrations were present during the Deepwater Horizon oil spill. Environ Toxicol Chem 2017;36:2640-2650. © 2017 SETAC. © 2017 SETAC.

Natural sunlight shapes crude oil-degradingbacterial communities in northern Gulf of Mexico surface waters

Directory of Open Access Journals (Sweden)

Hernando P Bacosa

2015-12-01

Full Text Available Following the Deepwater Horizon (DWH spill in 2010, an enormous amount of oil was observed in the deep and surface waters of the northern Gulf of Mexico. Surface waters are characterized by intense sunlight and high temperature during summer. While the oil-degrading bacterial communities in the deep-sea plume have been widely investigated, the effect of natural sunlight on those in oil polluted surface waters remains unexplored to date. In this study, we incubated surface water from the DWH site with amendments of crude oil, Corexit dispersant, or both for 36 d under natural sunlight in the northern Gulf of Mexico. The bacterial community was analyzed over time for total abundance, density of alkane and polycyclic aromatic hydrocarbon degraders, and community composition via pyrosequencing. Our results showed that, for treatments with oil and/or Corexit, sunlight significantly reduced bacterial diversity and evenness and was a key driver of shifts in bacterial community structure. In samples containing oil or dispersant, sunlight greatly reduced abundance of the Cyanobacterium Synechococcus but increased the relative abundances of Alteromonas, Marinobacter, Labrenzia, Sandarakinotalea, Bartonella, and Halomonas. Dark samples with oil were represented by members of Thalassobius, Winogradskyella, Alcanivorax, Formosa, Pseudomonas, Eubacterium, Erythrobacter, Natronocella, and Coxiella. Both oil and Corexit inhibited the Candidatus Pelagibacter with or without sunlight exposure. For the first time, we demonstrated the effects of light in structuring microbial communities in water with oil and/or Corexit. Overall, our findings improve understanding of oil pollution in surface water, and provide unequivocal evidence that sunlight is a key factor in determining bacterial community composition and dynamics in oil polluted marine waters.

Natural Sunlight Shapes Crude Oil-Degrading Bacterial Communities in Northern Gulf of Mexico Surface Waters.

Science.gov (United States)

Bacosa, Hernando P; Liu, Zhanfei; Erdner, Deana L

2015-01-01

Following the Deepwater Horizon (DWH) spill in 2010, an enormous amount of oil was observed in the deep and surface waters of the northern Gulf of Mexico. Surface waters are characterized by intense sunlight and high temperature during summer. While the oil-degrading bacterial communities in the deep-sea plume have been widely investigated, the effect of natural sunlight on those in oil polluted surface waters remains unexplored to date. In this study, we incubated surface water from the DWH site with amendments of crude oil, Corexit dispersant, or both for 36 days under natural sunlight in the northern Gulf of Mexico. The bacterial community was analyzed over time for total abundance, density of alkane and polycyclic aromatic hydrocarbon degraders, and community composition via pyrosequencing. Our results showed that, for treatments with oil and/or Corexit, sunlight significantly reduced bacterial diversity and evenness and was a key driver of shifts in bacterial community structure. In samples containing oil or dispersant, sunlight greatly reduced abundance of the Cyanobacterium Synechococcus but increased the relative abundances of Alteromonas, Marinobacter, Labrenzia, Sandarakinotalea, Bartonella, and Halomonas. Dark samples with oil were represented by members of Thalassobius, Winogradskyella, Alcanivorax, Formosa, Pseudomonas, Eubacterium, Erythrobacter, Natronocella, and Coxiella. Both oil and Corexit inhibited the Candidatus Pelagibacter with or without sunlight exposure. For the first time, we demonstrated the effects of light in structuring microbial communities in water with oil and/or Corexit. Overall, our findings improve understanding of oil pollution in surface water, and provide unequivocal evidence that sunlight is a key factor in determining bacterial community composition and dynamics in oil polluted marine waters.

The effectiveness of dispersants under various temperature and salinity regimes

International Nuclear Information System (INIS)

Fingas, M.; Fieldhouse, B.; Wang, Z.; Environment Canada, Ottawa, ON

2005-01-01

A series of tests were conducted to determine the effectiveness of dispersants in Arctic waters where salinity and temperature interactions play a critical role. In particular, Corexit 9500 was tested on Alaska North Slope oil at different temperatures and salinity using the ASTM standard test and variations of this test. Results were compared to the only historically reported test in which both temperature and salinity were changed over a range of values. This series of tests demonstrated that there is an interaction between salinity, temperature and dispersant effectiveness. It was shown that conventional and currently available dispersants are nearly ineffective at 0 salinity. Dispersant effectiveness peaks at 20 to 40 units of salinity, depending on the type of dispersant. Corexit is less sensitive to salinity, while Corexit 9527 is more sensitive to salinity. There is a smooth gradient of effectiveness with salinity both as the salinity rises to a peak point of effectiveness and as it exceeds this value. Results from the 2 field trials in fresh water suggest that laboratory tests correctly conclude that the effectiveness of dispersants is very low in freshwater. The study also examined several analytical factors such as the total petroleum hydrocarbon (TPH) versus relative petroleum hydrocarbon (RPH) methods, specific versus general calibration curves, and automatic versus manual baseline placement. The analytical variations of effectiveness by RPH or TPH methods do not affect the fundamental relationship between salinity and temperature. 6 refs., 6 tabs., 8 figs

Ophthalmic effects of petroleum dispersant exposure on common murres (Uria aalge): An experimental study.

Science.gov (United States)

Fiorello, Christine V; Freeman, Kate; Elias, Becky A; Whitmer, Emily; Ziccardi, Michael H

2016-12-15

The safety of chemical dispersants used during oil spill responses is largely unknown in birds. We captured common murres in Monterey Bay, CA and exposed them to Corexit EC9500a, crude oil, or a combination in artificial seawater. We performed ophthalmic examinations and measured intraocular pressures and tear production before and after exposure. Loglinear analysis found that exposure to oil or dispersant was related to the development of conjunctivitis and corneal ulcers. Odds ratios for birds exposed to oil or dispersant were positive and significant for the development of conjunctivitis, while odds ratios for the development of corneal ulcers were positive and significant only for birds exposed to a high concentration of oil. Ocular exposure to dispersants and petroleum in seabirds may cause conjunctivitis and may play a role in the development of corneal ulcers. These results have implications for policymakers who develop protocols for the use of dispersants during marine oil spills. Copyright © 2016 Elsevier Ltd. All rights reserved.

A literature review of the variation of dispersant effectiveness and salinity

International Nuclear Information System (INIS)

Fingas, M.

2005-01-01

Surfactants have varying solubilities in water and varying actions toward oil and water. This paper presents a summary of the effects of water salinity on chemical dispersion. Literature reveals that effectiveness testing with salinity variations shows a consistent decrease in effectiveness at lower salinities and a decrease after a maximum salinity is reached between 20 to 40 units of salinity. In waters with 0 salinity, conventional and currently available dispersants have a very low effectiveness or are sometimes even completely ineffective, a fact which is consistent in surfactant literature. Dispersant effectiveness peaks in waters with a salinity ranging from 20 to 40. Corexit 9500 appears to be less sensitive to salinity, but still peaks at about 35. There is a relatively smooth gradient of effectiveness with salinity both as the salinity rises to a peak point of effectiveness and after it exceeds this value. The curves for this salinity effect appear to be Gaussian. While there is some evidence for a temperature-salinity interaction as noted in the data, there is not enough data to make solid conclusions. Recent data is almost exclusively measured using Corexit 9527 and Corexit 9500. Since these have the same surfactant packages, there is a concern that the results may be more relevant to these formulations than to all possible formulations. Observations on 2 field trials in freshwater appear to indicate that the laboratory tests were correct in concluding very low dispersant effectiveness in freshwater. There were few studies on the biological effects of varying salinity and given oil exposure. It was concluded that the findings in the dispersant literature reviewed here are in agreement with those in the theoretical and basic surfactant literature. The effect of ionic strength and salinity on both hydrophilic-lipophilic balance and stability is the reason for the decreased effectiveness noted at low salinities and the same decrease at high salinities

Influence of dispersants on petroleum bioavailability in a marine food chain

International Nuclear Information System (INIS)

Wolfe, M.F.; Younghans-Haug, C.O.; Tjeerdema, R.S.; Sowby, M.L.

1994-01-01

Oil spills represent a serious threat to marine organisms. Crude oil consists of numerous compounds with a wide range of physicochemical properties critical in determining those organisms at greatest risk. Surface inhabitants may benefit from the application of dispersing agents, yet little is understood of the disposition of the dispersed components of a spill. As the functional water solubility of petroleum hydrocarbons increases in the water column, the portion that is available for uptake may also increase, placing another group of organisms at risk. Potential increases in adsorption and bioaccumulation may extend the threat of oil spills from marine organisms to human consumers. Studies to date have focused on the acute toxicity of oil and dispersants. The objective of this research was to determine the influence of a dispersant on the bioavailability of crude oil components at concentrations below the no observable effect level (NOEL). Flow-through chambers were used to expose the algae, Isochrysis galbana, to ''undispersed'' Prudhoe Bay Crude Oil (PBCO) spiked with 14 C naphthalene and ''dispersed'' spiked PBCO/Corexit 9527 sea water preparations. Bioavailability to Isochrysis was assessed as uptake, bioconcentration, and deputation of 14 C naphthalene and its metabolites. Results of exposure studies will be presented

Influence of dispersants on trophic transfer of petroleum hydrocarbons in a marine food chain

Energy Technology Data Exchange (ETDEWEB)

Wolfe, M.; Tjeerdema, R. [Univ. of California, Santa Cruz, CA (United States). Dept. of Chemistry and Biochemistry; Sowby, M. [California Dept. of Fish and Game, Sacramento, CA (United States)

1995-12-31

When crude oil is accidentally released into the ocean, it threatens many levels of marine life. Intervention, in the form of chemical dispersing agents, alters the normal behavior of petroleum hydrocarbons (PH) by increasing their functional water solubility and the extent of their exposure to sub-surface organisms. Dispersing agents may modify bioavailability as a result of altered interactions between dispersed PH droplets and organismal cell membranes.The objective of this research was to determine the impact of dispersing agents on PH bioavailability and trophic transfer in primary levels of a marine food chain. Uptake, bioaccumulation, depuration, and metabolic transformation of a model PH, {sup 14}C-naphthalene, were measured and compared for Prudhoe Bay Crude Oil (PBCO) dispersed with Corexit 9527 and undispersed preparations of the water-accommodated fractions (WAF) of PBCO at two salinities and temperatures. The model food chain consisted of Isochrysis galbana and Brachionus plicatilis. Direct aqueous exposure was compared with combined aqueous and dietary exposure. Fractionation and identification of metabolites was done by HPLC co-chromatography with analytical standards, and quantitation was done by liquid scintillation counting. GC-FID characterization of WAF and dispersed oil (DO) preparations shows higher concentrations of petroleum hydrocarbons and a greater number of individual constituents in the dispersed oil preparations.

Influence of dispersants on trophic transfer of petroleum hydrocarbons in a marine food chain

International Nuclear Information System (INIS)

Wolfe, M.; Tjeerdema, R.

1995-01-01

When crude oil is accidentally released into the ocean, it threatens many levels of marine life. Intervention, in the form of chemical dispersing agents, alters the normal behavior of petroleum hydrocarbons (PH) by increasing their functional water solubility and the extent of their exposure to sub-surface organisms. Dispersing agents may modify bioavailability as a result of altered interactions between dispersed PH droplets and organismal cell membranes.The objective of this research was to determine the impact of dispersing agents on PH bioavailability and trophic transfer in primary levels of a marine food chain. Uptake, bioaccumulation, depuration, and metabolic transformation of a model PH, 14 C-naphthalene, were measured and compared for Prudhoe Bay Crude Oil (PBCO) dispersed with Corexit 9527 and undispersed preparations of the water-accommodated fractions (WAF) of PBCO at two salinities and temperatures. The model food chain consisted of Isochrysis galbana and Brachionus plicatilis. Direct aqueous exposure was compared with combined aqueous and dietary exposure. Fractionation and identification of metabolites was done by HPLC co-chromatography with analytical standards, and quantitation was done by liquid scintillation counting. GC-FID characterization of WAF and dispersed oil (DO) preparations shows higher concentrations of petroleum hydrocarbons and a greater number of individual constituents in the dispersed oil preparations

Do oil dispersants make spilled oil more toxic to fish?

International Nuclear Information System (INIS)

Hodson, P.

2010-01-01

The Deepwater Horizon blowout in the Gulf of Mexico was the world's largest oil spill in terms of duration and volume spilled. Clean-up operations, which involved the continuous and wide-spread use of oil dispersant at the surface and at the seabed discharge point at 1500 metres depth, gave rise to public concern about dispersant toxicity. Reports from the United States Environmental Protection Agency (EPA) claimed little difference in acute toxicity to marine fish and invertebrate species among commonly available dispersants and between dispersed and non-dispersed Louisiana Sweet Crude. Technically, the toxicity of waterborne hydrocarbons does not vary with chemical dispersion. However, the EPA omitted any consideration of loading, and misled the public about the risks of dispersant use in oil clean-up. This study examined the chronic toxicity of dispersed oil to fish embryos. The study revealed that toxicity expressed as oil loading increases by a factor of 10 to 1000 times with dispersion, largely because 10 to 1000 times more oil enters the water column. Since the action of dispersant is on the exposure component of the risk equation, not on the potency of the toxic components of oil, then the risk of oil toxicity to fish increases an equivalent amount.

Biodegradation of dispersed Macondo crude oil by indigenous Gulf of Mexico microbial communities

Energy Technology Data Exchange (ETDEWEB)

Wang, Jian; Sandoval, Kathia; Ding, Yan [Southeaest Environmental Research Center, Florida International University, North Miami Beach, FL 33181 (United States); Stoeckel, Donald; Minard-Smith, Angela [Battelle 505 King Ave, Columbus, OH 43201 (United States); Andersen, Gary; Dubinsky, Eric A. [Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Atlas, Ronald [Department of Biology, University of Louisville, Louisville, KY 40292 (United States); Gardinali, Piero, E-mail: gardinal@fiu.edu [Southeaest Environmental Research Center, Florida International University, North Miami Beach, FL 33181 (United States); Department of Chemistry & Biochemistry, Florida International University, Miami, FL 33199 (United States)

2016-07-01

Because of the extreme conditions of the Deepwater Horizon (DWH) release (turbulent flow at 1500 m depth and 5 °C water temperature) and the sub-surface application of dispersant, small but neutrally buoyant oil droplets < 70 μm were formed, remained in the water column and were subjected to in-situ biodegradation processes. In order to investigate the biodegradation of Macondo oil components during the release, we designed and performed an experiment to evaluate the interactions of the indigenous microbial communities present in the deep waters of the Gulf of Mexico (GOM) with oil droplets of two representative sizes (10 μm and 30 μm median volume diameter) created with Macondo source oil in the presence of Corexit 9500 using natural seawater collected at the depth of 1100–1300 m in the vicinity of the DWH wellhead. The evolution of the oil was followed in the dark and at 5 °C for 64 days by collecting sacrificial water samples at fixed intervals and analyzing them for a wide range of chemical and biological parameters including volatile components, saturated and aromatic hydrocarbons, dispersant markers, dissolved oxygen, nutrients, microbial cell counts and microbial population dynamics. A one phase exponential decay from a plateau model was used to calculate degradation rates and lag times for more than 150 individual oil components. Calculations were normalized to a conserved petroleum biomarker (30αβ-hopane). Half-lives ranged from about 3 days for easily degradable compounds to about 60 days for higher molecular weight aromatics. Rapid degradation was observed for BTEX, 2–3 ring PAHs, and n-alkanes below n-C23. The results in this experimental study showed good agreement with the n-alkane (n-C13 to n-C26) half-lives (0.6–9.5 days) previously reported for the Deepwater Horizon plume samples and other laboratory studies with chemically dispersed Macondo oil conducted at low temperatures (< 8 °C). The responses of the microbial populations also

Influence of dispersants on trophic transfer of petroleum hydrocarbons in a marine food chain

International Nuclear Information System (INIS)

Wolfe, M. F.; Schwartz, G. J. B.; Singaram, S.; Tjeerdema, R. S.

1997-01-01

Experiments were conducted to determine the impact of dispersing agents on petroleum hydrocarbons (PH) bioavailability and trophic transfer in primary levels of a marine food chain. Uptake, bioaccumulation and metabolic transformation of a model PH, ( 1 4C)naphthalene, were measured and compared with Prudhoe Bay Crude Oil (PBCO) dispersed with Corexit 9527, and undispersed preparations of PBCO. The model food chain consisted of a primary algae producer and a primary rotifer consumer. Results showed that uptake of naphthalene increased significantly in the presence of a dispersant in algae. A significant increase in uptake was also recorded in rotifers via trophic transfer. Trophic transfer played a significant, sometimes even dominant, role in uptake and bioaccumulation. 27 refs., 6 figs

The Deepwater Horizon Oil Spill: Ecogenomics of the Deep-Sea Plume

Science.gov (United States)

Hazen, T. C.

2012-12-01

The explosion on April 20, 2010 at the BP-leased Deepwater Horizon drilling rig in the Gulf of Mexico off the coast of Louisiana, resulted in oil and gas rising to the surface and the oil coming ashore in many parts of the Gulf, it also resulted in the dispersment of an immense oil plume 4,000 feet below the surface of the water. Despite spanning more than 600 feet in the water column and extending more than 10 miles from the wellhead, the dispersed oil plume was gone within weeks after the wellhead was capped - degraded and diluted to undetectable levels. Furthermore, this degradation took place without significant oxygen depletion. Ecogenomics enabled discovery of new and unclassified species of oil-eating bacteria that apparently lives in the deep Gulf where oil seeps are common. Using 16s microarrays, functional gene arrays, clone libraries, lipid analysis and a variety of hydrocarbon and micronutrient analyses we were able to characterize the oil degraders. Metagenomic sequence data was obtained for the deep-water samples using the Illumina platform. In addition, single cells were sorted and sequenced for the some of the most dominant bacteria that were represented in the oil plume; namely uncultivated representatives of Colwellia and Oceanospirillum. In addition, we performed laboratory microcosm experiments using uncontaminated water collected from The Gulf at the depth of the oil plume to which we added oil and COREXIT. These samples were characterized by 454 pyrotag. The results provide information about the key players and processes involved in degradation of oil, with and without COREXIT, in different impacted environments in The Gulf of Mexico. We are also extending these studies to explore dozens of deep sediment samples that were also collected after the oil spill around the wellhead. This data suggests that a great potential for intrinsic bioremediation of oil plumes exists in the deep-sea and other environs in the Gulf of Mexico.

Characteristics of suspensions of Kuwait oil and Corexit 7664 and their short- and long-term effects on Tisbe bulbisetosa (Copepoda: Harpacticoida)

Energy Technology Data Exchange (ETDEWEB)

Dalla Venezia, L; Fossato, V U

1977-01-01

A technique for preparing seawater suspensions of Kuwait oil and Corexit was developed. The resulting hydrocarbon concentrations were analyzed by gas-chromatography and spectrofluorometric methods and the stability of the suspensions with time was determined. It was established that the suspensions have an effective stability from Days 3 to 15 after preparation, since in this period the concentration varies within a relatively narrow range. Adult female Tisbe bulbisetosa appeared to be quite tolerant of this type of hydrocarbon suspension, in short-term experiments, especially considering that the concentrations used in the bioassays were about 200 times higher than those measured in a relatively polluted area of the lagoon of Venice. Long-term effects on number of eggs produced, number of nauplii and hatching success for females of the third and fourth generations, subject to continuous exposure, were negligible compared with controls.

Identifying oil/marine snow associations in mesocosm simulations of the Deepwater Horizon oil spill event using solid-state 13C NMR spectroscopy.

Science.gov (United States)

Hatcher, Patrick G; Obeid, Wassim; Wozniak, Andrew S; Xu, Chen; Zhang, Saijin; Santschi, Peter H; Quigg, Antonietta

2018-01-01

The Deepwater Horizon oil spill stimulated the release of marine snow made up of dead/living plankton/bacteria and their exopolymeric polysaccharide substances (EPS), termed marine oil snow (MOS), promoting rapid removal of oil from the water column into sediments near the well site. Mesocosm simulations showed that Macondo surrogate oil readily associates with the marine snow. Quantitative solid-state 13 C NMR readily distinguishes this oil from naturally formed marine snow and reveals that adding the dispersant Corexit enhances the amount of oil associated with the MOS, thus contributing to rapid removal from the water column. Solvent extraction of MOS removes the oil-derived compounds for analysis by one and two-dimensional GC/MS and evaluation of potential transformations they undergo when associated with the EPS. The results reveal that the oil associated with EPS is subjected to rapid transformation, in a matter of days, presumably by bacteria and fungi associated with EPS. Copyright © 2017 Elsevier Ltd. All rights reserved.

The comparative effects of oil dispersants and oil/dispersant conjugates on germination of the marine macroalga Phyllospora comosa (Fucales: Phaeophyta)

International Nuclear Information System (INIS)

Burridge, T.R.; Shir, M.-A.

1995-01-01

Germination inhibition of the marine macrophyte Phyllospora comosa was utilized as a sub-lethal end-point to assess and compare the effects of four oil dispersants and dispersed diesel fuel and crude oil combinations. Inhibition of germination by the water-soluble fraction of diesel fuel increased following the addition of each of the dispersants; the nominal 48-h EC 50 concentration of diesel fuel declined from 6800 to approximately 400 μl 1 -1 nominal for each dispersed combination. This contrasted with crude oil, where the addition of two dispersants resulted in an enhanced germination rate and an increase in nominal EC 50 concentrations from 130 μl 1 -1 for the undispersed crude to 4000 and 2500 μl 1 -1 . The results indicate that, while germination inhibition of P. comosa may be enhanced by the chemical dispersal of oil response varies with type of both oil and oil dispersant. (author)

Chemical dispersibility testing of fresh and weathered oils

International Nuclear Information System (INIS)

Brandvik, P.J.; Daling, P.S.; Aareskjold, K.

1991-05-01

This activity in the DIspersants on Weathered Oils-project (DIWO) is a continuation and an extended study of the dispersibility study described in DIWO report No. 3. The main objective has been to study the chemical dispersibility of fresh and weathered oils produced or transported in Norwegian waters. Other important aims of this study have been: To correlate the effectiveness results obtained by three different laboratory methods; to determine the relationship between the dispersant effectiveness and the change in the oils' physico-chemical properties due to weathering (topping, photo-oxidation and w/o-emulsification). This study has been performed with 8 different oil types and 12 different weathering degrees of each oil type. The work performed clearly demonstrates that the oil type and especially the weathering properties are essential for the performance of dispersants at sea. 41 figs., 5 tabs., 16 refs

The impact of oil dispersant solvent on performance

International Nuclear Information System (INIS)

Fiocco, R.J.; Lessard, R.R.; Canevari, G.P.; Becker, K.W.; Daling, P.S.

1995-01-01

Modern oil spill dispersant formulations are concentrated blends of surface active agents (surfactants) in a solvent carrier system. The surfactants are effective for lowering the interfacial tension of the oil slick and promoting and stabilizing oil-in-water dispersions. The solvent system has 2 key functions: (1) reduce viscosity of the surfactant blend to allow efficient dispersant application, and (2) promote mixing and diffusion of the surfactant blend into the oil film. A more detailed description than previously given in the literature is proposed to explain the mechanism of chemical dispersion and illustrate how the surfactant is delivered by the solvent to the oil-water interface. Laboratory data are presented which demonstrate the variability in dispersing effectiveness due to different solvent composition, particularly for viscous and emulsified test oils with viscosities up to 20,500 mPa·s. Other advantages of improved solvent components can include reduced evaporative losses during spraying, lower marine toxicity and reduced protective equipment requirements. Through this improved understanding of the role of the solvent, dispersants which are more effective over a wider range of oil types are being developed

Comparative toxicity test of water-accommodated fractions of oils and oil dispersants to marine organisms

International Nuclear Information System (INIS)

1989-01-01

This reference method describes a simple procedure for comparing the toxicity of oil, oil dispersants, and mixtures thereof, to marine animals. It allows the toxicity of different dispersants to be rapidly compared to that of oil, or of a mixture of oil an oil dispersant. It is designed for routine monitoring and screening purposes and is not appropriate as a research method. The physical and chemical properties of oil dispersants create many difficulties in the measurements of their toxicity to marine organisms. Strictly speaking, their toxicity can only be accurately estimated using complex procedures and apparatus. (A relatively simple apparatus for preparing oil/water or oil/water/oil dispersant emulsions is described in Appendix B). Simpler methods can provide useful information, provided their limitations are clearly understood and taken into consideration in the assessment and application of their results. Some of the special considerations relating to the measurement of the toxicity of oil and oil dispersants are described in Appendix A. The Appendix also explains the rationale and limitations of the method described here. 3 refs, 4 figs, 2 tabs

Determination of the anionic surfactant di(ethylhexyl) sodium sulfosuccinate in water samples collected from Gulf of Mexico coastal waters before and after landfall of oil from the Deepwater Horizon oil spill, May to October, 2010

Science.gov (United States)

Gray, James L.; Kanagy, Leslie K.; Furlong, Edward T.; McCoy, Jeff W.; Kanagy, Chris J.

2011-01-01

On April 22, 2010, the explosion on and subsequent sinking of the Deepwater Horizon oil drilling platform resulted in the release of crude oil into the Gulf of Mexico. At least 4.4 million barrels had been released into the Gulf of Mexico through July 15, 2010, 10 to 29 percent of which was chemically dispersed, primarily using two dispersant formulations. Initially, the dispersant Corexit 9527 was used, and when existing stocks of that formulation were exhausted, Corexit 9500 was used. Over 1.8 million gallons of the two dispersants were applied in the first 3 months after the spill. This report presents the development of an analytical method to analyze one of the primary surfactant components of both Corexit formulations, di(ethylhexyl) sodium sulfosuccinate (DOSS), the preliminary results, and the associated quality assurance/quality control (QA/QC) from samples collected from various points on the Gulf Coast between Texas and Florida. Seventy water samples and 8 field QC samples were collected before the predicted landfall of oil (pre-landfall) on the Gulf Coast, and 51 water samples and 10 field QC samples after the oil made landfall (post-landfall). Samples were collected in Teflon(Registered) bottles and stored at -20(degrees)C until analysis. Extraction of whole-water samples used sorption onto a polytetrafluoroethylene (PTFE) filter to isolate DOSS, with subsequent 50 percent methanol/water elution of the combined dissolved and particulate DOSS fractions. High-performance liquid chromatography/tandem mass spectrometry (LC/MS/MS) was used to identify and quantify DOSS by the isotope dilution method, using a custom-synthesized 13C4-DOSS labeled standard. Because of the ubiquitous presence of DOSS in laboratory reagent water, a chromatographic column was installed in the LC/MS/MS between the system pumps and the sample injector that separated this ambient background DOSS contamination from the sample DOSS, minimizing one source of blank contamination

Effects of Three Types of Oil Dispersants on Biodegradation of Dispersed Crude Oil in Water Surrounding Two Persian Gulf Provinces

Directory of Open Access Journals (Sweden)

Azadeh Zolfaghari-Baghbaderani

2012-01-01

Full Text Available Objective. To determine the most effective and biodegradable dispersant of spilled oil in water surrounding two Persian Gulf provinces. Methods. This study compared the effects of three dispersants, Pars 1, Pars 2, and Gamlen OD4000 on removal of oil in two Persian Gulf provinces' water. Overall, 16 stations were selected. Using the Well method, the growth rate of isolated bacteria and fungi was identified. To specify the growth rate of microorganisms and their usage of oil in the presence of the above-mentioned dispersants, as exclusive sources of carbon, the bacteria were grown in culture medium for 28 days at 120 rpm, 30∘C, and their optical density was measured by spectrophotometry. Then, we tested biological oxygen demand (BOD and chemical oxygen demand (COD in microorganisms. Results. The highest growth rate was documented for the growth of microorganisms on either Pars 1 or Pars 2 dispersants or their mixtures with oil. However, the culture having microorganisms grown on Pars 1 had higher BOD and COD than the other two dispersants (9200 and 16800 versus 500 and 960, P<0.05. Mixture of oil and Pars 2 as well as oil and Pars 1 dispersants showed the highest BODs and CODs, respectively. In the Bahregan province, microorganisms grown on Pars 2 had maximum amount of BOD and COD in comparison with Pars 1 and Gamlen dispersants (7100 and 15200 versus 6000 and 10560, P<0.05. Conclusion. Pars 1 and Pars 2 were the most effective dispersants with highest degradability comparing Gamlen. In each region, the most suitable compound for removing oil spill from offshores with least secondary contamination should be investigated.

Effects of Three Types of Oil Dispersants on Biodegradation of Dispersed Crude Oil in Water Surrounding Two Persian Gulf Provinces

International Nuclear Information System (INIS)

Zolfaghari-Baghbaderani, A.; Bijani, S.; Zolfaghari-Baghbaderani, A.; Bijani, S.; Emtyazjoo, M.; Emtyazjoo, M.; Poursafa, P.; Mehrabian, S.; Farkhani, D.; Mirmoghtadaee, P.

2012-01-01

Objective. To determine the most effective and biodegradable dispersant of spilled oil in water surrounding two Persian Gulf provinces. Methods. This study compared the effects of three dispersants, Pars 1, Pars 2, and Gamlen OD4000 on removal of oil in two Persian Gulf provinces' water. Overall, 16 stations were selected. Using the Well method, the growth rate of isolated bacteria and fungi was identified. To specify the growth rate of microorganisms and their usage of oil in the presence of the above-mentioned dispersants, as exclusive sources of carbon, the bacteria were grown in culture medium for 28 days at 120 rpm, 30 C, and their optical density was measured by spectrophotometry. Then, we tested biological oxygen demand (BOD) and chemical oxygen demand (COD) in microorganisms. Results. The highest growth rate was documented for the growth of microorganisms on either Pars 1 or Pars 2 dispersants or their mixtures with oil. However, the culture having microorganisms grown on Pars 1 had higher BOD and COD than the other two dispersants (9200 and 16800 versus 500 and 960, P<0.05). Mixture of oil and Pars 2 as well as oil and Pars 1 dispersants showed the highest BODs and CODs, respectively. In the Bahregan province, microorganisms grown on Pars 2 had maximum amount of BOD and COD in comparison with Pars 1 and Gamlen dispersants (7100 and 15200 versus 6000 and 10560, P<0.05). Conclusion. Pars 1 and Pars 2 were the most effective dispersants with highest degradability comparing Gamlen. In each region, the most suitable compound for removing oil spill from off shores with least secondary contamination should be investigated.

Interactions between zooplankton and crude oil: toxic effects and bioaccumulation of polycyclic aromatic hydrocarbons.

Directory of Open Access Journals (Sweden)

Rodrigo Almeda

Full Text Available We conducted ship-, shore- and laboratory-based crude oil exposure experiments to investigate (1 the effects of crude oil (Louisiana light sweet oil on survival and bioaccumulation of polycyclic aromatic hydrocarbons (PAHs in mesozooplankton communities, (2 the lethal effects of dispersant (Corexit 9500A and dispersant-treated oil on mesozooplankton, (3 the influence of UVB radiation/sunlight exposure on the toxicity of dispersed crude oil to mesozooplankton, and (4 the role of marine protozoans on the sublethal effects of crude oil and in the bioaccumulation of PAHs in the copepod Acartia tonsa. Mortality of mesozooplankton increased with increasing oil concentration following a sigmoid model with a median lethal concentration of 32.4 µl L(-1 in 16 h. At the ratio of dispersant to oil commonly used in the treatment of oil spills (i.e. 1∶20, dispersant (0.25 µl L(-1 and dispersant-treated oil were 2.3 and 3.4 times more toxic, respectively, than crude oil alone (5 µl L(-1 to mesozooplankton. UVB radiation increased the lethal effects of dispersed crude oil in mesozooplankton communities by 35%. We observed selective bioaccumulation of five PAHs, fluoranthene, phenanthrene, pyrene, chrysene and benzo[b]fluoranthene in both mesozooplankton communities and in the copepod A. tonsa. The presence of the protozoan Oxyrrhis marina reduced sublethal effects of oil on A. tonsa and was related to lower accumulations of PAHs in tissues and fecal pellets, suggesting that protozoa may be important in mitigating the harmful effects of crude oil exposure in copepods and the transfer of PAHs to higher trophic levels. Overall, our results indicate that the negative impact of oil spills on mesozooplankton may be increased by the use of chemical dispersant and UV radiation, but attenuated by crude oil-microbial food webs interactions, and that both mesozooplankton and protozoans may play an important role in fate of PAHs in marine environments.

Interactions between Zooplankton and Crude Oil: Toxic Effects and Bioaccumulation of Polycyclic Aromatic Hydrocarbons

Science.gov (United States)

Almeda, Rodrigo; Wambaugh, Zoe; Wang, Zucheng; Hyatt, Cammie; Liu, Zhanfei; Buskey, Edward J.

2013-01-01

We conducted ship-, shore- and laboratory-based crude oil exposure experiments to investigate (1) the effects of crude oil (Louisiana light sweet oil) on survival and bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in mesozooplankton communities, (2) the lethal effects of dispersant (Corexit 9500A) and dispersant-treated oil on mesozooplankton, (3) the influence of UVB radiation/sunlight exposure on the toxicity of dispersed crude oil to mesozooplankton, and (4) the role of marine protozoans on the sublethal effects of crude oil and in the bioaccumulation of PAHs in the copepod Acartia tonsa. Mortality of mesozooplankton increased with increasing oil concentration following a sigmoid model with a median lethal concentration of 32.4 µl L−1 in 16 h. At the ratio of dispersant to oil commonly used in the treatment of oil spills (i.e. 1∶20), dispersant (0.25 µl L−1) and dispersant- treated oil were 2.3 and 3.4 times more toxic, respectively, than crude oil alone (5 µl L−1) to mesozooplankton. UVB radiation increased the lethal effects of dispersed crude oil in mesozooplankton communities by 35%. We observed selective bioaccumulation of five PAHs, fluoranthene, phenanthrene, pyrene, chrysene and benzo[b]fluoranthene in both mesozooplankton communities and in the copepod A. tonsa. The presence of the protozoan Oxyrrhis marina reduced sublethal effects of oil on A. tonsa and was related to lower accumulations of PAHs in tissues and fecal pellets, suggesting that protozoa may be important in mitigating the harmful effects of crude oil exposure in copepods and the transfer of PAHs to higher trophic levels. Overall, our results indicate that the negative impact of oil spills on mesozooplankton may be increased by the use of chemical dispersant and UV radiation, but attenuated by crude oil-microbial food webs interactions, and that both mesozooplankton and protozoans may play an important role in fate of PAHs in marine environments. PMID:23840628

Large Scale Behavior and Droplet Size Distributions in Crude Oil Jets and Plumes

Science.gov (United States)

Katz, Joseph; Murphy, David; Morra, David

2013-11-01

The 2010 Deepwater Horizon blowout introduced several million barrels of crude oil into the Gulf of Mexico. Injected initially as a turbulent jet containing crude oil and gas, the spill caused formation of a subsurface plume stretching for tens of miles. The behavior of such buoyant multiphase plumes depends on several factors, such as the oil droplet and bubble size distributions, current speed, and ambient stratification. While large droplets quickly rise to the surface, fine ones together with entrained seawater form intrusion layers. Many elements of the physics of droplet formation by an immiscible turbulent jet and their resulting size distribution have not been elucidated, but are known to be significantly influenced by the addition of dispersants, which vary the Weber Number by orders of magnitude. We present experimental high speed visualizations of turbulent jets of sweet petroleum crude oil (MC 252) premixed with Corexit 9500A dispersant at various dispersant to oil ratios. Observations were conducted in a 0.9 m × 0.9 m × 2.5 m towing tank, where large-scale behavior of the jet, both stationary and towed at various speeds to simulate cross-flow, have been recorded at high speed. Preliminary data on oil droplet size and spatial distributions were also measured using a videoscope and pulsed light sheet. Sponsored by Gulf of Mexico Research Initiative (GoMRI).

Effects of three types of oil dispersants on biodegradation of dispersed crude oil in water surrounding two Persian gulf provinces.

Science.gov (United States)

Zolfaghari-Baghbaderani, Azadeh; Emtyazjoo, Mozhgan; Poursafa, Parinaz; Mehrabian, Sedigheh; Bijani, Samira; Farkhani, Daryoush; Mirmoghtadaee, Parisa

2012-01-01

To determine the most effective and biodegradable dispersant of spilled oil in water surrounding two Persian Gulf provinces. This study compared the effects of three dispersants, Pars 1, Pars 2, and Gamlen OD4000 on removal of oil in two Persian Gulf provinces' water. Overall, 16 stations were selected. Using the Well method, the growth rate of isolated bacteria and fungi was identified. To specify the growth rate of microorganisms and their usage of oil in the presence of the above-mentioned dispersants, as exclusive sources of carbon, the bacteria were grown in culture medium for 28 days at 120 rpm, 30°C, and their optical density was measured by spectrophotometry. Then, we tested biological oxygen demand (BOD) and chemical oxygen demand (COD) in microorganisms. The highest growth rate was documented for the growth of microorganisms on either Pars 1 or Pars 2 dispersants or their mixtures with oil. However, the culture having microorganisms grown on Pars 1 had higher BOD and COD than the other two dispersants (9200 and 16800 versus 500 and 960, P microorganisms grown on Pars 2 had maximum amount of BOD and COD in comparison with Pars 1 and Gamlen dispersants (7100 and 15200 versus 6000 and 10560, P < 0.05). Pars 1 and Pars 2 were the most effective dispersants with highest degradability comparing Gamlen. In each region, the most suitable compound for removing oil spill from offshores with least secondary contamination should be investigated.

Effects of chemical dispersants on oil-brine interfacial tension and droplet formation

International Nuclear Information System (INIS)

Khelifa, A.; So, L.L.C.

2009-01-01

The dispersion of oil spilled in water is influenced by chemical dispersants via the modification of the interfacial properties of the oil, such as oil-brine interfacial tension (IFT). In this study, the physical properties and dispersion of oil were measured in order to determine the effects of chemical dispersants on IFT and oil viscosity and the effects on oil droplet formation. In theory, the maximum size of oil droplet that forms under turbulent mixing increases with IFT. Therefore, a reduction in IFT reduces the size distribution of oil droplets. This paper presented the results of an ongoing project aimed at providing quantitative understanding the influence that chemical dispersants have on the size distribution of oil droplets and oil dispersion. Findings showed that a valid approach is to separate the direct effects of chemical dispersants on oil properties, specifically oil-brine IFT and the effects of mixing on dispersion of chemically treated oil. Under constant mixing conditions, the reduction of the maximum oil droplet size that overcomes the breakage process is determined by the effects of chemical dispersant on oil properties. This correlates well with the dispersant-to-oil ratio (DOR) up to the critical micelle concentration (CMC). This good agreement can be attributed to the reduction of IFT with DOR. It was concluded that the reduction of IFT with dispersant concentration is an additional signature of oil composition on droplet formation, while mixing energy is an external parameter that is independent of oil properties. 17 refs., 3 tabs., 9 figs

Saving oiled mangroves using a new non-dispersing shoreline cleaner

International Nuclear Information System (INIS)

Teas, H.J.; Lessard, R.R.; Canevari, G.P.; Brown, C.D.; Glenn, R.

1993-01-01

Mangroves are ranked as one of the most sensitive marine environments. If mangroves are oiled and no further action is taken, the probability of mortality to the trees is high. One of the ways that viscous spilled oil can kill mangroves is by covering the breathing ports, called lenticels (red mangroves) and pneumatophores (black mangroves), and asphyxiating them by preventing flow of oxygen from the atmosphere into the roots. Mangroves can also be killed by continuous inundation of their prop roots or pneumatophores for a period of ten days to two weeks, but they can survive lenticel covering by water for a few hours at high tide - so there appears to be some grace period during which lenticels can be nonfunctional and the plant can still survive once lenticel function is restored. This suggests that if oil is removed from the breathing ports during the early days after a spill, the lenticels may be able to restore oxygen delivery to the roots and spare the mangroves. Such oils are poorly removed by the washing of tidal waters or by water sprays alone. So a new shoreline cleaner (Corexit 9580), which was specially developed during the cleanup of the Valdez spill in Alaska, was tested to determine its ability to help loosen the oil so it can be washed away with water. Laboratory experiments using excised prop roots of red mangrove (Rhizophora mangle) were initially conducted to determine the feasibility of the approach. Subsequently experiments were carried out using about a hundred potted red mangroves at a test site in Florida. The prop roots, including the lenticels, were coated with a heavy oil (bunker C). After various periods of time, groups of oiled trees were treated with the shoreline cleaner to loosen and remove the oil deposit and then washed with seawater. The results showed that oiled trees could be saved by cleaning within seven days after oiling, indicating that the grace period after oiling extends for about one week

Dispersed oil disrupts microbial pathways in pelagic food webs.

Science.gov (United States)

Ortmann, Alice C; Anders, Jennifer; Shelton, Naomi; Gong, Limin; Moss, Anthony G; Condon, Robert H

2012-01-01

Most of the studies of microbial processes in response to the Deepwater Horizon oil spill focused on the deep water plume, and not on the surface communities. The effects of the crude oil and the application of dispersants on the coastal microbial food web in the northern Gulf of Mexico have not been well characterized even though these regions support much of the fisheries production in the Gulf. A mesocosm experiment was carried out to determine how the microbial community off the coast of Alabama may have responded to the influx of surface oil and dispersants. While the addition of glucose or oil alone resulted in an increase in the biomass of ciliates, suggesting transfer of carbon to higher trophic levels was likely; a different effect was seen in the presence of dispersant. The addition of dispersant or dispersed oil resulted in an increase in the biomass of heterotrophic prokaryotes, but a significant inhibition of ciliates, suggesting a reduction in grazing and decrease in transfer of carbon to higher trophic levels. Similar patterns were observed in two separate experiments with different starting nutrient regimes and microbial communities suggesting that the addition of dispersant and dispersed oil to the northern Gulf of Mexico waters in 2010 may have reduced the flow of carbon to higher trophic levels, leading to a decrease in the production of zooplankton and fish on the Alabama shelf.

Dispersed oil disrupts microbial pathways in pelagic food webs.

Directory of Open Access Journals (Sweden)

Alice C Ortmann

Full Text Available Most of the studies of microbial processes in response to the Deepwater Horizon oil spill focused on the deep water plume, and not on the surface communities. The effects of the crude oil and the application of dispersants on the coastal microbial food web in the northern Gulf of Mexico have not been well characterized even though these regions support much of the fisheries production in the Gulf. A mesocosm experiment was carried out to determine how the microbial community off the coast of Alabama may have responded to the influx of surface oil and dispersants. While the addition of glucose or oil alone resulted in an increase in the biomass of ciliates, suggesting transfer of carbon to higher trophic levels was likely; a different effect was seen in the presence of dispersant. The addition of dispersant or dispersed oil resulted in an increase in the biomass of heterotrophic prokaryotes, but a significant inhibition of ciliates, suggesting a reduction in grazing and decrease in transfer of carbon to higher trophic levels. Similar patterns were observed in two separate experiments with different starting nutrient regimes and microbial communities suggesting that the addition of dispersant and dispersed oil to the northern Gulf of Mexico waters in 2010 may have reduced the flow of carbon to higher trophic levels, leading to a decrease in the production of zooplankton and fish on the Alabama shelf.

Sensitivity of the deep-sea amphipod Eurythenes gryllus to chemically dispersed oil.

Science.gov (United States)

Olsen, Gro Harlaug; Coquillé, Nathalie; Le Floch, Stephane; Geraudie, Perrine; Dussauze, Matthieu; Lemaire, Philippe; Camus, Lionel

2016-04-01

In the context of an oil spill accident and the following oil spill response, much attention is given to the use of dispersants. Dispersants are used to disperse an oil slick from the sea surface into the water column generating a cloud of dispersed oil droplets. The main consequence is an increasing of the sea water-oil interface which induces an increase of the oil biodegradation. Hence, the use of dispersants can be effective in preventing oiling of sensitive coastal environments. Also, in case of an oil blowout from the seabed, subsea injection of dispersants may offer some benefits compared to containment and recovery of the oil or in situ burning operation at the sea surface. However, biological effects of dispersed oil are poorly understood for deep-sea species. Most effects studies on dispersed oil and also other oil-related compounds have been focusing on more shallow water species. This is the first approach to assess the sensitivity of a macro-benthic deep-sea organism to dispersed oil. This paper describes a toxicity test which was performed on the macro-benthic deep-sea amphipod (Eurythenes gryllus) to determine the concentration causing lethality to 50% of test individuals (LC50) after an exposure to dispersed Brut Arabian Light (BAL) oil. The LC50 (24 h) was 101 and 24 mg L(-1) after 72 h and 12 mg L(-1) at 96 h. Based on EPA scale of toxicity categories to aquatic organisms, an LC50 (96 h) of 12 mg L(-1) indicates that the dispersed oil was slightly to moderately toxic to E. gryllus. As an attempt to compare our results to others, a literature study was performed. Due to limited amount of data available for dispersed oil and amphipods, information on other crustacean species and other oil-related compounds was also collected. Only one study on dispersed oil and amphipods was found, the LC50 value in this study was similar to the LC50 value of E. gryllus in our study. Since toxicity data are important input to risk assessment and net environmental

Research on a dispersing solution for burnt crude oils: Aegean Sea oil spill

International Nuclear Information System (INIS)

Bergueiro, J.R.; Morales, N.; Dominguez, F.

1993-01-01

The oil tanker Aegean Sea spilled oil when it grounded during severe storm conditions near La Coruna, Spain. Much of the oil burned after an explosion was caused by the hull breaking apart. Oil which contaminated several beaches was affected by both combustion and weathering. Experiments were conducted on oil sampled from the beaches to investigate dispersion of the oil using Beep Enersperse 1990 at different shaking speeds. Biodegradation experiments were also conducted in the presence of Beep Enersperse 1990 but with seawater absent. Although emulsification of the burnt and weathered oil was very difficult, good dispersion and biodegradation were obtained. After 42 d in a stirred reactor, biodegradation of the oil reached at least 80%. 3 refs., 3 figs., 4 tabs

Molecular Theory and Simulation of Water-Oil Contacts

Science.gov (United States)

Tan, Liang

. Eventually the dispersant COREXIT 9500 was used predominantly in responding to this accident. The formulation of COREXIT dispersants is somewhat complicated and the various constituents (and their interactions) deserve exhaustive study. Here we focus on sorbitan monooleate (SPAN80), one important component of COREXIT 9500, and we investigate its behavior in oil-water-surfactant systems. Extensive all-atom molecular dynamics calculations on the water-squalane interface for nine different loadings with SPAN80, at T = 300K, are analyzed for the surface tension equation of state, desorption free energy profiles as they depend on loading, and to evaluate escape times for absorbed SPAN80 into the bulk phases. These results suggest that loading only weakly affects accommodation of a SPAN80 molecule by this squalane-water interface. Specifically, the surface tension equation of state is simple from conditions of low loading (high tension) to high loading (lower tension) studied, and the desorption free energy profiles are weakly dependent on loading here. The perpendicular motion of the centroid of the SPAN80 head-group ring is well-described by a diffusional model near the minimum of the desorption free energy profile. Lateral diffusional motion is weakly dependent on loading. Escape times evaluated on the basis of a diffusional model and the desorption free energies are 0.07 s (into the squalane) and 300 h (into the water). The latter value is consistent with irreversible absorption observed by related experimental work.

The removal of fatty acids from edible oil : removal of the dispersed phase of a water-in-oil dispersion by a hydrophilic membrane

NARCIS (Netherlands)

Keurentjes, J.T.F.; Doornbusch, G.I.; Riet, van 't K.

1991-01-01

Fatty acids can be extracted from an oil phase by forming a dispersed phase of saponified fatty acids/water/isopropanol in oil. This dispersion can be separated in the two phases by two membranes of opposite polarity in series. In this study the separation of the water phase from the dispersion by a

Oil spill dispersants. Risk assessment for Swedish waters

International Nuclear Information System (INIS)

Lindgren, C.; Lager, H.; Fejes, J.

2001-12-01

IVL has compiled a list of the international usage of oil spill dispersants and presents the technical limitations with the use of such agents as well as the biological effects of these chemical products. IVL, has also conducted an analysis of the pros and cons to using dispersants against oil spills in waters and has applied this with a risk assessment of chemical methods to combat oil spills in the Kattegat and Skagerrak and the Baltic Sea

Oil Dispersion with Abamectin as Active Ingredient

Directory of Open Access Journals (Sweden)

Slavica Gašić

2011-01-01

Full Text Available Abamectin was developed as an insecticide, nematocide and acaricide for use on a varietyof agricultural and horticultural crops. The products with this active ingredient can befound on the market mostly formulated as emulsifiable concentrate (EC. Usually producersrecommend using the EC formulation of abamectin together with some kind of adjuvants(natural oils to improve efficacy of the active ingredient. To overcome the efficacy problemwe tried to formulate the active ingredient abamectin as oil dispersion (OD. Oil dispersion,preferably based on naturally derived oils could improve pesticide efficacy. This type of pesticideformulation contains oil instead of water as in classical suspension concentrate andtypically has better retention and coverage. In the case of abamectin, in this investigationsoybean oil was used with the mixture of different nonionic emulsifiers. Content of abamecetinin formulation was 1.8 %. The developed formulation was tested for few importantparameters. The obtained physicochemical properties for the above mentioned formulationhave shown that it is stable and could be used in plant protection.

Dispersant effectiveness in the field on fresh oils and emulsions

International Nuclear Information System (INIS)

Lunel, T.; Davies, L.

1996-01-01

A detailed data set on the effectiveness of dispersants on fresh oils and emulsions, was presented. The data set could be used to calibrate laboratory dispersant tests and dispersion models so that oil spill response teams would have accurate information to make decisions regarding remediation processes. AEA Technology developed steady state continuous release experiments to provide a data set with quantitative measures of dispersant effectiveness in the field. The Sea Empress incident was closely monitored in order to compare the quantification obtained through field trials. It was noted that the prediction of the percentage of oil dispersed chemically is not the only indication of whether or not to use a dispersant. The important determinant to consider should be the extent to which the natural dispersion process would be enhanced by dispersant application. 17 refs., 5 tabs., 18 figs

Impact of petrochemicals on the photosynthesis of Halophila ovalis using chlorophyll fluorescence

International Nuclear Information System (INIS)

Ralph, P.J.; Burchett, M.D.

1998-01-01

Laboratory-cultured Halophila ovalis showed tolerance to petrochemical exposure up to 1% (w/v) solution of Bass Strait crude oil, an oil dispersant (Corexit 9527) and a mixture of crude oil and dispersant. Quantum yield, as measured by chlorophyll fluorescence, was the most sensitive measure of the photosynthetic processes affected by petrochemical. The results indicated clearly that chlorophyll fluorescence was effective at monitoring the onset and development of stress and recovery of H. ovalis when exposed to crude oil, dispersant and a mixture of the two compounds. Photosynthetic pigment content generally confirmed the chlorophyll fluorescence response; however, several anomalies occurred. (author)

The Logistics of Oil Spill Dispersant Application. Volume I. Logistics-Related Properties of Oil Spill Dispersants.

Science.gov (United States)

1982-11-01

time of application. Such designs were probably influenced by the ready availabilit " 51 of fire-fighting hoses on ships and tugs; the water stream not...8217 I I1 ---- i . . .. . IIII . . . I I PREFACE The use of chemicals for the dispersal of oil spilled on water has been the subject of discussion (and of...20 Oil Type, Weathering and Emulsification.. 20 Slick Thickness .......................... 28 Water Temperature

Optimisation of Oil Spill Dispersants on Weathered Oils. A New Approach Using Experimental Design and Multivariate Data Analysis

Energy Technology Data Exchange (ETDEWEB)

Brandvik, Per Johan

1997-12-31

This thesis describes how laboratory experiments combined with numerical modelling were used to predict weathering of an oil slick at different environmental conditions (temperature, wind etc.). It also applies laboratory test methods to screen dispersant effectiveness under different temperatures and salinities. A new approach is developed for dispersant optimization based on statistical design and multivariate analysis; this resulted in a new dispersant with low toxicity and high effectiveness on a broad selection of oil types. The thesis illustrates the potential of dispersant used as an operational response method on oil spills by discussing three different oil spill scenarios and compares the effect of using dispersants to using mechanical recovery and to doing nothing. Some recommendations that may increase the effectiveness of the Norwegian oil spill contingency are also given. 172 refs., 65 figs., 9 tabs.

Fate of dispersed marine fuel oil in sediment under pre-spill application strategy

International Nuclear Information System (INIS)

Jian Hua

2004-01-01

A comparison of the movement of dispersed oil in marine sediment under two dispersant application scenarios, applied prior to and after oil being spilled overboard, was examined. The pre-spill application scenario caused much less oil to be retained in the top sediment than post-spill scenario. The difference in oil retention in the top sediment between pre- and post-spill application scenario increased with increase in fuel oil temperature. For fuel oil above 40 o C, the difference in the effect of pre-spill application strategy under various water temperatures was negligible. When soap water was used as replacement for chemical dispersant, almost one-half as much oil was retained in the top sediment as that when using chemical dispersant. The adsorption of dispersed oil to the top sediment was almost proportionally decreased with doubling of soap dosage. (Author)

The oil-dispersion bath in anthroposophic medicine--an integrative review.

Science.gov (United States)

Büssing, Arndt; Cysarz, Dirk; Edelhäuser, Friedrich; Bornhöft, Gudrun; Matthiessen, Peter F; Ostermann, Thomas

2008-12-04

Anthroposophic medicine offers a variety of treatments, among others the oil-dispersion bath, developed in the 1930s by Werner Junge. Based on the phenomenon that oil and water do not mix and on recommendations of Rudolf Steiner, Junge developed a vortex mechanism which churns water and essential oils into a fine mist. The oil-covered droplets empty into a tub, where the patient immerses for 15-30 minutes. We review the current literature on oil-dispersion baths. The following databases were searched: Medline, Pubmed, Embase, AMED and CAMbase. The search terms were 'oil-dispersion bath' and 'oil bath', and their translations in German and French. An Internet search was also performed using Google Scholar, adding the search terms 'study' and 'case report' to the search terms above. Finally, we asked several experts for gray literature not listed in the above-mentioned databases. We included only articles which met the criterion of a clinical study or case report, and excluded theoretical contributions. Among several articles found in books, journals and other publications, we identified 1 prospective clinical study, 3 experimental studies (enrolling healthy individuals), 5 case reports, and 3 field-reports. In almost all cases, the studies described beneficial effects - although the methodological quality of most studies was weak. Main indications were internal/metabolic diseases and psychiatric/neurological disorders. Beyond the obvious beneficial effects of warm bathes on the subjective well-being, it remains to be clarified what the unique contribution of the distinct essential oils dispersed in the water can be. There is a lack of clinical studies exploring the efficacy of oil-dispersion baths. Such studies are recommended for the future.

How much crude oil can zooplankton ingest? Estimating the quantity of dispersed crude oil defecated by planktonic copepods

International Nuclear Information System (INIS)

Almeda, Rodrigo; Connelly, Tara L.; Buskey, Edward J.

2016-01-01

We investigated and quantified defecation rates of crude oil by 3 species of marine planktonic copepods (Temora turbinata, Acartia tonsa, and Parvocalanus crassirostris) and a natural copepod assemblage after exposure to mechanically or chemically dispersed crude oil. Between 88 and 100% of the analyzed fecal pellets from three species of copepods and a natural copepod assemblage exposed for 48 h to physically or chemically dispersed light crude oil contained crude oil droplets. Crude oil droplets inside fecal pellets were smaller (median diameter: 2.4–3.5 μm) than droplets in the physically and chemically dispersed oil emulsions (median diameter: 6.6 and 8.0 μm, respectively). This suggests that copepods can reject large crude oil droplets or that crude oil droplets are broken into smaller oil droplets before or during ingestion. Depending on the species and experimental treatments, crude oil defecation rates ranged from 5.3 to 245 ng-oil copepod"−"1 d"−"1, which represent a mean weight-specific defecation rate of 0.026 μg-oil μg-C_c_o_p_e_p_o_d"1 d"−"1. Considering a dispersed crude oil concentration commonly found in the water column after oil spills (1 μl L"−"1) and copepod abundances in high productive coastal areas, copepods may defecate ∼1.3–2.6 mg-oil m"−"3 d"−"1, which would represent ∼0.15%–0.30% of the total dispersed oil per day. Our results indicate that ingestion and subsequent defecation of crude oil by planktonic copepods has a small influence on the overall mass of oil spills in the short term, but may be quantitatively important in the flux of oil from surface water to sediments and in the transfer of low-solubility, toxic petroleum hydrocarbons into food webs after crude oil spills in the sea. - Highlights: • Copepods exposed to dispersed crude oil produced fecal pellets contained numerous small oil droplets (2.4 to 3.5 µm). • Copepods could reject large oil droplets or oil droplets are broken into

Enhancing crude oil degradation in a sandy soil: Effects of addition ...

African Journals Online (AJOL)

This study investigated the effects of the addition of poultry manure alone and in combination with surfactant (Goldcrew or Corexit) and/or alternate carbon substrate (glucose or starch) on crude oil degradation in a sandy soil. With poultry manure alone, optimal crude oil degradation was obtained at a concentration of 4.0% ...

The Deep-Sea Microbial Community from the Amazonian Basin Associated with Oil Degradation.

Science.gov (United States)

Campeão, Mariana E; Reis, Luciana; Leomil, Luciana; de Oliveira, Louisi; Otsuki, Koko; Gardinali, Piero; Pelz, Oliver; Valle, Rogerio; Thompson, Fabiano L; Thompson, Cristiane C

2017-01-01

One consequence of oil production is the possibility of unplanned accidental oil spills; therefore, it is important to evaluate the potential of indigenous microorganisms (both prokaryotes and eukaryotes) from different oceanic basins to degrade oil. The aim of this study was to characterize the microbial response during the biodegradation process of Brazilian crude oil, both with and without the addition of the dispersant Corexit 9500, using deep-sea water samples from the Amazon equatorial margin basins, Foz do Amazonas and Barreirinhas, in the dark and at low temperatures (4°C). We collected deep-sea samples in the field (about 2570 m below the sea surface), transported the samples back to the laboratory under controlled environmental conditions (5°C in the dark) and subsequently performed two laboratory biodegradation experiments that used metagenomics supported by classical microbiological methods and chemical analysis to elucidate both taxonomic and functional microbial diversity. We also analyzed several physical-chemical and biological parameters related to oil biodegradation. The concomitant depletion of dissolved oxygen levels, oil droplet density characteristic to oil biodegradation, and BTEX concentration with an increase in microbial counts revealed that oil can be degraded by the autochthonous deep-sea microbial communities. Indigenous bacteria (e.g., Alteromonadaceae, Colwelliaceae , and Alcanivoracaceae ), archaea (e.g., Halobacteriaceae, Desulfurococcaceae , and Methanobacteriaceae ), and eukaryotic microbes (e.g., Microsporidia, Ascomycota, and Basidiomycota) from the Amazonian margin deep-sea water were involved in biodegradation of Brazilian crude oil within less than 48-days in both treatments, with and without dispersant, possibly transforming oil into microbial biomass that may fuel the marine food web.

Regulatory policies for using oil dispersants in the Barents Sea

Directory of Open Access Journals (Sweden)

Natalia Belkina

2015-04-01

Full Text Available Use of dispersants requires assessment of which environmental values are at stake. In the Barents Sea this issue is of high concern as large oil spills can cause transboundary pollution, affecting the interests of two neighbouring countries. The Joint Contingency Plan in the Barents Sea does not set any specific requirements for use of dispersants and lets Norway and Russia follow their national procedures. The Plan emphasizes that in case of transboundary pollution the decision to use dispersants shall only be undertaken upon common agreement. The paper presents a comparison of the national regulatory approaches of Norway and Russia to using dispersants. The research is based on the analysis of legislative documents and interviews with oil companies, oil spill responders and relevant national authorities. The research reveals that in both countries use of dispersants requires preliminary authorization of the national agencies. In Norway the pre-approval procedure and the algorithm of dispersants involvement in response to a real accident are clearly documented and are regularly tested. This has made the process of approval for using dispersants more efficient. In Russia the lack of practical experience in using dispersants and well-established approval procedures can result in a long and unclear permitting process for each oil spill case. This could seriously hinder the use of dispersants to combat transboundary pollution in the Barents Sea, even if it is considered to be beneficial. We conclude that the development of a harmonized approach for dispersants use in the Barents Sea should be thoroughly assessed.

Concentrations of viable oil-degrading microorganisms are increased in feces from Calanus finmarchicus feeding in petroleum oil dispersions.

Science.gov (United States)

Størdal, Ingvild Fladvad; Olsen, Anders Johny; Jenssen, Bjørn Munro; Netzer, Roman; Hansen, Bjørn Henrik; Altin, Dag; Brakstad, Odd Gunnar

2015-09-15

Zooplankton are suggested to be biotic contributors to the transport and weathering of oil in marine environments due to their ingestion of oil. In the present experiment, feeding activity and microbial communities in feces from Calanus finmarchicus feeding in oil dispersions were characterized. Feeding activity was significantly reduced in oil dispersions. The microbial communities in clean and oil-containing copepod feces were dominated by Rhodobacteraceae family bacteria (Lesingera, Phaeobacter, Rugeria, and Sulfitobacter), which were suggested to be indigenous to copepod feces. The results also indicated that these bacteria were metabolizing oil compounds, as a significant increase in the concentrations of viable oil degrading microorganisms was observed in oil-containing feces. This study shows that bacteria in feces from copepods feeding in dilute oil dispersions have capacity for degradation of oil. Zooplankton may therefore contribute to weathering of oil by excreting feces with microbial communities already adapted to degradation of oil. Copyright © 2015 Elsevier Ltd. All rights reserved.

Anomalous dispersion of magnetic spiky particles for enhanced oil emulsions/water separation.

Science.gov (United States)

Chen, Hui-Jiuan; Hang, Tian; Yang, Chengduan; Liu, Guishi; Lin, Di-An; Wu, Jiangming; Pan, Shuolin; Yang, Bo-Ru; Tao, Jun; Xie, Xi

2018-01-25

In situ effective separation of oil pollutants including oil spills and oil emulsions from water is an emerging technology yet remains challenging. Hydrophobic micro- or nano-materials with ferromagnetism have been explored for oil removal, yet the separation efficiency of an oil emulsion was compromised due to the limited dispersion of hydrophobic materials in water. A surfactant coating on microparticles prevented particle aggregation, but reduced oil absorption and emulsion cleaning ability. Recently, polystyrene microbeads covered with nanospikes have been reported to display anomalous dispersion in phobic media without surfactants. Inspired by this phenomenon, here magnetic microparticles attached with nanospikes were fabricated for enhanced separation of oil emulsions from water. In this design, the particle surfaces were functionalized to be superhydrophobic/superoleophilic for oil absorption, while the surface of the nanospikes prevented particle aggregation in water without compromising surface hydrophobicity. The magnetic spiky particles effectively absorbed oil spills on the water surface, and readily dispersed in water and offered facile cleaning of the oil emulsion. In contrast, hydrophobic microparticles without nanospikes aggregated in water limiting the particle-oil contact, while surfactant coating severely reduced particle hydrophobicity and oil absorption ability. Our work provides a unique application scope for the anomalous dispersity of microparticles and their potential opportunities in effective oil-water separation.

Influence of physical and chemical dispersion on the biodegradation of oil under simulated marine conditions

International Nuclear Information System (INIS)

Swannell, R. P. J.; Daniel, F.; Croft, B. C.; Engelhardt, M. A.; Wilson, S.; Mitchell, D. J.; Lunel, T.

1997-01-01

Dispersion and biodegradation of oil was studied in marine microcosms designed to simulate oil dispersion at sea. Dispersion was studied using both Phase Doppler Particle Analyser and a Chamber Slide technique. In both natural and artificial seawater, oil addition was observed to encourage the growth of hydrocarbon-degrading bacteria in the presence of sufficient nitrogen and phosphorus. Results showed that microorganisms enhanced oil dispersion by colonizing physically-dispersed oil droplets and preventing re-coalescence with the surface slick. The addition of dispersants increased the rate of colonization as well as the number of degraded droplets. These results suggest that stimulation of physical dispersion by chemical means increase the rate of oil biodegradation under natural conditions. 25 refs., 3 tabs., 14 figs

Acute toxicities of crude oils and oil-dispersant mixtures to Red sea fishes and invertebrates

Energy Technology Data Exchange (ETDEWEB)

Eisler, R.

1975-11-01

Crude oil from fields in the Persian Gulf and in the Sinai plus a chemical oil dispersant were tested, using static bioassay procedures, for toxicity to adults or juveniles of ten marine species: Heteroxenia fuscescens, a soft coral; Nerita forskali and Drupa granulata, gastropod molluscs; Mytilus variabilis, a mussel; Acanthopleura haddoni, a chiton (mollusc); Echinometra mathaei, sea urchin; Calcinus latens, a hermit crab; Palaemon pacificus, a shrimp; Parupeneus barberinus, goatfish; and Siganus rivulatus, rabbitfish. Concentrations fatal to 50 percent of individual test species in 168 hours, LC-50 (168 h), ranged from 0.74 to more than 30.0 ml/liter for Persian Gulf crude, from 14.5 to more than 30.0 ml/liter for Sinai crude, and from 0.006 to 0.064 ml/liter for the dispersant. In general, fishes and crustaceans were the most sensitive groups assayed and molluscs the most resistant. LC-50 (168 h) values for oil-dispersant mixtures of 10 parts oil to 1 part dispersant (v/v) for selected species ranged from 0.047 to 0.152 ml/liter which appears to reflect the biocidal properties of the dispersant. Some individuals that survived immersion in high concentrations of the test compounds for 168 h were adversely affected during treatment and afterwards.

The Deep-Sea Microbial Community from the Amazonian Basin Associated with Oil Degradation

Directory of Open Access Journals (Sweden)

Mariana E. Campeão

2017-06-01

Full Text Available One consequence of oil production is the possibility of unplanned accidental oil spills; therefore, it is important to evaluate the potential of indigenous microorganisms (both prokaryotes and eukaryotes from different oceanic basins to degrade oil. The aim of this study was to characterize the microbial response during the biodegradation process of Brazilian crude oil, both with and without the addition of the dispersant Corexit 9500, using deep-sea water samples from the Amazon equatorial margin basins, Foz do Amazonas and Barreirinhas, in the dark and at low temperatures (4°C. We collected deep-sea samples in the field (about 2570 m below the sea surface, transported the samples back to the laboratory under controlled environmental conditions (5°C in the dark and subsequently performed two laboratory biodegradation experiments that used metagenomics supported by classical microbiological methods and chemical analysis to elucidate both taxonomic and functional microbial diversity. We also analyzed several physical–chemical and biological parameters related to oil biodegradation. The concomitant depletion of dissolved oxygen levels, oil droplet density characteristic to oil biodegradation, and BTEX concentration with an increase in microbial counts revealed that oil can be degraded by the autochthonous deep-sea microbial communities. Indigenous bacteria (e.g., Alteromonadaceae, Colwelliaceae, and Alcanivoracaceae, archaea (e.g., Halobacteriaceae, Desulfurococcaceae, and Methanobacteriaceae, and eukaryotic microbes (e.g., Microsporidia, Ascomycota, and Basidiomycota from the Amazonian margin deep-sea water were involved in biodegradation of Brazilian crude oil within less than 48-days in both treatments, with and without dispersant, possibly transforming oil into microbial biomass that may fuel the marine food web.

Assessment of the use of dispersants on oil spills in California marine waters

International Nuclear Information System (INIS)

Trudel, K.; Ross, S.; Belore, R.; Buffington, S.; Ogawa, C.; Panzer, D.

2002-01-01

The technical issues regarding the use of dispersants to clean up oil spills from offshore production sources and transportation sources in California were assessed in this study which examined both operational and environmental issues. The operational issues included the dispersibility of produced and imported oils, along with the capabilities of California response resources to deal with typical spills and limiting environmental impacts to offshore environments. The environmental issues include the risks associated with typical spills and potential net environmental benefit of chemically dispersing oil spills. Most crude oils produced offshore California are heavy and border on the undispersable range, but the imported crudes are somewhat lighter. Modeling has shown that most produced oils and some imported oils emulsify quickly and weather more quickly to the point where they are no longer dispersible. There is a very narrow window of time for chemical dispersions to be used effectively. The net environmental benefit analysis demonstrates that the use of dispersants lessens the total environmental impact of spill scenarios. It was emphasized that it is necessary to act quickly if chemical dispersion is to be effective. Rapid response strategies are needed, including locally based vessel and helicopter spraying systems. 19 refs., 8 tabs., 1 fig

The oil-dispersion bath in anthroposophic medicine – an integrative review

Science.gov (United States)

Büssing, Arndt; Cysarz, Dirk; Edelhäuser, Friedrich; Bornhöft, Gudrun; Matthiessen, Peter F; Ostermann, Thomas

2008-01-01

Background Anthroposophic medicine offers a variety of treatments, among others the oil-dispersion bath, developed in the 1930s by Werner Junge. Based on the phenomenon that oil and water do not mix and on recommendations of Rudolf Steiner, Junge developed a vortex mechanism which churns water and essential oils into a fine mist. The oil-covered droplets empty into a tub, where the patient immerses for 15–30 minutes. We review the current literature on oil-dispersion baths. Methods The following databases were searched: Medline, Pubmed, Embase, AMED and CAMbase. The search terms were 'oil-dispersion bath' and 'oil bath', and their translations in German and French. An Internet search was also performed using Google Scholar, adding the search terms 'study' and 'case report' to the search terms above. Finally, we asked several experts for gray literature not listed in the above-mentioned databases. We included only articles which met the criterion of a clinical study or case report, and excluded theoretical contributions. Results Among several articles found in books, journals and other publications, we identified 1 prospective clinical study, 3 experimental studies (enrolling healthy individuals), 5 case reports, and 3 field-reports. In almost all cases, the studies described beneficial effects – although the methodological quality of most studies was weak. Main indications were internal/metabolic diseases and psychiatric/neurological disorders. Conclusion Beyond the obvious beneficial effects of warm bathes on the subjective well-being, it remains to be clarified what the unique contribution of the distinct essential oils dispersed in the water can be. There is a lack of clinical studies exploring the efficacy of oil-dispersion baths. Such studies are recommended for the future. PMID:19055811

The oil-dispersion bath in anthroposophic medicine – an integrative review

Directory of Open Access Journals (Sweden)

Bornhöft Gudrun

2008-12-01

Full Text Available Abstract Background Anthroposophic medicine offers a variety of treatments, among others the oil-dispersion bath, developed in the 1930s by Werner Junge. Based on the phenomenon that oil and water do not mix and on recommendations of Rudolf Steiner, Junge developed a vortex mechanism which churns water and essential oils into a fine mist. The oil-covered droplets empty into a tub, where the patient immerses for 15–30 minutes. We review the current literature on oil-dispersion baths. Methods The following databases were searched: Medline, Pubmed, Embase, AMED and CAMbase. The search terms were 'oil-dispersion bath' and 'oil bath', and their translations in German and French. An Internet search was also performed using Google Scholar, adding the search terms 'study' and 'case report' to the search terms above. Finally, we asked several experts for gray literature not listed in the above-mentioned databases. We included only articles which met the criterion of a clinical study or case report, and excluded theoretical contributions. Results Among several articles found in books, journals and other publications, we identified 1 prospective clinical study, 3 experimental studies (enrolling healthy individuals, 5 case reports, and 3 field-reports. In almost all cases, the studies described beneficial effects – although the methodological quality of most studies was weak. Main indications were internal/metabolic diseases and psychiatric/neurological disorders. Conclusion Beyond the obvious beneficial effects of warm bathes on the subjective well-being, it remains to be clarified what the unique contribution of the distinct essential oils dispersed in the water can be. There is a lack of clinical studies exploring the efficacy of oil-dispersion baths. Such studies are recommended for the future.

A laboratory approach for determining the effect of oils and dispersants on mangroves

Energy Technology Data Exchange (ETDEWEB)

Baca, B.J.

1982-10-01

An experimental approach was developed and applied to testing the effects of oil and dispersant combinations on the growth of mangrove seedlings (trees of the intertidal tropics). A controlled growth chamber was employed to test the effects of different oils and dispersed oils in an array of dosages applied to different parts of the plants. Preliminary test results are reported for two species of mangroves collected from five localities, including both oiled and unoiled estuaries. Differences occurred between species, substances, dosages, the part of the plant dosed, and the presence of chronic oil pollution at localities from which the stocks were collected. Avicennia germinans (L.) L. (black mangrove) was more sensitive than Rhizophora mangle L. (red mangrove) when exposed to almost all substances tested. Light Arabian crude oil (LA) and light Arabian crude oil dispersed (LAD) were the most toxic substances tested. No. 2 fuel oil (N2) and No. 2 fuel oil dispersed (N2D) were as toxic as LA and LAD, except for an increase (an enhancement effect) in foliage and stem growth in Avicennia at lower dosages. Bunker C oil (BC) was the least toxic of the oils tested, resulting in the reduction of foliage and stem growth only at the highest dosage tested in Avicennia. Bunker C oil dispersed (BCD) failed to show effects in either species at any dosage tested. The leaves of Rhizophora were the most sensitive part of the plant tested.

Oil Spills and Dispersants Can Cause the Initiation of Potentially Harmful Dinoflagellate Blooms ("Red Tides").

Science.gov (United States)

Almeda, Rodrigo; Cosgrove, Sarah; Buskey, Edward J

2018-04-25

After oil spills and dispersant applications the formation of red tides or harmful algal blooms (HABs) has been observed, which can cause additional negative impacts in areas affected by oil spills. However, the link between oil spills and HABs is still unknown. Here, we present experimental evidence that demonstrates a connection between oil spills and HABs. We determined the effects of oil, dispersant-treated oil, and dispersant alone on the structure of natural plankton assemblages in the Northern Gulf of Mexico. In coastal waters, large tintinnids and oligotrich ciliates, major grazers of phytoplankton, were negatively affected by the exposure to oil and dispersant, whereas bloom-forming dinoflagellates ( Prorocentrum texanum, P. triestinum, and Scrippsiella trochoidea) notably increased their concentration. The removal of key grazers due to oil and dispersant disrupts the predator-prey controls ("top-down controls") that normally function in plankton food webs. This disruption of grazing pressure opens a "loophole" that allows certain dinoflagellates with higher tolerance to oil and dispersants than their grazers to grow and form blooms when there are no growth limiting factors (e.g., nutrients). Therefore, oil spills and dispersants can act as disrupters of predator-prey controls in plankton food webs and as indirect inducers of potentially harmful dinoflagellate blooms.

Determination of uptake of dispersed oil in the copepod Calanus finmarchicus

International Nuclear Information System (INIS)

Melbye, A.G.; Altin, D.; Frost, T.

2001-01-01

Many research programs in Norway have focused on the acute toxic effects of oils on zooplankton. Oil companies and those responsible for pollution control strive to develop predictive models for the fate and behaviour of seawater discharges from offshore activities. The models include transport, acute toxic effects, uptake and biodegradation, and accumulation in the food chain. Exposure studies have been conducted using both static tests and continuous flow tests. This paper presented a study in which the biological uptake of dispersed oil in the copepod Calanus finmarchicus was examined using a specially designed flow-through system with an oil dispersion generator. The oil used in the exposure studies was a base oil product from TotalFina that had a very low concentration of water-soluble components, and had very low acute toxicity towards the test organism. The oil was dispersed to a size range of 1 to 10μm. The test species actively filters water for particles in the size range less than 10 to 50 μm. Exposure of the oil dispersion at an average concentration of 600 μg/L gave increasing bioaccumulation from 7 to 14 days, and the calculated bioaccumulation factor was found to be in the range of 200-800. Solvent washing of a duplicate sample of zooplankton at 14 days indicated that a significant portion of the hydrocarbon is absorbed to the surface of the organisms. 14 refs., 4 tabs., 5 figs

Fate of dispersants associated with the deepwater horizon oil spill.

Science.gov (United States)

Kujawinski, Elizabeth B; Kido Soule, Melissa C; Valentine, David L; Boysen, Angela K; Longnecker, Krista; Redmond, Molly C

2011-02-15

Response actions to the Deepwater Horizon oil spill included the injection of ∼771,000 gallons (2,900,000 L) of chemical dispersant into the flow of oil near the seafloor. Prior to this incident, no deepwater applications of dispersant had been conducted, and thus no data exist on the environmental fate of dispersants in deepwater. We used ultrahigh resolution mass spectrometry and liquid chromatography with tandem mass spectrometry (LC/MS/MS) to identify and quantify one key ingredient of the dispersant, the anionic surfactant DOSS (dioctyl sodium sulfosuccinate), in the Gulf of Mexico deepwater during active flow and again after flow had ceased. Here we show that DOSS was sequestered in deepwater hydrocarbon plumes at 1000-1200 m water depth and did not intermingle with surface dispersant applications. Further, its concentration distribution was consistent with conservative transport and dilution at depth and it persisted up to 300 km from the well, 64 days after deepwater dispersant applications ceased. We conclude that DOSS was selectively associated with the oil and gas phases in the deepwater plume, yet underwent negligible, or slow, rates of biodegradation in the affected waters. These results provide important constraints on accurate modeling of the deepwater plume and critical geochemical contexts for future toxicological studies.

A laboratory study of particulate and gaseous emissions from crude oil and crude oil-dispersant contaminated seawater due to breaking waves

Science.gov (United States)

Afshar-Mohajer, Nima; Li, Cheng; Rule, Ana M.; Katz, Joseph; Koehler, Kirsten

2018-04-01

Crude oil spill incidents occur frequently causing a verity of occupational, ecological and environmental problems. Dispersants are applied to enhance the dispersion rate of crude oil slicks into the water column. In this study, the aerosol size distribution from 10 nm to 20 μm, total particle-bound aromatic hydrocarbons (pPAH) and volatile organic compounds (VOCs) are measured in a 6 x 0.3 x 0.6 m tank as plunging breaking waves entrain oil slicks. The experiments are performed for seawater with slicks of crude oil, crude oil-dispersant mixture and dispersant only. The measurements investigate the effects of wave energy and slick properties on the temporal evolution of the emissions. The total number concentrations of particles originating from the oil-dispersant mixture are 1-2 orders of magnitude higher than those of crude oil across the entire nano-scale range, reaching 100x for 20 nm particles. Conversely, the differences in concentration are small in the micron range. The average concentrations of pPAH are variable but similar (150-270 ng/m3). The VOC concentrations for crude oil-dispersant mixtures are 2-3 times lower than those of crude oil, presumably due to the surfactant effect on mass diffusion. The drastic increase in ultrafine particle concentrations may raise concerns about effects of inhalation by cleanup workers and downstream communities though VOC emissions reduce. Findings through this study provide insight into how the spray of dispersant may change the ratio of airborne particulate matter and VOC emissions from seawater due to natural processes.

Biodegradation and photooxidation of crude oil under natural sunlight in the northern Gulf of Mexico

Science.gov (United States)

Bacosa, H. P.; Erdner, D.; Liu, Z.

2016-02-01

An enormous amount of oil was observed in the deep and surface waters of the northern Gulf of Mexico (nGoM) following the Deepwater Horizon (DWH) spill. While the oil degradation and bacterial communities in the deep-sea plume have been widely investigated, the effect of sunlight on oil and bacterial assemblages in surface waters have received less attention. In this study, we amended surface water collected near the DWH site with crude oil and/or Corexit dispersant and incubated under natural sunlight in the nGoM for 36 d in summer of 2013. The residual alkanes, polycyclic aromatic hydrocarbons (PAHs), and alkalyted PAHs were analyzed by GC-MS, and bacterial community was determined via pyrosequencing. The results show that n-alkane biodegradation rate constants (first order) were ca. ten-fold higher than the photooxidation rate constants. While biodegradation was characterized by a lag phase, photooxidation rate constants for the 2-3 ring and 4-5 ring PAHs, were 0.08-0.98 day-1 and 0.01-0.07 day-1, respectively. Compared to biodegradation, photooxidation increased the transformation of 4-5 ring PAHs by 70% and 3-4 ring alkylated PAHs by 36%. Sunlight significantly reduced bacterial diversity and a driver of shifts in bacterial community structure in oil and Corexit treatments. In amended treatments, sunlight increased the relative abundances of Alteromonas, Marinobacter, Labrenzia, Sandarakinotalea, Halomonas and Bartonella, while the dark treatments enriched Thalassobius, Winogradskyella, Alcanivorax, Formosa, Eubacterium, Erythrobacter, Natronocella, and Pseudomonas. This suggests that different bacteria are degrading the hydrocarbons in the dark and under light exposure. In a follow up study using DNA-Stable isotope probing (SIP), we identified the alkane and PAH degraders using 13C-labeled hexadecane and phenanthrene, respectively. The results of metagenomic and metatranscriptomic analyses in the light and dark incubations will be presented. For the first

Electrochemical masstransfer of oil hydrocarbons in dispersed soils

Energy Technology Data Exchange (ETDEWEB)

Nekrasova, M.A.; Zvolinsky, V.P.; Kanev, M.V. [Russian Friendship Peoples Univ., Dept. of Eecological Monitoring and Forecasting, Moscow (Russian Federation)

2001-07-01

A large-scale pollution of the geological environment is a result of imperfect processes of mining, refining, haul of oil and irrational use of petroleum. The processes of masstransfer of hydrocarbons in dispersed soils and the problems of forming of a dual electric layer (DEL) on the demarcations 'water-oil' and 'mineral-water' are still insufficiently studied. Therefore, one of the most important problems in the field of the ecological geology is the analysis of ways of cleaning of soils from hydrocarbons. The kaolinitic clay from the Tirlianskoye deposit (K{sub 2}, st. Jabik, Bashkiria) and average polymineral loam (prlllkl, Moscow region, the south-east of town Zvenigorod) was chosen as the objects of the experimental study. The mixture of West Siberian oils was used for model pollution. The experimental laboratory researches of electrochemical migration of hydrocarbons were carried out on dispersiblis clayey soils. (orig.)

Oil Spills and Dispersants Can Cause the Initiation of Potentially Harmful Dinoflagellate Blooms ("Red Tides")

DEFF Research Database (Denmark)

Almeda, Rodrigo; Cosgrove, Sarah; Buskey, Edward J.

2018-01-01

After oil spills and dispersant applications the formation of red tides or harmful algal blooms (HABs) has been observed, which can cause additional negative impacts in areas affected by oil spills. However, the link between oil spills and HABs is still unknown. Here, we present experimental...... evidence that demonstrates a connection between oil spills and HABs. We determined the effects of oil, dispersant-treated oil, and dispersant alone on the structure of natural plankton assemblages in the Northern Gulf of Mexico. In coastal waters, large tintinnids and oligotrich ciliates, major grazers...

Chemically dispersed oil is cytotoxic and genotoxic to sperm whale skin cells.

Science.gov (United States)

Wise, Catherine F; Wise, James T F; Wise, Sandra S; Wise, John Pierce

2018-06-01

Two major oil crises in United States history, the 1989 Exxon-Valdez oil spill in Alaska and the 2010 Deepwater Horizon Oil Rig explosion in the Gulf of Mexico, drew attention to the need for toxicological experiments on oil and chemically dispersed oil. We are still learning the effects these spills had on wildlife. However, little data is known about the toxicity of these substances in marine mammals. The objective of this study is to determine the toxicity of Alaskan oil, as well as chemically dispersed oil. Oil experiments were performed using the water accommodated fraction of Alaskan oil (WAF) and the chemically enhanced water accommodated fraction of Alaskan oil (CEWAF). The Alaskan WAF is not cytotoxic to sperm whale skin cells though it did induce chromosome damage; S9-mediated metabolism did not affect the cytotoxicity of WAF but did increase the levels of chromosome damage. Alaskan CEWAF is more cytotoxic and genotoxic than the WAF; S9 mediated metabolism increased both cytotoxicity and genotoxicity of CEWAF. Analysis of the PAH content of Alaskan WAF and CEWAF revealed a forty-fold increase in the total levels of PAHs in CEWAF compared to WAF. These findings show that chemically dispersed oil leads to higher levels of PAH exposure which are more toxic and likely to lead to longer and more persistent health effects. Copyright © 2017 Elsevier Inc. All rights reserved.

Coalescence kinetics of dispersed crude oil in a laboratory reactor

International Nuclear Information System (INIS)

Sterling, M.C. Jr.; Ojo, T.; Autenrieth, R.L.; Bonner, J.S.; Page, C.A.; Ernst, A.N.S.

2002-01-01

A study was conducted to examine the effects of salinity and mixing energy on the resurfacing and coalescence rates of chemically dispersed crude oil droplets. This kinetic study involved the use of mean shear rates to characterize the mixing energy in a laboratory reactor. Coagulation kinetics of dispersed crude oil were determined within a range of mean shear rates of 5, 10, 15, and 20 per second, and with salinity values of 10 and 30 per cent. Observed droplet distributions were fit to a transport-reaction model to estimate collision efficiency values and their dependence on salinity and mixing energy. Dispersant efficiencies were compared with those derived from other laboratory testing methods. Experimentally determined dispersant efficiencies were found to be 10 to 50 per cent lower than predicted using a non-interacting droplet model, but dispersant efficiencies were higher than those predicted using other testing methods. 24 refs., 1 tab., 3 figs

Stress response of the black coral Leiopathes glaberrima when exposed to sub-lethal amounts of crude oil and dispersant

Directory of Open Access Journals (Sweden)

Dannise V. Ruiz-Ramos

2017-12-01

Full Text Available The 2010 Deep Water Horizon oil well failure released billions of gallons of crude oil into the deep Gulf of Mexico, and, combined with chemical dispersants, this oil caused significant coral mortality. However, the mechanisms by which oil and dispersed oil impact deep marine fauna are not well understood. Here, we investigate the effects of oil and dispersed oil on a black coral common in the deep Gulf of Mexico, 'Leiopathes glaberrima. 'This coral occurs in several color morphs that show ecological and genetic differences. We hypothesized that dispersed oil would be more detrimental to coral health than oil alone and that this difference would be detectable in the gene expression response of the colonies even at sub-lethal concentrations. In two experiments, four and six colonies of red and white color morphs were exposed to oil, dispersant, and dispersed oil for a minimum of 96 hours. Visual assessment indicated that indeed dispersant and dispersed oil treatments were more damaging than oil alone, for target concentrations of 25 mg L–1. Decline in health was observed for all treatments, independently of color morphotype, but the decline was faster in the white colonies exposed to dispersant. The responses to the treatments were also investigated by monitoring gene expression after 24 hours of sub-lethal chemical exposure. Coral gene expression differed by chemical stressor. Interestingly, the polycyclic aromatic hydrocarbon biomarker gene, cytochrome P450, was only up-regulated in dispersed oil but not oil alone, suggesting that the dispersant increased the availability of such hydrocarbons in the tissue. The gene expression response was apparent at 24 hours when visual impacts were not (yet detectable. The use of chemical dispersants in oil-spill remediation may cause health declines in deep-water corals and deserves further study.

The influence of diffusion and dispersion on heavy oil recovery by VAPEX

Energy Technology Data Exchange (ETDEWEB)

Alkindi, A. [Imperial College, London (United Kingdom); Muggeridge, A. [Society of Petroleum Engineers, London (United Kingdom)]|[Imperial College, London (United Kingdom); Al-Wahaibi, Y. [Society of Petroleum Engineers, Dubai (United Arab Emirates)]|[Sultan Qaboos Univ., Muscat (Oman)

2008-10-15

Heavy oil recovery using vapour extraction (VAPEX) is a promising improved oil recovery technique. However, field application of this process has been limited due to concerns that favourable laboratory recoveries may not scale up to the field level. Previous laboratory studies of VAPEX in porous media have obtained much higher production rates than predicted either by analytic models derived from Hele-Shaw experiments or numerical simulation. The difference between experimental and simulation models has been explained by assuming greater mixing between vapour and oil than would be expected from molecular diffusion. Convective dispersion is a plausible justification for this increase. This paper investigated the role of convective dispersion on oil recovery by VAPEX using a combination of well characterized laboratory experiments and numerical simulation. So that all mechanisms contributing to increased-mixing apart from convective dispersion were eliminated, a first contact miscible fluid system was used. Longitudinal and transverse dispersion coefficients were experimentally measured as a function of flow-rate and viscosity ratio. VAPEX drainage experiments were then conducted over a range of injection rates. The paper also discussed the comparison of laboratory measurements of oil drainage rates with those predicted by the Butler-Mokrys analytical model and numerical simulation using either molecular diffusion or convective dispersion. Last, the paper discussed the use of the numerical model in investigating the impact of rate, well separation, and reservoir geometry on recovery. 21 refs., 4 tabs., 12 figs.

Exposure to Crude Oil and Chemical Dispersant May Impact Marine Microbial Biofilm Composition and Steel Corrosion

Directory of Open Access Journals (Sweden)

Jennifer L. Salerno

2018-06-01

Full Text Available The release of hydrocarbons and chemical dispersant in marine environments may disrupt benthic ecosystems, including artificial reefs, formed by historic steel shipwrecks, and their associated organisms. Experiments were performed to determine the impacts of crude oil, dispersed crude oil, and dispersant on the community structure and function of microorganisms in seawater (SW and biofilms formed on carbon steel, a common ship hull construction material. Steel corrosion was also monitored to illustrate how oil spills may impact preservation of steel shipwrecks. Microcosms were filled with seawater (SW and incubated at 4°C. Carbon steel disks (CSDs were placed in each tank, and tanks were amended with crude oil and/or dispersant or no treatment. SW and CSD biofilms were sampled biweekly for genetic analysis using Illumina sequencing of 16S ribosomal RNA gene amplicons. Predicted and sequenced bacterial metagenomes were analyzed to examine impacts of oil and dispersant on metabolic function. Gammaproteobacteria, Alphaproteobacteria, and Flavobacteriia dominated SW and biofilms. Bacterial community structure differed significantly between treatments for SW and biofilms. OTUs affiliated with known (Pseudomonas and potential (Marinomonas hydrocarbon-degraders were roughly twice as abundant in biofilms treated with oil and dispersed oil, and steel corrosion of CSDs in these treatments was higher compared to control and dispersant treatments. OTUs affiliated with the Rhodobacteraceae family (biofilm formers and potential oil degraders were less abundant in the dispersant treatment compared to other treatments in biofilm and SW samples, but OTUs affiliated with the Pseudoalteromonas genus (biofilm formers and proposed hydrocarbon degraders were more abundant in dispersant-treated biofilms. Overall, functional gene analyses revealed a decrease in genes (predicted using PICRUSt and observed in sequenced metagenomes associated with hydrocarbon degradation

Gulf of Mexico Air Quality: CALIPSO Support for Gulf of Mexico Air Quality Relating to the Deepwater Horizon Oil Spill

Science.gov (United States)

Nguyen, Myngoc T.; Lapointe, Stephen; Jennings, Brittney; Zoumplis, Angela

2011-01-01

On April 20, 2010, an oil platform belonging to BP exploded and leaked a huge volume of oil into the Gulf of Mexico. In an effort to control the spread of the oil, BP applied dispersants such as Corexit and conducted in-situ burnings of the oil. This catastrophe created a complex chain of events that affected not only the fragile water and land ecosystems, but the humans who breathe the air every day. Thousands of people were exposed to fumes associated with oil vapors from the spill, burning of the oil, and the toxic mixture of dispersants. While aiding in clean-up efforts, local fishermen were directly exposure to fumes when working on the Gulf. A notable amount of Gulf Coast residents were also exposed to the oil fumes as seasonal southeasterly winds blew vapors toward land. The Volatile Organic Compounds (VOC) found in oil vapors include: benzene, toluene, ethyl benzene, xylene, naphthalene, hydrogen sulfide and particulate matter (PM). Increases in water temperature and sunlight due to the summer season allow for these VOCs and PM to evaporate into the air more rapidly. Aside from the VOCs found in oil vapors, the dispersant being used to break up the oil is highly toxic and is thought to be even more toxic than the oil itself (EPA website, 2010). To protect human health, the environment, and to make informed policy decisions relevant to the spill, the EPA Region 6 has continuously monitored the affected areas carefully for levels of pollutants in the outdoor air that are associated with petroleum products and the burning of oil along the coast. In an effort to prevent, prepare for, and respond to future oil spills that occur in and around inland waters of the United States, the EPA has been working with local, state, and federal response partners. Air quality measurements were collected by the EPA at five active monitoring systems stationed along the coast.

Incorporating different vegetable oils into an aqueous dispersion of hybrid organic nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Samyn, Pieter, E-mail: Pieter.Samyn@fobawi.uni-freiburg.de [Albert-Luedwigs-University Freiburg, Institute for Forest Utilization (Germany); Schoukens, Gustaaf [Ghent University, Department of Textiles (Belgium); Stanssens, Dirk; Vonck, Leo; Van den Abbeele, Henk [Topchim N.V. (Belgium)

2012-08-15

Different vegetable oils including soy oil, high-oleic sunflower oil, corn oil, castor oil (CO), rapeseed oil, and hydrogenated CO were added to the imidization reaction of poly(styrene-maleic anhydride) or SMA, with ammonium hydroxide in aqueous medium. The oils favorably reduce viscosity during ammonolysis of the anhydride moieties and increase the maximum solid content of the dispersed imidized SMA to at least 50 wt%, compared to a maximum of 35 wt% for pure imidized SMA. The viscosity of imidized SMA with polyunsaturated oils was generally larger than for monosaturated oils, but it was highest for COs due to high contents of hydroxyl groups. Depending on the oil reactivity, homogeneous or core-shell nanoparticles with 20-60 nm diameters formed. The interactions of oil and organic phase were studied by Fourier-transform infrared spectroscopy, indicating qualitative variances between different oils, the fraction imidized SMA and remaining fraction of ammonolyzed SMA without leakage of oil upon diluting the dispersion and precipitation at low pH. A quantitative analysis with calculation of imide contents, amounts of reacted oil and chemical interactions was made by Fourier-transform-Raman spectroscopy suggesting that most interactions take place around the unsaturated oil moieties and ammonolyzed anhydride.

Biotransformation of petroleum hydrocarbons and microbial communities in seawater with oil dispersions and copepod feces.

Science.gov (United States)

Størdal, Ingvild Fladvad; Olsen, Anders Johny; Jenssen, Bjørn Munro; Netzer, Roman; Altin, Dag; Brakstad, Odd Gunnar

2015-12-30

To determine biotransformation of components in crude oil dispersions in the presence of feces from marine copepods, dispersed oil was incubated alone, with the addition of clean or oil-containing feces. We hypothesized that the feces would contribute with nutrients to bacteria, and higher concentrations of oil-degrading bacteria, respectively. Presence of clean feces resulted in higher degradation of aromatic oil compounds, but lower degradation of n-alkanes. Presence of oil-containing feces resulted in higher degradation of n-alkanes. The effect of clean feces on aromatic compounds are suggested to be due to higher concentrations of nutrients in the seawater where aromatic degradation takes place, while the lower degradation of n-alkanes are suggested to be due to a preference by bacteria for feces over these compounds. Large aggregates were observed in oil dispersions with clean feces, which may cause sedimentation of un-weathered lipophilic oil compounds towards the seafloor if formed during oil spills. Copyright © 2015 Elsevier Ltd. All rights reserved.

In-situ production of biosurfactants: An alternative method for dispersing and bioremediating marine oil spills

International Nuclear Information System (INIS)

Josefsen, K.; Sveum, P.; Ramstad, S.; Markussen, S.; Folkvord, K.; Krigsvoll, S.; Aune, R.; Storroe, I.

1995-01-01

A study of surfactant producing bacteria for the dispersion of oil spills was conducted. Isolation procedures, shoreline experiments, flume basin experiments, and simulated open sea meso-scale experiments and results were described. Bacteria strains were obtained from several locations world-wide, though more success was experienced with strains from colder regions. Two strains were used in the meso-scale experiment. A rapid reduction in the aliphatic fraction of the dispersed oil was observed. Most strains were found to be capable of dispersing crude oils with differing compositions. Efforts to emulsify oil-in-water on an artificial shoreline with biosurfactants producing bacteria showed only limited success in mobilizing the oil. 8 figs., 2 tabs., 14 refs

Dispersed oil decreases the ability of a model fish (Dicentrarchus labrax) to cope with hydrostatic pressure.

Science.gov (United States)

Dussauze, Matthieu; Pichavant-Rafini, Karine; Belhomme, Marc; Buzzacott, Peter; Privat, Killian; Le Floch, Stéphane; Lemaire, Philippe; Theron, Michaël

2017-01-01

Data on the biological impact of oil dispersion in deep-sea environment are scarce. Hence, the aim of this study was to evaluate the potential interest of a pressure challenge as a new experimental approach for the assessment of consequences of chemically dispersed oil, followed by a high hydrostatic pressure challenge. This work was conducted on a model fish: juvenile Dicentrarchus labrax. Seabass were exposed for 48 h to dispersant alone (nominal concentration (NC) = 4 mg L -1 ), mechanically dispersed oil (NC = 80 mg L -1 ), two chemically dispersed types of oil (NC = 50 and 80 mg L -1 with a dispersant/oil ratio of 1/20), or kept in clean seawater. Fish were then exposed for 30 min at a simulated depth of 1350 m, corresponding to pressure of 136 absolute atmospheres (ATA). The probability of fish exhibiting normal activity after the pressure challenge significantly increased from 0.40 to 0.55 when they were exposed to the dispersant but decreased to 0.26 and 0.11 in the case of chemical dispersion of oil (at 50 and 80 mg L -1 , respectively). The chemical dispersion at 80 mg L -1 also induced an increase in probability of death after the pressure challenge (from 0.08 to 0.26). This study clearly demonstrates the ability of a pressure challenge test to give evidence of the effects of a contaminant on the capacity of fish to face hydrostatic pressure. It opens new perspectives on the analysis of the biological impact of chemical dispersion of oil at depth, especially on marine species performing vertical migrations.

Relative toxicity of oil dispersants to Mytilus viridis and Macrobrachium idella

Digital Repository Service at National Institute of Oceanography (India)

DeSilva, C.; Row, A.

) was almost identical for both the species tested, although there was a significant shift in the range of LC sub(50) values, indicating that one species is less sensitive than the other. Oil dispersant mixtures were less toxic than the dispersants alone...

Bioaccumulation and subacute toxicity of mechanically and chemically dispersed heavy fuel oil in sea urchin (Glyptocidaris crenulari

Directory of Open Access Journals (Sweden)

Bailin Yang

2015-12-01

Full Text Available Oil spills have a disastrous ecological impact on ecosystems but few data are available for the effects of dispersed oil on benthic marine organisms. In order to provide information for assessment, we analysed the hydrocarbon compositions of the mechanically dispersed water accommodated fraction (MDWAF and the chemically dispersed water accommodated fraction (CDWAF of No. 120 fuel oil, their bioaccumulation, and DNA damage related to oil exposure, using the sea urchin as a sentinel organism. The results show that the concentration of polycyclic aromatic hydrocarbon in the tissues of sea urchin exposed to the CDWAF is higher than that of those exposed to the MDWAF. The single cell gel electrophoresis assay results also indicated higher DNA damage from exposure to the CDWAF of oil. Thus, dispersants should be applied with caution in oil spill accidents.

How much crude oil can zooplankton ingest? Estimating the quantity of dispersed crude oil defecated by planktonic copepods

DEFF Research Database (Denmark)

Almeda, Rodrigo; Connelly, Tara L.; Buskey, Edward J.

2016-01-01

% of the analyzed fecal pellets from three species of copepods and a natural copepod assemblage exposed for 48 h to physically or chemically dispersed light crude oil contained crude oil droplets. Crude oil droplets inside fecal pellets were smaller (median diameter: 2.4-3.5 mu m) than droplets in the physically...

Changes in cardiac activity, oxygen uptake and perfusion indices in Carcinus maenas (L. ) exposed to crude oil and dispersant

Energy Technology Data Exchange (ETDEWEB)

Depledge, M.H.

1984-01-01

Cardiac activity and oxygen consumption increased when C. maenas were exposed to a 20% solution of the water-soluble fraction of Fortes crude oil, a 10% solution of the dispersant BP1100WD or a combination of both. Normal feeding behaviour was disrupted. Perfusion indices (Q/VO2) decreased as locomotor activity increased following exposure to crude oil. However, exposure to dispersant or dispersant + crude oil resulted in elevation of perfusion index despite crabs becoming active. All test animals survived for at least 6 weeks following exposure to the pollutants. The acute, sublethal effects of dispersant and dispersant + crude oil were more severe than the effects of crude oil alone.

Hsp60-induced tolerance in the rotifer Brachionus plicatilis exposed to multiple environmental contaminants.

Science.gov (United States)

Wheelock, C E; Wolfe, M F; Olsen, H; Tjeerdema, R S; Sowby, M L

1999-04-01

Hsp60 induction was selected as a sublethal endpoint of toxicity for Brachionus plicatilis exposed to a water accommodated fraction (WAF) of Prudhoe Bay crude oil (PBCO), a PBCO/dispersant (Corexit 9527(R)) fraction and Corexit 9527(R) alone. To examine the effect of multiple stressors, exposures modeled San Francisco Bay, where copper levels are approximately 5 microgram/L, salinity is 22 per thousand, significant oil transport and refining occurs, and petroleum releases have occurred historically. Rotifers were exposed to copper at 5 microgram/L for 24 h, followed by one of the oil/dispersant preparations for 24 h. Batch-cultured rotifers were used in this study to model wild populations instead of cysts. SDS-PAGE with Western Blotting using hsp60-specific antibodies and chemiluminescent detection were used to isolate, identify, and measure induced hsp60 as a percentage of control values. Both PBCO/dispersant and dispersant alone preparations induced significant levels of hsp60. However, hsp60 expression was reduced to that of controls at high WAF concentrations, suggesting interference with protein synthesis. Rotifers that had been preexposed to copper maintained elevated levels of hsp60 upon treatment with WAF at all concentrations. Results suggest that induction of hsp60 by chronic low-level exposure may serve as a protective mechanism against subsequent or multiple stressors and that hsp60 levels are not additive for the toxicants tested in this study, giving no dose-response relationship. The methods employed in this study could be useful for quantifying hsp60 levels in wild rotifer populations.

The case for using vessel-based systems to apply oil-spill dispersants

International Nuclear Information System (INIS)

Ross, S.

1998-01-01

Most emergency plans for dealing with marine oil spills include the use of chemical dispersants. This paper presents a comparison between the capabilities of aircraft-based dispersant application systems and vessel-based systems. The comparison was presented in terms of the logistics of treating offshore spills. Vessel-based systems have certain advantages in terms of their availability and cost. They have better spray control and accuracy and can dose thick slicks in one pass. However, this advantage is lost if the dispersant payload on the vessel is relatively small and the spill is located very far from the base of operations. Under certain conditions, vessel-based dispersant application systems can treat spills as quickly as aircraft-based systems. Most marine spills tend to occur in restricted waters near ports where dispersant stockpiles could be stored for ready use by vessels in the area. Development of a modern vessel-based, fire-monitor system for applying chemical dispersant onto marine oil spills was one of the recommendations emerging from the study. 32 refs., 6 tabs., 1 fig

In situ production of bio-surfactants: An alternative method for dispersing and bioremediating marine oil spills

International Nuclear Information System (INIS)

Josefsen, K.D.; Sveum, P.; Ramstad, P.; Markussen, S.; Folkvord, K.; Krigsvoll, K.; Aune, R.; Storroe, I.

1995-01-01

Some oil degrading bacteria are able to produce surfactants. These biosurfactants enhance dispersion of oil droplets into the water column. A large number of surfactant producing bacterial strains have been isolated from seawater samples collected at different sites around the world. Strains isolated from seawater samples collected in cold regions generally had better properties than strains isolated from warm seawater. Many of the isolated strains were able to disperse crude oils with a large variation of composition, as well as the water-in-emulsion (chocolate mousse) formed during weathering of crude oil in the sea. The results show that in situ application of surfactant producing bacteria can be a viable tool in future oil spill contingency, and that dispersion of oil may increase the biodegradation rate. Work is in progress to examine the use of such bacteria in the bioremediation of oil contaminated shorelines. 10 refs., 3 figs., 2 tabs

Combined effects of Corexit EC 9500A with secondary abiotic and biotic factors in the rotifer Brachionus plicatilis.

Science.gov (United States)

Williams, Michael B; Powell, Mickie L; Watts, Stephen A

2016-10-01

We examined lethality and behavioral effects of Corexit EC 9500A (C-9500A) exposure on the model marine zooplankton Brachionus plicatilis singularly and in combination with abiotic and biotic factors. C-9500A exposure at standard husbandry conditions (17.5ppt, 24°C, 200 rotifer*mL(-1) density) identified the 24h median lethal concentration, by Probit analysis, to be 107ppm for cultured B. plicatilis. Rotifers surviving exposure to higher concentrations (100 and 150ppm) exhibited a decreased swimming velocity and a reduced net to gross movement ratio. Significant interaction between C-9500A exposure and temperature or salinity was observed. Upper thermal range was reduced and maximal salinity stress was seen as ca. 25ppt. Increased or decreased nutritional availability over the exposure period did not significantly alter mortality of B. plicatilis populations at the concentrations tested. Results from this study may be useful for predicting possible outcomes on marine zooplankton following dispersant application under diverse natural conditions. Copyright © 2016 Elsevier Inc. All rights reserved.

In-Situ Microprobe Observations of Dispersed Oil with Low-Temperature Low-Vacuum Scanning Electron Microscope

International Nuclear Information System (INIS)

Mohsen, H.T.

2010-01-01

A low cost cryostat stage from high heat capacity material is designed and constructed, in attempt to apply size distribution techniques for examination of oil dispersions. Different materials were tested according to their heat capacity to keep the liquid under investigation in frozen state as long as possible during the introduction of the cryostat stage to the low-vacuum scanning electron microscope. Different concentrations of non ionic surfactant were added to artificially contaminated with 10000 ppm Balayeam base oil in 3.5 % saline water, where oil and dispersing liquid have been added and shacked well to be investigated under the microscope as fine frozen droplets. The efficiency of dispersion was examined using low temperature low-vacuum scanning electron microscope. The shape and size distributions of freeze oil droplets were studied by digital imaging processing technique in conjunction with scanning electron microscope counting method. Also elemental concentration of oil droplets was analyzed.

Weathering of hydrocarbons in mangrove sediments: testing the effects of using dispersants to treat oil spills

International Nuclear Information System (INIS)

Burns, K.A.; Codi, S.; Pratt, C.; Duke, N.C.

1999-01-01

This field study was a combined chemical and biological investigation of the relative effects of using dispersants to treat oil spills impacting mangrove habitats. The aim of the chemistry was to determine whether dispersant affected the short- or long-term composition of a medium range crude oil (Gippsland) stranded in a tropical mangrove environment in Queensland, Australia. Sediment cores from three replicate plots of each treatment (oil only and oil plus dispersant) were analyzed for total hydrocarbons and for individual molecular markers (alkanes, aromatics, triterpanes, and steranes). Sediments were collected at 2 days, then 1, 7, 13 and 22 months post-spill. Over this time, oil in the six treated plots decreased exponentially from 36.6 ± 16.5 to 1.2 ± 0.8 mg/g dry wt. There was no statistical difference in initial oil concentrations, penetration of oil to depth, or in the rates of oil dissipation between oiled or dispersed oil plots. At 13 months, alkanes were > 50% degraded, aromatics were ∼30% degraded based upon ratios of labile to resistant markers. However, there was no change in the triterpane or sterane biomarker signatures of the retained oil. This is of general forensic interest for pollution events. The predominant removal processes were evaporation (≤27%) and dissolution (≥56%), with a lag-phase of 1 month before the start of significant microbial degradation (≤17%). The most resistant fraction of the oil that remained after 7 months (the higher molecular weight hydrocarbons) correlated with the initial total organic carbon content of the soil. Removal rate in the Queensland mangroves was significantly faster than that observed in the Caribbean and was related to tidal flushing. (author)

Effects of oil dispersant on solubilization, sorption and desorption of polycyclic aromatic hydrocarbons in sediment–seawater systems

International Nuclear Information System (INIS)

Zhao, Xiao; Gong, Yanyan; O’Reilly, S.E.; Zhao, Dongye

2015-01-01

Highlights: • Oil dispersant enhances solubilization of PAHs more effectively than surfactants. • Dispersant and dispersed oil enhance sediment sorption of PAHs and induce hysteresis. • Partitioning to sediment-sorbed dispersant is the mechanism for enhanced PAH uptake. • Dual-mode models well simulate dispersant-facilitated sorption of PAHs on sediment. • Deepwater conditions reduce solubilization of PAHs and lessen dispersant effects. - Abstract: This work investigated effects of a prototype oil dispersant on solubilization, sorption and desorption of three model PAHs in sediment–seawater systems. Increasing dispersant dosage linearly enhanced solubility for all PAHs. Conversely, the dispersant enhanced the sediment uptake of the PAHs, and induced significant desorption hysteresis. Such contrasting effects (adsolubilization vs. solubilization) of dispersant were found dependent of the dispersant concentration and PAH hydrophobicity. The dual-mode models adequately simulated the sorption kinetics and isotherms, and quantified dispersant-enhanced PAH uptake. Sorption of naphthalene and 1-methylnaphthalene by sediment positively correlated with uptake of the dispersant, while sorption of pyrene dropped sharply when the dispersant exceeded its critical micelle concentration (CMC). The deepwater conditions diminished the dispersant effects on solubilization, but enhanced uptake of the PAHs, albeit sorption of the dispersant was lowered. The information may aid in understanding roles of dispersants on distribution, fate and transport of petroleum PAHs in marine systems

Behavioural response of pink salmon Fry Oncorhynchus gorbuscha to fresh, weathered, and dispersed crude oil

International Nuclear Information System (INIS)

Moles, A.

2009-01-01

Very little is known about fish behaviour in relation to oil spill contamination. In this study, out-migrant pink salmon fry Oncorhynchus gorbuscha were subjected to varying concentrations of oil and sea water solutions, or uncontaminated sea water at a temperature of 7 degrees C. Fresh oil, artificially weathered oil, and dispersed oil samples were used. Twenty trials were run for concentrations of 48 aromatic and 30alkane hydrocarbons. The number of minutes spent in the uncontaminated water was significantly higher than sample areas. Fry avoided water-accommodated mixtures of Alaska North Slope crude oil in sea water at concentrations of 960 mg/L total aromatic hydrocarbon fresh oil and 873 mg/L total aromatic hydrocarbon dispersed oil. Concentrations corresponded to 75 per cent and 68 per cent of the median lethal concentration level. However, the fry did not avoid the weathered oil, which indicated that the fry may be sensitive to monoaromatic hydrocarbon components in the oil. It was concluded that oil pollution may alter pink salmon migration behaviour. 28 refs., 1 tab., 2 figs

Self-dispersed crumpled graphene balls in oil for friction and wear reduction.

Science.gov (United States)

Dou, Xuan; Koltonow, Andrew R; He, Xingliang; Jang, Hee Dong; Wang, Qian; Chung, Yip-Wah; Huang, Jiaxing

2016-02-09

Ultrafine particles are often used as lubricant additives because they are capable of entering tribological contacts to reduce friction and protect surfaces from wear. They tend to be more stable than molecular additives under high thermal and mechanical stresses during rubbing. It is highly desirable for these particles to remain well dispersed in oil without relying on molecular ligands. Borrowing from the analogy that pieces of paper that are crumpled do not readily stick to each other (unlike flat sheets), we expect that ultrafine particles resembling miniaturized crumpled paper balls should self-disperse in oil and could act like nanoscale ball bearings to reduce friction and wear. Here we report the use of crumpled graphene balls as a high-performance additive that can significantly improve the lubrication properties of polyalphaolefin base oil. The tribological performance of crumpled graphene balls is only weakly dependent on their concentration in oil and readily exceeds that of other carbon additives such as graphite, reduced graphene oxide, and carbon black. Notably, polyalphaolefin base oil with only 0.01-0.1 wt % of crumpled graphene balls outperforms a fully formulated commercial lubricant in terms of friction and wear reduction.

Dispersed catalysts for transforming extra heavy crude oil into transportable upgraded crude: phase identification

Energy Technology Data Exchange (ETDEWEB)

Martinez, S.; Canizales, E.; Machin, I. [Gerencia Depttal de Investigacion Estrategica en Refinacion PDVSA Intevep (Venezuela); Segovia, X.; Rivas, A.; Lopez, E.; Pena, J.P.; Rojas, J.D.; Sardella, R. [Gerencia Depttal de Infraestructura y Mejoramiento en Faja Petrolifera PDVSA Intevep (Venezuela)

2011-07-01

A new technology to convert extra heavy crude oil into transportable upgraded crude has been developed. A water/oil emulsion composed of steam and catalyst precursors is introduced in the feed which then generates unsupported dispersed catalyst in situ under thermal decomposition. The aim of this paper is to characterize the particles. The study was conducted in a laboratory and on a pilot scale on three different vacuum residues using high resolution transmission electron microscopy and a transmission electron microscope. Results showed that the particles were formed by oxides and inorganic sulphur based in transition metals and their sizes ranged between 5 and 120 nm; in addition, good dispersion was observed. This study demonstrated that the process involved in the generation of dispersed catalyst is extremely complex and showed that further work with heavy crude oils and its residua is required to understand the mechanisms involved.

Effect of dispersants on the growth of indigenous bacterial population and biodegradation of crude oil

Digital Repository Service at National Institute of Oceanography (India)

Bhosle, N.B.; Row, A.

Oil dispersants (5 from Castrol Ltd., Bombay and 2 from British Petroleum, London) were studied individually and in combination with Saudi Arabian crude oil for their effect on the growth of indigenous bacteria and on the biodegradation of oil. None...

Size Distribution and Dispersion of Droplets Generated by Impingement of Breaking Waves on Oil Slicks

Science.gov (United States)

Li, C.; Miller, J.; Wang, J.; Koley, S. S.; Katz, J.

2017-10-01

This laboratory experimental study investigates the temporal evolution of the size distribution of subsurface oil droplets generated as breaking waves entrain oil slicks. The measurements are performed for varying wave energy, as well as large variations in oil viscosity and oil-water interfacial tension, the latter achieved by premixing the oil with dispersant. In situ measurements using digital inline holography at two magnifications are applied for measuring the droplet sizes and Particle Image Velocimetry (PIV) for determining the temporal evolution of turbulence after wave breaking. All early (2-10 s) size distributions have two distinct size ranges with different slopes. For low dispersant to oil ratios (DOR), the transition between them could be predicted based on a turbulent Weber (We) number in the 2-4 range, suggesting that turbulence plays an important role. For smaller droplets, all the number size distributions have power of about -2.1, and for larger droplets, the power decreases well below -3. The measured steepening of the size distribution over time is predicted by a simple model involving buoyant rise and turbulence dispersion. Conversely, for DOR 1:100 and 1:25 oils, the diameter of slope transition decreases from ˜1 mm to 46 and 14 µm, respectively, much faster than the We-based prediction, and the size distribution steepens with increasing DOR. Furthermore, the concentration of micron-sized droplets of DOR 1:25 oil increases for the first 10 min after entrainment. These phenomena are presumably caused by the observed formation and breakup oil microthreads associated with tip streaming.

Evolution of the Macondo well blowout: simulating the effects of the circulation and synthetic dispersants on the subsea oil transport.

Science.gov (United States)

Paris, Claire B; Hénaff, Matthieu Le; Aman, Zachary M; Subramaniam, Ajit; Helgers, Judith; Wang, Dong-Ping; Kourafalou, Vassiliki H; Srinivasan, Ashwanth

2012-12-18

During the Deepwater Horizon incident, crude oil flowed into the Gulf of Mexico from 1522 m underwater. In an effort to prevent the oil from rising to the surface, synthetic dispersants were applied at the wellhead. However, uncertainties in the formation of oil droplets and difficulties in measuring their size in the water column, complicated further assessment of the potential effect of the dispersant on the subsea-to-surface oil partition. We adapted a coupled hydrodynamic and stochastic buoyant particle-tracking model to the transport and fate of hydrocarbon fractions and simulated the far-field transport of the oil from the intrusion depth. The evaluated model represented a baseline for numerical experiments where we varied the distributions of particle sizes and thus oil mass. The experiments allowed to quantify the relative effects of chemical dispersion, vertical currents, and inertial buoyancy motion on oil rise velocities. We present a plausible model scenario, where some oil is trapped at depth through shear emulsification due to the particular conditions of the Macondo blowout. Assuming effective mixing of the synthetic dispersants at the wellhead, the model indicates that the submerged oil mass is shifted deeper, decreasing only marginally the amount of oil surfacing. In this scenario, the oil rises slowly to the surface or stays immersed. This suggests that other mechanisms may have contributed to the rapid surfacing of oil-gas mixture observed initially. The study also reveals local topographic and hydrodynamic processes that influence the oil transport in eddies and multiple layers. This numerical approach provides novel insights on oil transport mechanisms from deep blowouts and on gauging the subsea use of synthetic dispersant in mitigating coastal damage.

A laboratory dispersant effectiveness test which reflects dispersant efficiency in the field

International Nuclear Information System (INIS)

Lunel, T.; Wood, P.

1996-01-01

Oil dispersion efficiencies of surfactants, from laboratory dispersion tests and field data were compared and calibrated. Data from an oil spill, where dispersants were used as a major part of the response, was analysed. The data was accumulated through the monitoring of the dispersant operation of the Sea Empress spill incident, in which Forties Blend oil was spilled at sea. This detailed data set was used to calibrate existing laboratory dispersant tests, and to devise a new International Dispersant Effectiveness Test. The objective was to create a comprehensive guide to decision making on whether and when to start a dispersant spraying operation. The dispersion efficiencies obtained from the laboratory dispersant tests were compared with field data. Flume tests produced the highest percentage of dispersed oil for all the dispersal tests. However, it was emphasised that the total percentage of oil dispersed should not be the only measure of dispersant effectiveness, since it does not distinguish between the contribution of natural and chemically enhanced dispersion. 9 refs., 1 tab., 9 figs

Evaluation of field-collected data measuring fluorescein dye movements and dispersion for dispersed oil transport modeling

Energy Technology Data Exchange (ETDEWEB)

French McCay, D.; Mueller, C.; Jayko, K.; Longval, B.; Schroeder, M. [Applied Science Associates Inc., Narragansett, RI (United States); Terrill, E.; Carter, M.; Otero, M.; Kim, S.Y. [Scripps Inst. of Oceanography, La Jolla, CA (United States); Nordhausen, W.; Lampinen, M. [California Dept. of Fish and Game, San Diego, CA (United States). Office of Spill Prevention and Response; Payne, J.R. [Payne Environmental Consultants Inc., Encinitas, CA (United States); Ohlmann, C. [California Univ., Santa Barbara, CA (United States)

2007-07-01

In the event of on oil spill at sea, the concentration of hydrocarbons in the water column can be evaluated using oil spill fate and transport modeling. Such modeling can also determine the potential exposure to zooplankton, and the impacts of oil spills with and without the use of dispersants. This paper reported on fluorescein dye studies that were conducted off Sand Diego, California to evaluate the ability of transport models to hindcast movement and dispersion of dye using data such as surface currents calculated from high-frequency radar; near surface currents from drifter measurements drogued at several depths; dye concentrations measured by fluorescence; spreading and dye intensity measurements based on aerial photography; and, water density profiles from conductivity-temperature-depth (CTD) casts. This paper presented modeling issues that remain to be addressed, such as the need to resolve small-scale transport processes in order to evaluate effects on water column biota. Since these processes determining current velocities are complex, it is not feasible to include most of the complexities at appropriately small scales in oil spill modeling applications. The difficulty in predicting currents that transport oil components and organisms with a hydrodynamic model application that does not include temporal details in the forcing function was also discussed. This paper demonstrated that the SIMAP spill trajectory model, using the drifter velocities as current input, successfully reproduced trajectories of the dye. The effect of wind drift transporting the surface material faster than the subsurface materials was identified as a spreading mechanism. Therefore, subtraction of the wind drift from the shallower drifter velocities, and inclusion of wind drift in SIMAP would allow those velocities to be used for depths other than those tracked by the drifters. 57 refs., 8 tabs., 17 figs.

A new perspective of particle adsorption: Dispersed oil and granular materials interactions in simulated coastal environment.

Science.gov (United States)

Meng, Long; Bao, Mutai; Sun, Peiyan

2017-09-15

This study, adsorption behaviors of dispersed oil in seawaters by granular materials were explored in simulation environment. We quantitatively demonstrated the dispersed oil adsorbed by granular materials were both dissolved petroleum hydrocarbons (DPHs) and oil droplets. Furthermore, DPHs were accounted for 42.5%, 63.4%, and 85.2% (35.5% was emulsion adsorption) in the adsorption of dispersed oil by coastal rocks, sediments, and bacterial strain particles respectively. Effects of controlling parameters, such as temperature, particle size and concentration on adsorption of petroleum hydrocarbons were described in detail. Most strikingly, adsorption concentration was followed a decreasing order of bacterial strain (0.5-2μm)>sediments (0.005-0.625mm)>coastal rocks (0.2-1cm). With particle concentration or temperature increased, adsorption concentration increased for coastal rocks particle but decreased for sediments particle. Besides, particle adsorption rate of petroleum hydrocarbons (n-alkanes and PAHs) was different among granular materials during 60 days. Copyright © 2017 Elsevier Ltd. All rights reserved.

Microbial inhibitory and radical scavenging activities of cold-pressed terpeneless Valencia orange (Citrus sinensis) oil in different dispersing agents.

Science.gov (United States)

Chalova, Vesela I; Crandall, Philip G; Ricke, Steven C

2010-04-15

Due to their low solubility in water, oil-based bioactive compounds require dispersion in a surface-active agent or appropriate solvents to ensure maximum contact with microorganisms. These combinations, however, may change their physical and/or chemical characteristics and consequently alter the desired functionality. The objective of this study was to determine the impact of selected dispersing agents, ethanol, dimethyl sulfoxide (DMSO), and Tween-80, on cold-pressed terpeneless (CPT) Valencia orange oil to function as a free radical scavenger and an antimicrobial food additive. When dissolved in ethanol or DMSO, the orange oil fraction had similar minimum inhibitory concentrations (MIC) for Listeria monocytogenes ATCC 19 115 (0.3% and 0.25% v/v respectively), which were significantly lower (P orange oil (up to 3%) in an aqueous solution of 0.1% Tween-80 yielded no inhibitory activities against any of the test bacteria. However, the 1% natural orange oil dispersed in Tween-80 exhibited 56.86% 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical inhibition versus 18.37% and 16.60% when the same level of orange oil was dissolved in DMSO or ethanol, respectively. At the same orange oil concentration, the oil/Tween-80 suspension yielded 57.92% neutralization of hydroxyl radicals. This represents 71.37% of the mannitol antioxidant activity, which was used as a positive control. These findings suggest that Tween-80 is an appropriate dispersing agent only if the antioxidant functionality is desired. If both antimicrobial and antioxidant properties are needed, the CPT Valencia orange oil should be dispersed in either DMSO or ethanol. (c) 2010 Society of Chemical Industry.

Toxicity of crude oils and a dispersant to the stony coral Madracis mirabilis

Energy Technology Data Exchange (ETDEWEB)

Elgershuizen, J H.B.W.; De Kruijf, H A.M.

1976-02-01

Coral reefs play a crucial role in the ecology of coastal tropical waters. In many areas they are now exposed to pollution hazards which have sometimes caused severe damage. Increasingly they are exposed to oil and, where clean-up methods are used, to dispersants. The report shows that the clean-up may be more damaging than the oil. (auth)

Stable dispersion of nanodiamonds in oil and their tribological properties as lubricant additives

Science.gov (United States)

Lee, Gyoung-Ja; Park, Jin-Ju; Lee, Min-Ku; Rhee, Chang Kyu

2017-09-01

Nanodiamonds (NDs) are innovative additives when a combination of mechanical, thermal, tribological, and dielectric properties are required. In this study, a surface modification with oleic acid (OA) is developed for the deaggregation and prolonged dispersion of NDs in oil, and the effect of the NDs as lubricant additives on the tribological properties of a steel substrate is investigated. The OA renders the ND surface hydrophobic and decreases the average particle size from 268.6 to 20.1 nm. The OA-treated NDs exhibit very stable dispersion in oil even after more than 10 days, compared with the untreated NDs. From the analyses of the friction coefficient, wear loss, and worn surfaces using a ball-on-disk wear test, it is concluded that a 0.05 wt% addition of OA-treated NDs in oil lubricant provides excellent friction and anti-wear properties with the friction coefficient being reduced by 23%.

Low Frequency Dispersion Mechanism of Dielectric Response for Oil-paper Insulation Diagnosis

Institute of Scientific and Technical Information of China (English)

ZHOU Lijun; LI Xianlang; WU Guangning

2013-01-01

Both the real part and imaginary part of complex permittivity approximately have a log-linear frequency dependency at low frequencies,especially at ultra-low frequencies under conditions of different moisture concentrations and temperatures,which is recognized as the low frequency dispersion (LFD).In order to explain this dispersion,a new mechanism of dielectric response of LFD of oil-paper insulation is proposed.A simplified one-dimensional mathematical model of concentration polarization carrier caused by slow migration is developed and solved,which indicates that ion mobility is closely related to the size of gap and the adsorption capacity of cellulose molecular chains to ions.A stochastic statistical model of the carrier mobility induced LFD is also developed.Moreover,actual tests under 50 ℃and 2％ moisture content were put forward,as well as simulations with according current waveforms.The simulation results agreed well with the experimental data in that concentration polarization of carriers caused by slow migration is the probable cause of low frequency dispersion ofdielectric response for oil-paper insulation diagnosis.

Chemical oil-spill dispersants: evaluation of three laboratory procedures for estimating performance

International Nuclear Information System (INIS)

Clayton, J.R.; Marsden, P.

1992-09-01

The report presents data from studies designed to evaluate characteristics of selected bench-scale test methods for estimating performance of chemical agents for dispersing oil from surface slicks into an underlying water column. In order to mitigate the effect of surface slicks with chemical dispersant agents, however, an on-scene coordinator must have information and an understanding of performance characteristics for available dispersant agents. Performance of candidate dispersant agents can be estimated on the basis of laboratory testing procedures that are designed to evaluate performance of different agents. Data presented in the report assist in the evaluation of candidate test methods for estimating performance of candidate dispersant agents. Three test methods were selected for evaluating performance: the currently accepted Revised Standard EPA test, Environmental Canada's Swirling Flask test, and the IFP-Dilution test

Low-shear rheology and sedimentation stability of coal-oil dispersions

Energy Technology Data Exchange (ETDEWEB)

Rutter, P. R.; Davies, J. M.; Jones, T. E.R.

1984-10-15

Stable coal-oil mixtures can be prepared by grinding coal particles in fuel oil. These products have been prepared by the British Petroleum Company plc and are referred to as Coal-Oil Dispersions (COD). One of the major problems associated with the production of DOD is the rapid assessment of the length of time the coal particles are likely to remain in suspension under a particular set of storage conditions. This paper describes a number of measurements of the low-shear rheology and sedimentation stability of a series of CODs prepared by grinding two types of coal in two different fuel oils. The results suggest that two types of COD are possible. One type exhibits complex rheological properties at low shear rates and does not produce a coal sediment, even after prolonged storage at 80/sup 0/C under dynamic conditions. The other exhibits near Newtonian behaviour and appears to form a sedimented layer of coal during storage.

Response surface analysis to improve dispersed crude oil biodegradation

Energy Technology Data Exchange (ETDEWEB)

Zahed, Mohammad A.; Aziz, Hamidi A.; Mohajeri, Leila [School of Civil Engineering, Universiti Sains Malaysia, Nibong Tebal, Penang (Malaysia); Isa, Mohamed H. [Civil Engineering Department, Universiti Teknologi PETRONAS, Tronoh, Perak (Malaysia)

2012-03-15

In this research, the bioremediation of dispersed crude oil, based on the amount of nitrogen and phosphorus supplementation in the closed system, was optimized by the application of response surface methodology and central composite design. Correlation analysis of the mathematical-regression model demonstrated that a quadratic polynomial model could be used to optimize the hydrocarbon bioremediation (R{sup 2} = 0.9256). Statistical significance was checked by analysis of variance and residual analysis. Natural attenuation was removed by 22.1% of crude oil in 28 days. The highest removal on un-optimized condition of 68.1% were observed by using nitrogen of 20.00 mg/L and phosphorus of 2.00 mg/L in 28 days while optimization process exhibited a crude oil removal of 69.5% via nitrogen of 16.05 mg/L and phosphorus 1.34 mg/L in 27 days therefore optimization can improve biodegradation in shorter time with less nutrient consumption. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Onset of entrainment and degree of dispersion in dual continuous horizontal oil-water flows

Energy Technology Data Exchange (ETDEWEB)

Al-Wahaibi, Talal [Department of Petroleum and Chemical Engineering, Sultan Qaboos University, P.O. Box 33, Al-Khoud, P.C. 123 (Oman); Angeli, Panagiota [Department of Chemical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom)

2009-04-15

The transition from stratified to dual continuous oil-water flow (where each phase retains its continuity but there is dispersion of one phase into the other) as well as the dispersed phase fractions in the layers of the dual continuous pattern, were studied experimentally. Transition to this pattern from stratified flow occurs when drops of one phase appear into the other (onset of entrainment). The studies were carried out in a 38 mm ID horizontal stainless steel test section using two different inlet geometries, a T- and a Y-junction. The patterns were visualized through a transparent acrylic section located at 7 m from the inlet using a high speed video camera. Phase distribution measurements in a pipe cross section were obtained just before the acrylic section with a local impedance probe and the results were used to calculate the volume fraction of each phase entrained into the other. The onset of entrainment was found to occur at lower superficial water velocities as the oil superficial velocities increased. However, the inlet geometry did not affect significantly the transition line. During dual continuous flow, the dispersion of one phase into the opposite was found to extend further away from the interface with increasing water superficial velocity for a certain oil superficial velocity. An increase in the superficial water velocity increased the entrained fraction of water in oil (E{sub w/o}) but there was no trend with the oil velocity. Similarly, an increase in the superficial oil velocity increased the fraction of oil drops in water (E{sub o/w}) but the water velocity had no clear effect. The entrainment fractions were affected by the inlet geometry, with the T-inlet resulting in higher entrainment than the Y-inlet, perhaps because of the increased mixing induced by the T-inlet. The difference between the two inlets increased as the oil and water velocities increased. (author)

Biodegradation of dispersed marine fuel oil in sediment under engineered pre-spill application strategy

International Nuclear Information System (INIS)

Hua, J.

2006-01-01

Biodegradation of marine fuel oil was studied by monitoring changes in residual oil and populations of microorganisms in marine sediments. Biodegradation rates for dispersant and soap water were 2.09 and 2.27 g/kg per day, respectively, under pre-application strategy, suggesting that the strategy may promote MFO dispersion and provide with sufficient source of food. The effect of temperature on the effectiveness of pre-application strategy is particularly obvious for the growth of fungi and Pseudomonas maltophilia. The effect of pre-application of soap water on the tolerance of aerobic bacteria, Escherichia coli, and P. maltophilia, was gradually diminished within 25-33 days. (author)

Latent effects of Iranian crude oil and a chemical oil dispersant on red sea molluscs

Energy Technology Data Exchange (ETDEWEB)

Eisler, R

1973-01-01

Predation rate of the gastropod drill, Drupa granulata, on the mussel, Mytilus variabilis, was measured over a period of 28 days after adults from both species had been immersed for 168 h in seawater solutions containing high sublethal concentrations (10 ml/liter) of Iranian crude oil. Predation rate was three times higher in controls than in the group where both predator and prey had been exposed initially; intermediate values were determined among groups where only one species had been treated initially. Fecundity of drills, as evidenced by number of egg cases deposited, was directly related to mussel consumption. In a similar study with a chemical oil dispersant, exposure to high (0.003 ml/liter) sublethal levels for 168 h did not affect markedly the rate at which mussels were destroyed and consumed during post-treatment. However, the fecundity of untreated drills feeding on untreated mussels (controls) was 3 to 10 times greater than among groups in which one or bothsc species had been exposed initially to dispersant. Except for mussels consumed by drills, there were no deaths during the post-treatment period in either study, and all organisms appeared normal.

Evaluation of the dispersion of oil refinery liquid effluent; Avaliacao da dispersao de efluente liquido de refinaria de petroleo

Energy Technology Data Exchange (ETDEWEB)

Mariano, Adriano Pinto; Silva, Ariovaldo Jose da; Oliveira, Valdenilson Jose Alves de; Angelis, Dejanira de Franceschi de [Universidade Estadual Paulista (UNESP), Rio Claro, SP (Brazil). Dept. de Bioquimica e Microbiologia. Inst. de Biociencias], e-mail: adrianomariano@yahoo.com.br

2010-07-15

In this paper, two techniques to evaluate the dispersion of the effluent of an oil refinery are presented. Thus, the dispersion plume was characterized by field measurements of electrical conductivity and by computational simulation (Cormix simulator). An oil refinery whose effluent is discharged on the Atibaia river (Paulinia/SP) is taken as study case. The behavior of the effluent was evaluated until 1000 m after the discharge. The results show that the measurement of electrical conductivity is a suitable technique to evaluate the dispersion of oil refinery wastewaters, since they have high conductivity and for this reason there is a strong contrast between the values of the wastewater and the ambient background. Furthermore, other water quality parameters had a dispersion behavior similar to that shown by the conductivity. The dispersion plume generated by the computational simulator showed high concordance with the field data. In this manner, computational simulation can be a useful tool to evaluate the dispersion of discharges considering hypothetical scenarios, as well as to design the discharge channel. (author)

Effects of dispersants on microbial growth and biodegradation of crude oils

Digital Repository Service at National Institute of Oceanography (India)

Bhosle, N.B.; Mavinkurve, S.

Four oil spill dispersants when used along (0.1% V/V) or in combination with Saudi Arabian Crude (0.5% V/V) were non-toxic to Arthrobacter simplex and Candida tropicalis. At a higher concentration of 0.6% (V/V) only D2 was found to be toxic to both...

Synthesis and membrane performance characterization of self-emulsified waterborne nitrocellulose dispersion modified with castor oil

Energy Technology Data Exchange (ETDEWEB)

Su, Xiuxia; Zhao, Qingxiao, E-mail: 934481965@qq.com; Zhang, Dan; Dong, Wei

2015-11-30

Graphical abstract: - Highlights: • Waterborne nitrocellulose dispersion modified with castor oil (CWNC) was synthesized successfully. • It is a kind of environment-friendly coatings, in which volatile organic content (VOC) is near zero. • Castor oil used as an internal crosslinking agent for WNC improved the properties of the coating. • When the mass fraction of castor oil to total reactants is 7%, emulsion and the coating are of the best comprehensive performance. - Abstract: Waterborne nitrocellulose dispersion modified with castor oil (CWNC) was designed and successfully synthesized by self emulsification and reaction among isophorone diisocyanate (IPDI) trimer, dimethylol propionic acid (DMPA), nitrocellulose (NC) and castor oil (C.O.). The CWNC was characterized by transmission electron microscope (TEM), Fourier transform infrared (FTIR) spectroscopy and thermal gravimetric analysis (TGA), etc. The particle size of CWNC increased with the increase of mass fraction of castor oil to total reactants, ω (C.O.). The morphology of particles is an approximate core–shell structure indicated by TEM. FTIR confirmed that the reactions (i.e. IPDI trimer and castor oil, IPDI trimer and NC) occurred, the NCO groups of IPDI trimer were consumed totally and the backbone of NC was retained. The water contact angle measurements confirmed that introduced castor oil increased hydrophobicity of the film, thereby increasing the contact angle. TGA revealed that the CWNC film had better thermal resistance.

Synthesis and membrane performance characterization of self-emulsified waterborne nitrocellulose dispersion modified with castor oil

International Nuclear Information System (INIS)

Su, Xiuxia; Zhao, Qingxiao; Zhang, Dan; Dong, Wei

2015-01-01

Graphical abstract: - Highlights: • Waterborne nitrocellulose dispersion modified with castor oil (CWNC) was synthesized successfully. • It is a kind of environment-friendly coatings, in which volatile organic content (VOC) is near zero. • Castor oil used as an internal crosslinking agent for WNC improved the properties of the coating. • When the mass fraction of castor oil to total reactants is 7%, emulsion and the coating are of the best comprehensive performance. - Abstract: Waterborne nitrocellulose dispersion modified with castor oil (CWNC) was designed and successfully synthesized by self emulsification and reaction among isophorone diisocyanate (IPDI) trimer, dimethylol propionic acid (DMPA), nitrocellulose (NC) and castor oil (C.O.). The CWNC was characterized by transmission electron microscope (TEM), Fourier transform infrared (FTIR) spectroscopy and thermal gravimetric analysis (TGA), etc. The particle size of CWNC increased with the increase of mass fraction of castor oil to total reactants, ω (C.O.). The morphology of particles is an approximate core–shell structure indicated by TEM. FTIR confirmed that the reactions (i.e. IPDI trimer and castor oil, IPDI trimer and NC) occurred, the NCO groups of IPDI trimer were consumed totally and the backbone of NC was retained. The water contact angle measurements confirmed that introduced castor oil increased hydrophobicity of the film, thereby increasing the contact angle. TGA revealed that the CWNC film had better thermal resistance.

CHEMICAL OIL SPILL DISPERSANTS: UPDATE STATE-OF-THE- ART ON MECHANISM OF ACTION AND LABORATORY TESTING FOR PERFORMANCE

Science.gov (United States)

Chemical dispersants are formulations designed to facilitate dispersion of an oil slick into small droplets that disperse to non-problematic concentrations in an underlying water column. This project had two primary objectives: (1) update information on mechanisms of action of ...

Estimating sub-surface dispersed oil concentration using acoustic backscatter response.

Science.gov (United States)

Fuller, Christopher B; Bonner, James S; Islam, Mohammad S; Page, Cheryl; Ojo, Temitope; Kirkey, William

2013-05-15

The recent Deepwater Horizon disaster resulted in a dispersed oil plume at an approximate depth of 1000 m. Several methods were used to characterize this plume with respect to concentration and spatial extent including surface supported sampling and autonomous underwater vehicles with in situ instrument payloads. Additionally, echo sounders were used to track the plume location, demonstrating the potential for remote detection using acoustic backscatter (ABS). This study evaluated use of an Acoustic Doppler Current Profiler (ADCP) to quantitatively detect oil-droplet suspensions from the ABS response in a controlled laboratory setting. Results from this study showed log-linear ABS responses to oil-droplet volume concentration. However, the inability to reproduce ABS response factors suggests the difficultly in developing meaningful calibration factors for quantitative field analysis. Evaluation of theoretical ABS intensity derived from the particle size distribution provided insight regarding method sensitivity in the presence of interfering ambient particles. Copyright © 2013 Elsevier Ltd. All rights reserved.

Development of a dispersant-use decision-making system for oil spills in the U. S. Gulf of Mexico

Energy Technology Data Exchange (ETDEWEB)

Trudel, B K; Ross, S L; Belore, R C; Jessiman, B J

1987-12-01

A computerized system to aid in making real-time dispersant-use decisions for oil spills in the U.S. Gulf of Mexico is due for completion in early 1988. The system can predict the impact of an oil spill in the Gulf if it is either treated with dispersants or left untreated. The method works as follows. A computerized map of the untreated spill is produced showing the predicted location and concentration of the spilled oil as a function of time after the initial discharge. This map is then compared with a series of computerized maps of 70 important Gulf resources that might suffer from the effects of the spill. A geographical information system with extensive spatial analytical capabilities is then used to calculate the proportion of each resource that is affected by the spill at specified levels of oil concentration. Using a series of resource-specific impact assessment algorithms that link information on oil concentration and resource sensitivity, estimates of impact are then computed for each resource. The entire procedure is repeated for the same spill if chemically dispersed. The result is a list of resource-specific impacts from the untreated spill and a similar list for the treated decision is made by comparing the lists. Preliminary indications are that the computer will take less than one hour to derive a dispersant-use decision for the most complex case involving all 70 resources included in the system. 3 figs. 1 tab.

Fuel oil and dispersant toxicity to the Antarctic sea urchin (Sterechinus neumayeri).

Science.gov (United States)

Alexander, Frances J; King, Catherine K; Reichelt-Brushett, Amanda J; Harrison, Peter L

2017-06-01

The risk of a major marine fuel spill in Antarctic waters is increasing, yet there are currently no standard or suitable response methods under extreme Antarctic conditions. Fuel dispersants may present a possible solution; however, little data exist on the toxicity of dispersants or fuels to Antarctic species, thereby preventing informed management decisions. Larval development toxicity tests using 3 life history stages of the Antarctic sea urchin (Sterechinus neumayeri) were completed to assess the toxicity of physically dispersed, chemically dispersed, and dispersant-only water-accommodated fractions (WAFs) of an intermediate fuel oil (IFO 180, BP) and the chemical dispersant Slickgone NS (Dasic International). Despite much lower total petroleum hydrocarbon concentrations, physically dispersed fuels contained higher proportions of low-to-intermediate weight carbon compounds and were generally at least an order of magnitude more toxic than chemically dispersed fuels. Based on concentrations that caused 50% abnormality (EC50) values, the embryonic unhatched blastula life stage was the least affected by fuels and dispersants, whereas the larval 4-armed pluteus stage was the most sensitive. The present study is the first to investigate the possible implications of the use of fuel dispersants for fuel spill response in Antarctica. The results indicate that the use of a fuel dispersant did not increase the hydrocarbon toxicity of IFO 180 to the early life stages of Antarctic sea urchins, relative to physical dispersal. Environ Toxicol Chem 2017;36:1563-1571. © 2016 SETAC. © 2016 SETAC.

Chemical countermeasures: Dispersants overview of dispersant use (including application) and research issues

International Nuclear Information System (INIS)

Butler, J.N.

1992-01-01

I will attempt in twenty minutes to summarize the state of research on oil spill dispersants as I perceive it. The expertise I bring to this task includes 20 years of experience with the fate and effects of petroleum in the marine environment, including participation in the 1973 and 1981 NRC studies and three years as chairman of the NRC committee on oil spill dispersants. I More recently I served on a committee of the International Maritime Organization which reviewed the open-quotes Impact of oil and related chemicals and wastes on the marine environment.close quotes That report will be published this year. However, my statements in this paper are not made as a representative of either NRC or IMO. They are my own interpretation of scientific literature cited in the above reviews. Dispersants are chemical formulations, which include surface active agents, designed to decrease the interfacial tension between oil and water. Because the first attempts to disperse oil on a large scale, at the Torrey Canyon spill of 1967, used highly toxic degreasing agents, dispersants have an undeserved reputation for toxicity. In fact, for twenty years dispersant formulations have been developed with an emphasis on reducing their toxicity to marine life. The dispersal of oil in water has been documented in the laboratory by dozens of papers (see references in NRC 1989, pp 70-79), and in the field by dozens of studies (NRC 1989, pp 165- 193). The toxicity of commercial dispersant formulations (NRC 1989, pp 81-123) and dispersed oil (NRC 1989, pp 123-147) has been tested on a wide variety of marine organisms ranging from algae to salmonid fishes. The NRC review has been updated by the IMO/GESAMP (1992) study, but the conclusions remain unchanged

Simulating oil droplet dispersal from the Deepwater Horizon spill with a Lagrangian approach

Science.gov (United States)

North, Elizabeth W.; Schlag, Zachary; Adams, E. Eric; Sherwood, Christopher R.; He, Ruoying; Hyun, Hoon; Socolofsky, Scott A.

2011-01-01

An analytical multiphase plume model, combined with time-varying flow and hydrographic fields generated by the 3-D South Atlantic Bight and Gulf of Mexico model (SABGOM) hydrodynamic model, were used as input to a Lagrangian transport model (LTRANS), to simulate transport of oil droplets dispersed at depth from the recent Deepwater Horizon MC 252 oil spill. The plume model predicts a stratification-dominated near field, in which small oil droplets detrain from the central plume containing faster rising large oil droplets and gas bubbles and become trapped by density stratification. Simulated intrusion (trap) heights of ∼ 310–370 m agree well with the midrange of conductivity-temperature-depth observations, though the simulated variation in trap height was lower than observed, presumably in part due to unresolved variability in source composition (percentage oil versus gas) and location (multiple leaks during first half of spill). Simulated droplet trajectories by the SABGOM-LTRANS modeling system showed that droplets with diameters between 10 and 50 μm formed a distinct subsurface plume, which was transported horizontally and remained in the subsurface for >1 month. In contrast, droplets with diameters ≥90 μm rose rapidly to the surface. Simulated trajectories of droplets ≤50 μm in diameter were found to be consistent with field observations of a southwest-tending subsurface plume in late June 2010 reported by Camilli et al. [2010]. Model results suggest that the subsurface plume looped around to the east, with potential subsurface oil transport to the northeast and southeast. Ongoing work is focusing on adding degradation processes to the model to constrain droplet dispersal.

Entropy Production in Pipeline Flow of Dispersions of Water in Oil

Directory of Open Access Journals (Sweden)

Rajinder Pal

2014-08-01

Full Text Available Entropy production in pipeline adiabatic flow of water-in-oil emulsions is investigated experimentally in three different diameter pipes. The dispersed-phase (water droplets concentration of emulsion is varied from 0 to 41% vol. The entropy production rates in emulsion flow are compared with the values expected in single-phase flow of Newtonian fluids with the same properties (viscosity and density. While in the laminar regime the entropy production rates in emulsion flow can be described adequately by the single-phase Newtonian equations, a significant deviation from single-phase flow behavior is observed in the turbulent regime. In the turbulent regime, the entropy production rates in emulsion flow are found to be substantially smaller than those expected on the basis of single-phase equations. For example, the entropy production rate in water-in-oil emulsion flow at a dispersed-phase volume fraction of 0.41 is only 38.4% of that observed in flow of a single-phase Newtonian fluid with the same viscosity and density, when comparison is made at a Reynolds number of 4000. Thus emulsion flow in pipelines is more efficient thermodynamically than single-phase Newtonian flow.

Microbial communities related to biodegradation of dispersed Macondo oil at low seawater temperature with Norwegian coastal seawater

Science.gov (United States)

Brakstad, Odd G; Throne-Holst, Mimmi; Netzer, Roman; Stoeckel, Donald M; Atlas, Ronald M

2015-01-01

The Deepwater Horizon (DWH) accident in 2010 created a deepwater plume of small oil droplets from a deepwater well in the Mississippi Canyon lease block 252 (‘Macondo oil’). A novel laboratory system was used in the current study to investigate biodegradation of Macondo oil dispersions (10 μm or 30 μm median droplet sizes) at low oil concentrations (2 mg l−1) in coastal Norwegian seawater at a temperature of 4–5°C. Whole metagenome analyses showed that oil biodegradation was associated with the successive increased abundances of Gammaproteobacteria, while Alphaproteobacteria (Pelagibacter) became dominant at the end of the experiment. Colwellia and Oceanospirillales were related to n-alkane biodegradation, while particularly Cycloclasticus and Marinobacter were associated with degradation of aromatic hydrocarbons (HCs). The larger oil droplet dispersions resulted in delayed sequential changes of Oceanospirillales and Cycloclasticus, related with slower degradation of alkanes and aromatic HCs. The bacterial successions associated with oil biodegradation showed both similarities and differences when compared with the results from DWH field samples and laboratory studies performed with deepwater from the Gulf of Mexico. PMID:26485443

Dispersant effectiveness: Studies into the causes of effectiveness variations

International Nuclear Information System (INIS)

Fingas, M.F.; Kyle, D.; Tennyson, E.

1995-01-01

Effectiveness, a key issue of using dispersants, is affected by many interrelated factors. The principal factors involved are the oil composition, dispersant formulation, sea surface turbulence and dispersant quantity. Oil composition is a very strong determinant. Current dispersant formulation effectiveness correlates strongly with the amount of saturate component in the oil. The other components of the oil, the asphaltenes, resins or polars and aromatic fractions show a negative correlation with the dispersant effectiveness. Viscosity is also a predictor of dispersant effectiveness and may have an effect because it is in turn determined by oil composition. Dispersant composition is significant and interacts with oil composition. Dispersants show high effectiveness at HLB values near 10. Sea turbulence strongly affects dispersant effectiveness.Effectiveness rises with increasing turbulence to a maximum value. Effectiveness for current commercial dispersants is gaussian around a peak salinity value. Peak effectiveness is achieved at very high dispersant quantities--at a ratio of 1:5, dispersant-to-oil volume. Dispersant effectiveness for those oils tested and under the conditions measured, is approximately logarithmic with dispersant quantity and will reach about 50% of its peak value at a dispersant to oil ratio of about 1:20 and near zero at a ratio of about 1:50

Macondo-1 well oil in sediment and tarballs from the northern Gulf of Mexico shoreline

Science.gov (United States)

Wong, Florence L.; Rosenbauer, Robert J.; Campbell, Pamela L.; Lam, Angela; Lorenson, T.D.; Hostettler, Frances D.; Thomas, Burt

2011-01-01

From April 20 through July 15, 2010, an estimated 4.4 million barrels (1 barrel = 42 gallons [~700,000 cu m]) of crude oil spilled into the northern Gulf of Mexico (nGOM) from the ruptured British Petroleum (BP) Macondo-1 (M-1) well after the explosion of the drilling platform Deepwater Horizon. In addition, ~1.84 million gallons (~7,000 cu m) of hydrocarbon-based Corexit dispersants were applied to the oil both on and below the sea surface (Operational Science Advisory Team, 2010). An estimate of the total extent of the surface oil slick, derived from wind, ocean currents, aerial photography, and satellite imagery, was 68,000 square miles (~180,000 sq km; Amos and Norse, 2010). Spilled oil from this event impacted sensitive habitat along the shores of the nGOM. In response to this environmental catastrophe, the U.S. Geological Survey (USGS) collected coastal sediment and tarball samples along the shores of the nGOM from Texas to Florida before and after oil made landfall. These sites included priority areas of the nGOM at highest risk for oil contamination. These areas included coastal wetlands, shorelines, and barrier islands that could suffer severe environmental damage if a significant amount of oil came ashore. Samples were collected before oil reached land from 69 sites; 49 were revisited to collect samples after oil landfall. This poster focuses on the samples from locations that were sampled on both occasions. The USGS samples and one M-1 well-oil sample provided by BP were analyzed for a suite of diagnostic geochemical biomarkers. Aided by multivariate statistical analysis, the M-1 well oil was not detected in the samples collected before landfall but have been identified in sediment and tarballs collected from Louisiana, Alabama, Mississippi, and Florida after landfall. None of the sediment hydrocarbon extracts from Texas correlated with the M-1 well oil. Oil-impacted sediment is confined to the shoreline adjacent to the cumulative oil slick of the

Non-Dispersive Infrared Sensor for Online Condition Monitoring of Gearbox Oil

Directory of Open Access Journals (Sweden)

Markus S. Rauscher

2017-02-01

Full Text Available The condition of lubricating oil used in automotive and industrial gearboxes must be controlled in order to guarantee optimum performance and prevent damage to machinery parts. In normal practice, this is done by regular oil change intervals and routine laboratory analysis, both of which involve considerable operating costs. In this paper, we present a compact and robust optical sensor that can be installed in the lubrication circuit to provide quasi-continuous information about the condition of the oil. The measuring principle is based on non-dispersive infrared spectroscopy. The implemented sensor setup consists of an optical measurement cell, two thin-film infrared emitters, and two four-channel pyroelectric detectors equipped with optical bandpass filters. We present a method based on multivariate partial least squares regression to select appropriate optical bandpass filters for monitoring the oxidation, water content, and acid number of the oil. We perform a ray tracing analysis to analyze and correct the influence of the light path in the optical setup on the optical parameters of the bandpass filters. The measurement values acquired with the sensor for three different gearbox oil types show high correlation with laboratory reference data for the oxidation, water content, and acid number. The presented sensor can thus be a useful supplementary tool for the online condition monitoring of lubricants when integrated into a gearbox oil circuit.

Increased mineral oil bioavailability in slurries by monovalent cation-induced dispersion

International Nuclear Information System (INIS)

Jonge, H. de; Verstraten, J.M.

1995-01-01

Bioavailability of apolar contaminants is an important limiting factor for microbial reclamation of polluted soils. This paper describes a laboratory study of the relation between microaggregate stability and bioavailability of mineral oil in soil-water slurries. The stability of microaggregates in slurries is regulated by the valence and surface affinity of the cations in the system, and by the complexing anion P 2 O 7 4- (metaphosphate). A silt loam, contaminated with a weathered gas oil, was collected from an oil refinery site. Degradation rates were monitored in small-scale incubations at solid:liquid ratios of 1:5 (w/w). The solution contained Ca, Na, or K as the dominant cation. The levels of nutrients and metaphosphate were varied. Biodegradation rates increased with the sequence Ca 2 treatment. Measurements of the particle size distribution the slurry showed that an increase in the finer fractions qualitatively correlated with enhanced biodegradation. This is a strong indication that dispersion of the microaggregates increased bioavailability of the contaminant

Evaluation of nano emulsion containing asphaltenes dispersant additive in dehydration of oil; Avaliacao de nanoemulsoes contendo aditivo dispersante de asfaltenos na desidratacao de petroleo

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Priscila F. de; Rodrigues, Jessica S.; Mansur, Claudia R.E. [Universidade Federal do Rio de Janeiro/ Instituto de Macromoleculas/ Laboratorio de Macromoleculas e Coloides na Industria de Petroleo, Rio de Janeiro, RJ (Brazil)], e-mail: prisfrias@hotmail.com

2011-07-01

Due to the problem of the formation of emulsions type water-oil during oil production, new alternatives of the breakdown of these emulsions have been proposed over the years. Several polymers have been used to destabilize these emulsions and among them are those based on polyphenylene ether. The aim of this study was to develop nanoemulsions type oil / water, where an asphaltenes dispersant additive was dissolved in dispersed phase in order to evaluate them as a new alternative in the breakdown of oil emulsions. The nanoemulsions were prepared in the presence of surfactant based on polyoxide using a high pressure homogenizer (HPH). We obtained stable nanoemulsions for more than 30 days in the presence or absence of additive. These nanoemulsions were effective in water /oil phase separation, and the nanoemulsion containing the dispersant additive provided a faster separation of these phases. (author)

Evaluation of field-collected drifter and subsurface fluorescein dye concentration data and comparisons to high frequency radar surface current mapping data for dispersed oil transport modeling

Energy Technology Data Exchange (ETDEWEB)

Payne, J.R. [Payne Environmental Consultants Inc., Encinitas, CA (United States); Terrill, E.; Carter, M.; Otero, M.; Middleton, W.; Chen, A. [Scripps Inst. of Oceanography, La Jolla, CA (United States); French McCay, D.; Mueller, C.; Jayko, K. [Applied Science Associates Inc., Narragansett, RI (United States); Nordhausen, W.; Lewis, R.; Lampinen, M.; Evans, T. [California Dept. of Fish and Game, San Diego, CA (United States). Office of Spill Prevention and Response; Ohlmann, C. [California Univ., Santa Barbara, CA (United States); Via, G.L.; Ruiz-Santana, H.; Maly, M.; Willoughby, B.; Varela, C. [United States Coast Guard Pacific Strike Team, Novato, CA (United States); Lynch, P.; Sanchez, P. [Marine Spill Response Corp., San Diego, CA (United States)

2007-07-01

Extensive coastal areas in the United States have been designated as pre-approved zones for dispersant applications in the event of an oil spill. Although the use of dispersants may reduce impacts to wildlife and shoreline habitats, it is recognized that the dispersed oil may cause impacts to organisms in the water column. The State of California Department of Fish and Game Office of Spill Prevention and Response is currently using oil spill fate and transport modeling to address this issue. The purpose is to develop the time and spatial scales, and equipment needs for a formal dispersed oil monitoring plan (DOMP) to document hydrocarbon water column concentrations, potentially exposed zooplankton, and the impact of the oil spills with and without dispersant use. A series of 7 fluorescein dye releases were completed off the coast of San Diego, California in order to test the operational framework for repeated sampling of dispersed oil plumes as outlined in the DOMP. The ability of high-frequency radar to provide surface current input data to oil spill models was also evaluated. The dye concentrations were measured over three spatial dimensions and time in order to verify the model-predicted movement of subsurface dye. Surface current fields at varying depths were also measured and the subsurface dye plume structure was mapped using a GPS coupled towed-fluorometer equipped with pressure sensors. Measurements were compared with data from traditional special monitoring of applied response technology (SMART). The database acquired through this program represents a technical resource that can help physical and chemical oceanographers, modelers, spill response and contingency planners involved in the debate of whether or not to use dispersants to mitigate near shore and open ocean marine oil spills. 14 refs., 2 tabs., 14 figs.

Toxicity of Chevron Escravos crude oil and chemical dispersant on guinea pig testicular function.

Science.gov (United States)

Afonne, Onyenmechi Johnson; Onyiaorah, Igwebuike Victor; Orisakwe, Orish Ebere

2013-01-01

Chemical contaminants have been found to affect reproductive functions in mammals. This study investigated the effect of Chevron Escravos crude oil and Emulsol L.W. dispersant on the testicular functions of guinea pig. Eight groups of seven sexually mature male guinea pigs each were given 1250, 2500, or 5000 mg/kg of crude oil and dispersant for 7 days. The fluid and food intake and body weight of the animals were measured daily throughout the study. After the exposure period, sperm quality analysis was carried out, and fructose and lactate dehydrogenase were analyzed in tissue homogenate, while testosterone and estradiol were assayed in blood. The right testis was also processed for histological analysis. The epididymal sperm number and fructose level of treated animals showed a significant dose-dependent decrease (pguinea pigs. The possible mechanism of toxicity is suggested to be by stimulation of hormone production from the adrenal cortex, causing a negative feedback on gonadotropin-releasing hormone in the pituitary gland to suppress spermatogenesis.

Effect of a Dispersant Agent in Fine Coal Recovery from Washery Tailings by Oil Agglomeration (Preliminary Study)

Science.gov (United States)

Yasar, Özüm; Uslu, Tuncay

2017-12-01

Among the fine coal cleaning methods, the oil agglomeration process has important advantages such as high process recovery, more clean product, simple dewatering stage. Several coal agglomeration studies have been undertaken recently and effects of different variables on the process performance have been investigated. However, unlike flotation studies, most of the previous agglomeration studies have not used dispersing agents to minimize slime coating effects of clays. In this study, agglomeration process was applied for recovery of fine coals from coal washery tailings containing remarkable amount of fine coal. Negative effect of fine clays during recovery was tried to be eliminated by using dispersing agent instead of de-sliming. Although ash reductions over 90 % were achieved, performance remained below expectations in terms of combustible matter recovery. However, this study is a preliminary one. It is considered that more satisfied results will be obtained in the next studies by changing the variables such as solid ratio, oil dosage, dispersant type and dosage.

Evaluating the biodegradability and effects of dispersed oil using Arctic test species and conditions: phase 2 activities

Energy Technology Data Exchange (ETDEWEB)

MacFarlin, Kelly M.; Perkins, Robert A. [University of Alaska Fairbanks (United States)], email: raperkins@alaska.edu; Gardiner, William W.; Word, Jack D. [NewFields NorthWest (United States)

2011-07-01

In the event of a marine oil spill, managers have to make correct and rapid decisions, weighing a number of possibilities, which include natural attenuation, mechanical recovery, in situ burning, and/or chemical dispersion. To do this, the relative toxicity of physically and chemically dispersed fresh oil and the rates of biodegradation for fresh and weathered oil need to be understood in advance. A joint industry program was established in 2008 to research and discuss these areas. Phase 1 activities included determining the species relevant to the Beaufort and Chukchi Sea ecosystems, creating and setting up a toxicity and biodegradation laboratory with a cold room in Barrow, Alaska, developing collection and culture methods for test organisms, and developing toxicity and biodegradation test protocols. The second phase of this now completed research is discussed in this paper. It consisted of toxicity testing of the local environmentally significant species, the copepod (C. glacialis), Arctic cod (B. saida), and larval sculpin (Myoxocephalus sp.).

Dispersant field testing : a review of procedures and considerations

International Nuclear Information System (INIS)

Fingas, M.F.

2004-01-01

The effectiveness of a dispersant is defined by the amount of oil that the dispersant puts into the water column compared to the amount of oil that was initially spilled. Effectiveness is generally determined visually in plumes of dispersed oil that are visible from ships and aircraft. This paper describes 25 specific issues and technical concerns regarding field testing of dispersant effectiveness. Recent field tests were reviewed and literature that relates to testing procedures was sited. The 25 factors that are important for the appropriate outcome of dispersant field experiments include: mass balance; proper controls; analytical method; differential plume movement; time lag and length of time followed; mathematics of calculation and integration; lower and upper limits of analytical methods; use of remote sensing; thickness measurement; behaviour of oil with surfactant content; surfactant stripping; tracking surface oil and dispersed oil; recovering surface oil; visibility of oil from the surface; background levels of hydrocarbons; fluorescence of dispersant; herding; emulsion breaking; application success; heterogeneity of slick and plume; deposition measurements; true analytical standards; effect of wind on dispersant and slick; dispersant run-off; and weathering of the oil. It was concluded that the most important factors are the ability to determine mass balance, use proper controls, analytical methods and to avoid procedures that give incorrect results. 34 refs., 4 tabs., 1 fig

Synthesis and membrane performance characterization of self-emulsified waterborne nitrocellulose dispersion modified with castor oil

Science.gov (United States)

Su, Xiuxia; Zhao, Qingxiao; Zhang, Dan; Dong, Wei

2015-11-01

Waterborne nitrocellulose dispersion modified with castor oil (CWNC) was designed and successfully synthesized by self emulsification and reaction among isophorone diisocyanate (IPDI) trimer, dimethylol propionic acid (DMPA), nitrocellulose (NC) and castor oil (C.O.). The CWNC was characterized by transmission electron microscope (TEM), Fourier transform infrared (FTIR) spectroscopy and thermal gravimetric analysis (TGA), etc. The particle size of CWNC increased with the increase of mass fraction of castor oil to total reactants, ω (C.O.). The morphology of particles is an approximate core-shell structure indicated by TEM. FTIR confirmed that the reactions (i.e. IPDI trimer and castor oil, IPDI trimer and NC) occurred, the NCO groups of IPDI trimer were consumed totally and the backbone of NC was retained. The water contact angle measurements confirmed that introduced castor oil increased hydrophobicity of the film, thereby increasing the contact angle. TGA revealed that the CWNC film had better thermal resistance.

Contaminant levels in Gulf of Mexico reef fish after the Deepwater Horizon oil spill as measured by a fishermen-led testing program.

Science.gov (United States)

Fitzgerald, Timothy P; Gohlke, Julia M

2014-01-01

The BP oil disaster posed a significant threat to the U.S. seafood industry. Invertebrates (shrimp, oyster, crab) and other nearshore species comprised the majority of postspill testing by federal and state agencies. Deeper water finfish were sampled less frequently, despite population ranges that overlapped with affected waters. We report on a voluntary testing program with Gulf of Mexico commercial fishermen to ensure the safety of their catch. Seven species of reef fish were tested for polycyclic aromatic hydrocarbons, several metals, and a constituent of Corexit 9500A and 9527A dispersants. Only two of 92 samples had detectable levels of benzo(a)pyrene-equivalents (a combined measure of carcinogenic potency across 7 different PAHs), which were still below federal safety thresholds. PAH ratios for these samples suggest pyrogenic (not petrogenic) contamination - indicating potential sources other than Deepwater Horizon. Metals were largely absent (cadmium, lead) or consistent with levels previously reported (mercury, arsenic). One notable exception was tilefish, which showed mercury concentrations lower than expected. We did not detect dispersant in any of our samples, indicating that it was not present in these species during the study period. Our findings suggest minimal risk to public health from these seafoods as a result of the disaster; however, the most contaminated areas were not sampled through this program.

Modélisation de la combustion de fuels lourds prenant en compte la dispersion des asphaltènes Modeling Heavy Fuel-Oil Combustion (While Considering Or Including Asphaltene Dispersion

Directory of Open Access Journals (Sweden)

Audibert F.

2006-11-01

Full Text Available Divers modèles, ayant pour but de prédire le taux d'imbrûlés solides lors de la combustion du fuel lourd, ont été mis au point dans le passé. Les paramètres entrant en ligne de compte sont le plus souvent les teneurs en résidus lourds hydrocarbonés (asphaltènes précipités au pentane ou à l'heptane et carbone Conradson et en métaux : c'est le cas des modèles Exxon et Shell développés respectivement en 1979 et 1981. D'autres modèles tiennent compte, en plus de la composition du fuel, de son mode d'atomisation, de son mode de diffusion dans le foyer et de la cinétique de combustion : on peut citer les travaux du Laboratoire Energie du MIT publiés en 1986. Néanmoins, ces facteurs ne sont pas les seuls à intervenir : l'expérience a montré que l'état de dispersion des asphaltènes peut jouer également un grand rôle, notamment dans le cas d'installations de combustion à injection mécanique, pour lesquelles la dispersion des gouttelettes n'est pas aussi fine que pour des installations munies d'une injection assistée par la vapeur. Cette influence de la dispersion des asphaltènes sur la combustion a été mise en évidence dans le passé par l'utilisation d'additifs dispersants et également par la combustion de fuels lourds constitués par dilution d'asphaltes précipités au pentane avec un gas-oil de cracking catalytique de raffinerie (LCO. Ce sont ces fuels que l'on a considérés dans la présente étude. L'effet de ce facteur dispersion n'a pas été quantifié jusqu'alors, la difficulté étant de définir une grandeur mesurable représentant la répartition des agglomérats d'asphaltènes. Dans cette étude, on a essayé en un premier temps de faire une approche fractale de la répartition des asphaltènes à partir de clichés (préparés par la société Total, cette méthode ayant déjà été utilisée avec succès pour décrire des structures d'aspects comparables. Malheureusement, on s'est heurté à des

The Braer incident: Dispersion in action

International Nuclear Information System (INIS)

Thomas, D.

1993-01-01

In January 1993, the tanker Braer foundered in the Shetland Islands and pollution from the cargo of 85,000 tonnes of Gullfaks crude oil was reported almost immediately. The tanker was battered by storm winds and finally broke up, spilling the remainder of its cargo into the bay at Garth's Ness. Dispersants were applied to the oil plumes, assisting the significant natural dispersion. Shoreline protection and cleanup activities included construction of spade dams and sorbent barriers. Oil concentrations in water, air, sediment, and fish were monitored. The sampling program undertaken during the spill period is described. Measured hydrocarbon concentrations in salmon farm areas were not observed to rise above 4 ppM. The high rates of dispersion make the Braer incident worthy of detailed study both in terms of understanding the mechanism of the dispersion process and also in assessing the environmental effects following high dispersed oil concentrations. Estimates of the spill's mass balance are provided for the bay at Garth's Ness, where the highest oil concentrations were observed, and along the 26 km of coastline which received the most significant concentrations of dispersed oil. Contrary to laboratory experiments which showed that the Gullfaks crude would emulsify at the high sea states prevailing at the time, the Braer spill did not emulsify and most of the oil released was dispersed naturally into the water column. It appears that it is most appropriate to model the Braer spill as a spillage of floating or dissolved chemical. 4 refs., 4 figs., 6 tabs

The particulate matter dispersion studies from a local palm oil mill

International Nuclear Information System (INIS)

Abdullah, L.C.; Wong, L. L.; Amnorzahira, A.; Sa'ari, M.; Abdul Rashid, M. S.; Salmiaton Ali

2006-01-01

The appearance of industrial emissions and the degradation of scenic vistas are two characteristics of air pollution that humans object. Reduction in visibility suggests worsening pollution levels. The emissions from mobile source and stationary source are the major source of air pollutions contribution in Malaysia. Suspended particulate matter (SPM). The consequence of increasing the particulate concentrations, the particulate matter dissolves with vapour and grows into droplets when the humidity exceeds approximately 70% and causing opaque situation know as haze. This work focuses on the dispersion particulate matter from palm oil mill. The data obtained serves the purpose of modeling the transport of particulate matter for obtaining permits and prevention of significant deterioration (PSD) to the environment. Gaussian Plume Model from a point source, subject to various atmospheric conditions is used to calculate particulate matter concentration then display the distribution of plume dispersion using geographic information system (GIS). The calculated particulate matter concentration is evaluated using Transilient Matrice function. Atmospheric Stability, mixing height, wind direction, wind speed, natural and artificial features play an important role in dispersion process. High concentration area exhibits immediately under prevailing wind direction. (Author)

Comparative Toxicity of Louisiana Sweet Crude Oil (LSC) and Chemically Dispersed LSC to Two Gulf of Mexico Aquatic Test Species.

Science.gov (United States)

Environmental Protection Agency released peer reviewed results from the second phase of its independent toxicity testing on mixtures of eight oil dispersants with Louisiana Sweet Crude Oil. EPA conducted the tests as part of an effort to ensure that EPA decisions remain grounded ...

An insight into spore dispersal of Ganoderma boninense on oil palm.

Science.gov (United States)

Sanderson, F R

2005-01-01

The disease of oil palm caused by Ganoderma boninense, although universally referred to as Ganoderma basal stem rot, occurs in three very distinct phases, with basal stem rot only part of the disease cycle. G. boninense also causes a seedling disease and an upper stem rot. An understanding of spore dispersal provides an insight into where spores of G. boninense have a role in the infection process. This role will be discussed in relation to each of these three infection phases. This understanding is a critical component of developing a successful disease control strategy.

Emergence, growth, and dispersal of Chironomidae in reclaimed wetlands in the Athabasca oil sands region of Alberta

Energy Technology Data Exchange (ETDEWEB)

Kennedy, K.; Ciborowski, J. [Windsor Univ., ON (Canada)

2010-07-01

Concerns over the environmental impacts of oil sands extraction in northeastern Alberta has increased as the industry continues to expand. This study examined if the emergence, growth, and dispersal of Chironomidae differ in reclaimed wetlands constructed with oil sands process materials (OSPM) when compared with growth in reference wetlands. Five floating 30 cm diameter halo traps were deployed in various wetlands for a 24 hour period. Exuviae trapped in the surface water film were then collected, identified, and counted. Chironomids grown in laboratories from egg masses collected from 2 OSPM-affected wetlands and 2 reference wetlands were paired according to geographic proximity under controlled conditions for 1 generation. Chironomid larval growth was quantified in situ in the wetlands by reciprocally transferring second instar, second generation culture larva. The dispersal of the larvae was quantified by tabulating the number of adults caught in sticky insect traps located along 3 radially-arranged transects in each wetland. A preliminary analysis has suggested that fewer chironomids emerged from the OSPM-affected wetlands. No differences in dispersal distance between the OSPM-affected and reference wetlands were observed.

Emergence, growth, and dispersal of Chironomidae in reclaimed wetlands in the Athabasca oil sands region of Alberta

International Nuclear Information System (INIS)

Kennedy, K.; Ciborowski, J.

2010-01-01

Concerns over the environmental impacts of oil sands extraction in northeastern Alberta has increased as the industry continues to expand. This study examined if the emergence, growth, and dispersal of Chironomidae differ in reclaimed wetlands constructed with oil sands process materials (OSPM) when compared with growth in reference wetlands. Five floating 30 cm diameter halo traps were deployed in various wetlands for a 24 hour period. Exuviae trapped in the surface water film were then collected, identified, and counted. Chironomids grown in laboratories from egg masses collected from 2 OSPM-affected wetlands and 2 reference wetlands were paired according to geographic proximity under controlled conditions for 1 generation. Chironomid larval growth was quantified in situ in the wetlands by reciprocally transferring second instar, second generation culture larva. The dispersal of the larvae was quantified by tabulating the number of adults caught in sticky insect traps located along 3 radially-arranged transects in each wetland. A preliminary analysis has suggested that fewer chironomids emerged from the OSPM-affected wetlands. No differences in dispersal distance between the OSPM-affected and reference wetlands were observed.

Phase behavior and phase inversion for dispersant systems

International Nuclear Information System (INIS)

Solheim, A.; Brandvik, P.J.

1991-06-01

This report describes some preliminary phase behavior studies and phase inversion temperature measurements in seawater, bunker oil and dispersant. The objectives have been to find new ways of characterizing dispersants for dispersing oil spill at sea and, perhaps, to throw new lights on the mechanism of dispersion formation (oil-in-water emulsification). The work has been focussed on the relation to phase behavior and the existence of microemulsion in equilibrium with excess oil and water phases. The dispersing process is also compared to the recommended conditions for emulsion formation. When forming an oil-in-water emulsion in an industrial process, it is recommended to choose an emulsifier which gives a phase inversion temperature (PIT) which is 20 - 60 o C higher than the actual temperature for use. The emulsification process must take place close to the PIT which is the temperature at which the emulsion change from oil-in-water emulsion to water-in-oil emulsion when the system is stirred. This condition corresponds to the temperature where the phase behavior change character. The purpose has been to find out if the composition of the dispersants corresponds to the recommendations for oil-in-water emulsification. The amount of experimental work has been limited. Two kinds of experiments have been carried out. Phase behavior studies have been done for seawater, bunker oil and four different dispersants where one had an optimal composition. The phase behavior was hard to interpret and is not recommended for standard dispersants test. The other experimental technique was PIT-measurements by conductivity measurements versus temperature. 4 figs., 1 tab., 4 refs

The effects of oil and dispersant on the blue mussel (Mytilus edulis L.) of the Quark region in the Gulf on Bothnia

International Nuclear Information System (INIS)

Lehtonen, K.

1989-01-01

The ecute toxic effects of heavy fuel oil (POR 180) and a dispersant (FinaSol OSR-5) were studied by static aquarium esposures, using the blue mussel (Mytilus edulis L.) as a test animal. The work was partially associated with the studies of the impact of the M/S Eira oil spill(1984) on the ecosystem of the Quark region in the Gulf of Bothnia. Test animals were collected from an area where the hydrologic condtions are very similar to those at the oil spill area. Different concentrations of oil and dispersant alone and their mixtures were used in the tests. Exposure time was 24 h, after which the animals were removed into clean water for a few weeks. Mortality and reduced byssal attachment ability were recorded as toxic effects. Surviving individuals were prepared for histological examination. POR 180's solubility into brackish water was poor. Test concentrations were not lethal to mussels, but the ability to attach was reduced in the highest concentrations. The 24 h LC 5 0-value for FinaSol OSR-5 was high (app. 2200 mg/l). The toxicity of oil/dispersant mixtures was high in the lower test concentrations. Histological examination revealed significant acute inflammatory reactions in the gastrointestinal track in some test groups

Conserving archaeological sites as biological and historical resources in the Gulf of Mexico: the effects of crude oil and dispersant on the biodiversity and corrosion potential of shipwreck bacterial biofilms

Science.gov (United States)

Salerno, J. L.; Little, B.; Lee, J.; Ray, R.; Hamdan, L. J.

2016-02-01

There are more than 2,000 documented shipwrecks in the Gulf of Mexico. Historic shipwrecks are invaluable cultural resources, but also serve as artificial reefs, enhancing biodiversity in the deep sea. Oil and gas-related activities have the potential to impact shipwreck sites. An estimated 30% of the oil from the Deepwater Horizon spill was deposited in the deep-sea, in areas that contain shipwrecks. We conducted field and laboratory experiments to determine if crude oil, dispersed oil, and/or dispersant affect the community composition, metabolic function, and/or corrosion potential of microorganisms inhabiting shipwrecks. Platforms containing carbon steel coupons (CSC) (n = 34 per platform) were placed at impacted and non-impacted shipwrecks or into four experimental microcosm tanks. After a 2-week acclimation period, tanks were treated with crude oil and/or dispersant or received no treatment. CSC and seawater (SW) samples for bacterial genetic analysis were collected bi-weekly (at 16 wks for field samples). Proteobacteria dominated field and lab CSC bacterial communities (77-97% of sequences). Field CSC bacterial communities differed at each wreck site (P = 0.001), with oil-impacted sites differing from control sites. Lab CSC bacterial communities differed between all treatment groups (P = 0.005) and changed over the course of the experiment (P = 0.001). CSC bacterial species richness, diversity, and dominance increased with time across all treatments indicating the recruitment and establishment of microbial biofilms on CSCs. SW bacterial communities differed between treatment groups (P = 0.001), with the dispersant treatment being most dissimilar from all other treatments (P < 0.01), and changed over time (P = 0.001). Oil- and oil/dispersant-treated CSCs exhibited higher corrosion compared to dispersant and control treatments. These findings indicate that exposure to oil and/or dispersant may alter bacterial community composition and corrosion potential.

The effects of crude oil and the effectiveness of cleaner application following oiling on US Gulf of Mexico coastal marsh plants.

Science.gov (United States)

Pezeshki, S R; DeLaune, R D; Jugsujinda, A

2001-01-01

Field studies were conducted in two different marsh habitats in Louisiana coastal wetlands to evaluate the effects of oiling (using South Louisiana Crude oil, SLC) and the effectiveness of a shoreline cleaner (COREXIT 9580) in removing oil from plant canopies. The study sites represented two major marsh habitats; the brackish marsh site was covered by Spartina patens and the freshwater marsh was covered by Sagittaria lancifolia. Field studies were conducted in each habitat using replicated 5.8 m2 plots that were subjected to three treatments; oiled only, oiled + cleaner (cleaner was used 2 days after oiling), and a control. Plant gas exchange responses, survival, growth, and biomass accumulation were measured. Results indicated that oiling led to rapid reductions in leaf gas exchange rates in both species. However, both species in 'oiled + cleaned' plots displayed improved leaf conductance and CO2 fixation rates. Twelve weeks after treatment initiation, photosynthetic carbon fixation in both species had recovered to normal levels. Over the short-term, S. patens showed more sensitivity to oiling with SLC than S. lancifolia as was evident from the data of the number of live shoots and above-ground biomass. Above-ground biomass remained significantly lower than control in S. patens under 'oiled' and 'oiled + cleaned' treatments while it was comparable to controls in S. lancifolia. These studies indicated that the cleaner removed oil from marsh grasses and alleviated the short-term impact of oil on gas exchange function of the study plants. However, use of cleaner had no detectable effects on above-ground biomass production or regeneration at the end of the first growing season in S. patens. Similarly, no beneficial effects of cleaner on carbon fixation and number of live shoots were apparent beyond 12 weeks in S. lancifolia.

Feasibility of using Ohmsett for dispersant testing and research

International Nuclear Information System (INIS)

Ross, S.L.; Buist, I.A.; Potter, S.G.; Belore, R.C.

2000-01-01

Laboratory dispersant testing proved to be of limited value for the prediction of actual dispersant effectiveness in spill situations. Variables such as oil type, weathered state, dispersant type, dispersant-to-oil ratio application method etc. were difficult to reproduce. A feasibility study was conducted at the Ohmsett facility in Leonardo, New Jersey to determine if the site was suitable for dispersant effectiveness testing. The study consisted of four phases: (1) interfacial tension laboratory tests, (2) turbidity tests, (3) the determination of the efficiency of filtering materials at the facility and alternative filtering materials, and (3) full-scale testing. Results indicated that dispersant in the water after the tests affected the interfacial tension of oils used in other tests following this one. Noticeable dispersion of floating oil occurred only after the concentration of dispersant in the water reached 400 ppm, making it possible to conduct consecutive experiments without having to worry about residual dispersant in the tank. The filtering of water to remove the dispersed oil was only required after several experiments had taken place on a given day. Evidently, it was only possible to have an underwater view of the dispersant testing during the first test of a series. The use of cellulose to aid the filtering at the facility removed most of the dispersed oil. The use of activated carbon resulted in a high degree of efficiency for the removal of dissolved dispersant. The testing of dispersant at Ohmsett proved possible as long as the design and implementation phases of the testing program respected the limitations stipulated above. 3 refs., 3 tabs., 3 figs

Discobiol program : investigation of dispersant use in coastal and estuarine waters

Energy Technology Data Exchange (ETDEWEB)

Merlin, F.X.; Le Floch, S.; Dussauze, M. [Cedre, Brest Cedex (France); Theron, M. [Brest Univ., European University of Britanny, Rennes (France); Quentel, C. [AFSSA, French Food Safety Agency, Paris (France); Thomas, H. [LIENS, CNRS-Univ. of La Rochelle, La Rochelle Cedex (France)

2009-07-01

This paper reported on the Discobiol work program designed to acquire comparable information on the impact of mechanically and chemically dispersed oil on different habitats and resources, particularly in estuaries or close to bays. The study involved 3 phases for the analysis of lethal and sub-lethal effects in pelagic and benthic communities, notably organisms in the water column, mudflats and salt marshes. The ultimate objective was to use the information to make recommendations regarding the use of dispersants in these 3 areas. Dispersants are known to be effective for offshore oil spill response when dilution conditions are high and dispersed oil concentrations decrease rapidly below levels that could harm the environment. However, dilution can be restricted in coastal areas, thus limiting the use of dispersant. All the tests conducted in this study were conducted using brut Arabian light oil that was pre-evaporated to simulate realistic conditions. The study examined whether the presence of oil leads to different effects than the control and whether the chemically dispersed oil gave different effects than the mechanical dispersion. The comparison with chemical dispersion in clear sea water examined whether the presence of suspended materials change the effect of the chemical dispersion. Results for the different phases of the project were presented. The preliminary results tend to open the use of chemical dispersion of oil slicks in coastal areas. The mixture of dispersant plus oil seems to be less detrimental than oil alone, particularly for turbot. The final conclusion regarding chemical dispersion of oil slicks in coastal areas will have to be formulated at the end of the project because coastal ecosystems depend on biotic and abiotic factors. The final phase will take place in a realistic environment in a salt marsh ecosystem at La Rochelle, France. 6 refs., 6 tabs., 6 figs.

Discobiol program : investigation of dispersant use in coastal and estuarine waters

International Nuclear Information System (INIS)

Merlin, F.X.; Le Floch, S.; Dussauze, M.; Theron, M.; Quentel, C.; Thomas, H.

2009-01-01

This paper reported on the Discobiol work program designed to acquire comparable information on the impact of mechanically and chemically dispersed oil on different habitats and resources, particularly in estuaries or close to bays. The study involved 3 phases for the analysis of lethal and sub-lethal effects in pelagic and benthic communities, notably organisms in the water column, mudflats and salt marshes. The ultimate objective was to use the information to make recommendations regarding the use of dispersants in these 3 areas. Dispersants are known to be effective for offshore oil spill response when dilution conditions are high and dispersed oil concentrations decrease rapidly below levels that could harm the environment. However, dilution can be restricted in coastal areas, thus limiting the use of dispersant. All the tests conducted in this study were conducted using brut Arabian light oil that was pre-evaporated to simulate realistic conditions. The study examined whether the presence of oil leads to different effects than the control and whether the chemically dispersed oil gave different effects than the mechanical dispersion. The comparison with chemical dispersion in clear sea water examined whether the presence of suspended materials change the effect of the chemical dispersion. Results for the different phases of the project were presented. The preliminary results tend to open the use of chemical dispersion of oil slicks in coastal areas. The mixture of dispersant plus oil seems to be less detrimental than oil alone, particularly for turbot. The final conclusion regarding chemical dispersion of oil slicks in coastal areas will have to be formulated at the end of the project because coastal ecosystems depend on biotic and abiotic factors. The final phase will take place in a realistic environment in a salt marsh ecosystem at La Rochelle, France. 6 refs., 6 tabs., 6 figs.

Toxicity of dispersant application: Biomarkers responses in gills of juvenile golden grey mullet (Liza aurata)

International Nuclear Information System (INIS)

Milinkovitch, Thomas; Godefroy, Joachim; Theron, Michael; Thomas-Guyon, Helene

2011-01-01

Dispersant use in nearshore areas is likely to increase the exposure of aquatic organisms to petroleum. To measure the toxicity of this controversial response technique, golden grey mullets (Liza aurata) were exposed to mechanically dispersed oil, chemically dispersed oil, dispersant alone in seawater, water-soluble fraction of oil and to seawater as a control treatment. Several biomarkers were assessed in the gills (enzymatic antioxidant activities, glutathione content, lipid peroxidation) and in the gallbladder (polycylic aromatic hydrocarbons metabolites). The significant differences between chemically dispersed oil and water soluble fraction of oil highlight the environmental risk to disperse an oil slick when containment and recovery can be conducted. The lack of significance between chemically and mechanically dispersed oil suggests that dispersant application is no more toxic than the natural dispersion of the oil slick. The results of this study are of interest in order to establish dispersant use policies in nearshore areas. - Highlights: → This study simulates and evaluates the toxicity of dispersant use in nearshore area. → Dispersant use toxicity is assessed through biomarkers measurement in a fish species. → Chemical dispersion of an oil slick increases the petroleum toxicity. → Dispersant use does not enhance the toxicity of a mechanically dispersed oil slick. → This work leads to conclusions concerning dispersant use policies in nearshore area. - When the meteorological conditions induce the dispersion of the oil slick (e.g. wave), the application of dispersant does not increase the toxicity of petroleum.

Research on using oil herding surfactants to thicken oil slicks in pack ice for in situ burning

International Nuclear Information System (INIS)

Buist, I.; Morrison, J.

2005-01-01

The severe limitations of conventional containment and recovery systems for oil spills in pack ice have been demonstrated during skimmer tests conducted in the Alaskan Beaufort Sea. In-situ burning may be one of the few viable alternatives to quickly remove oil spilled in pack ice, but the slicks are often too thin, preventing effective ignition or burning. This study examined ways to thicken the slicks to the 2- to 5-mm range so that effective burns could be carried out. Specific chemical surface-active agents known as oil herders or oil collecting agents can be used to clear and contain oil slicks on water surfaces. Since these agents can spread quickly on water, only a small quantity is needed to clear thin films of oil from large areas of water. Applying a chemical herder around the periphery of spilled oil can contract the oil into a thicker slick. Two chemical products were developed and tested in the 1970s and 1980s: Shell Herder and Exxon OC-5 Oil Collector. However, they are no longer used because they were effective only in very calm conditions. Corexit EC9580 which exhibits similar slick herding abilities and which has a spreading pressure of 39.5 mN/m is still commercially available. This study tested formulations of herding agents for use in pack ice. Concerns regarding the potential toxicity risk of using these agents in pack ice were also addressed. The agents should not harm the environment because they have low toxicity and only very small quantities are used. Two series of tests conducted to assess the potential for herding agents to help ignite and effectively burn thin oil slicks in loose pack ice conditions. The agents proved to be effective on cold water and on thick slicks. The composition of the oil played an important role in determining potential efficiency. It was concluded that applying herders to thin oil slicks in pack ice shows considerable promise for thickening them for in-situ burning. 12 refs., 4 tabs., 17 figs

Studies of emulsification, emulsion prevention and underwater dispersion

Energy Technology Data Exchange (ETDEWEB)

Celius, H.K.; Vassbotn, T.

1985-03-01

This is a report from the work performed under task 2: ''Effect of demulsifiers and despersants injected into a blowing oil stream'' of the research program ''Dispersion of oil on sea''. Three ad hoc experiments have been carried out involving laboratory studies in a small turbulent oil plume, tests with revolving flasks, and a small scale field test with a combined gas/oil plume. The results show that emulsion is formed in plume from underwater blowouts, and that this formation is prevented by small amounts (250 ppM) of demulsifiers or dispersants. Larger concentrations of dispersants (ca 2%) disperse the oil, and the oil is transported to the upper water layer in the gas/oil plume. None of the experiments have been designed as true scale tests, and the results cannot be directly transferred to operational, full scale conditions. The experiments have however narroved the necessary extent of studies, and allows for a simpler experimental procedure in the full scale field test planned for June 1985. 19 references.

Soybean-oil-based waterborne polyurethane dispersions: effects of polyol functionality and hard segment content on properties.

Science.gov (United States)

Lu, Yongshang; Larock, Richard C

2008-11-01

The environmentally friendly vegetable-oil-based waterborne polyurethane dispersions with very promising properties have been successfully synthesized without difficulty from a series of methoxylated soybean oil polyols (MSOLs) with different hydroxyl functionalities ranging from 2.4 to as high as 4.0. The resulting soybean-oil-based waterborne polyurethane (SPU) dispersions exhibit a uniform particle size, which increases from about 12 to 130 nm diameter with an increase in the OH functionality of the MSOL from 2.4 to 4.0 and decreases with increasing content of the hard segments. The structure and thermophysical and mechanical properties of the resulting SPU films, which contain 50-60 wt % MSOL as renewable resources, have been studied by Fourier transform infrared spectroscopy, differential scanning calorimetry, dynamic mechanical analysis, thermogravimetric analysis, transmission electron microscopy, and mechanical testing. The experimental results reveal that the functionality of the MSOLs and the hard segment content play a key role in controlling the structure and the thermophysical and mechanical properties of the SPU films. These novel films exhibit tensile stress-strain behavior ranging from elastomeric polymers to rigid plastics and possess Young's moduli ranging from 8 to 720 MPa, ultimate tensile strengths ranging from 4.2 to 21.5 MPa, and percent elongation at break values ranging from 16 to 280%. This work has addressed concerns regarding gelation and higher cross-linking caused by the high functionality of vegetable-oil-based polyols. This article reports novel environmentally friendly biobased SPU materials with promising applications as decorative and protective coatings.

Synthesis of colloids based on gold nanoparticles dispersed in castor oil

International Nuclear Information System (INIS)

Silva, E. C. da; Silva, M. G. A. da; Meneghetti, S. M. P.; Machado, G.; Alencar, M. A. R. C.; Hickmann, J. M.; Meneghetti, M. R.

2008-01-01

New colloidal solutions of gold nanoparticles (AuNP), using castor oil as a nontoxic organic dispersant agent, were prepared via three different methods. In all three cases, tetrachloroauric(III) acid was employed as the gold source. The colloids were characterized by UV-Vis spectroscopy and transmission electron microscopy (TEM). The AuNP produced by the three methods were quasispherical in shape, however with different average sizes. The individual characteristics of the nanoparticles presented in each colloidal system were also confirmed by observation of absorption maxima at different wavelengths of visible light. Each method of synthesis leads to colloids with different grades of stability with respect to particle agglomeration.

Toxicity of dispersant application: Biomarkers responses in gills of juvenile golden grey mullet (Liza aurata).

Science.gov (United States)

Milinkovitch, Thomas; Godefroy, Joachim; Théron, Michaël; Thomas-Guyon, Hélène

2011-10-01

Dispersant use in nearshore areas is likely to increase the exposure of aquatic organisms to petroleum. To measure the toxicity of this controversial response technique, golden grey mullets (Liza aurata) were exposed to mechanically dispersed oil, chemically dispersed oil, dispersant alone in seawater, water-soluble fraction of oil and to seawater as a control treatment. Several biomarkers were assessed in the gills (enzymatic antioxidant activities, glutathione content, lipid peroxidation) and in the gallbladder (polycylic aromatic hydrocarbons metabolites). The significant differences between chemically dispersed oil and water soluble fraction of oil highlight the environmental risk to disperse an oil slick when containment and recovery can be conducted. The lack of significance between chemically and mechanically dispersed oil suggests that dispersant application is no more toxic than the natural dispersion of the oil slick. The results of this study are of interest in order to establish dispersant use policies in nearshore areas. Copyright © 2011 Elsevier Ltd. All rights reserved.

Grand LAgrangian Deployment (GLAD): Surface Dispersion Characteristics Near the Deepwater Horizon Oil Spill Site

Science.gov (United States)

Ozgokmen, Tamay; Poje, Andrew; Lipphardt, Bruce, Jr.; Haza, Angelique; Haus, Brian; Jacobs, Gregg; Reniers, Ad; Olascoaga, Josefina; Ryan, Edward; Novelli, Guillaume; Kirwan, Albert, Jr.; Griffa, Annalisa; Chen, Shuyi; Hogan, Pat

2013-04-01

Initial dispersion, residence time, and advective pathway results obtained from the nearly simultaneous deployment of some 300 surface drifters in the vicinity of the DwH oil spill in the DeSoto Canyon are reported. The goal of the GLAD experiment was to characterize, with unprecedented statistical significance, multi-point and multi-scale dispersion properties of the flow in the region of the DwH spill site including demarcation of the advective pathways between the Canyon and larger-scale flow features in the Gulf. Both the absolute and relative dispersion of surface drifters was quite slow for those drifters initialized within the Missippippi River Outflow. For the initial time period considered, drifter motion was characterized by large amplitude inertial motions, overall strong topographic control, and significant indications of interior control by frontal dynamics on 1-5 km scales. Very limited exchange, either across-shelf or with nearby mesoscale features, was observed and residence times in the Canyon typically exceeded one week with many drifters remaining there for more than 21 days.

Membranes as separators of dispersed emulsion phases

NARCIS (Netherlands)

Lefferts, A.G.

1997-01-01

The reuse or discharge of industrial waste waters, containing small fractions of dispersed oil, requires a purification treatment for which membranes can be used. If only little oil is present, removal of the dispersed phase might be preferable to the more commonly applied removal of the

Aquatic toxicity of petroleum products and dispersant agents determined under the U.S. EPA Oil Spill Research Program

Science.gov (United States)

The U.S. EPA Office of Research and Development has developed baseline data on the ecotoxicity of selected petroleum products and several chemical dispersants as part of its oil spills research program. Two diluted bitumens (dilbits) from the Alberta Tar Sands were tested for acu...

Shoreline clean up during the Sea Empress incident: the role of surf washing (clay-oil flocculation), dispersants and bioremediation

International Nuclear Information System (INIS)

Lunel, T.; Lee, K.

1996-01-01

An outline of the at sea operations which took place in response to the Sea Empress oil spill, was presented. The grounding of the Sea Empress resulted in the release of 70,000 tonnes of blended crude oil into the environment. A qualitative account of the events which followed the incident were described. The early mobilization of a monitoring team has demonstrated the importance of scientific measurements to identify and maximize the efficiency of various cleanup operations. One of the important responses to this incident was the application of dispersants which by inducing flocculation, thereby reducing contact of oil directly with the substrate, and by reducing adhesion of the oil to the shoreline, contributed greatly to minimizing shoreline impact. 19 refs., 7 figs

Membranes as separators of dispersed emulsion phases

OpenAIRE

Lefferts, A.G.

1997-01-01

The reuse or discharge of industrial waste waters, containing small fractions of dispersed oil, requires a purification treatment for which membranes can be used. If only little oil is present, removal of the dispersed phase might be preferable to the more commonly applied removal of the continuous phase. For this purpose dispersed phase separators can be applied, which combine the features of conventional coalescers and membrane filtration. The membrane surface promotes coalescence ...

Effects of oil and chemically treated oil on nearshore under-ice meiofauna studied in-situ

Energy Technology Data Exchange (ETDEWEB)

Cross, W.E.; Martin, C.M.

1987-01-01

Meiofauna were collected during May 1982 in the soft bottom layer of nearshore landfast ice at Cape Hatt, northern Baffin Island. Average abundance of all ice meiofauna was 54,000 individualsm/sup -2/. Densities of all meiofauna groups were spatially variable, but only nematodes and cyclopoid copepods showed evidence of progressive temporal change between 18 May and 2 June. Undisturbed, enclosed areas of the under-ice surface were treated with oil on 23-24 May. Dispersed oil was in contact with the ice for 5 hours, whereas untreated oil and solidified oil remained in the enclosures for the duration of the study (12 days post-treatment). Sampling was carried out in areas where oil contacted the ice and moved away or in areas near oil that remained in contact with the under-ice surface. Five hours after treatment, oil concentrations in the water within the enclosures were similar (0.15-0.28 ppm) in untreated oil, solidified oil and control enclosures. In contrast, dispersed oil concentrations were 5.8-36.5 ppm. Densities of all copepods and polychaetes decreased dramatically in each dispersed oil enclosure by the second post-spill day, and slight density increases were evident by the tenth post-spill day. Harpacticoid copepods apparently were more sensitive to dispersed oil than were cyclopoid copepods. Densities of nematodes and cyclopoid copepod nauplii were not affected by dispersed oil. Densities of nematodes, polychaetes and all copepods were not affected by untreated or solidified oil, but there was some evidence of a stimulatory effect of those treatments on some copepod groups and life stages. 24 refs., 2 figs., 4 tabs.

Choice of test organisms for determination of oil dispersant toxicity in marine waters. Auswahl von Testorganismen zur Bestimmung der Toxizitaet von Dispergatoren bei der Oelbekaempfung in marinen Gewaessern

Energy Technology Data Exchange (ETDEWEB)

Henke, G.A.

1987-06-01

Several marine organisms were investigated regarding their qualification for oil dispersant toxicity determination. Appropriate organisms were chosen for two different test procedures: Using mortality as a test criterion an acute toxicity test can be carried out very easy with larvae of the brine shrimp Artemia sp. The sensitivity for different dispersants ranges over several orders of magnitude. Another test indicator is the cell multiplication-inhibition test, conducted with the microalga Scrippsiella trochoidea, a representative of phytoplankton. The sensitivity for a common dispersant ranges a hundredfold higher than the acute toxicity test. Both test procedures are also practicable for other water-soluble substances, as well. One oil-spill dispersant efficiency test is proposed provisionally. (orig.) With 62 refs., 20 tabs., 11 figs.

Evaluation of ensemble atmospheric simulations in oil dispersion models at Itaguai Port region; Avaliacao do uso de resultados numericos de previsao atmosferica por conjunto na modelagem da dispersao de oleo na regiao do Porto de Itaguai

Energy Technology Data Exchange (ETDEWEB)

Santos, Renato Goncalves dos; Silva, Mariana P.R.; Silva, Ricardo Marcelo da; Torres Junior, Audalio R. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Lab. de Modelagem de Processos Marinhos e Atmosfericos (LAMMA); Landau, Luiz [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Lab. de Metodos Computacinais em Engenharia (LAMCE); Sa, Reginaldo Ventura de; Hochleitner, Fabio; Correa, Eduardo Barbosa [AQUAMET Meteorologia e Projeto de Sistemas, Rio de Janeiro, RJ (Brazil)

2008-07-01

This work discusses the use of numerical prediction using ensemble as boundary condition in pollutants dispersion models, applied in a hypothetical case of an oil spill occurrence in Itaguai Port. The Princeton Ocean Model (POM) has been used to simulate hydrodynamics and NICOIL Eulerian model to forecast oil spill dispersion, and ensemble wind forecast from Global Forecast System (GFS), aiming to assess the importance of this parameter variability in oil dispersion at sea. The wind scenarios using ensemble members has showed significant dispersion when compared to control simulation, demonstrating that the uncertainty in the atmospheric modeling can generate considerable variations in the placement of the final spot of oil. The region of interest was the Sepetiba Bay, located on the southern coast of the Rio de Janeiro state; because of port operations carried out around the Port of Itaguai where they can, eventually, oil leaks occur. (author)

Ferrofluid synthesis using oleic acid coated Fe3O4 nanoparticles dispersed in mineral oil for heat transfer applications

Science.gov (United States)

Imran, Mohd; Rahman Ansari, Akhalakur; Hussain Shaik, Aabid; Abdulaziz; Hussain, Shahir; Khan, Afzal; Rehaan Chandan, Mohammed

2018-03-01

Ferrofluids are stable dispersion of iron oxide nanoparticles in a carrier fluid which find potential applications in heat transfer. Fe3O4 nanoparticles of mean size in the range of 5–10 nm were synthesized using conventional co-precipitation method. This work deals with the synthesis of ferrofluids using mineral oil as a carrier fluid and oleic acid coated Fe3O4 nanoparticles as dispersed phase. Morphology (shape and size) and crystallinity of the synthesized nanoparticle is captured using TEM and XRD. Oleic acid coating on nanoparticle is probed using FTIR for confirming the stability of ferrofluid. Thermal properties of mineral oil based ferrofluid with varying concentration of nanoparticles are evaluated in terms of thermal conductivity. It was found that the thermal conductivity of ferrofluid increases upto 2.5% (w/v) nanoparticle loading, where a maximum enhancement of ∼51% in thermal conductivity was recorded as compared to the base fluid.

Dispersant testing : a study on analytical test procedures

International Nuclear Information System (INIS)

Fingas, M.F.; Fieldhouse, B.; Wang, Z.; Environment Canada, Ottawa, ON

2004-01-01

Crude oil is a complex mixture of hydrocarbons, ranging from small, volatile compounds to very large, non-volatile compounds. Analysis of the dispersed oil is crucial. This paper described Environment Canada's ongoing studies on various traits of dispersants. In particular, it describes small studies related to dispersant effectiveness and methods to improve analytical procedures. The study also re-evaluated the analytical procedure for the Swirling Flask Test, which is now part of the ASTM standard procedure. There are new and improved methods for analyzing oil-in-water using gas chromatography (GC). The methods could be further enhanced by integrating the entire chromatogram rather than just peaks. This would result in a decrease in maximum variation from 5 per cent to about 2 per cent. For oil-dispersant studies, the surfactant-dispersed oil hydrocarbons consist of two parts: GC-resolved hydrocarbons and GC-unresolved hydrocarbons. This study also tested a second feature of the Swirling Flask Test in which the side spout was tested and compared with a new vessel with a septum port instead of a side spout. This decreased the variability as well as the energy and mixing in the vessel. Rather than being a variation of the Swirling Flask Test, it was suggested that a spoutless vessel might be considered as a completely separate test. 7 refs., 2 tabs., 4 figs

40 CFR Appendix C to Part 300 - Swirling Flask Dispersant Effectiveness Test, Revised Standard Dispersant Toxicity Test, and...

Science.gov (United States)

2010-07-01

... the test oil (i.e., a dispersant-to-oil ratio of 1:10). This ratio is used in the test tank with... minutes for oil droplet “settling.” 7. At the conclusion of the 10-minute settling period, carefully...

Determination of solvent concentration-dependent dispersion in the vapor extraction (VAPEX) process

Energy Technology Data Exchange (ETDEWEB)

Abukhalifeh, H.; Lohi, A.; Upreti, S. [Ryerson Polytechnic Univ., Toronto, ON (Canada)

2008-07-01

This paper presented the results of a computational algorithm that revealed the optimal conditions required for vapor extraction (VAPEX) for a solvent gas-heavy oil system. VAPEX is a promising recovery process because it requires low energy use and emits fewer greenhouse gases to the atmosphere compared to other enhanced oil recovery methods. The process is governed by the dispersion of solvent gases into heavy oil and bitumen. As such, it is essential to accurately determine solvent dispersion in VAPEX in order to effectively predict the amount and time scale of oil recovery, and to optimize field operations. VAPEX experiments were conducted in this study to determined the dispersion coefficient of a solvent as a function of its concentration in heavy oil and bitumen. The principles of variational calculus were used together with a mass transfer model of the experimental process. It was concluded that the oil production determined by the model should agree with its experimental counterpart, given the optimal gas dispersion versus concentration function.

Hydrodeoxygenation of water-insoluble bio-oil to alkanes using a highly dispersed Pd-Mo catalyst.

Science.gov (United States)

Duan, Haohong; Dong, Juncai; Gu, Xianrui; Peng, Yung-Kang; Chen, Wenxing; Issariyakul, Titipong; Myers, William K; Li, Meng-Jung; Yi, Ni; Kilpatrick, Alexander F R; Wang, Yu; Zheng, Xusheng; Ji, Shufang; Wang, Qian; Feng, Junting; Chen, Dongliang; Li, Yadong; Buffet, Jean-Charles; Liu, Haichao; Tsang, Shik Chi Edman; O'Hare, Dermot

2017-09-19

Bio-oil, produced by the destructive distillation of cheap and renewable lignocellulosic biomass, contains high energy density oligomers in the water-insoluble fraction that can be utilized for diesel and valuable fine chemicals productions. Here, we show an efficient hydrodeoxygenation catalyst that combines highly dispersed palladium and ultrafine molybdenum phosphate nanoparticles on silica. Using phenol as a model substrate this catalyst is 100% effective and 97.5% selective for hydrodeoxygenation to cyclohexane under mild conditions in a batch reaction; this catalyst also demonstrates regeneration ability in long-term continuous flow tests. Detailed investigations into the nature of the catalyst show that it combines hydrogenation activity of Pd and high density of both Brønsted and Lewis acid sites; we believe these are key features for efficient catalytic hydrodeoxygenation behavior. Using a wood and bark-derived feedstock, this catalyst performs hydrodeoxygenation of lignin, cellulose, and hemicellulose-derived oligomers into liquid alkanes with high efficiency and yield.Bio-oil is a potential major source of renewable fuels and chemicals. Here, the authors report a palladium-molybdenum mixed catalyst for the selective hydrodeoxygenation of water-insoluble bio-oil to mixtures of alkanes with high carbon yield.

A novel technique to determine concentration-dependent solvent dispersion in Vapex

Energy Technology Data Exchange (ETDEWEB)

Abukhalifeh, H.; Lohi, A.; Upreti, S. R. [Department of Chemical Engineering, Ryerson University, 350 Victoria Street, Toronto, Ontario, M5B 2K3 (Canada)

2009-07-01

Vapex (vapor extraction of heavy oil and bitumen) is a promising recovery technology because it consumes low energy, and is very environmentally-friendly. The dispersion of solvents into heavy oil and bitumen is a crucial transport property governing Vapex. The accurate determination of solvent dispersion in Vapex is essential to effectively predict the amount and time scale of oil recovery as well to optimize the field operations. In this work, a novel technique is developed to experimentally determine the concentration-dependent dispersion coefficient of a solvent in Vapex process. The principles of variational calculus are utilized in conjunction with a mass transfer model of the experimental Vapex process. A computational algorithm is developed to optimally compute solvent dispersion as a function of its concentration in heavy oil. The developed technique is applied to Vapex utilizing propane as a solvent. The results show that dispersion of propane is a unimodal function of its concentration in bitumen. (author)

A Novel Technique to Determine Concentration-Dependent Solvent Dispersion in Vapex

Directory of Open Access Journals (Sweden)

Hadil Abukhalifeh

2009-10-01

Full Text Available Vapex (vapor extraction of heavy oil and bitumen is a promising recovery technology because it consumes low energy, and is very environmentally-friendly. The dispersion of solvents into heavy oil and bitumen is a crucial transport property governing Vapex. The accurate determination of solvent dispersion in Vapex is essential to effectively predict the amount and time scale of oil recovery as well to optimize the field operations. In this work, a novel technique is developed to experimentally determine the concentration-dependent dispersion coefficient of a solvent in Vapex process. The principles of variational calculus are utilized in conjunction with a mass transfer model of the experimental Vapex process. A computational algorithm is developed to optimally compute solvent dispersion as a function of its concentration in heavy oil. The developed technique is applied to Vapex utilizing propane as a solvent. The results show that dispersion of propane is a unimodal function of its concentration in bitumen.

Dispersant Effectiveness, In-Situ Droplet Size Distribution and ...

Science.gov (United States)

This report summarizes two projects covered under an Interagency Agreement between the Bureau of Safety and Environmental Enforcement (BSEE) and the U.S. Environmental Protection Agency (EPA) in collaboration with the Bedford Institute of Oceanography, Department of Fisheries and Oceans Canada (BIO DFO), New Jersey Institute of Technology (NJIT) and Dalhousie University. Both projects dovetail together in addressing the ability to differentiate physical from chemical dispersion effectiveness using dispersed oil simulations within a flume tank for improving forensic response monitoring tools. This report is split into separateTasks based upon the two projects funded by BSEE: 1) Dispersant Effectiveness, In-Situ Droplet Size Distribution and Numerical Modeling to Assess Subsurface Dispersant Injection as a Deepwater Blowout Oil Spill Response Option. 2) Evaluation of Oil Fluorescence Characteristics to Improve Forensic Response Tools. This report summarizes 2 collaborative projects funded through an Interagency Agreement with DOI BSEE and a Cooperative Agreement with DFO Canada. BSEE required that the projects be combined into one report as they are both covered under the one Interagency Agreement. Task B (Fluorescence of oils) is an SHC 3.62 FY16 product.

Influence of dispersants on petroleum bioavailability in a marine food chain

International Nuclear Information System (INIS)

Wolfe, M.; Tjeerdema, R.

1995-01-01

When crude oil is accidentally released into the ocean it threatens many levels of marine life. Intervention, in the form of chemical dispersing agents, may alter the normal behavior of petroleum hydrocarbons (PH) by increasing their functional water solubility and the extent of their exposure to sub-surface marine organisms. Further, the dispersing agent may modify bioavailability as a result of altered interactions between dispersed PH droplets and organismal cell membranes, To date, little information exists on the sub-lethal effects of dispersants and factors modifying their role in the bioavailability and disposition of PH in marine food chains. The objective of the current research was to determine the impact of dispersing agents on PH bioavailability to primary levels of a marine food chain. Uptake, bioaccumulation, deputation, and metabolic transformation of a model PH, 14 C-naphthalene, were measured and compared for dispersed Prudhoe Bay Crude Oil (PBCO) vs. undispersed preparations of the water-accommodated fractions (WAF) of PBCO at two salinities (22 and 34 ppt) employing Isochrysis galbana, a primary producer, and Brachionus plicatilis, a primary consumer. Fractionation and identification of metabolites was done by HPLC co-chromatography with analytical standards, and quantitation was done by liquid scintillation counting. GC-FID characterization of WAF and dispersed oil preparations shows higher concentrations of petroleum hydrocarbons and a greater number of individual constituents in the dispersed oil preparations. However, short term (eight hour) and long term (two week) static exposure studies indicate the uptake of 14 C-naphthalene from WAF preparations is inhibited by up to 50% from dispersed oil preparations. Results of comparative static and flow-through chamber exposure studies will be presented

Influence of dispersants on petroleum bioavailability in a marine food chain

Energy Technology Data Exchange (ETDEWEB)

Wolfe, M.; Tjeerdema, R. [Univ. of California, Santa Cruz, CA (United States). Dept. of Chemistry and Biochemistry; Sowby, M. [California Dept. of Fish and Game, Sacramento, CA (United States)

1995-12-31

When crude oil is accidentally released into the ocean it threatens many levels of marine life. Intervention, in the form of chemical dispersing agents, may alter the normal behavior of petroleum hydrocarbons (PH) by increasing their functional water solubility and the extent of their exposure to sub-surface marine organisms. Further, the dispersing agent may modify bioavailability as a result of altered interactions between dispersed PH droplets and organismal cell membranes, To date, little information exists on the sub-lethal effects of dispersants and factors modifying their role in the bioavailability and disposition of PH in marine food chains. The objective of the current research was to determine the impact of dispersing agents on PH bioavailability to primary levels of a marine food chain. Uptake, bioaccumulation, deputation, and metabolic transformation of a model PH, {sup 14}C-naphthalene, were measured and compared for dispersed Prudhoe Bay Crude Oil (PBCO) vs. undispersed preparations of the water-accommodated fractions (WAF) of PBCO at two salinities (22 and 34 ppt) employing Isochrysis galbana, a primary producer, and Brachionus plicatilis, a primary consumer. Fractionation and identification of metabolites was done by HPLC co-chromatography with analytical standards, and quantitation was done by liquid scintillation counting. GC-FID characterization of WAF and dispersed oil preparations shows higher concentrations of petroleum hydrocarbons and a greater number of individual constituents in the dispersed oil preparations. However, short term (eight hour) and long term (two week) static exposure studies indicate the uptake of{sup 14}C-naphthalene from WAF preparations is inhibited by up to 50% from dispersed oil preparations. Results of comparative static and flow-through chamber exposure studies will be presented.

Vegetable oil spills : oil properties and behaviour

International Nuclear Information System (INIS)

Fingas, M.; Fieldhouse, B.; Jokuty, P.

2001-01-01

In 1997, the United States Environmental Protection Agency conducted a thorough review of the issue regarding vegetable oil spills. Recent attention has refocused on this issue as a result of an incident where 20 tons of canola oil was spilled in the Vancouver Harbour in 2000. In the past, vegetable oils were suggested to be a useful test material because they were thought to be innocuous. It was even suggested they be used to remove petroleum oil residues from beaches. However, recent studies have shown that spills of vegetable oils can have major environmental consequences, equivalent to those of petroleum oil spills. The spills have devastating effects on birds and intertidal organisms. This paper presented a summary of historical vegetable spills from around the world. In this study, specific behaviour tests were examined for several oils including canola, soy bean, olive, castor and corn oils. Evaporation, water-in-oil emulsification and chemical dispersion were measured and were found to be nearly zero, suggesting that vegetable oil spills are not very soluble in water. The aquatic toxicity of vegetable oil is low, but their fate is quite different from petroleum. Vegetable oils do not evaporate to a significant degree, they do not form water-in-oil emulsions, nor do they disperse in water. The physical properties of vegetable oils were also measured, including density and viscosity. This paper presented the aquatic toxicity of several vegetable oils along with other environmental data including the degradation rates noted in the literature. Most environmental damage reported in the literature is by contact with birds feathers resulting in hypothermia and secondly by smothering of intertidal organisms. The effect of vegetable oil on fish has not been well studied, but it is expected that there will be little destructive effect except where smothering can occur. 35 refs., 3 tabs

Vegetable oil spills : oil properties and behaviour

Energy Technology Data Exchange (ETDEWEB)

Fingas, M.; Fieldhouse, B.; Jokuty, P. [Environment Canada, Ottawa, ON (Canada). Emergencies Science Div

2001-07-01

In 1997, the United States Environmental Protection Agency conducted a thorough review of the issue regarding vegetable oil spills. Recent attention has refocused on this issue as a result of an incident where 20 tons of canola oil was spilled in the Vancouver Harbour in 2000. In the past, vegetable oils were suggested to be a useful test material because they were thought to be innocuous. It was even suggested they be used to remove petroleum oil residues from beaches. However, recent studies have shown that spills of vegetable oils can have major environmental consequences, equivalent to those of petroleum oil spills. The spills have devastating effects on birds and intertidal organisms. This paper presented a summary of historical vegetable spills from around the world. In this study, specific behaviour tests were examined for several oils including canola, soy bean, olive, castor and corn oils. Evaporation, water-in-oil emulsification and chemical dispersion were measured and were found to be nearly zero, suggesting that vegetable oil spills are not very soluble in water. The aquatic toxicity of vegetable oil is low, but their fate is quite different from petroleum. Vegetable oils do not evaporate to a significant degree, they do not form water-in-oil emulsions, nor do they disperse in water. The physical properties of vegetable oils were also measured, including density and viscosity. This paper presented the aquatic toxicity of several vegetable oils along with other environmental data including the degradation rates noted in the literature. Most environmental damage reported in the literature is by contact with birds feathers resulting in hypothermia and secondly by smothering of intertidal organisms. The effect of vegetable oil on fish has not been well studied, but it is expected that there will be little destructive effect except where smothering can occur. 35 refs., 3 tabs.

Improved new generation dispersants

International Nuclear Information System (INIS)

Anon.

1993-01-01

The use of dispersants to combat oil spills has attracted controversy over the years, and there has been a number of accusations of the chemicals involved doing more harm than good. A new study by the International Petroleum Industry Environmental Conservation Association discusses the positive and the negatives of dispersant use to be considered when drawing up spill contingency plans. (author)

About Ganoderma boninense in oil palm plantations of Sumatra and peninsular Malaysia: Ancient population expansion, extensive gene flow and large scale dispersion ability.

Science.gov (United States)

Mercière, Maxime; Boulord, Romain; Carasco-Lacombe, Catherine; Klopp, Christophe; Lee, Yang-Ping; Tan, Joon-Sheong; Syed Alwee, Sharifah S R; Zaremski, Alba; De Franqueville, Hubert; Breton, Frédéric; Camus-Kulandaivelu, Létizia

Wood rot fungi form one of the main classes of phytopathogenic fungus. The group includes many species, but has remained poorly studied. Many species belonging to the Ganoderma genus are well known for causing decay in a wide range of tree species around the world. Ganoderma boninense, causal agent of oil palm basal stem rot, is responsible for considerable yield losses in Southeast Asian oil palm plantations. In a large-scale sampling operation, 357 sporophores were collected from oil palm plantations spread over peninsular Malaysia and Sumatra and genotyped using 11 SSR markers. The genotyping of these samples made it possible to investigate the population structure and demographic history of G. boninense across the oldest known area of interaction between oil palm and G. boninense. Results show that G. boninense possesses a high degree of genetic diversity and no detectable genetic structure at the scale of Sumatra and peninsular Malaysia. The fact that few duplicate genotypes were found in several studies including this one supports the hypothesis of spore dispersal in the spread of G. boninense. Meanwhile, spatial autocorrelation analysis shows that G. boninense is able to disperse across both short and long distances. These results bring new insight into mechanisms by which G. boninense spreads in oil palm plantations. Finally, the use of approximate Bayesian computation (ABC) modelling indicates that G. boninense has undergone a demographic expansion in the past, probably before the oil palm was introduced into Southeast Asia. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Air Pollution Dispersion Modeling of Abadan oil Refinery Using SCREEN3

International Nuclear Information System (INIS)

Hedayati Rad, F.; Salman-Mahini, A.; Mirkarimi, H.

2016-01-01

Air pollution is a major problem that has been recognized throughout the world. Refineriers normally create environmental pollution through emissions of pollutants gaseous from a variety of sources. Analysing air pollution distribution and dispersion can help in reducing the negative effects. In this study NO_X and SO_2 emissions and distributions were investigated for Abadan oil refinery using SCREEN3 software. In this softweare, wind speed and direction, air temperature, location and physical characteristics of chimnies and atmospheric stability were taken into consideration.The concentration of pollutants in different distances from the stacks in the range 25 km were predicted and mapped in Idrisi software. The output from software SCREEN3 for emissions from stacks were also examined and compared with the standard output of the refineries. According to our results, the concentration of pollutants in summer and autumn seasons exceeds of the environmental standards.

Comparative Risk Assessment of spill response options for a deepwater oil well blowout: Part 1. Oil spill modeling.

Science.gov (United States)

French-McCay, Deborah; Crowley, Deborah; Rowe, Jill J; Bock, Michael; Robinson, Hilary; Wenning, Richard; Walker, Ann Hayward; Joeckel, John; Nedwed, Tim J; Parkerton, Thomas F

2018-05-31

Oil spill model simulations of a deepwater blowout in the Gulf of Mexico De Soto Canyon, assuming no intervention and various response options (i.e., subsea dispersant injection SSDI, in addition to mechanical recovery, in-situ burning, and surface dispersant application) were compared. Predicted oil fate, amount and area of surfaced oil, and exposure concentrations in the water column above potential effects thresholds were used as inputs to a Comparative Risk Assessment to identify response strategies that minimize long-term impacts. SSDI reduced human and wildlife exposure to volatile organic compounds; dispersed oil into a large water volume at depth; enhanced biodegradation; and reduced surface water, nearshore and shoreline exposure to floating oil and entrained/dissolved oil in the upper water column. Tradeoffs included increased oil exposures at depth. However, since organisms are less abundant below 200 m, results indicate that overall exposure of valued ecosystem components was minimized by use of SSDI. Copyright © 2018 Elsevier Ltd. All rights reserved.

Evaluating Chemical Dispersant Efficacy In An Experimental Wave Tank: 1, Dispersant Effectiveness As A Function Of Energy Dissipation Rate

Science.gov (United States)

Numerous laboratory test systems have been developed for the comparison of efficacy between various chemical oil dispersant formulations. However, for the assessment of chemical dispersant effectiveness under realistic sea state, test protocols are required to produce hydrodynam...

Factors in the dispersant use decision-making process : historical overview and look to the future

International Nuclear Information System (INIS)

Etkin, D.S.

1998-01-01

The history of chemical dispersant use in response to marine oil spills was reviewed. A series of case histories were presented to show the political, technical, and financial issues that have influenced the decision-making process and which are likely to influence dispersant use in the future. It was shown that response coordinators must consider the potential effectiveness of dispersant treatment and also the potential for environmental benefit or environmental damage. The safety and effectiveness of dispersant use were shown to depend on: (1) the type of oil or product spilled, (2) the amount of oil spilled, (3) the proximity to the shore and to sensitive habitats, (4) the weather and sea conditions at the time of the spill and during the response, (5) the types of dispersant chemicals on the market at the time of the spill, and (6) the potential efficiency of other cleanup methodologies available. It was noted that more than 37 per cent of the marine oil spills recorded in the Oil Spill Intelligence Report's international oil spill database involve the use of dispersants during the cleanup operations. 21 refs., 4 tabs

Preparation of Microcapsules Containing β-Carotene with Thermo Sensitive Curdlan by Utilizing Reverse Dispersion

Directory of Open Access Journals (Sweden)

Yoshinari Taguchi

2013-11-01

Full Text Available We have tried to microencapsulate β-carotene with curdlan of a thermogelation type polysaccharide. Microcapsules were prepared by utilizing reverse dispersion, in which salada oil was the continuous phase (O’ and the curdlan water slurry (W was the dispersed phase. β-carotene (O as a core material was broken into fine oil droplets in the dispersed phase to form the (O/W dispersion. The (O/W dispersion was poured in the continuous phase (O’ and stirred to form the (O/W/O’ dispersion at room temperature and then, temperature of the dispersion was raised to 80 °C to prepare curdlan-microcapusles containing β-carotene. In this microencapsulation process, the concentrations of curdlan and oil soluble surfactant and the impeller speed to form the (O/W/O’ dispersion were mainly changed stepwise. We were able to prepare microcapsules by the microencapsulation method adopted here. The content of core material was increased with the curdlan concentration and decreased with the impeller speed and the oil soluble surfactant concentration. With the curdlan concentration, the drying rate of microcapsules was decreased and the retention ability for water was increased due to the stable preservation of β-carotene.

Preparation of Microcapsules Containing β-Carotene with Thermo Sensitive Curdlan by Utilizing Reverse Dispersion

Science.gov (United States)

Taguchi, Yoshinari; Ono, Fumiyasu; Tanaka, Masato

2013-01-01

We have tried to microencapsulate β-carotene with curdlan of a thermogelation type polysaccharide. Microcapsules were prepared by utilizing reverse dispersion, in which salada oil was the continuous phase (O’) and the curdlan water slurry (W) was the dispersed phase. β-carotene (O) as a core material was broken into fine oil droplets in the dispersed phase to form the (O/W) dispersion. The (O/W) dispersion was poured in the continuous phase (O’) and stirred to form the (O/W)/O’ dispersion at room temperature and then, temperature of the dispersion was raised to 80 °C to prepare curdlan-microcapusles containing β-carotene. In this microencapsulation process, the concentrations of curdlan and oil soluble surfactant and the impeller speed to form the (O/W)/O’ dispersion were mainly changed stepwise. We were able to prepare microcapsules by the microencapsulation method adopted here. The content of core material was increased with the curdlan concentration and decreased with the impeller speed and the oil soluble surfactant concentration. With the curdlan concentration, the drying rate of microcapsules was decreased and the retention ability for water was increased due to the stable preservation of β-carotene. PMID:24300565

Dispersion stability of thermal nanofluids

Directory of Open Access Journals (Sweden)

Fan Yu

2017-10-01

Full Text Available Thermal nanofluids, the engineered fluids with dispersed functional nanoparticles, have exhibited extraordinary thermophysical properties and added functionalities, and thus have enabled a broad range of important applications. The poor dispersion stability of thermal nanofluids, however, has been considered as a long-existing issue that limits their further development and practical application. This review overviews the recent efforts and progresses in improving the dispersion stability of thermal nanofluids such as mechanistic understanding of dispersion behavior of nanofluids, examples of both water-based and oil-based nanofluids, strategies to stabilize nanofluids, and characterization techniques for dispersion behavior of nanofluids. Finally, on-going research needs, and possible solutions to research challenges and future research directions in exploring stably dispersed thermal nanofluids are discussed. Keywords: Thermal nanofluids, Dispersion, Aggregation, Electrostatic stabilization, Steric stabilization

Metal working oils. Cutting oils, rolling oils, quenching oils, rust preventive oils; Kinzoku kakoyu. Sessakuyu, atsuenyu, yakiireyu, boseiyu

Energy Technology Data Exchange (ETDEWEB)

Koyama, S. [Idemitsu Kosan Co. Ltd., Tokyo (Japan)

1996-04-01

With the demand against complicating working techniques for a background, foundations of the consideration for each of the lubricants in future are outlined. 1. Cutting oils: From the standpoint of speeding up and fireproofing, share of water-soluble type has come up to 30-40%. In this type, emulsifying dispersants and preservatives are combined. 2. Rolling oils: According to thinning of the standard thickness of steel plates, pressure of contacting surfaces has come up to 300 kg/mm{sup 2}(max.) and slip speed has increased too. In stainless steel plates, in order to get rid of the heat-streak (baking streak originated from wearing-out of oil film) shifting from neat oil to emulsion type is required. 3. Quenching oils: Following two systems are recent tendencies, the mineral oil system having excellent thermostability or the water system containing polyalkylneglycol etc., but the latter is expected from the viewpoint of fireproofing. 4. Rust preventive oils: As this oils do not aim at the rust prevention for long term, degreasing property is required. 20 refs., 5 figs., 1 tab.

Kaolinite and Silica Dispersions in Low-Salinity Environments: Impact on a Water-in-Crude Oil Emulsion Stability

Directory of Open Access Journals (Sweden)

Vladimir Alvarado

2011-10-01

Full Text Available This research aims at providing evidence of particle suspension contributions to emulsion stability, which has been cited as a contributing factor in crude oil recovery by low-salinity waterflooding. Kaolinite and silica particle dispersions were characterized as functions of brine salinity. A reference aqueous phase, representing reservoir brine, was used and then diluted with distilled water to obtain brines at 10 and 100 times lower Total Dissolved Solid (TDS. Scanning Electron Microscope (SEM and X-ray Diffraction (XRD were used to examine at the morphology and composition of clays. The zeta potential and particle size distribution were also measured. Emulsions were prepared by mixing a crude oil with brine, with and without dispersed particles to investigate emulsion stability. The clay zeta potential as a function of pH was used to investigate the effect of particle charge on emulsion stability. The stability was determined through bottle tests and optical microscopy. Results show that both kaolinite and silica promote emulsion stability. Also, kaolinite, roughly 1 mm in size, stabilizes emulsions better than larger clay particles. Silica particles of larger size (5 µm yielded more stable emulsions than smaller silica particles do. Test results show that clay particles with zero point of charge (ZPC at low pH become less effective at stabilizing emulsions, while silica stabilizes emulsions better at ZPC. These result shed light on emulsion stabilization in low-salinity waterflooding.

Synthesis and purification of oxide nanoparticle dispersions by modified emulsion precipitation.

Science.gov (United States)

Shi, Jingyu; Verweij, Henk

2005-06-07

ZrO2 and Fe2O3 precursor nanoparticles are synthesized, well-dispersed in decane, via a modified emulsion precipitation (MEP) method. This method starts with preparing two thermostable water-in-oil (w/o) emulsions with nonylphenol tetra(ethylene glycol) ether (Arkopal-40) as the main surfactant, didodecyldimethylammonium bromide (DiDAB) as the cosurfactant, decane as the continuous oil phase, and either a metal salt solution or a hexamethylenetetramine (HMTA) precipitation agent solution as the dispersed water phase. After mixing of the two emulsions, individual precursor particles are formed by precipitation in the confinement of the aqueous solution droplets. Excess water is removed by azeotropic distillation, and steric stabilization of the particles in the remaining oil medium is achieved with poly(octadecyl methacrylate) (PODMA), initially present dissolved in the oil phase. A purification process is conducted to remove the precipitation reaction byproduct and excess surfactants from the nanoparticle dispersions. Transmission electron microscopy (TEM) characterization shows that the ZrO2 and Fe2O3 precursor nanoparticles are both non-agglomerated, spherical, and have a narrow particle size distribution, centered at 4 nm in diameter. The precipitation from the dispersion of byproduct NH4Cl after water removal, and insoluble surfactant DiDAB after dilution with pure decane, is confirmed by X-ray diffraction (XRD). NMR results show that most of the oil-soluble surfactant Arkopal-40 can be removed from the dispersion by a 3x repeated dead-end pressure filtration process. It is shown that, after purification, the nanoparticle dispersions can be used for the preparation of homogeneous nanostructured coatings. The purification procedure as discussed provides guidelines for up-scaling the process and reuse of emulsifiers.

Modelling and assessment of accidental oil release from damaged subsea pipelines.

Science.gov (United States)

Li, Xinhong; Chen, Guoming; Zhu, Hongwei

2017-10-15

This paper develops a 3D, transient, mathematical model to estimate the oil release rate and simulate the oil dispersion behavior. The Euler-Euler method is used to estimate the subsea oil release rate, while the Eulerian-Lagrangian method is employed to track the migration trajectory of oil droplets. This model accounts for the quantitative effect of backpressure and hole size on oil release rate, and the influence of oil release rate, oil density, current speed, water depth and leakage position on oil migration is also investigated in this paper. Eventually, the results, e.g. transient release rate of oil, the rise time of oil and dispersion distance are determined by above-mentioned model, and the oil release and dispersion behavior under different scenarios is revealed. Essentially, the assessment results could provide a useful guidance for detection of leakage positon and placement of oil containment boom. Copyright © 2017 Elsevier Ltd. All rights reserved.

Experimental study on kinetics oil oil-suspended particulate matter aggregation

International Nuclear Information System (INIS)

Sun, J.; Environment Canada, Ottawa, ON; Khelifa, A.; Wang, Z.; Brown, C.; Fieldhouse, B.; Yang, C.; Zheng, X.; Wong, S.; So, L.C.

2009-01-01

Past studies of oil spills have shown that oil suspended particulate matter aggregates (OSAs) play a role in enhancing the natural cleansing of oiled shorelines. OSAs result from aggregation between suspended oil droplets and suspended particulate matter (SPM) in aquatic environments. During this process, oil dispersion into the water column is significantly increased since the surface of the oil droplet is surrounded by sediment particles. In addition, the accelerated biodegradation of the oil can be attributed to the greater oil-water contact area. This study focused on the kinetic aspects of OSA formation, with particular reference to the time scale of this process and its significance to oil dispersion following oil spills in water. A laboratory study was conducted to measure the time scale of OSA formation and its variations with mixing conditions. A reciprocating shaker and various oil/sediment mixtures were used to prepare the OSAs. Standard reference material 1941b was used as the natural sediment mixed with Arabian medium crude and artificial seawater under various mixing energies. The sediment-to-oil ratio remained constant for all experiments. Gas chromatography-flame ionization detection (GC-FID) analysis was used to measure the total petroleum hydrocarbons (TPH) trapped in negatively buoyant OSAs. Results showed that the TPH in OSAs increased exponentially with shaking time and reached an equilibrium value within 3 hours. The equilibrium decreased from 3 hours to 1.3 hours when the shaking rate increased from 2.0 to 2.3 Hz. It was concluded that high mixing energy enhances OSA formation and shortens the time for OSA formation. 42 refs., 6 tabs., 5 figs

Experimental study on kinetics oil oil-suspended particulate matter aggregation

Energy Technology Data Exchange (ETDEWEB)

Sun, J. [Ocean Univ. of China, Qingdoa (China). Environmental Science and Engineering Inst.; Environment Canada, Ottawa, ON (Canada). Emergencies Science and Technology Section, Emergencies, Operational Analytical Laboratories and Research Support Division; Khelifa, A.; Wang, Z.; Brown, C.; Fieldhouse, B.; Yang, C. [Environment Canada, Ottawa, ON (Canada). Emergencies Science and Technology Section, Emergencies, Operational Analytical Laboratories and Research Support Division; Zheng, X. [Ocean Univ. of China, Qingdoa (China). Environmental Science and Engineering Inst.; Wong, S. [Ottawa Univ., ON (Canada). Dept. of Chemistry; So, L.C. [Waterloo Univ., ON (Canada). Faculty of Engineering

2009-07-01

Past studies of oil spills have shown that oil suspended particulate matter aggregates (OSAs) play a role in enhancing the natural cleansing of oiled shorelines. OSAs result from aggregation between suspended oil droplets and suspended particulate matter (SPM) in aquatic environments. During this process, oil dispersion into the water column is significantly increased since the surface of the oil droplet is surrounded by sediment particles. In addition, the accelerated biodegradation of the oil can be attributed to the greater oil-water contact area. This study focused on the kinetic aspects of OSA formation, with particular reference to the time scale of this process and its significance to oil dispersion following oil spills in water. A laboratory study was conducted to measure the time scale of OSA formation and its variations with mixing conditions. A reciprocating shaker and various oil/sediment mixtures were used to prepare the OSAs. Standard reference material 1941b was used as the natural sediment mixed with Arabian medium crude and artificial seawater under various mixing energies. The sediment-to-oil ratio remained constant for all experiments. Gas chromatography-flame ionization detection (GC-FID) analysis was used to measure the total petroleum hydrocarbons (TPH) trapped in negatively buoyant OSAs. Results showed that the TPH in OSAs increased exponentially with shaking time and reached an equilibrium value within 3 hours. The equilibrium decreased from 3 hours to 1.3 hours when the shaking rate increased from 2.0 to 2.3 Hz. It was concluded that high mixing energy enhances OSA formation and shortens the time for OSA formation. 42 refs., 6 tabs., 5 figs.

Histopathologic and biochemical responses in Arctic marine bivalve molluscs exposed to experimentally spilled oil

Energy Technology Data Exchange (ETDEWEB)

Neff, J.M.; Hillman, R.E.; Carr, R.S.; Buhl, R.L.; Lahey, J.I.

1987-01-01

Following two experimental spills of chemically dispersed and undispersed crude oil in shallow bays on the northwest coast of Baffin Island bivalve molluscs accumulated significant amounts of petroleum hydrocarbons in bay receiving dispersed oil and in those receiving crude oil alone. Specimens of Mya truncata and Macoma calcarea for histopathologic examination were collected immediately before, immediately after and one year after the experimental oil spills. Immediately after there was increased gill and digestive tract necrosis in Mya from the chemically dispersed oil. After one year a few clams had granulocytomas throughout the tissues. Three clams receiving oil alone collected one year after the spill had invasive neoplasias. There were few lesions in Macoma immediatelly after or one year after the spill; animals had a high incidence of vacuolization of the digestive tubule epithelium. The incidence of parasitism and hemocytic infiltration also was higher in Maccoma. Clams Mya truncata were collected for biochemical analysis before, after and two weeks after the simulated oil spills. Concentations in the clam tissues of glucose, glycogen, trehalose, total lipid, and free amino acids were measured; free amino acids in adductor muscles were the most useful indices of pollutant stress. The results of the biochemical analyses indicate that Mya were not severely stressed by either dispersed oil or oil alone. After two weeks, clams from the dispersed oil bays were nearly normal, while those from the bay receiving oil alone appeared stressed. These results seem to corroborate results that the acute effects of dispersed oil are greater than those of undispersed oil, but effects of undispersed oil on infaunal molluscs develop more slowly and persist longer than those from dispersed oil. 43 refs., 2 figs., 6 tabs.

The effectiveness testing of oil spill-treating agents

International Nuclear Information System (INIS)

Fingas, M.F.; Kyle, D.A.; Laroche, N.; Fieldhouse, B.; Sergy, G.; Stoodley, G.

1995-01-01

Laboratory effectiveness tests have been developed for four classes of oil spill treating agents: solidifiers, demulsifying agents, surface-washing agents and dispersants. Several treating agent products in these four categories have been tested for effectiveness. The aquatic toxicity of these agents is an important factor and has been measured for many products. These results are presented. Solidifiers or gelling agents solidify oil. Test results show that solidifiers require between 16% and 200% of agent by weight compared to the oil. De-emulsifying agents or emulsion breakers prevent the formation of or break water-in-oil emulsions. Surfactant-containing materials are of two types, surface-washing agents and dispersants. Testing has shown that effectiveness is orthogonal for these two types of treating agents. Tests of surface washing agents show that only a few agents have effectiveness of 25 to 55%, where this is defined as the percentage of oil removed from a test surface. Dispersant effectiveness results using the swirling flask test are reported. Heavy oils show effectiveness values of about 1%, medium crudes of about 10%, light crude oils of about 30% and very light oils of about 90%

Liposomes incorporating essential oil of Brazilian cherry (Eugenia uniflora L.): characterization of aqueous dispersions and lyophilized formulations.

Science.gov (United States)

Yoshida, P A; Yokota, D; Foglio, M A; Rodrigues, R A F; Pinho, S C

2010-01-01

Multilamellar liposomes incorporating essential oil of Brazilian cherry (Eugenia uniflora L.) leaves were produced by dry film hydration. Gas chromatography demonstrated the compounds found in the essential oil were effectively incorporated in the aqueous dispersions of liposomes. Differential scanning calorimetry analyses revealed the incorporation of the essential oil did not cause phase separation in the membrane structure; the gel-liquid crystalline transition temperature (main transition) remained the same despite the higher heterogeneity indicated by the transition peak broadening. Different cryoprotectors (sucrose and trehalose) were added to the liposomal formulations to be tested in their ability to protect the liposomal structure during the lyophilization. The morphological aspect of the lyophilized powders analysed by scanning electron microscopy showed significant differences among the samples with and without cryoprotectors. Fourier-transform infrared spectroscopy indicated the cryoprotectors interacted effectively with the polar heads of phospholipids in the bilayer. In terms of water absorption, trehalose was identified as a much more effective protector agent against it than sucrose. The cryoprotectors showed different degrees of effectiveness of preservation of the liposomal structure when the rehydration assays of lyophilized liposomes were carried out, as particle size measurements indicated a moderate process of fusion when the formulations with sucrose were rehydrated.

Effects of shoreline treatment methods on intertidal biota in Prince William Sound

International Nuclear Information System (INIS)

Lees, D.C.; Houghton, J.P.; Driskell, W.B.

1993-01-01

Several studies conducted in Prince William Sound during 1989 were directed at assessing short term biological effects of treatment methods considered or employed for treating oil contaminated beaches. The four treatment alternatives evaluated in this paper are: low pressure warm water wash (LP-WW); high pressure hot water wash (HP-HW); the dispersant Corexit 7664; and the beach cleaner Corexit 9580 M2. Effects on the biota were assessed primarily on the basis of changes in the abundance of dominant taxa and the magnitude of selected community attributes (such as percent cover by algae or animals, and number of taxa). Significant reductions in one or more community or population attributes, and increases in the percent of dead mussels were observed in response to all types of treatment but the strongest and most consistent effects were observed following high pressure hot water treatment, which was also accompanied by heavy mortality in rockweed. Generally, the programs were not designed to discriminate among the potential causes of damage. However, available data suggest that neither chemical nor LP-WW treatments caused significant thermal impacts in the intertidal biota. In contrast, temperature appeared to cause significant mortality in the dominant plants and grazing and filter-feeding animals in HP-HW treatment sites. Observations of displacement and mortality for clams and mussels suggest that physical effects may be substantial in some cases. Of the types of treatment examined, dispersant and beach cleaner treatments appeared to be accompanied with the smallest number of significant changes in abundance; however, this conclusion is weak because the LP-WW wash accompanying chemical applications during the tests was sometimes less rigorous than when performed by itself. LP-WW treatment was accompanied by an intermediate level of changes whereas HP-HW treatment was accompanied with the highest percentage of changes, nearly all of which were decreases

Development of Permeable Reactive Barriers (PRB) Using Edible Oils

Science.gov (United States)

2008-06-01

naturally occurring processes of advection and dispersion to bring the contaminants to the treatment barrier. A large scale approach would be to form a...process has been developed for distributing soybean oil as an oil-in-water emulsion consisting of small oil droplets dispersed in a continuous...Thiele Kaolin Company, Sandersville, Georgia) was added to certain materials to evaluate the effect of increasing clay content. Grain size

Biodegradation of dispersants used in the treatment of oil spills

International Nuclear Information System (INIS)

Bergueiro Lopez, J.R.; Lalucat Jo, J.; Marti Moreno, A.; Morales Correas, N.

1993-01-01

The biodegradation of one of the most commonly used commercially available dispersants in the treatment of hydrocarbon out-flow was studied. The culture mediums employed were sea water, sterile sea water, and medium M19 (Merck). The latter two were inoculated with two kinds of microorganisms of the Pseudomona genus isolated from sludge from a waste treatment plant. The dispersants used is a commercial product made of anionic sulphated dispersants (1.710% by weight); anionic sulphonated dispersants (0.144%) and non-ionic dispersants (8.146%), both accompained by hidrocarbonated solvent (90%). The degradation processes occurred at differents temperatures (20, 30 and 37). The greatest degradation was obtained at 30 degree centigree. The degradation percentages obtained with the miscroorganisms were 40% of the anionic total and 70% of the non-ionic total after 56 hours for the 5:2 strain and 40% of the anionic total and 9.3% of the non-ionic total after 186 hours for the 1:3 strain. The sulphonated anionic dispersant fraction showed practically no degradation under these experimental conditions. The DBO, for a simple containing (Sterile) sea water and dispersant and inoculated with Pseudomonas was also determined. The value obtained was 595 mg. of O 2 /l. Sea water and medium M9 were used as a control. (Author)

Effects of COREXIT (registered trademark) EC9500A on Bacteria from a Beach Oiled by the Deepwater Horizon Spill

Science.gov (United States)

2011-01-01

reached the beach mid-day on the previous day. During sampling, small brown pea -sized floating drop - lets of oil were observed in the water within...economical method for measuring bacterial protein synthesis rates in seawater using 3H-leucine. Mar Microb Food Webs 6:107–114 US EPA (U.S

Ethoxyresorufin-O-deethylase activity and fixed wavelength fluorescence detection of PAHs metabolites in bile in turbot (Scophthalmus maximus L.) exposed to a dispersed topped crude oil in a continuous flow system

International Nuclear Information System (INIS)

Camus, L.; Aas, E.; Borseth, J.F.

1998-01-01

Long term effects of sublethal concentrations of oil on the marine environment have become of general concern. Cytochrome P4501A activity (EROD) in liver and fixed wavelength fluorescence detection of PAHs metabolites (FF) have in this study been used as biomarkers for dispersed oil exposure on a long term period of juvenile turbot (Scophthalmus maximus L.). A Continuous Flow System was used to carry out the study. The fish were continuously exposed to 0.125, 0.5 or 2.0 mg litre -1 dispersed topped crude oil for 6, 15, 24h 4 and 21 days followed by a 9 day recovery period in clean seawater. No induction of the cytochrome P4501A was measured. A maximum level in bile metabolites (4- to 5-fold) was recorded after 24h of exposure revealing thereby a detoxification process, but a decline occurred from day 4 to day 21. This study demonstrated that FF detection of PAHs metabolites in bile could be a more sensitive biomarker than EROD activity in a long term exposure to sublethal concentration of oil. (author)

Impact of salinity and dispersed oil on adsorption of dissolved aromatic hydrocarbons by activated carbon and organoclay

Energy Technology Data Exchange (ETDEWEB)

Younker, Jessica M.; Walsh, Margaret E., E-mail: mwalsh2@dal.ca

2015-12-15

Highlights: • Powdered activated carbon (PAC) outperformed organoclay for dissolved aromatics removal • Dispersed oil reduced the adsorption capacity of PAC but not organoclay • Salinity did not affect phenol or naphthalene removal by PAC or BTMA-organoclay • Commercial organoclay had reduced adsorption capacity in saline water due to aggregation • PAC performed better in single solute systems than multi-solute systems - Abstract: Adsorption capacity of phenol and naphthalene by powdered activated carbon (PAC), a commercial organoclay (OC) and a lab synthesized organoclay (BTMA) was studied using batch adsorption experiments under variable feed water quality conditions including single- and multi- solute conditions, fresh water, saline water and oily-and-saline water. Increasing salinity levels was found to reduce adsorption capacity of OC, likely due to destabilization, aggregation and subsequent removal of organoclay from the water column, but did not negatively impact adsorption capacity of PAC or BTMA. Increased dispersed oil concentrations were found to reduce the surface area of all adsorbents. This decreased the adsorption capacity of PAC for both phenol and naphthalene, and reduced BTMA adsorption of phenol, but did not negatively affect naphthalene removals by either organoclay. The presence of naphthalene as a co-solute significantly reduced phenol adsorption by PAC, but had no impact on organoclay adsorption. These results indicated that adsorption by PAC occurred via a surface adsorption mechanism, while organoclay adsorption occurred by hydrophobic or pi electron interactions. In general, PAC was more sensitive to changes in water quality than either of the organoclays evaluated in this study. However, PAC exhibited a higher adsorption capacity for phenol and naphthalene compared to both organoclays even in adverse water quality conditions.

Impact of salinity and dispersed oil on adsorption of dissolved aromatic hydrocarbons by activated carbon and organoclay

International Nuclear Information System (INIS)

Younker, Jessica M.; Walsh, Margaret E.

2015-01-01

Highlights: • Powdered activated carbon (PAC) outperformed organoclay for dissolved aromatics removal • Dispersed oil reduced the adsorption capacity of PAC but not organoclay • Salinity did not affect phenol or naphthalene removal by PAC or BTMA-organoclay • Commercial organoclay had reduced adsorption capacity in saline water due to aggregation • PAC performed better in single solute systems than multi-solute systems - Abstract: Adsorption capacity of phenol and naphthalene by powdered activated carbon (PAC), a commercial organoclay (OC) and a lab synthesized organoclay (BTMA) was studied using batch adsorption experiments under variable feed water quality conditions including single- and multi- solute conditions, fresh water, saline water and oily-and-saline water. Increasing salinity levels was found to reduce adsorption capacity of OC, likely due to destabilization, aggregation and subsequent removal of organoclay from the water column, but did not negatively impact adsorption capacity of PAC or BTMA. Increased dispersed oil concentrations were found to reduce the surface area of all adsorbents. This decreased the adsorption capacity of PAC for both phenol and naphthalene, and reduced BTMA adsorption of phenol, but did not negatively affect naphthalene removals by either organoclay. The presence of naphthalene as a co-solute significantly reduced phenol adsorption by PAC, but had no impact on organoclay adsorption. These results indicated that adsorption by PAC occurred via a surface adsorption mechanism, while organoclay adsorption occurred by hydrophobic or pi electron interactions. In general, PAC was more sensitive to changes in water quality than either of the organoclays evaluated in this study. However, PAC exhibited a higher adsorption capacity for phenol and naphthalene compared to both organoclays even in adverse water quality conditions.

The Norwegian Sea trial 1995 - offshore testing of two dispersant application systems and simulation of an underwater pipeline leakage - a summary paper

International Nuclear Information System (INIS)

Brandvik, P.J.; Strom-Kristiansen, T.; Lewis, A.; Daling, P.S.; Reed, M.; Rye, H.; Jensen, H.

1996-01-01

A summary of the major findings from several reports regarding oil spills at sea, was presented. Topics included oil weathering, remote sensing, underwater plume behaviour, oil spill drifters and underwater oil concentrations. To study plume behaviour, oil was released from 100 metres depth. The objective of the underwater release was to simulate a pipeline leakage without gas and high pressure and to study the behaviour of the rising plume. The different methods of applying dispersants were evaluated to determine their effectiveness. It was concluded that, if correctly applied, a dispersant is capable of dispersing the thick oil totally into the seawater within 10 to 30 minutes after treatment. A slick treated with dispersant applied from a helicopter bucket was most effective. 19 refs., 6 figs

Distribution of dispersed oil phase in hydrocarbon fermentations

Energy Technology Data Exchange (ETDEWEB)

Ho, C S; Erickson, L E

1978-04-01

Recent experimental results show that the spreading coefficient frequently becomes positive when Candida lipolytica is cultivated on n-hexadecane. The effects of oil spreading at the surface of air bubbles in an airlift fermentor are examined using a mathematical model. The distribution of the oil phase with position and among the phases is determined using computer simulation. The simulation results qualitatively explain some of the experimental observations which have been previously reported.

Laboratory tests, experimental oil spills, models, and reality: The Braer oil spill

International Nuclear Information System (INIS)

Reed, M.; Daling, P.S.; Brandvik, P.J.; Singsaas, I.

1993-01-01

The IKU Petroleum Research organization in Norway has accumulated data on the weathering behavior of spilled oils and petroleum products, mainly pertaining to North Sea crudes. Recent weathering research at IKU has been carried out in an elliptical mesoscale flume and in field tests consisting of experimental releases of crude oil. Results of these tests provided information on oil spill dispersion, evaporation, and emulsification. When the tanker Braer grounded in the Shetland Islands in January 1993 in extreme environmental conditions, the imminent release of a load of 84,000 tonnes of North Sea oil confronted response personnel with a variety of issues including the use of dispersants as a response action. Relevant information on the expected behavior of the crude was obtained within a day of the grounding as a result of close relations between IKU and Warren Spring Laboratory. The question is raised whether such information, which could have been spread between several organizations around the world, will be rapidly accessible in the event of another major spill. It is proposed to establish an electronically accessible database on the behavior and fate of specific oils and petroleum products to address this problem. 9 refs., 4 figs

Prediction of oil droplet size distribution in agitated aquatic environments

International Nuclear Information System (INIS)

Khelifa, A.; Lee, K.; Hill, P.S.

2004-01-01

Oil spilled at sea undergoes many transformations based on physical, biological and chemical processes. Vertical dispersion is the hydrodynamic mechanism controlled by turbulent mixing due to breaking waves, vertical velocity, density gradients and other environmental factors. Spilled oil is dispersed in the water column as small oil droplets. In order to estimate the mass of an oil slick in the water column, it is necessary to know how the droplets formed. Also, the vertical dispersion and fate of oil spilled in aquatic environments can be modelled if the droplet-size distribution of the oil droplets is known. An oil spill remediation strategy can then be implemented. This paper presented a newly developed Monte Carlo model to predict droplet-size distribution due to Brownian motion, turbulence and a differential settling at equilibrium. A kinematic model was integrated into the proposed model to simulate droplet breakage. The key physical input of the model is the maximum droplet size permissible in the simulation. Laboratory studies were found to be in good agreement with field studies. 26 refs., 1 tab., 5 figs

Liquid agents for dispersion of hard alloys

International Nuclear Information System (INIS)

Putintseva, M.N.

2006-01-01

Effects of dispersant properties on granulometric, chemical, and phase composition of the products of WC hard alloy electroerosion are considered. It is established that an increase of liquid dispersant permittivity results in enhanced powder dispersity, and an increase of boiling temperature and kinematic viscosity of a hydrocarbon liquid promotes a carbon loss from WC and intensifies pyrolysis of the liquid.On electroerosion of WC base hard alloy in oil a powder particle consists of b-WC+W 2 C phases, in kerosine - of a-WC+b-WC, in distilled water - of W+W 2 C. The viscosity of liquid dispersants practically has no effect on powder particle size [ru

Use of passive samplers for improving oil toxicity and spill effects assessment

International Nuclear Information System (INIS)

Letinski, Daniel; Parkerton, Thomas; Redman, Aaron; Manning, Ryan; Bragin, Gail; Febbo, Eric; Palandro, David; Nedwed, Tim

2014-01-01

Highlights: • Methods to quantify dissolved hydrocarbons needed to link oil exposures to toxicity. • Solid phase microextraction (SPME) fibers used to measure dissolved hydrocarbons. • SPME results reliably predicted acute toxicity for range of dispersed oils. • Oil droplets and chemical dispersant did not significantly contribute to toxicity. • SPME analysis improves oil exposure assessment in lab and field studies. - Abstract: Methods that quantify dissolved hydrocarbons are needed to link oil exposures to toxicity. Solid phase microextraction (SPME) fibers can serve this purpose. If fibers are equilibrated with oiled water, dissolved hydrocarbons partition to and are concentrated on the fiber. The absorbed concentration (C polymer ) can be quantified by thermal desorption using GC/FID. Further, given that the site of toxic action is hypothesized as biota lipid and partitioning of hydrocarbons to lipid and fibers is well correlated, C polymer is hypothesized to be a surrogate for toxicity prediction. To test this method, toxicity data for physically and chemically dispersed oils were generated for shrimp, Americamysis bahia, and compared to test exposures characterized by C polymer . Results indicated that C polymer reliably predicted toxicity across oils and dispersions. To illustrate field application, SPME results are reported for oil spills at the Ohmsett facility. SPME fibers provide a practical tool to improve characterization of oil exposures and predict effects in future lab and field studies

Solubilization of tea seed oil in a food-grade water-dilutable microemulsion.

Directory of Open Access Journals (Sweden)

Lingli Deng

Full Text Available Food-grade microemulsions containing oleic acid, ethanol, Tween 20, and water were formulated as a carrier system for tea seed oil (Camellia oleifera Abel.. The effect of ethanol on the phase behavior of the microemulsion system was clearly reflected in pseudo-ternary diagrams. The solubilization capacity and solubilization efficiency of tea seed oil dispersions were measured along the dilution line at a 70/30 surfactant/oil mass ratio with Tween 20 as the surfactant and oleic acid and ethanol (1:3, w/w as the oil phase. The dispersed phase of the microemulsion (1.5% weight ratio of tea seed oil to the total amount of oil, surfactant, and tea seed oil could be fully diluted with water without phase separation. Differential scanning calorimetry and viscosity measurements indicated that both the carrier and solubilized systems underwent a similar microstructure transition upon dilution. The dispersion phases gradually inverted from the water-in-oil phase ( 45% water along the dilution line.

PETROLEUM-COLLECTING AND DISPERSING CHEMICALS FOR ...

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Films of petroleum origin reflecting sunlight rays hinder absorption of energy by water necessary for life ... Dispersing chemicals like mechanical clean-up methods have their own place in fighting oil spills. They are ... yellow color, and filtered.

Quantification of the effect of oil layer thickness on entrainment of surface oil

NARCIS (Netherlands)

Klaas Dijkstra; Albertinka J. Murk; Marieke Zeinstra-Helfrich; Wierd Koops

2015-01-01

This study quantifies the effect of oil layer thickness on entrainment and dispersion of oil into seawater, using a plunging jet with a camera system. In contrast to what is generally assumed, we revealed that for the low viscosity “surrogate MC252 oil” we used, entrainment rate is directly

Mitigating oil spills in the water column

International Nuclear Information System (INIS)

Barry, Edward; Libera, Joseph A.; Mane, Anil University; Avila, Jason R.; DeVitis, David

2017-01-01

The scale and scope of uncontrolled oil spills can be devastating. Diverse marine environments and fragile ecologies are some of the most susceptible to the many ill effects, while the economic costs can be crippling. A notoriously difficult challenge with no known technological solution is the successful removal of oil dispersed in the water column. Here, we address this problem through cheap and reusable oil sorbents based on the chemical modification of polymer foams. Interfacial chemistry was optimized and subsequently tested in a simulated marine environment at the National Oil Spill Response Research & Renewable Energy Test Facility, Ohmsett. We find favorable performance for surface oil mitigation and, for the first time, demonstrate the advanced sorbent's efficiency and efficacy at pilot scale in extraction of crude oil and refined petroleum products dispersed in the water column. As a result, this is a potentially disruptive technology, opening a new field of environmental science focused on sub-surface pollutant sequestration.

Oil mixing behavior after an oil spill: identification conflicts of different fingerprints.

Science.gov (United States)

He, Shijie; Yu, Hongjun; Luo, Yongming; Wang, Chuanyuan; Li, Xueshuang; Li, Zhongping

2018-04-01

Clearing up whether spilled oil is mixed or not can strengthen the accuracy of oil spill identification. In the present study, the biomarkers in spilled oil samples were detected. The weathering modes of different types of diagnostic ratio and carbon isotope values of individual n-alkanes were also analyzed. The results showed that the diagnostic ratios of steroids, terpenes and aromatics, and weathering characteristics of carbon isotope composition (δ 13 C) of individual n-alkanes supported the idea that Dalian oil spill emerged from a single oil source. Furthermore, commonly used diagnostic ratios of n-alkanes indicated that the Dalian oil spill had undergone the oil mixing process. The different identifying outcomes indicate that some kinds of n-alkane-rich substance (such as oil dispersants) were mixed in the Dalian spilled oil and interfered with the routine diagnosis ratios of n-alkanes.

Rapid determination of hydrophilic phenols in olive oil by vortex-assisted reversed-phase dispersive liquid-liquid microextraction and screen-printed carbon electrodes.

Science.gov (United States)

Fernández, Elena; Vidal, Lorena; Canals, Antonio

2018-05-01

A novel approach is presented to determine hydrophilic phenols in olive oil samples, employing vortex-assisted reversed-phase dispersive liquid-liquid microextraction (RP-DLLME) for sample preparation and screen-printed carbon electrodes for voltammetric analysis. The oxidation of oleuropein, hydroxytyrosol, caffeic acid, ferulic acid and tyrosol was investigated, being caffeic acid and tyrosol selected for quantification. A matrix-matching calibration using sunflower oil as analyte-free sample diluted with hexane was employed to compensate matrix effects. Samples were analyzed under optimized RP-DLLME conditions, i.e., extractant phase, 1M HCl; extractant volume, 100µL; extraction time, 2min; centrifugation time, 10min; centrifugation speed, 4000rpm. The working range showed a good linearity between 0.075 and 2.5mgL -1 (r = 0.998, N = 7) for caffeic acid, and between 0.075 and 3mgL -1 (r = 0.999, N = 8) for tyrosol. The methodological limit of detection was empirically established at 0.022mgL -1 for both analytes, which is significantly lower than average contents found in olive oil samples. The repeatability was evaluated at two different spiking levels (i.e., 0.5mgL -1 and 2mgL -1 ) and coefficients of variation ranged from 8% to 11% (n = 5). The applicability of the proposed method was tested in olive oil samples of different quality (i.e., refined olive oil, virgin olive oil and extra virgin olive oil). Relative recoveries varied between 83% and 108% showing negligible matrix effects. Finally, fifteen samples were analyzed by the proposed method and a high correlation with the traditional Folin-Ciocalteu spectrophotometric method was obtained. Thereafter, the concentrations of the fifteen oil samples were employed as input variables in linear discriminant analysis in order to distinguish between olive oils of different quality. Copyright © 2017 Elsevier B.V. All rights reserved.

A new concept for improved oil spill containment in open waters

International Nuclear Information System (INIS)

Sethness, E.D. Jr.

1990-01-01

In this paper a new concept for improved oil spill containment in open waters is presented. The proposed system is a combination oil boom and wave barrier. Waveguard International has taken its extensive experience as a designer of floating breakwaters and applied this knowledge into the design of a readily transportable, readily deployable floating oil boom with integrated wave attenuation capabilities as well. The new concept is based on the attenuation of the two major natural causes of oil spill dispersion; first, horizontal dispersion caused by wind shear effects; and second, vertical entrainment into the water column caused by the mixing action of wave motion. The physical encirclement of an oil spill with a floating boom to contain horizontal dispersion is not a new concept. Existing systems, however, work best in calm water and rapidly loose efficiency as waves increase. The proposed system can not only physically surround the spill area, but is as much as 90% effective in stopping the transmission of wave energy. The oil boom thus minimizes vertical mixing of the contained oil slick

Spreading, retention and clean-up of oil spills. Final report

Energy Technology Data Exchange (ETDEWEB)

Wilson, Jr, M P

1976-05-01

This study reviews and assesses the technology of oil spill spreading, retention and cleanup and proposes research needs in these areas. Sources of oil spills are analyzed and the difficulty of gathering meaningful statistics is discussed. Barrier technology is reviewed and problem areas analyzed. Natural and forced biodegradation and natural and chemical dispersion of oil spills are considered. Research recommendations are categorized under the following two headings (1) Preventive techniques and (2) Containment, Cleanup and Dispersion.

Effect of asphaltenes on crude oil wax crystallization

DEFF Research Database (Denmark)

Kriz, Pavel; Andersen, Simon Ivar

2005-01-01

The paper summarizes the experimental work done on asphaltene influenced wax crystallization. Three different asphaltenes (from stable oil, instable oil, and deposit) were mixed at several concentrations or dispersions into the waxy crude oil. These blends were evaluated by viscometry and yield s...

Solid lipid dispersions: potential delivery system for functional ingredients in foods.

Science.gov (United States)

Asumadu-Mensah, Aboagyewa; Smith, Kevin W; Ribeiro, Henelyta S

2013-07-01

Structured solid lipid (SL) systems have the advantages of long-term physical stability, low surfactant concentrations, and may exhibit controlled release of active ingredients. In this research work, the potential use of high-melting SLs for the production of the above structured SL carrier systems was investigated. Dispersions containing either SL or blend of solid lipid and oil (SL+O) were produced by a hot melt high-pressure homogenization method. Experiments involved the use of 3 different SLs for the disperse phase: stearic acid, candelilla wax and carnauba wax. Sunflower oil was incorporated in the disperse phase for the production of the dispersions containing lipid and oil. In order to evaluate the practical aspects of structured particles, analytical techniques were used including: static light scattering to measure particle sizes, transmission electron microscopy (TEM) for investigating particle morphology and differential scanning calorimetry (DSC) to investigate the crystallization behavior of lipids in bulk and in dispersions. Results showed different mean particle sizes depending on the type of lipid used in the disperse phase. Particle sizes for the 3 lipids were: stearic acid (SL: 195 ± 2.5 nm; SL+O: 138 ± 6.0 nm); candelilla wax (SL: 178 ± 1.7 nm; SL+O: 144 ± 0.6 nm); carnauba wax (SL: 303 ± 1.5 nm; SL+O: 295 ± 5.0 nm). TEM results gave an insight into the practical morphology, showing plate-like and needle-like structures. DSC investigations also revealed that SL dispersions melted and crystallized at lower temperatures than the bulk. This decrease can be explained by the small particle sizes of the dispersion, the high-specific surface area, and the presence of a surfactant. © 2013 Institute of Food Technologists®

Partitioning of semi-soluble organic compounds between the water phase and oil droplets in produced water

Energy Technology Data Exchange (ETDEWEB)

Faksness, Liv-Guri; Grini, Per Gerhard; Daling, Per S

2004-04-01

When selecting produced water treatment technologies, one should focus on reducing the major contributors to the total environmental impact. These are dispersed oil and semi-soluble hydrocarbons, alkylated phenols, and added chemicals. Experiments with produced water have been performed offshore on the Statoil operated platforms Gullfaks C and Statfjord B. These experiments were designed to find how much of the environmentally relevant compounds were dissolved in the water phase and not associated to the dispersed oil in the produced water. Results show that the distribution between the dispersed oil and the water phase varies highly for the different components groups. For example the concentration of PAHs and the C6-C9 alkylated phenols is strongly correlated to the content of dispersed oil. Therefore, the technologies enhancing the removal of dispersed oil have a higher potential for reducing the environmental impact of the produced water than previously considered.

Partitioning of semi-soluble organic compounds between the water phase and oil droplets in produced water

International Nuclear Information System (INIS)

Faksness, Liv-Guri; Grini, Per Gerhard; Daling, Per S.

2004-01-01

When selecting produced water treatment technologies, one should focus on reducing the major contributors to the total environmental impact. These are dispersed oil and semi-soluble hydrocarbons, alkylated phenols, and added chemicals. Experiments with produced water have been performed offshore on the Statoil operated platforms Gullfaks C and Statfjord B. These experiments were designed to find how much of the environmentally relevant compounds were dissolved in the water phase and not associated to the dispersed oil in the produced water. Results show that the distribution between the dispersed oil and the water phase varies highly for the different components groups. For example the concentration of PAHs and the C6-C9 alkylated phenols is strongly correlated to the content of dispersed oil. Therefore, the technologies enhancing the removal of dispersed oil have a higher potential for reducing the environmental impact of the produced water than previously considered

The Physical State of Emulsified Edible Oil Modulates Its in Vitro Digestion.

Science.gov (United States)

Guo, Qing; Bellissimo, Nick; Rousseau, Dérick

2017-10-18

Emulsified lipid digestion was tailored by manipulating the physical state of dispersed oil droplets in whey protein stabilized oil-in-water (O/W) emulsions, where the oil phase consisted of one of five ratios of soybean oil (SO) and fully hydrogenated soybean oil (FHSO). The evolution in particle size distribution, structural changes during oral, gastric, and intestinal digestion, and free fatty acid release during intestinal digestion were all investigated. Irrespective of the physical state and structure of the dispersed oil/fat, all emulsions were stable against droplet size increases during oral digestion. During gastric digestion, the 50:50 SO:FHSO emulsion was more stable against physical breakdown than any other emulsion. All emulsions underwent flocculation and coalescence or partial coalescence upon intestinal digestion, with the SO emulsion being hydrolyzed the most rapidly. The melting point of all emulsions containing FHSO was above 37 °C, with the presence of solid fat within the dispersed oil droplets greatly limiting lipolysis. Fat crystal polymorph and nanoplatelet size did not play an important role in the rate and extent of lipid digestion. Free fatty acid release modeled by the Weibull distribution function showed that the rate of lipid digestion (κ) decreased with increasing solid fat content, and followed an exponential relationship (R 2 = 0.95). Overall, lipid digestion was heavily altered by the physical state of the dispersed oil phase within O/W emulsions.

Numerical 3D modelling of oil dispersion in the sea due to different accident scenarios

Science.gov (United States)

Guandalini, Roberto; Agate, Giordano; Moia, Fabio

2017-04-01

The purpose of the study has been the development of a methodology, based on a numerical 3D approach, for the analysis of oil dispersion in the sea, in order to simulate with a high level of accuracy the dynamic behavior of the oil plume and its displacement in the environment. As a matter of fact, the numerical simulation is the only approach currently able to analyse in detail possible accident scenarios, even with an high degree of complexity, of different type and intensity, allowing to follow their evolution both in time and space, and to evaluate the effectiveness of suggested prevention or recovery actions. The software for these calculations is therefore an essential tool in order to simulate the impact effects in the short, medium and long period, able to account for the complexity of the sea system involved in the dispersion process and its dependency on the meteorological, marine and morphological local conditions. This software, generally based on fluid dynamic 3D simulators and modellers, is therefore extremely specialized and requires expertise for an appropriate usage, but at the same time it allows detailed scenario analyses and design verifications. It takes into account different parameters as the sea current field and its turbulence, the wind acting on the sea surface, the salinity and temperature gradients, the local coastal morphology, the seabed bathymetry and the tide. The applied methodology is based on the Integrated Fluid Dynamic Simulation System HyperSuite developed by RSE. This simulation system includes the consideration of all the parameters previously listed, in the frame of a 3D Eulerian finite element fluid dynamic model, which accuracy is guaranteed by a very detailed spatial mesh and by an automatically optimized time step management. In order to assess the methodology features, an area of more than 2500 km2 and depth of 200 m located in the middle Adriatic Sea has been modelled. The information required for the simulation in

New test for oil soluble/water dispersible gas pipeline inhibitors

Energy Technology Data Exchange (ETDEWEB)

Stegmann, D.W.; Asperger, R.G.

1987-01-01

The wheel test provides good mixing of the condensate and water phases, the coupons are exposed to both phases. Therefore, the wheel test cannot distinguish between inhibitors that need continuous mixing of the these phases to maintain a water dispersion of the inhibitor and inhibitors that will self disperse into the water. This concept becomes important for pipelines in stratified flow where the water can settle out. In these cases with low turbulence, the inhibitor must self disperse into the water to be effective. The paper describes a test method to measure the effectiveness of an inhibitor and its ability to self disperse. The effectiveness of several inhibitors as predicted by the new test method is discussed relative to data from the wheel test and breaker tests. Field performance of these inhibitors in a gas gathering line, with liquids in stratified flow, are cities and compared with the results of the various laboratory tests.

Wave tank to simulate the movement of oil under breaking waves

International Nuclear Information System (INIS)

Botrus, D.; Wickley-Olsen, E.; Boufadel, M.C.; Weaver, J.W.; Weggle, R.; Lee, K.; Venosa, A.D.

2008-01-01

Methods to mitigate offshore oil spills before they reach the shoreline have been investigated in order to reduce environmental impacts. Artificial dispersants are commonly used on offshore oil spills to decrease the interfacial tension between the oil and water. The wave action helps break the slick into droplets that penetrate into the sea. This paper presented the results of wave tank tests in which the effectiveness of dispersants was evaluated. The focus was on the transport of oil during the breakup of a wave. In this study, the energy dissipation rate per unit mass was evaluated at various depths in the tank for regular and breaking waves. It was shown that breaking waves play an important role in the dispersion of oil at sea. Contrary to previous studies which suggested that the plume moves forward following the breaker, the results of this study showed that the plume splits into two parts, with one part going upstream. Understanding how the plume travels will provide insight as to where to add the dispersant with respect to the location of the breaker. The addition of the dispersant should take place before the location of the breaker. It was concluded that future work should include computational fluid dynamics simulation, as well as the use of a higher resolution camera. 9 refs., 17 figs

SOVENT BASED ENHANCED OIL RECOVERY FOR IN-SITU UPGRADING OF HEAVY OIL SANDS

Energy Technology Data Exchange (ETDEWEB)

Munroe, Norman

2009-01-30

With the depletion of conventional crude oil reserves in the world, heavy oil and bitumen resources have great potential to meet the future demand for petroleum products. However, oil recovery from heavy oil and bitumen reservoirs is much more difficult than that from conventional oil reservoirs. This is mainly because heavy oil or bitumen is partially or completely immobile under reservoir conditions due to its extremely high viscosity, which creates special production challenges. In order to overcome these challenges significant efforts were devoted by Applied Research Center (ARC) at Florida International University and The Center for Energy Economics (CEE) at the University of Texas. A simplified model was developed to assess the density of the upgraded crude depending on the ratio of solvent mass to crude oil mass, temperature, pressure and the properties of the crude oil. The simplified model incorporated the interaction dynamics into a homogeneous, porous heavy oil reservoir to simulate the dispersion and concentration of injected CO2. The model also incorporated the characteristic of a highly varying CO2 density near the critical point. Since the major challenge in heavy oil recovery is its high viscosity, most researchers have focused their investigations on this parameter in the laboratory as well as in the field resulting in disparaging results. This was attributed to oil being a complex poly-disperse blend of light and heavy paraffins, aromatics, resins and asphaltenes, which have diverse behaviors at reservoir temperature and pressures. The situation is exacerbated by a dearth of experimental data on gas diffusion coefficients in heavy oils due to the tedious nature of diffusivity measurements. Ultimately, the viscosity and thus oil recovery is regulated by pressure and its effect on the diffusion coefficient and oil swelling factors. The generation of a new phase within the crude and the differences in mobility between the new crude matrix and the

Aqueous solubility, dispersibility and toxicity of biodiesels

International Nuclear Information System (INIS)

Hollebone, B.P.; Fieldhouse, B.; Lumley, T.C.; Landriault, M.; Doe, K.; Jackman, P.

2007-01-01

The renewed interest in the use of biological fuels can be attributed to that fact that feedstocks for fatty-acid ester biodiesels are renewable and can be reclaimed from waste. Although there are significant benefits to using biodiesels, their increased use leaves potential for accidental release to the environment. Therefore, their environmental behaviours and impacts must be evaluated along with the risk associated with their use. Biodiesel fuels may be made from soy oil, canola oil, reclaimed restaurant grease, fish oil and animal fat. The toxicological fate of biofuel depends on the variability of its chemical composition. This study provided an initial assessment of the aqueous fate and effects of biodiesel from a broad range of commonly available feedstocks and their blends with petroleum diesels. The study focused primarily on the fate and impact of these fuels in fresh-water. The use of chemical dispersion as a countermeasure for saltwater was also investigated. The exposure of aquatic ecosystems to biodiesels and petroleum diesel occurs via the transfer of material from the non-aqueous phase liquid (NAPL) into the aqueous phase, as both soluble and dispersed components. The aqueous solubilities of the fuels were determined from the equilibrium water-accommodated fraction concentrations. The acute toxicities of many biodiesels were reported for 3 test species used by Environment Canada for toxicological evaluation, namely rainbow trout, the water flea and a luminescent bacterium. This study also evaluated the natural potential for dispersion of the fuels in the water column in both low and high-energy wave conditions. Chemical dispersion as a potential countermeasure for biodiesel spills was also evaluated using solubility testing, acute toxicity testing, and dispersibility testing. It was shown that biodiesels have much different fates and impacts from petroleum diesels. The compounds partitioning into the water column are also very different for each

Dispersion of Waxy Gas Oil by Some Nonionic Surfactants

International Nuclear Information System (INIS)

Khidr, T.T.; Mahmoud, S.A.

2004-01-01

Straight chain fatty alcohols having the following number of carbon atoms C 12 , C 14 , C 18 and C 21 each alcohol was ethoxylated to the same of ethylene oxide content, characterized through average molecular weight and elemental analysis. The surface properties of these compounds were studied through surface tension measurements. The synthesized additives were tested as flow improvers for improving the cold flow properties of two waxy gas oils through pour point test. The results show the right efficiency of these compounds in improving the flow ability. Comparative evaluation of the synthesized products with available commercial additive (com) showed their efficiency and suitability to use in gas oils. Wax modification was assisted through photo analysis. Correlation between wax modification and flow improvement in term of pour point depression appeared to be merely qualitative in such heterogeneous gas oil systems

Dispersed-phase catalysis in coal liquefaction

International Nuclear Information System (INIS)

Utz, B.R.; Cugini, A.V.; Frommell, E.A.

1990-01-01

This paper reports that the specific reaction (activation) conditions for the conversion of catalyst precursors to unsupported catalyst have a direct effect on the catalytic activity and dispersion. The importance of reaction intermediates in decomposition of ammonium heptamolybdate and ammonium tetrathiomolybdate, and the sensitivity of these intermediates to reaction conditions, were studied in coal liquefaction systems. Recent results indicate that optimization of activation conditions facilitates the formation of a highly dispersed and active form of molybdenum disulfide for coal liquefaction. The use of the catalyst precursors ammonium heptamolybdate, ammonium tetrathiomolybdate, and molybdenum trisulfide for the conversion of coal to soluble products will be discussed. The use of an unsupported dispersed-phase catalyst for direct coal liquefaction is not a novel concept and has been employed in may studies with varying success. Dispersed-phase catalysts soluble and oil-soluble salts, and as finely divided powders. While some methods of catalyst introduction give higher dispersion of the catalyst and greater activity for the liquefaction of coal, all of the techniques allow the formation of a finely dispersed inorganic phase

Polymer Inclusion Membranes with Strip Dispersion

Directory of Open Access Journals (Sweden)

Yueh-Hsien Li

2017-06-01

Full Text Available The present work investigated the permeation of indium ions through a polymer inclusion membrane (PIM, prepared with cellulose triacetate (CTA as the base polymer, tris(2-butoxyethyl phosphate (TBEP as the plasticizer and di-(2-ethylhexylphosphoric acid (D2EHPA as the extractant. With 5 M HCl aqueous solution as the strip solution, we observed an initial indium permeability of 2.4 × 10−4 m/min. However, the permeability decreases with time, dropping to about 3.4 × 10−5 m/min after 200 min of operation. Evidence was obtained showing that hydrolysis of CTA occurred, causing a dramatic decrease in the feed pH (protons transported from strip to feed solutions and a loss of extractant and plasticizer from the membrane, and then leading to the loss of indium permeability. To alleviate the problem of hydrolysis, we proposed an operation scheme called polymer inclusion membranes with strip dispersion: dispersing the strip solution in extractant-containing oil and then bringing the dispersion to contact with the polymer membrane. Since the strong acid was dispersed in oil, the membrane did not directly contact the strong acid at all times, and membrane hydrolysis was thus alleviated and the loss of indium permeability was effectively prevented. With the proposed scheme, a stable indium permeability of 2.5 × 10−4 m/min was obtained during the whole time period of the permeation experiment.

Potentially beneficial spill-related effects of chemicals routinely added to crude oils

International Nuclear Information System (INIS)

Ross, S.; Maharaj, S.

1993-01-01

Amoco Trinidad Oil Company produces 60,000 bbl/d of oil from the Trinidadian offshore. The oil is pipelined ashore where it is processed and returned offshore to a buoy mooring for transport up Trinidad's east coast. Amoco Trinidad has developed comprehensive oil spill contingency plans, starting from computer models of spill scenarios. The models used initially assumed that the oils would emulsify quickly and the spills would become highly viscous and persistent, reaching the shoreline in 15-24 h. Such behavior would render ineffective the use of dispersants as a spill countermeasure. Studies showed a poor potential capability of physical recovery systems for spills off the Trinidad east coast due to high sea states, strong winds, and other factors. These results led to questioning of the spill model's assumptions, and laboratory tests were conducted to study the actual behavior of the crude oils. It was found that the oil was difficult to emulsify and highly prone to breakup and dispersion. These surprising results were explained by the presence of surfactants added during processing. A revised modelling exercise showed that if the surfactants stay with the oil, spills up to 100,000 bbl will dissipate in 15 h or less at average wind conditions. To guard against the possibility that the surfactants may not stay with the spilled oil, and to help accelerate dispersion of oil spills, Amoco Trinidad has developed a dispersant-use capacity for its spill contingency plan. It is suggested that additives normally added to crude oils during production and processing in other areas may also be providing spill cleanup benefits similar to those found in the Trinidad case. 9 refs., 1 fig., 4 tabs

Ecological impacts of the Deepwater Horizon oil spill: implications for immunotoxicity

Science.gov (United States)

Summary of major Federal and multi-stake holder research efforts in response to the DWH spill, including laboratory oil dispersant testing, estimation of oil release rates and oil fate calculations, subsea monitoring, and post-spill assessments. Impacts from shoreline oiling, wil...

Radiation response of vitamin A in aqueous dispersions

International Nuclear Information System (INIS)

Bhushan, B.; Kumta, U.S.

1977-01-01

The radiation destruction of vitamin A acetate was monitored in isooctane, coconut oil, and aqueous dispersions. The G(-vit. A), i.e., the number of vitamin A molecules destroyed per 100 eV of energy absorbed in lipid solvents and aqueous preparations, increased with the concentrations of vitamin A used. In the freely dissolved state, as in isooctane or coconut oil, the extent of destruction of vitamin A was more or less identical. However, a marked reduction in the radiation destruction of vitamin A was observed in aqueous dispersions at all concentrations except at 1 x 10 -4 M. Incorporation of sugars, starch, and egg albumin in aqueous preparations offered considerable protection to vitamin A from radiation damage which could be discerned even at the lowest concentration (1 x 10 -4 M). The protective influence of aqueous dispersion as noted for vitamin A was also observed for β-carotene, vitamin A alcohol, and ubiquinone-30. The significance of the above findings in radiation processing of foods has been discussed

A catalogue of crude oil and oil product properties, 1990

International Nuclear Information System (INIS)

Bobra, M.A.; Callaghan, S.

1990-09-01

This catalogue is a compilation of available data on crude oils and petroleum products. The emphasis of the catalogue is upon oils which could potentially impact Canada's environment. Other oils which are unlikely to be of direct Canadian concern are also included because they have been well characterized and used in relevant studies. The properties listed for each oil are those which will provide an indication of a spilled oil's environmental behaviour and effects. The properties on which data is provided include API gravity, density, viscosity, interfacial tension, pour point, flash point, vapor pressure, volatility and component distribution, emulsion formation tendency and stability, weathering, dispersability, major hydrocarbon groups, aqueous solubility, toxicity, sulfur content, fire point, and wax content. Most of the chemical-physical properties listed in this catalogue were measured using standard tests. For certain properties, data are given at different temperatures and for different degrees of oil weathering. An oil's degree of weathering is expresed as the volume or weight percent evaporated from the fresh oil. Weathered oils used for testing were artificially weathered by gas stripping following the method of Mackay and Stiver. 109 refs

A catalogue of crude oil and oil product properties, 1992

International Nuclear Information System (INIS)

Whiticar, S.; Bobra, M.; Liuzzo, P.; Callaghan, S.; Fingas, M.; Jokuty, P.; Ackerman, F.; Cao, J.

1993-02-01

This catalogue is a compilation of available data on crude oils and petroleum products. The emphasis of the catalogue is upon oils which could potentially impact Canada's environment. Other oils which are unlikely to be of direct Canadian concern are also included because they have been well characterized and used in relevant studies. The properties listed for each oil are those which will provide an indication of a spilled oil's environmental behaviour and effects. The properties on which data is provided include API gravity, density, viscosity, interfacial tension, pour point, flash point, vapor pressure, volatility and component distribution, emulsion formation tendency and stability, weathering, dispersability, major hydrocarbon groups, aqueous solubility, toxicity, sulfur content, fire point, and wax content. Most of the chemical-physical properties listed in this catalogue were measured using standard tests. For certain properties, data are given at different temperatures and for different degrees of oil weathering. An oil's degree of weathering is expresed as the volume or weight percent evaporated from the fresh oil. Weathered oils used for testing were artificially weathered by gas stripping following the method of Mackay and Stiver. 140 refs

Flotation mechanisms of molybdenite fines by neutral oils

Science.gov (United States)

Lin, Qing-quan; Gu, Guo-hua; Wang, Hui; Liu, You-cai; Fu, Jian-gang; Wang, Chong-qing

2018-01-01

The flotation mechanisms of molybdenite fines by neutral oils were investigated through microflotation test, turbidity measurements, infrared spectroscopy, and interfacial interaction calculations. The results of the flotation test show that at pH 2-11, the floatability of molybdenite fines in the presence of transformer oil is markedly better than that in the presence of kerosene and diesel oil. The addition of transformer oil, which enhances the floatability of molybdenite fines, promotes the aggregation of molybdenite particles. Fourier transform infrared measurements illustrate that physical interaction dominates the adsorption mechanism of neutral oil on molybdenite. Interfacial interaction calculations indicate that hydrophobic attraction is the crucial force that acts among the oil collector, water, and molybdenite. Strong hydrophobic attraction between the oily collector and water provides the strong dispersion capability of the collector in water. Furthermore, the dispersion capability of the collector, not the interaction strength between the oily collectors and molybdenite, has a highly significant role in the flotation system of molybdenite fines. Our findings provide insights into the mechanism of molybdenite flotation.

Flow behavior of N2 huff and puff process for enhanced oil recovery in tight oil reservoirs.

Science.gov (United States)

Lu, Teng; Li, Zhaomin; Li, Jian; Hou, Dawei; Zhang, Dingyong

2017-11-16

In the present work, the potential of N 2 huff and puff process to enhance the recovery of tight oil reservoir was evaluated. N 2 huff and puff experiments were performed in micromodels and cores to investigate the flow behaviors of different cycles. The results showed that, in the first cycle, N 2 was dispersed in the oil, forming the foamy oil flow. In the second cycle, the dispersed gas bubbles gradually coalesced into the continuous gas phase. In the third cycle, N 2 was produced in the form of continuous gas phase. The results from the coreflood tests showed that, the primary recovery was only 5.32%, while the recoveries for the three N 2 huff and puff cycles were 15.1%, 8.53% and 3.22%, respectively.The recovery and the pressure gradient in the first cycle were high. With the increase of huff and puff cycles, and the oil recovery and the pressure gradient rapidly decreased. The oil recovery of N 2 huff and puff has been found to increase as the N 2 injection pressure and the soaking time increased. These results showed that, the properly designed and controlled N 2 huff and puff process can lead to enhanced recovery of tight oil reservoirs.

Novel insight into the role of heterotrophic dinoflagellates in the fate of crude oil in the sea

DEFF Research Database (Denmark)

Almeda, Rodrigo; Connelly, Tara L.; Buskey, Edward J.

2014-01-01

Although planktonic protozoans are likely to interact with dispersed crude oil after a spill, protozoan-mediated processes affecting crude oil pollution in the sea are still not well known. Here, we present the first evidence of ingestion and defecation of physically or chemically dispersed crude...... to 0.37 mu g-oil mg-C-dino (-1) d(-1), which could represent similar to 17% to 100% of dispersed oil in surface waters when heterotrophic dinoflagellates are abundant or bloom. Egestion of faecal pellets containing crude oil by heterotrophic dinoflagellates could contribute to the sinking and flux...... of toxic petroleum hydrocarbons in coastal waters. Our study indicates that crude oil ingestion by heterotrophic dinoflagellates is a noteworthy route by which petroleum enters marine food webs and a previously overlooked biological process influencing the fate of crude oil in the sea after spills....

Self-propelled oil droplets consuming "fuel" surfactant

DEFF Research Database (Denmark)

Toyota, Taro; Maru, Naoto; Hanczyc, Martin M

2009-01-01

A micrometer-sized oil droplet of 4-octylaniline containing 5 mol % of an amphiphilic catalyst exhibited a self-propelled motion, producing tiny oil droplets, in an aqueous dispersion of an amphiphilic precursor of 4-octylaniline. The tiny droplets on the surface of the self-propelled droplet wer...

The deepwater horizon oil spill coast guard cohort study: A cross-sectional study of acute respiratory health symptoms.

Science.gov (United States)

Alexander, Melannie; Engel, Lawrence S; Olaiya, Nathan; Wang, Li; Barrett, John; Weems, Laura; Schwartz, Erica G; Rusiecki, Jennifer A

2018-04-01

Over 8500 United States Coast Guard (USCG) personnel were deployed in response to the Deepwater Horizon (DWH) oil spill; however, human respiratory effects as a result of spill-related exposures are relatively unknown. USCG personnel who responded to the DWH oil spill were queried via survey on exposures to crude oil and oil dispersant, and acute respiratory symptoms experienced during deployment. Adjusted log binomial regressions were used to calculate prevalence ratios (PRs) and 95% confidence intervals (CI), investigating the associations between oil spill exposures and respiratory symptoms. 4855 USCG personnel completed the survey. More than half (54.6%) and almost one-fourth (22.0%) of responders were exposed to crude oil and oil dispersants, respectively. Coughing was the most prevalent symptom (19.4%), followed by shortness of breath (5.5%), and wheezing (3.6%). Adjusted analyses showed an exposure-response relationship between increasing deployment duration and likelihood of coughing, shortness of breath, and wheezing in the pre-capping period. A similar pattern was observed in the post-capping period for coughing and wheezing. Adjusted analyses revealed increased PRs for coughing (PR=1.92), shortness of breath (PR=2.60), and wheezing (PR=2.68) for any oil exposure. Increasing frequency of inhalation of oil was associated with increased likelihood of all three respiratory symptoms. A similar pattern was observed for contact with oil dispersants for coughing and shortness of breath. The combination of both oil and oil dispersants presented associations that were much greater in magnitude than oil alone for coughing (PR=2.72), shortness of breath (PR=4.65), and wheezing (PR=5.06). Results from the present study suggested strong relationships between oil and oil dispersant exposures and acute respiratory symptoms among disaster responders. Future prospective studies will be needed to confirm these findings. Copyright © 2017 Elsevier Inc. All rights reserved.

Simultaneous determination of six synthetic phenolic antioxidants in edible oils using dispersive liquid-liquid microextraction followed by high-performance liquid chromatography with diode array detection.

Science.gov (United States)

Xu, Shuangjiao; Liu, Liangliang; Wang, Yanqin; Zhou, Dayun; Kuang, Meng; Fang, Dan; Yang, Weihua; Wei, Shoujun; Xiao, Aiping; Ma, Lei

2016-08-01

A simple, rapid, organic-solvent- and sample-saving pretreatment technique, called dispersive liquid-liquid microextraction, was developed for the determination of six synthetic phenolic antioxidants from edible oils before high-performance liquid chromatography with diode array detection. The entire procedure was composed of a two-step microextraction and a centrifugal process and could be finished in about 5 min, only consuming only 25 mg of sample and 1 mL of the organic solvent for each extraction. The influences of several important parameters on the microextraction efficiency were thoroughly investigated. Recovery assays for oil samples were spiked at three concentration levels, 50, 100 and 200 mg/kg, and provided recoveries in the 86.3-102.5% range with a relative standard deviation below 3.5%. The intra-day and inter-day precisions for the analysis were less than 3.8%. The proposed method was successfully applied for the determination of synthetic phenolic antioxidants in different oil samples, and satisfactory results were obtained. Thus, the developed method represents a viable alternative for the quality control of synthetic phenolic antioxidant concentrations in edible oils. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

On-land and offshore testing of a new helicopter bucket for dispersant application - response 3000D

International Nuclear Information System (INIS)

Brandvik, P. J.; Lewis, A.; Daling, P. S.; Strom-Kristiansen, T.; Larsen, E.

1997-01-01

Development of a new helicopter bucket for dispersant applications to serve the dispersant spraying needs of Norwegian oil companies was described. Testing two existing helicopter buckets and practical experience with firefighting helicopter operations provided the foundations for this developmental experiment, combined with the dispersant applications experience of SINTEF. The newly designed bucket, 3000D, has two dispersant spray systems (high and low flow rates) and a large capacity ( three cu m). It is capable of direct filling of dispersant via a suction hose while the helicopter is hovering and is equipped for remote control of all functions. It is robustly designed for use under harsh offshore conditions in the North Sea. The bucket has been subjected to extensive testing on land and offshore with experimental oil slicks. The results were fully satisfactory. 9 refs., 1 tab., 13 figs

Simultaneous Determination of Perfluorinated Compounds in Edible Oil by Gel-Permeation Chromatography Combined with Dispersive Solid-Phase Extraction and Liquid Chromatography-Tandem Mass Spectrometry.

Science.gov (United States)

Yang, Lili; Jin, Fen; Zhang, Peng; Zhang, Yanxin; Wang, Jian; Shao, Hua; Jin, Maojun; Wang, Shanshan; Zheng, Lufei; Wang, Jing

2015-09-30

A simple analytical method was developed for the simultaneous analysis of 18 perfluorinated compounds (PFCs) in edible oil. The target compounds were extracted by acetonitrile, purified by gel permeation chromatography (GPC) and dispersive solid-phase extraction (DSPE) using graphitized carbon black (GCB) and octadecyl (C18), and analyzed by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ES-MS/MS) in negative ion mode. Recovery studies were performed at three fortification levels. The average recoveries of all target PFCs ranged from 60 to 129%, with an acceptable relative standard deviation (RSD) (1-20%, n = 3). The method detection limits (MDLs) ranged from 0.004 to 0.4 μg/kg, which was significantly improved compared with the existing liquid-liquid extraction and cleanup method. The method was successfully applied for the analysis of all target PFCs in edible oil samples collected from markets in Beijing, China, and the results revealed that C6-C10 perfluorocarboxylic acid (PFCAs) and C7 perfluorosulfonic acid PFSAs were the major PFCs detected in oil samples.

OSCAR2000 : a multi-component 3-dimensional oil spill contingency and response model

International Nuclear Information System (INIS)

Reed, M.; Daling, P.S.; Brakstad, O.G.; Singsaas, I.; Faksness, L.-G.; Hetland, B.; Ekrol, N.

2000-01-01

Researchers at SINTEF in Norway have studied the weathering of surface oil. They developed a realistic model to analyze alternative spill response strategies. The model represented the formation and composition of the water-accommodated fraction (WAF) of oil for both treated and untreated oil spills. As many as 25 components, pseudo-components, or metabolites were allowed for the specification of oil. Calculations effected using OSCAR were verified in great detail on numerous occasions. The model made it possible to determine rather realistically the dissolution, transformation, and toxicology of dispersed oil clouds, as well as evaporation, emulsification, and natural dispersion. OSCAR comprised a data-based oil weathering model, a three-dimensional oil trajectory and chemical fates model, an oil spill combat model, exposure models for birds, marine mammals, fish and ichthyoplankton. 17 refs., 1 tab., 11 figs

Novel insight into the role of heterotrophic dinoflagellates in the fate of crude oil in the sea

Science.gov (United States)

Almeda, Rodrigo; Connelly, Tara L.; Buskey, Edward J.

2014-12-01

Although planktonic protozoans are likely to interact with dispersed crude oil after a spill, protozoan-mediated processes affecting crude oil pollution in the sea are still not well known. Here, we present the first evidence of ingestion and defecation of physically or chemically dispersed crude oil droplets (1-86 μm in diameter) by heterotrophic dinoflagellates, major components of marine planktonic food webs. At a crude oil concentration commonly found after an oil spill (1 μL L-1), the heterotrophic dinoflagellates Noctiluca scintillans and Gyrodinium spirale grew and ingested ~0.37 μg-oil μg-Cdino-1 d-1, which could represent ~17% to 100% of dispersed oil in surface waters when heterotrophic dinoflagellates are abundant or bloom. Egestion of faecal pellets containing crude oil by heterotrophic dinoflagellates could contribute to the sinking and flux of toxic petroleum hydrocarbons in coastal waters. Our study indicates that crude oil ingestion by heterotrophic dinoflagellates is a noteworthy route by which petroleum enters marine food webs and a previously overlooked biological process influencing the fate of crude oil in the sea after spills.

A hybrid model to predict the entrainment and subsurface transport of oil

International Nuclear Information System (INIS)

Spaulding, M.L.; Odulo, A.; Kolluru, V.S.

1992-01-01

The entrainment of surface oil into the water column and its subsequent subsurface transport and dispersion are predicted by a hybrid analytic-numerical solution to the advective diffusion equation. Total oil or selected hydrocarbon component concentrations in the water column are predicted. Assuming that the principal mechanism for entrainment is due to breaking waves, the oil entrainment rate is specified using the empirically based algorithm of Delvigne and Sweeney (1988). The subsurface transport model explicitly accounts for buoyant forces on dispersed oil by droplet size. Application of the model to an analytic test case and several hypothetical scenarios illustrates the model's utility. 35 refs., 8 figs., 2 tabs

Evaluation, au laboratoire, du pouvoir dispersant d'une huile pour moteurs à essence et relation avec les résultats obtenus dans la séquence VE Laboratory Evaluation of the Dispersive Power of Gazoline Engines Oils and Relation with Sequence Ve Test Results

Directory of Open Access Journals (Sweden)

Hipeaux J. C.

2006-11-01

� 200°C, à l'aide de boues provenant d'une huile ayant été préalablement vieillie sur moteur Ford Pinto 2,3 l et d'eau (tableaux 4 et 6, fig. 3. On trace alors la courbe Mérite dispersant résiduel(MDR en fonction du temps d'oxydation (fig. 5 et 12. Cette courbe a la même allure que celle décrite dans la séquence VE (fig. 1. Le tracé des courbes MDR en fonction de la cotation moteur moyenne en boues VE (Average Engine Sludge Deposit (AES permet de discriminer clairement les huiles bonnes ou mauvaises en Séquence VE. À partir de 96 h d'oxydation, dans l'essai OXYDISP (fig. 9 et de 48 h dans l'essai POTDISP (fig. 14, nous sommes en présence de deux familles de produits : les produits qui conservent leur MDR et qui obtiennent un mérite boueségal ou supérieur à 9, dans la Séquence VE et les produits qui perdent leur MDR et qui ont tous des mérites inférieurs à 9 dans la même séquence. Les méthodes OXYDISP et POTDISP permettent également de différencier des huiles de niveaux API différents (niveaux SE, SF et SG (fig. 16 et 17. Evaluating the dispersive power of an oil for gasoline engines is included in international specifications such as the ones issued by the Committee of Common Market Automobile Constructors (CCMC and the American Petroleum Institute (API. This evaluation is the result of lengthy, severe and costly testing in engines on a test bench. These tests are performed in Mercedes M102E (CCMC levels G4 and G5 and Ford Pinto 2. 31 (API levels SG and SH engines. The cost of these tests requires the laboratory use of reliable preselection tests. The more often used test for evaluating the dispersive power of a motor oil is the spottest. It is performed in the presence of pollutants coming from an used Diesel motor oil (Tables 1 and 4, Fig. 2. However, some additive technologies that give good results for this test give poor results during engine testing (Table 2. During the VE Sequence lasting for 288 hr, the oil is subjected to different

Mathematical modelling of oil spill fate and transport in the marine environment incorporating biodegradation kinetics of oil droplets

Science.gov (United States)

Spanoudaki, Katerina

2016-04-01

Oil biodegradation by native bacteria is one of the most important natural processes that can attenuate the environmental impacts of marine oil spills. However, very few numerical models of oil spill fate and transport include biodegradation kinetics of spilled oil. Furthermore, in models where biodegradation is included amongst the oil transformation processes simulated, it is mostly represented as a first order decay process neglecting the effect of several important parameters that can limit biodegradation rate, such as oil composition and oil droplets-water interface. To this end, the open source numerical model MEDSKIL-II, which simulates oil spill fate and transport in the marine environment, has been modified to include biodegradation kinetics of oil droplets dispersed in the water column. MEDSLIK-II predicts the transport and weathering of oil spills following a Lagrangian approach for the solution of the advection-diffusion equation. Transport is governed by the 3D sea currents and wave field provided by ocean circulation models. In addition to advective and diffusive displacements, the model simulates several physical and chemical processes that transform the oil (evaporation, emulsification, dispersion in the water column, adhesion to coast). The fate algorithms employed in MEDSLIK-II consider the oil as a uniform substance whose properties change as the slick weathers, an approach that can lead to reduced accuracy, especially in the estimation of oil evaporation and biodegradation. Therefore MEDSLIK-II has been modified by adopting the "pseudo-component" approach for simulating weathering processes. Spilled oil is modelled as a relatively small number of discrete, non-interacting components (pseudo-components). Chemicals in the oil mixture are grouped by physical-chemical properties and the resulting pseudo-component behaves as if it were a single substance with characteristics typical of the chemical group. The fate (evaporation, dispersion

Bacterial Community Response in Deep Faroe-Shetland Channel Sediments Following Hydrocarbon Entrainment With and Without Dispersant Addition

Directory of Open Access Journals (Sweden)

Luis J. Perez Calderon

2018-05-01

Full Text Available Deep sea oil exploration is increasing and presents environmental challenges for deep ocean ecosystems. Marine oil spills often result in contamination of sediments with oil; following the Deepwater Horizon (DwH disaster up to 31% of the released oil entrained in the water column was deposited as oily residues on the seabed. Although the aftermath of DwH was studied intensely, lessons learned may not be directly transferable to other deep-sea hydrocarbon exploration areas, such as the Faroe-Shetland Channel (FSC which comprises cold temperatures and a unique hydrodynamic regime. Here, transport of hydrocarbons into deep FSC sediments, subsequent responses in benthic microbial populations and effects of dispersant application on hydrocarbon fate and microbial communities were investigated. Sediments from 1,000 m in the FSC were incubated at 0°C for 71 days after addition of a 20-hydrocarbon component oil-sediment aggregate. Dispersant was added periodically from day 4. An additional set of cores using sterilized and homogenized sediment was analyzed to evaluate the effects of sediment matrix modification on hydrocarbon entrainment. Sediment layers were independently analyzed for hydrocarbon content by gas chromatography with flame ionization detection and modeled with linear mixed effects models. Oil was entrained over 4 cm deep into FSC sediments after 42 days and dispersant effectiveness on hydrocarbon removal from sediment to the water column decreased with time. Sterilizing and homogenizing sediment resulted in hydrocarbon transport over 4 cm into sediments after 7 days. Significant shifts in bacterial populations were observed (DGGE profiling in response to hydrocarbon exposure after 42 days and below 2 cm deep. Dispersant application resulted in an accelerated and modified shift in bacterial communities. Bacterial 16S rRNA gene sequencing of oiled sediments revealed dominance of Colwellia and of Fusibacter when dispersant was applied over

A 'Puff' dispersion model for routine and accidental releases

International Nuclear Information System (INIS)

Grsic, Z.; Rajkovic, B.; Milutinovic, P.

1999-01-01

A Puff dispersion model for accidental or routine releases is presented. This model was used as a constitutive part of an automatic meteorological station.All measured quantities are continuously displayed on PC monitor in a digital and graphical form, they are averaging every 10 minutes and sending to the civil information center of Belgrade. In the paper simulation of a pollutant plume dispersion from The oil refinery 'Pancevo', on April 18 th 1999 is presented. (author)

Investigation and development of heavy oil upgrading catalysts. 3

Energy Technology Data Exchange (ETDEWEB)

Lee, D.K.; Lee, I.C.; Yoon, W.L.; Lee, H.T.; Chung, H.; Hwang, Y.J.; Park, S.H. [Korea Inst. of Energy Research, Taejon (Korea, Republic of)

1995-12-01

This study aimed at the domestic development of HDS catalysts which are most fundamental and wide-used in the petroleum refinery. In this year, some experimental works were conducted for developing the effective utilization technology of the novel dispersed-catalysts in the hydro-desulfurization of heavy oils, and improving the reaction performance of alumina-supported Mo-based hydro-treating catalysts conventionally used in most of refineries. First, it was experimentally proved that the dispersed catalysts of Co-Mo could be employed for the hydro-desulfurization of a heavy atmospheric residual oil excluding the catalyst deactivation. The utilization of a carbon-expanded reactor in combination with this dispersed catalyst system exhibited an enhanced reaction performance and provided an efficient way for the separation and recovery of the dispersed catalytic component from oils. Second, the tungsten-incorporated WCoMo/{gamma}-Al{sub 2}O{sub 3} catalyst revealed the improved catalytic performance in the various hydro-treating reactions and in the initial deactivation rates for the high pressure hydro-treatment of a heavy oil as compared with the commercial CoMo/{gamma}-Al{sub 2}O{sub 3} catalyst. This new experimental finding for the promoting role of the monomeric WO{sub 3} species in CoMo/{gamma}-Al{sub 2}O{sub 3} catalyst may be generally applicable to the Mo-based alumina-sulfide phase, higher catalytic activity, and more extended service life. (author). 101 refs., 33 figs., 18 tabs.

Effect of capillary number on the oil recovery using oil-water emulsion injection in core flooding experiments

Energy Technology Data Exchange (ETDEWEB)

Guillen Nunez, Victor Raul; Carvalho, Marcio da Silveira [Pontifical Catholic University of Rio de Janeiro (PUC-Rio), RJ (Brazil). Dept. of Mechanical Engineering], E-mail: msn@puc-rio.br; Basante, Vladimir Alvarado [University of Wyoming, Laramie, WY (United States). Dept. of Chemical/Petroleum Engineering], E-mail: valvard@uwyo.edu

2010-07-01

The Water injection flooding is a common method to improve reservoir sweep and pressure maintenance. The heavy-oil-recovery efficiency is in part limited by the high water-to-oil mobility ratio. Several enhanced oil recovery methods are being developed as more efficient alternatives to water flooding. Dispersion injection, in particular oil-water emulsion injection, has been tried with relative success as an enhanced oil recovery method, but the technique is not fully developed or understood. If emulsion injection proves to be an effective EOR method, its use would bring the added benefit of disposing produced water with small oil content that could be modified to serve as the injected oil-water emulsion. The use of such methods requires a detailed analysis of the different flow regimes of emulsions through the porous space of a reservoir rock. If the drop size of the disperse phase is of the same order of magnitude as the pore size, the drops may agglomerate and partially block water flow through pores. This flow regime may be used to control the mobility of the injected liquid, leading to higher recovery factor. We have shown in recent experiments of oil displacement in a sandstone core that, the oil recovery factor could be raised from approximately 40 %, obtained with water injection only, up to approximately 75 % by alternating water and emulsion injection. Although these results clearly show the improvement in the recovery factor, the mechanisms responsible for the phenomenon have not been clearly elucidated. In this work, two sandstone cores were used to demonstrate the effect of flow rate (capillary number) on the mobility control by emulsion injection. Figure 1 shows a schematic representation of the experiment set-up. The experiments show that raising the flow rate by a factor of 10 (0.03 ml/min to 0.3 ml/min), the oil recovered factor decreases considerably. (author)

Hydraulic washing removal efficiencies of Orimulsion from rock surfaces

International Nuclear Information System (INIS)

Harper, J.R.; Ward, S.; Sergy, G.

2002-01-01

Orimulsion is a fuel alternative composed of 70 per cent bitumen in 30 per cent water. It is shipped from Venezuela to New Brunswick where it is used as fuel oil for power plants. While there have not been any major spills of Orimulsion, it is recognized that very little is known regarding the dispersal and weathering processes of Orimulsion, or the behaviour and cleanup of the product on both rocky and course sediment shorelines. For that reason, this study was conducted to determine the efficiency of hydraulic washing under different water temperatures and pressures to remove bitumen from rocky shorelines. The results of the study make it possible to assess the physical effectiveness of the method and to determine the range of effective operational parameters. The coating protocol was refined to create uniform coating of both dispersed and coalesced bitumen of rock surfaces. The use of a chemical agent for enhancing removal efficiency was also assessed. Orimulsion could reach shorelines as low concentration dispersions of bitumen particles suspended in a water column, or as a high concentration mixture of bitumen, water and air. Granite tiles were coated with uniform coatings of both dispersed and coalesced bitumen. They were then washed under different pressures, temperatures and other treatments. Temperatures of more than 40 degrees C and pressures of more than 76 kPa were needed to effectively remove the bitumen coatings. Weathering significantly increased coating tenacity for dispersed coatings, but did not affect coalesced coating tenacity. Immediate washing was found to be very effective for removing dispersed coating, but not for coalesced coating. Coating tenacity was also affected by submergence times. Pre-treatment of the coating with a dispersion called Corexit significantly improved the removal efficiencies of dispersed coatings, but not coalesced coatings. 6 refs., 10 tabs., 5 figs

Production of Flocculants, Adsorbents, and Dispersants from Lignin.

Science.gov (United States)

Chen, Jiachuan; Eraghi Kazzaz, Armin; AlipoorMazandarani, Niloofar; Hosseinpour Feizi, Zahra; Fatehi, Pedram

2018-04-10

Currently, lignin is mainly produced in pulping processes, but it is considered as an under-utilized chemical since it is being mainly used as a fuel source. Lignin contains many hydroxyl groups that can participate in chemical reactions to produce value-added products. Flocculants, adsorbents, and dispersants have a wide range of applications in industry, but they are mainly oil-based chemicals and expensive. This paper reviews the pathways to produce water soluble lignin-based flocculants, adsorbents, and dispersants. It provides information on the recent progress in the possible use of these lignin-based flocculants, adsorbents, and dispersants. It also critically discusses the advantages and disadvantages of various approaches to produce such products. The challenges present in the production of lignin-based flocculants, adsorbents, and dispersants and possible scenarios to overcome these challenges for commercial use of these products in industry are discussed.

Role of EPS, Dispersant and Nutrients on the Microbial Response and MOS Formation in the Subarctic Northeast Atlantic

Directory of Open Access Journals (Sweden)

Tony Gutierrez

2017-04-01

Full Text Available In this study we report the formation of marine oil snow (MOS, its associated microbial community, the factors influencing its formation, and the microbial response to crude oil in surface waters of the Faroe-Shetland Channel (FSC. The FSC is a subarctic region that is hydrodynamically complex located in the northeast Atlantic where oil extraction is currently occurring and where exploration is likely to expand into its deeper waters (>500 m. A major oil spill in this region may mirror the aftermath that ensued following the Deepwater Horizon (DWH blowout in the Gulf of Mexico, where the massive influx of Macondo crude oil triggered the formation of copious quantities of rapidly sinking MOS and successional blooms of opportunistic oil-degrading bacteria. In laboratory experiments, we simulated environmental conditions in sea surface waters of the FSC using water collected from this site during the winter of 2015. We demonstrated that the presence of dispersant triggers the formation of MOS, and that nutrient amendments magnify this. Illumina MiSeq sequencing revealed the enrichment on MOS of associated oil-degrading (Cycloclasticus, Thalassolituus, Marinobacter and EPS-producing (Halomonas, Pseudoalteromonas, Alteromonas bacteria, and included major representation by Psychrobacter and Cobetia with putative oil-degrading/EPS-producing qualities. The formation of marine snow, in the absence of crude oil and dispersant, in seawater amended with nutrients alone indicated that the de novo synthesis of bacterial EPS is a key factor in MOS formation, and the glycoprotein composition of the MOS aggregates confirmed that its amorphous biopolymeric matrix was of microbial (likely bacterial origin. The presence of dispersants and crude oil with/without nutrients resulted in distinct microbial responses marked by intermittent, and in some cases short-lived, blooms of opportunistic heterotrophs, principally obligate hydrocarbonoclastic (Alcanivorax

Geochemical dispersion associated with uranium deposits in sandstone roll front type and its relationship to the Orinoco Oil Belt, Venezuela

International Nuclear Information System (INIS)

Manrique, J.

2014-01-01

In Venezuela, there is a potential for the formation of uranium deposits in areas such as the Guiana Shield, the south of the Eastern Basin, the Andes and the massif of Baúl, among other areas. Especially great interest is the exploration of uranium redox interface type (roll front), in areas such as the southern part of the Orinoco Oil Belt, north and northwest of the Guiana Shield, where groundwater uranium collecting the weathering shield flowing northward in the sandstones and mudstones of the Cretaceous to Quaternary formations, which constitute the southern boundary of the Eastern basin Venezuela. The presence of gas, extra-heavy crude oil, bitumen and lignite of the Orinoco Oil Belt can be an effective barrier for uranium in solution, which may have precipitated at the redox interface of this groundwater. This process certainly was more effective before the Orinoco river take its course to the east and the waters of small rivers and large draining shield contributed to uranium aquifers became more deep north. This work was based on a qualitative model describing geochemical dispersion associated with uranium deposits in sandstone, roll front type, which indicates that the daughter isotopes "2"3"8U, which can migrate extensively are: "2"2"2Rn, "4He, and in a smaller proportion: "2"2"6Ra and "2"2"2Rn daughters ("2"1"4Bi, "2"1"0Pb). The main exploration methods were established, which can be applied in areas of the Orinoco Oil Belt, north of the Guiana Shield, and areas west of this, among the most important are: soil measurements of radon and helium near faults, sampling soils with gamma spectrometry analysis, log interpretation of oil wells in the area of interest to establish gamma – lithological anomalies, ground water analysis of uranium, radon, radium, helium, vanadium, selenium, molybdenum, analysis of samples oil drilling cores to locate anomalous stratigraphic levels. This research will provide the basis to establish methodologies for uraniferous

Updating the U.S. SMART dispersant efficacy monitoring protocol

International Nuclear Information System (INIS)

Trudel, K.; Belore, R.; VanHaverbeke, M.; Mullin, J.

2009-01-01

The Special Monitoring of Applied Response Technologies (SMART) is a written dispersant effectiveness monitoring protocol developed in the United States in the mid 1990s. It has been the subject of considerable review and research since its development. This paper reported on the 2007-2008 review of the SMART dispersant effectiveness monitoring protocol which involved the following 3 tasks: (1) stakeholders reviewed their experience with SMART and identified the key deficiencies in the current protocol, (2) the SMART monitoring experience gathered during dispersant effectiveness testing at the Ohmsett National Oil Spill Response Test Facility was reviewed to evaluate the usefulness of existing SMART decision criteria, (3) available commercial off-the-shelf instruments (COTS) were surveyed to identify the instruments that might be more effective or simpler to use than those presently in use. The review concluded that the three-tiered approach in SMART was appropriate, but better guidance was needed for users. In addition, the fluorometer historically used for monitoring of dispersed oil was found to have several operating challenges and should be replaced with more modern equipment. It was recommended that all U.S. government sponsored monitoring teams work with identical instruments and operating protocols. The COTS survey identified 6 potentially suitable submersible and field-portable fluorometers and three particle-size analyzers. 26 refs., 5 tabs., 1 fig

A re-circulated toxicity exposure chamber to evaluate hydrocarbon dispersions

International Nuclear Information System (INIS)

Fuller, C.B.; Bonner, J.S.; Bujnoch, J.D.; Ussery, S.F.; Arrambide, G.; Sterling, M.C.

2002-01-01

Traditional toxicology methods are not suitable for evaluating chemically dispersed oil which exists mostly as a colloidal suspension and as dissolved fractions. A new toxicity exposure chamber was designed with separate chambers for scaled mixing and organism exposure. The design of the chamber incorporates continuous recirculation between the mixing and exposure chamber and an upward flow in the exposure chamber. The toxicity exposure system incorporates scalable and quantitative mixing inputs with real time particle size analysis and traditional petrochemistry methods to characterize the exposure regime. Changes in dispersion were successfully translated to the organism exposure regime. The study determined the petroleum toxicity with a juvenile marine test species. Low control mortality demonstrated the usefulness of the method for testing toxicity of colloidal oil suspensions. 20 refs., 1 tab., 4 figs

Remote sensing of coastal fronts and their effects on oil dispersion

Energy Technology Data Exchange (ETDEWEB)

Klemas, V

1980-01-01

The use of remote sensing techniques to determine the properties of coastal and estuarine fronts, which represent regions of discontinuities and high gradients in ocean physical parameters such as velocity and density, and to assess the influence of such fronts on oil pollutants is discussed. Results of an aircraft and boat verification study of an oil drift and spread model in Delaware Bay are indicated which illustrate the tendency of oil slicks to be attracted to frontal regions, where a denser fluid underlies a lighter fluid giving rise to an inclined interface with convergence zones. Landsat imagery of the bay acquired in order to incorporate frontal information into the interactive computer model is then presented which allows the locations of coastal fronts to be charted throughout a tidal cycle. It is noted that satellite observations of flood-associated fronts on the New Jersey side of the bay and ebb-associated fronts on the Delaware side agree with boat measurements and model predictions, and that the remote tracking of fronts by aircraft and satellites will aid in oil slick clean-up operations.

Automatic Data Collection Design for Real-Time Detection of Oil ...

African Journals Online (AJOL)

Such disasters can occur at any point within the entire oil-pipeline topology, which is geographically dispersed across the country spanning from the extreme south-south through south-east and south-west to the north central. A major cause of oil spillage disaster is oil-pipeline vandalism, which has recently become one of ...

Anomalous dispersion due to hydrocarbons: The secret of reservoir geophysics?

Science.gov (United States)

Brown, R.L.

2009-01-01

When P- and S-waves travel through porous sandstone saturated with hydrocarbons, a bit of magic happens to make the velocities of these waves more frequency-dependent (dispersive) than when the formation is saturated with brine. This article explores the utility of the anomalous dispersion in finding more oil and gas, as well as giving a possible explanation about the effect of hydrocarbons upon the capillary forces in the formation. ?? 2009 Society of Exploration Geophysicists.

Evaluation of hovercraft for dispersant application

Energy Technology Data Exchange (ETDEWEB)

Dickens, D; Belore, R; Buist, I; Humphrey, B

1988-01-01

A series of field trials were carried out in Vancouver, Canada in July and August 1986 to determine whether or not hovercraft should be considered for dispersant application. Questions are: the ability of the hovercraft to ''fly'' over an oil slick at high speed without displacing the oil out of the path, the potential for using the hovercraft to impart vertical mixing energy into the water column to aid in the dispersant process and, the ability to mount a suitable spray boom and obtain a uniform spray pattern across the swath width. The field trials and subsequent interpretation of results provide positive answers to the first and second question. The question of mixing energy requires some qualification. The hovercraft contributes considerable mixing energy to the immediate water surface through air entrainment but this effect is short lived and there does not appear to be significant long term vertical mixing in the hovercraft wake. Recommendations are made for operating procedures and boom mounting which should ensure a uniform drop size and dose rate across a swath up to 18 m. The cushion air escaping from around the craft perimeter is not an important factor in adversly affecting the dispersant spray pattern. Depending on the type of machine available, hovcercraft have the capability of treating up to a 1km/sup 2/ slick between loads, at average speeds in the 15 to 25 knot range. The inherent advantages of high transit speed to the site (up to 45 Knots), amphibious operation (i.e. not draft limited) and lack of ceiling or visibility restrictions provide hovercarft with unique capabilities in the dispersant application role. Two patents relating to the process have been abstracted. Appendix B gives the sprecifications of two different models of hovercrafts. 14 refs., 29 figs., 6 tabs.

The Optimization of the Oiling Bath Cosmetic Composition Containing Rapeseed Phospholipids and Grapeseed Oil by the Full Factorial Design

Directory of Open Access Journals (Sweden)

Michał Górecki

2015-04-01

Full Text Available The proper condition of hydrolipid mantle and the stratum corneum intercellular matrix determines effective protection against transepidermal water loss (TEWL. Some chemicals, improper use of cosmetics, poor hygiene, old age and some diseases causes disorder in the mentioned structures and leads to TEWL increase. The aim of this study was to obtain the optimal formulation composition of an oiling bath cosmetic based on rapeseed phospholipids and vegetable oil with high content of polyunsaturated fatty acids. In this work, the composition of oiling bath form was calculated and the degree of oil dispersion after mixing the bath preparation with water was selected as the objective function in the optimizing procedure. The full factorial design 23 in the study was used. The concentrations of rapeseed lecithin ethanol soluble fraction (LESF, alcohol (E and non-ionic emulsifier (P were optimized. Based on the calculations from our results, the optimal composition of oiling bath cosmetic was: L (LESF 5.0 g, E (anhydrous ethanol 20.0 g and P (Polysorbate 85 1.5 g. The optimization procedure used in the study allowed to obtain the oiling bath cosmetic which gives above 60% higher emulsion dispersion degree 5.001 × 10−5 cm−1 compared to the initial formulation composition with the 3.096 × 10−5 cm−1.

Production of Flocculants, Adsorbents, and Dispersants from Lignin

Directory of Open Access Journals (Sweden)

Jiachuan Chen

2018-04-01

Full Text Available Currently, lignin is mainly produced in pulping processes, but it is considered as an under-utilized chemical since it is being mainly used as a fuel source. Lignin contains many hydroxyl groups that can participate in chemical reactions to produce value-added products. Flocculants, adsorbents, and dispersants have a wide range of applications in industry, but they are mainly oil-based chemicals and expensive. This paper reviews the pathways to produce water soluble lignin-based flocculants, adsorbents, and dispersants. It provides information on the recent progress in the possible use of these lignin-based flocculants, adsorbents, and dispersants. It also critically discusses the advantages and disadvantages of various approaches to produce such products. The challenges present in the production of lignin-based flocculants, adsorbents, and dispersants and possible scenarios to overcome these challenges for commercial use of these products in industry are discussed.

Influence sur les imbrûlés solides de composés métalliques particuliers et du taux de dispersion des asphaltènes dans les fuels lourds Influence of Unburned Solids Made of Unusual Metal Compounds and of the Asphaltene Dispersion Rate in Heavy Fuel Oils

Directory of Open Access Journals (Sweden)

Audibert F.

2006-11-01

Full Text Available La diversité croissante des origines de bruts a conduit, en combustion, a prendre en considération dans les modèles la teneur en métaux en plus du carbone Conradson ou des asphaltènes au C7 dans les fuels lourds. De tels modèles ont été développés par Exxon (1979 et Shell (1981 notamment. Des travaux récents faits à l'Institut Français du Pétrole (IFP sur une chaudière de 2 MW ont montré l'influence de composés métalliques particuliers présents dans le fuel oil sous forme de sulfures imprégnant des particules de carbone poreux. Ces microparticules peuvent être générées lorsque l'on applique des conditions opératoires sévères à la viscoréduction de fuels résiduaires en présence d'hydrogène et d'un catalyseur approprié. Ces microparticules se sont révélées très actives en combustion et ont montré que la concentration du métal n'était pas le seul facteur à prendre en considération mais que la manière dont il était combiné pouvait être prépondérante. Pour étendre le domaine d'application des modèles, d'autres paramètres comme les conditions de fonctionnement de la chaudière et l'atomisation du fuel ont été pris en compte en plus des paramètres d'influence propres au fuel (travaux du Laboratoire Énergie du MIT publications 1986. En ce qui concerne la prédiction d'émissions particulaires une méthode complémentaire aux tests de résidu de Conradson et d'insolubilité à l'heptane normal a été appliquée à I'IFP dans le cadre d'un programme de valorisation des huiles lourdes en association avec les compagnies pétrolières Elf et Total France. Cette méthode consiste à évaluer à la microscopie électronique par transmission le taux de dispersion des asphaltènes, selon une méthode développée par Total France (M. Peyrot. Il existe une relation entre ce taux de dispersion et l'émission particulaire. Ce phénomène a été nettement observé dans le cas de fuels lourds constitués par

A green deep eutectic solvent dispersive liquid-liquid micro-extraction (DES-DLLME) for the UHPLC-PDA determination of oxyprenylated phenylpropanoids in olive, soy, peanuts, corn, and sunflower oil.

Science.gov (United States)

Ferrone, Vincenzo; Genovese, Salvatore; Carlucci, Maura; Tiecco, Matteo; Germani, Raimondo; Preziuso, Francesca; Epifano, Francesco; Carlucci, Giuseppe; Taddeo, Vito Alessandro

2018-04-15

A green dispersive liquid-liquid microextraction (DLLME) using deep eutectic solvent (DES) as the extracting solvent has been developed and applied for the simultaneous quantification of ferulic acid, umbelliferone, boropinic acid, 7-isopentenyloxycoumarin, 4'-geranyloxyferulic acid (GOFA), and auraptene in some vegetable oils using ultra high performance liquid chromatography (UHPLC) with photodiode array detection (PDA). All parameters in the extraction step, including selection and loading of both extracting and dispersing solvents, amount of both extractant and disperser solvent were investigated and optimized. PhAA/TMG DES achieved higher recovery and enrichment factor compared to other DESs. The validated method showed good linearity with correlation coefficients, r 2 >0.9990 for all the analytes. Furthermore, this is the first time that eco-friendly solvents are used for the extraction of oxyprenylated phenylpropanoids and the corresponding extract analyzed with ultra high performance liquid chromatography with photodiode array detection. Copyright © 2017 Elsevier Ltd. All rights reserved.

A fundamental research for upgrading heavy oil using syngas as hydrogen source

Energy Technology Data Exchange (ETDEWEB)

Yan, D.; Yuan, M.; Sun, X.; Zhao, S. [China Univ. of Petroleum, Beijing (China). State Key Laboratory of Heavy Oil Processing

2006-07-01

The stock of heavy oil and residue from petroleum fractions has become more important as a component in supplying demands for fuel and petrochemical feeds. Finding economical means of upgrading heavy oils is extremely important in order to ensure future fuel supply. A number of new technologies for upgrading heavy oils have been evaluated, including residual fluid catalytic cracking (RFCC), hydrogenation, thermal conversion, and solvent deasphalting. However, the commercial application of such technologies is mainly constrained by the metal and residual carbon concentrations that are present in all heavy oils. Conventional technologies used to upgrade vacuum residue (VR) result in heavy coke formation, with a consequential reduction in the life of expensive, high-performance catalysts. The hydro upgrading process can significantly remove the concentration of heteroatom such as sulfur, nitrogen, and metals in the liquid products. This paper investigated upgrading of heavy oil using syngas as an alternative hydrogen source with a dispersed catalyst. The paper discussed the experiment with reference to the feedstock and catalyst precursors; finely dispersed catalysts preparation; experimental apparatus; experimental design and procedure; and analysis. The results were presented in terms of effects of catalyst dispersion; effect of hydro-upgrading heavy oil using syngas as alternative source; and effects of different catalysts on residue hydrocracking. Last, the paper discussed the properties of the hydrocracked oil treated with syngas. The study confirmed the effectiveness of the slurry bed hydrocracking catalyst using syngas as a hydrogen source. 23 refs., 8 tabs., 16 figs.

When oil spills emulsify

International Nuclear Information System (INIS)

Bobra, M.; Fingas, M.; Tennyson, E.

1992-01-01

Cleanup operations of oil spills must take into account the numerous detrimental effects attributable to the emulsification of spilled oil into a stable water-in-oil mousse. The incorporation of water greatly increases the volume of the polluted material. The viscous nature of mousse impedes the efficient operation of most mechanical recovery equipment and results in a cohesive slick that resists dispersion, both natural and artificial. The rate at which spilled oil emulsifies determines the effective window of opportunity for specific countermeasures. Much has been learned from previous studies on petroleum emulsification, but is still remain a poorly understood phenomenon. Although most crude oils can be emulsified, not all spills result in the formation of stable mousse. The formation of mousse results from a complex series of processes. Whether an oil will form mousse or not, and if so, at what rate, depends on an array of different factors including the properties of the oil and the prevailing environmental conditions. We need a greater understanding of the emulsification process to better predict the emulsification behavior of oil spills and utilize the most appropriate countermeasures available. In this paper, the authors report on work to elucidate the role that physicochemical factors play in determining an oil's tendency to emulsify. The authors studied the emulsification behavior of oils of known composition to examine the importance of oil chemistry in the emulsification process

Interaction of oil and mineral fines on shorelines: review and assessment

International Nuclear Information System (INIS)

Owens, Edward H.; Lee, Kenneth

2003-01-01

The interaction of fine mineral particles with stranded oil in an aqueous medium reduces the adhesion of the oil to solid surfaces, such as sediments or bedrock. The net result is the formation of stable, micron-sized, oil droplets that disperse into the water column. In turn, the increase in surface area makes the oil more available for biodegradation. This interaction, referred to as oil-mineral aggregate (OMA) formation, can explain how oiled shorelines are cleaned naturally in the absence of wave action in very sheltered coastal environments. OMA formation also plays an important role in the efficacy of shoreline treatment techniques, such as physical mixing and sediment relocation that move oiled sediments into the zone of wave action to promote the interaction between oil and mineral fines. Successful application of these shoreline treatment options has been demonstrated at two spill events (the Tampa Bay response in Florida and the Sea Empress operation in Wales) and at a controlled oil spill experiment in the field (the 1997 Svalbard ITOSS program). Sediment relocation harnesses the hydraulic action of waves so that the processes of fine-particle interaction and physical abrasion usually occur in tandem on open coasts. There has been no evidence of significant detrimental side-effects of residual oil in pelagic or benthic environments associated with the use of these treatment options to enhance rates of dispersion and oil biodegradation

Interaction of oil and mineral fines on shorelines: review and assessment

Energy Technology Data Exchange (ETDEWEB)

Owens, Edward H.; Lee, Kenneth

2003-12-01

The interaction of fine mineral particles with stranded oil in an aqueous medium reduces the adhesion of the oil to solid surfaces, such as sediments or bedrock. The net result is the formation of stable, micron-sized, oil droplets that disperse into the water column. In turn, the increase in surface area makes the oil more available for biodegradation. This interaction, referred to as oil-mineral aggregate (OMA) formation, can explain how oiled shorelines are cleaned naturally in the absence of wave action in very sheltered coastal environments. OMA formation also plays an important role in the efficacy of shoreline treatment techniques, such as physical mixing and sediment relocation that move oiled sediments into the zone of wave action to promote the interaction between oil and mineral fines. Successful application of these shoreline treatment options has been demonstrated at two spill events (the Tampa Bay response in Florida and the Sea Empress operation in Wales) and at a controlled oil spill experiment in the field (the 1997 Svalbard ITOSS program). Sediment relocation harnesses the hydraulic action of waves so that the processes of fine-particle interaction and physical abrasion usually occur in tandem on open coasts. There has been no evidence of significant detrimental side-effects of residual oil in pelagic or benthic environments associated with the use of these treatment options to enhance rates of dispersion and oil biodegradation.

Centrifugal Pump Effect on Average Particle Diameter of Oil-Water Emulsion

Science.gov (United States)

Morozova, A.; Eskin, A.

2017-11-01

In this paper we review the process of oil-water emulsion particles fragmentation in a turbulent flow created by a centrifugal pump. We examined the influence of time necessary for oil-water emulsion preparation on the particle size of oil products and the dependence of a centrifugal pump emulsifying capacity on the initial emulsion dispersion. The investigated emulsion contained the brand fuel oil M-100 and tap water; it was sprayed with a nozzle in a gas-water flare. After preparation of the emulsion, the centrifugal pump was turned on and the emulsion samples were taken before and after the pump passing in 15, 30 and 45 minutes of spraying. To determine the effect the centrifugal pump has on the dispersion of the oil-water emulsion, the mean particle diameter of the emulsion particles was determined by the optical and microscopic method before and after the pump passing. A dispersion analysis of the particles contained in the emulsion was carried out by a laser diffraction analyzer. By analyzing the pictures of the emulsion samples, it was determined that after the centrifugal pump operation a particle size of oil products decreases. This result is also confirmed by the distribution of the obtained analyzer where the content of fine particles with a diameter less than 10 μm increased from 12% to 23%. In case of increasing emulsion preparation time, a particle size of petroleum products also decreases.

Chemical and phase composition of powders obtained by electroerosion dispersion from alloys WC-Co

International Nuclear Information System (INIS)

Putintseva, M.N.

2004-01-01

A consideration is given to the dependence of chemical and phase compositions of dispersed powders on the conditions, the medium of electroerosion dispersing and the content of cobalt in an initial alloy. It is shown that dissociation of carbon from tungsten carbide proceeds even on dispersing in liquid hydrocarbon-containing media (kerosene and machine oil). The phase composition is determined to a large extent by a medium of dispersing and a cobalt content in the initial alloy. In all powders complex tungsten-cobalt carbides and even Co 7 W 6 intermetallic compounds are found [ru

Chemical and Phase Composition of Powders Obtained by Electroerosion Dispersion from WC - Co Alloys

Science.gov (United States)

Putintseva, M. N.

2004-03-01

The dependence of the chemical and phase composition of dispersed powders on the mode and medium of electroerosion dispersion and the content of cobalt in the initial alloy is considered. It is shown that the dissociation of carbon from tungsten carbide occurs even in dispersion in liquid hydrocarbon-bearing media (kerosene and industrial oils). The phase composition is primarily determined by the dispersion medium and the content of cobalt in the initial alloy. Compound tungsten-cobalt carbides and even a Co7W6 intermetallic are determined in all the powders.

Oil spill dispersants induce formation of marine snow by phytoplankton-associated bacteria

NARCIS (Netherlands)

Eenennaam, van J.S.; Wei, Yuzhu; Grolle, K.C.F.; Foekema, E.M.; Murk, A.J.

2016-01-01

Unusually large amounts of marine snow, including Extracellular Polymeric Substances (EPS), were formed during the 2010 Deepwater Horizon oil spill. The marine snow settled with oil and clay minerals as an oily sludge layer on the deep sea floor. This study tested the hypothesis that the

Dispersive microextraction based on water-coated Fe₃O₄ followed by gas chromatography-mass spectrometry for determination of 3-monochloropropane-1,2-diol in edible oils.

Science.gov (United States)

Zhao, Qin; Wei, Fang; Xiao, Neng; Yu, Qiong-Wei; Yuan, Bi-Feng; Feng, Yu-Qi

2012-06-01

In the present work, we developed a novel dispersive microextraction technique by combining the advantages of liquid-phase microextraction (LPME) and magnetic solid-phase extraction (MSPE). In this method, trace amount of water directly absorbed on bare Fe₃O₄ to form water-coated Fe₃O₄ (W-Fe₃O₄) and rapid extraction can be achieved while W-Fe₃O₄ dispersed in the sample solution. The analyte adsorbed W-Fe₃O₄ can be easily collected and isolated from sample solution by application of a magnet. It was worth noting that in the proposed method water was used as extractant and Fe₃O₄ served as the supporter and retriever of water. The performance of the method was evaluated by extraction of 3-monochloropropane-1,2-diol (3-MCPD) from edible oils. The extracted 3-MCPD was then derived by a silylanization reagent (1-trimethylsilylimidazole) before gas chromatography-mass spectrometry (GC-MS) analysis. Several parameters that affected the extraction and derivatization efficiency were investigated. Our results showed that the limit of detection for 3-MCPD was 1.1 ng/g. The recoveries in spiked oil samples were in the range of 70.0-104.9% with the RSDs less than 5.6% (intra-day) and 6.4% (inter-day). Taken together, the simple, rapid and cost-effective method developed in current study, offers a potential application for the extraction and preconcentration of hydrophilic analytes from complex fatty samples. Copyright © 2012 Elsevier B.V. All rights reserved.

Analysis of the Komineft Pipeline oil

Energy Technology Data Exchange (ETDEWEB)

Lambert, P.; Wang, Z.; Fieldhouse, B.; Jokuty, P.; Bissonnette, M.; Fingas, M. [Whiticar Scientific, Ottawa, ON (Canada); Whiticar, S. [Whiticar Scientific, Ottawa, ON (Canada); Kyle, D.; Landriault, M.; Sigouin, L.; Goldthorp, M.

1995-12-31

A detailed summary of the results of a study by Canadian experts acting as members of a United Nations (UN) team at a pipeline oil spill site in Western Siberia was presented. The purpose of the UN visit was to assess existing damage to the environment and to determine potential future hazards. A Komineft Pipeline oil sample was examined and its composition and characteristics were established. The oil characterization included determination of density, viscosity, pour point, interfacial tension, flash point, water content, dispersant effectiveness, sulphur content, evaporative loss, emulsion viscosity, emulsion water content and hydrocarbon group composition. 11 refs., 20 tabs., 17 figs.

Comparative risk assessment of spill response options for a deepwater oil well blowout: Part III. Stakeholder engagement.

Science.gov (United States)

Walker, Ann Hayward; Scholz, Debra; McPeek, Melinda; French-McCay, Deborah; Rowe, Jill; Bock, Michael; Robinson, Hilary; Wenning, Richard

2018-05-25

This paper describes oil spill stakeholder engagement in a recent comparative risk assessment (CRA) project that examined the tradeoffs associated with a hypothetical offshore well blowout in the Gulf of Mexico, with a specific focus on subsea dispersant injection (SSDI) at the wellhead. SSDI is a new technology deployed during the Deepwater Horizon (DWH) oil spill response. Oil spill stakeholders include decision makers, who will consider whether to integrate SSDI into future tradeoff decisions. This CRA considered the tradeoffs associated with three sets of response strategies: (1) no intervention; (2) mechanical recovery, in-situ burning, and surface dispersants; and, (3) SSDI in addition to responses in (2). For context, the paper begins with a historical review of U.S. policy and engagement with oil spill stakeholders regarding dispersants. Stakeholder activities throughout the project involved decision-maker representatives and their advisors to inform the approach and consider CRA utility in future oil spill preparedness. Copyright © 2018 Elsevier Ltd. All rights reserved.

Clay-oil flocculation and its role in natural cleansing in Prince William Sound following the Exxon Valdez oil spill

International Nuclear Information System (INIS)

Bragg, J.R.; Yang, S.H.

1995-01-01

Natural interactions of fine mineral particles with residue oil and seawater, in a process called clay-oil flocculation, were found to create solids-stabilized oil-in-water emulsions on shoreline sediments at numerous locations in Prince William Sound following the Exxon Valdez spill. In laboratory tests using oiled sediment samples from Prince William Sound, these emulsions were shown to facilitate natural cleansing and dispersion of oil from sediments by moving water. To investigate the effect of flocculation on natural cleansing, studies were conducted to determine the hydrodynamic energy needed for seawater to remove flocculated oil residues from sediments sampled from shorelines. Water was pumped at different velocities through a column packed with oiled sediment, and the amount and composition of oil removed from the sediment were measured as functions of water velocity and sediment movement. In separate tests, oil removal was observed in a wave tank that generated wave heights less than and greater than needed to move sediments. 28 refs., 13 figs., 7 tabs

Titanium oxide nanoparticles as additives in engine oil

Directory of Open Access Journals (Sweden)

Meena Laad

2018-04-01

Full Text Available This research study investigates the tribological behaviour of titanium oxide (TiO2 nanoparticles as additives in mineral based multi-grade engine oil. All tests were performed under variable load and varying concentrations of nanoparticles in lubricating oil. The friction and wear experiments were performed using pin-on-disc tribotester. This study shows that mixing of TiO2 nanoparticles in engine oil significantly reduces the friction and wear rate and hence improves the lubricating properties of engine oil. The dispersion analysis of TiO2 nanoparticles in lubricating oil using UV spectrometer confirms that TiO2 nanoparticles possess good stability and solubility in the lubricant and improve the lubricating properties of the engine oil. Keywords: Titanium oxide, Nanoparticles, UV spectrometer, Tribotester, Engine oil

New techniques on oil spill modelling applied in the Eastern Mediterranean sea

Science.gov (United States)

Zodiatis, George; Kokinou, Eleni; Alves, Tiago; Lardner, Robin

2016-04-01

Small or large oil spills resulting from accidents on oil and gas platforms or due to the maritime traffic comprise a major environmental threat for all marine and coastal systems, and they are responsible for huge economic losses concerning the human infrastructures and the tourism. This work aims at presenting the integration of oil-spill model, bathymetric, meteorological, oceanographic, geomorphological and geological data to assess the impact of oil spills in maritime regions such as bays, as well as in the open sea, carried out in the Eastern Mediterranean Sea within the frame of NEREIDs, MEDESS-4MS and RAOP-Med EU projects. The MEDSLIK oil spill predictions are successfully combined with bathymetric analyses, the shoreline susceptibility and hazard mapping to predict the oil slick trajectories and the extend of the coastal areas affected. Based on MEDSLIK results, oil spill spreading and dispersion scenarios are produced both for non-mitigated and mitigated oil spills. MEDSLIK model considers three response combating methods of floating oil spills: a) mechanical recovery using skimmers or similar mechanisms; b) destruction by fire, c) use of dispersants or other bio-chemical means and deployment of booms. Shoreline susceptibility map can be compiled for the study areas based on the Environmental Susceptibility Index. The ESI classification considers a range of values between 1 and 9, with level 1 (ESI 1) representing areas of low susceptibility, impermeable to oil spilt during accidents, such as linear shorelines with rocky cliffs. In contrast, ESI 9 shores are highly vulnerable, and often coincide with natural reserves and special protected areas. Additionally, hazard maps of the maritime and coastal areas, possibly exposed to the danger on an oil spill, evaluate and categorize the hazard in levels from low to very high. This is important because a) Prior to an oil spill accident, hazard and shoreline susceptibility maps are made available to design

Detection of DNA damage in mussels and sea urchins exposed to crude oil using comet assay

International Nuclear Information System (INIS)

Taban, I.C.; Bechmann, R.K.; Torgrimsen, S.; Baussant, T.; Sanni, S.

2004-01-01

The single-cell microgel electrophoresis assay or the comet assay was used to evaluate DNA damage of dispersed crude oil on sea urchins (Strongylocentrotus droebachiensis) and mussels (Mytilus edulis L.). Sea urchins were exposed to 0.06 and 0.25 mg/L dispersed crude oil in a continuous flow system, while the mussels were exposed to 0.015, 0.06 and 0.25 mg/L dispersed crude oil. Sea urchin coelomocytes and mussel haemocytes were sampled after 4 and 5 weeks exposure, respectively. In the sea urchin coelomocytes, there was a significant concentration-related increase in the percentage of DNA in comet tail. In mussel haemocytes, there was a significantly higher percentage of DNA in comet tail for all treatments compared to the control. The responses were concentration-related up to 0.06 mg/L oil. The two highest exposure concentrations of mussels were not significantly different from each other. These results indicate that the comet assay can be used for biomonitoring of DNA damage in marine invertebrates following oil contamination. (author)

A new approach to model strain change of gelled waxy crude oil under constant stress

DEFF Research Database (Denmark)

Hou, Lei; Song, Changyu; Yan, Wei

2014-01-01

Deformation of gelled waxy crude oil with loaded stress is worthy of research for the flow assurance of pipelining system. A dispersion parameter was introduced to characterize the disruption degree of wax crystal structure in crude oil with shear action. Based on fractional calculus theory, a rh...... monotonously with test temperature. Multiple creep curves of gelled waxy crude oil at a certain temperature can be described with this model......., a rheological model incorporating dispersion parameter was proposed to describe creep of gelled waxy crude. A discrete and numerical algorithm was proposed to solve the model. Combining with the experimental results of five kinds of waxy crude oil, the model parameters were regressed and found to change...

Ultrasonic splitting of oil-in-water emulsions

DEFF Research Database (Denmark)

Hald, Jens; König, Ralf; Benes, Ewald

1999-01-01

Standing resonant ultrasonic wave fields can be utilized for liquid–liquid separation of the dispersed particles and the fluid caused by the acoustic radiation pressure and the induced particle agglomeration or coagulation/coalescence process. For the splitting of oil-in-water emulsions, the avai......Standing resonant ultrasonic wave fields can be utilized for liquid–liquid separation of the dispersed particles and the fluid caused by the acoustic radiation pressure and the induced particle agglomeration or coagulation/coalescence process. For the splitting of oil-in-water emulsions......, the available piezoelectric composite transducer technology was improved and a dedicated resonator with crossed plane wave sonication geometry has been developed. The resonator chamber is entirely made of aluminium or tempax glass and the PZT piezoceramic transducer delivers an acoustic energy flow density...... of up to 24 W/cm2 into the sonication volume. The chosen resonance frequency is kept stable by automatic frequency control utilizing the maximum true power criterion. Physically and chemically well-defined low and high density pure laboratory and also industrially used cooling-lubricating oil...

Hydrodeoxygenation of oils from cellulose in single and two-stage hydropyrolysis

Energy Technology Data Exchange (ETDEWEB)

Rocha, J.D.; Snape, C.E. [Strathclyde Univ., Glasgow (United Kingdom); Luengo, C.A. [Universidade Estadual de Campinas, SP (Brazil). Dept. de Fisica Aplicada

1996-09-01

To investigate the removal of oxygen (hydrodeoxygenation) during the hydropyrolysis of cellulose, single and two-stage experiments on pure cellulose have been carried out using hydrogen pressures up to 10 MPa and temperatures over the range 300-520{sup o}C. Carbon, oxygen and aromaticity balances have been determined from the product yields and compositions. For the two-stage tests, the primary oils were passed through a bed of commercial Ni/Mo {gamma}-alumina-supported catalyst (Criterion 424, presulphided) at 400{sup o}C. Raising the hydrogen pressure from atmospheric to 10 MPa increased the carbon conversion by 10 mole % which was roughly equally divided between the oil and hydrocarbon gases. The oxygen content of the primary oil was reduced by over 10% to below 20% w/w. The addition of a dispersed iron sulphide catalyst further increased the oil yield at 10 MPa and reduces the oxygen content of the oil by a further 10%. The effect of hydrogen pressure on oil yields was most pronounced at low flow rates where it is beneficial in helping to overcome diffusional resistances. Unlike the dispersed iron sulphide in the first stage, the use of the Ni-Mo catalyst in the second stage reduced both the oxygen content and aromaticity of the oils. (Author)

Effect of temperature and dispersant (COREXIT® EC 9500A) on aerobic biodegradation of benzene in a coastal salt marsh sediment.

Science.gov (United States)

Tao, Rui; Olivera-Irazabal, Miluska; Yu, Kewei

2018-08-01

The coastal ecosystem in the northern Gulf of Mexico (GoM) has been seriously impacted by the 2010 BP oil spill. Two experiments were conducted to study the effect of temperature and addition of the dispersant on biodegradation of benzene, as a representative of petroleum hydrocarbon, in a coastal salt marsh sediment under aerobic conditions. The results show that benzene biodegradation was approximately 6 time faster under aerobic conditions (Eh > +300 mV) than under anaerobic iron-reduction conditions (+14 mV  10 °C > 30 °C as expected in a saline environment. Application of the dispersant caused initial fluctuations of benzene vapor pressure during the incubation due to its hydrophobic and hydrophilic nature of the molecules. Presence of the dispersant shows an inhibitory effect on benzene biodegradation, and the inhibition increased with concentration of the dispersant. The Gulf coast sediment seems in a favorable scenario to recover from the BP oil spill with an average temperature around 20 °C in spring and fall season. Application of the dispersant may be necessary for the oil spill rescue operation, but its side effects may deserve further investigations. Copyright © 2018 Elsevier Ltd. All rights reserved.

The effect of coconut oil and palm oil as substituted oils to cocoa butter on chocolate bar texture and melting point

Science.gov (United States)

Limbardo, Rebecca Putri; Santoso, Herry; Witono, Judy Retti

2017-05-01

Cocoa butter has responsibility for dispersion medium to create a stable chocolate bar. Due to the economic reason, cocoa butter is partially or wholly substituted by edible oils e.g palm oil and coconut oil. The objective of the research was to observe the effect of oil substitution in the chocolate bar towards its melting point and texture. The research were divided in three steps which were preliminary research started with fat content analysis in cocoa powder, melting point analysis of substituted oils anc cocoa butter, and iodine number analysis in vegetable fats (cocoa butter, coconut oil, and palm oil), chocolate bar production with substitution 0%, 20%, 40%, 60%, 80%, and 100%wt of cocoa butter with each of substituted oils, and analysis process to determine the chocolate bar melting point with DSC and chocolate bar hardness with texture analyser. The increasement of substituted oils during substitution in chocolate bar would reduce the melting point of chocolate bar from 33.5°C to 31.6°C in palm oil substitution with cocoa butter and 33.5°C to 30.75°C in coconut oil substitution. The hardness of chocolate with palm oil were around 88.5 to 139 g on the 1st cycle and 22.75 to 132 g on the 2nd cycle. The hardness of chocolate with coconut oil were around 74.75 to 152.5 g on the 1st cycle and 53.25 to 132 g on the 2nd cycle. Maximum amount of fats substitution to produce a stable texture chocolate bar is 60% wt.

Dataset on experimental investigation of gum arabic coated alumina nanoparticles for enhanced recovery of nigerian medium crude oil.

Science.gov (United States)

Orodu, Oyinkepreye D; Orodu, Kale B; Afolabi, Richard O; Dafe, Eboh A

2018-08-01

The dataset in this article are related to an experimental Enhanced Oil Recovery (EOR) scheme involving the use of dispersions containing Gum Arabic coated Alumina Nanoparticles (GCNPs) for Nigerian medium crude oil. The result contained in the dataset showed a 7.18% (5 wt% GCNPs), 7.81% (5 wt% GCNPs), and 5.61% (3 wt% GCNPs) improvement in the recovery oil beyond the water flooding stage for core samples A, B, and C respectively. Also, the improvement in recovery of the medium crude oil by the GCNPs dispersions when compared to Gum Arabic polymer flooding was evident in the dataset.

In situ bioremediation strategies for oiled shoreline environments

International Nuclear Information System (INIS)

Lee, K.; Mora, S. de

1999-01-01

Despite advances in preventative measures, recent events have demonstrated that accidental oil spills at sea will still occur. While physical (e.g. booms and skimmers) and chemical (e.g. chemical dispersants) methods have been developed to recover and/or disperse oil spilled at sea, they are not 100% effective and are frequently limited by operational constraints attributed to sea state and/or nature of the contamination. As a result, oil spills frequently impact shoreline environments. In situ bioremediation, the addition of substances or modification of habitat at contaminated sites to accelerate natural biodegradation processes, is now recognised as an alternative spill response technology of the remediation of these sites. Recommended for use following the physical removal of bulk oil, this treatment strategy has an operational advantage in that it breaks down and/or removes the residual contamination in place. Laboratory experiments and field trials have demonstrated the feasibility and success of bioremediation strategies such as nutrient enrichment to enhance bacterial degradation of oil on cobble, sand beach and salt marsh environments. With improved knowledge of the factors that limit natural oil degradation rates, the feasibility of other strategies such as phytoremediation, enhanced oil-mineral fines interaction and the addition of oxygen or alternative electron acceptors are now being evaluated. Laboratory and field test protocols are being refined for the selection of effective bioremediation agents and methods of application. It is recommended that future operational guidelines include real time product efficacy test and environmental effects monitoring programs. Termination of treatment should be implemented when: 1) it is no longer effective; 2) the oil has degraded to acceptable biologically benign concentrations; or 3) toxicity due to the treatment is increasing. (Author)

Studies on the oil spillage near shorline

Science.gov (United States)

Voicu, I.; Dumitrescu, L. G.; Panaitescu, V. F.; Panaitescu, M.

2017-08-01

This paper presents a simulation of an oil spillage near shoreline in real conditions. The purpose of the paper is to determine the evolution of oil spill on sea water surface and in the same time to determine the total costs of depolluting operations organized by the authorities. The simulation is made on the PISCES II Simulator (Potential Incident Simulator Control and Evaluation System) which is designed to handle on real situations such as oil pollutions of the sea. The mathematical model used by the simulator is the dispersion oil-water model, taking account all external conditions such as air/sea water temperature, current/wind speed and direction, sea water density, petroleum physical properties. In the conclusions chapter is presented oil spill details with a financial report for total costs of depolluting operation.

Emulsion stability and properties of fish gelatin-based films as affected by palm oil and surfactants.

Science.gov (United States)

Nilsuwan, Krisana; Benjakul, Soottawat; Prodpran, Thummanoon

2016-05-01

Gelatin films exhibit the poor water vapour barrier properties. The use of palm oil, which is abundant and available in Thailand, can be a means to lower water vapour migration. To disperse oil in film-forming dispersion (FFD), a surfactant along with appropriate homogenization is required. The study aimed to investigate the influence of palm oil level and surfactants in the absence or presence of glycerol on characteristics of FFD and resulting gelatin films. Similar oil droplet sizes, both d32 and d43 values, of FFD containing soy lecithin were observed, regardless of palm oil level used (P > 0.05). FFD with Tween-20 had larger droplet size as the levels of oil increased (P palm oil level increased (P 0.05). FFD containing 500 or 750 g kg(-1) palm oil using soy lecithin as a surfactant in the presence of 300 g kg(-1) glycerol had the enhanced homogeneity and stability of oil droplets. The resulting gelatin film had the improved water vapour barrier properties. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Oil spills - effects and response

International Nuclear Information System (INIS)

Dicks, B.M.; White, I.C.

1992-01-01

The incidence of oil spills from offshore industry operates on the United Kingdom continental shelf is reported for the period 1979 to 1988. The properties of North Sea crude oils which determine their fate and effects when spilled onto the surface of the sea are summarized. Examples of oil impacts on specific North Sea habitats and communities are used to illustrate the effect of oil spills and the economic impact on human activities such as recreation, industry and fishing are considered. Since most oil spills will dissipate through natural processes if they remain at sea long enough, the most appropriate response to a spill from a platform in the middle of the sea is often aerial surveillance to monitor the movement and dissipation of the oil. However, if an active response is required, containment and collection of the oil or chemical dispersion are the two main options. In coastal waters, it will be necessary to focus protection efforts on selected sensitive areas of coastline. Once the oil is ashore there are still occasions when the best course of actions is to do nothing as clean-up operations may do more harm than good. If oil removal is feasible and necessary, the methods which are most effective are usually straightforward and require no sophisticated technology. Contingency planning is an essential preparation for all operations to deal with oil spills. (UK)

Dispersive effects on multicomponent transport through porous media

Science.gov (United States)

Dutta, Sourav; Daripa, Prabir

2017-11-01

We use a hybrid numerical method to solve a global pressure based porous media flow model of chemical enhanced oil recovery. This is an extension of our recent work. The numerical method is based on the use of a discontinuous finite element method and the modified method of characteristics. The impact of molecular diffusion and mechanical dispersion on the evolution of scalar concentration distributions are studied through numerical simulations of various flooding schemes. The relative importance of the advective, capillary diffusive and dispersive fluxes are compared over different flow regimes defined in the parameter space of Capillary number, Peclet number, longitudinal and transverse dispersion coefficients. Such studies are relevant for the design of effective injection policies and determining optimal combinations of chemical components for improving recovery. This work has been possible due to financial support from the U.S. National Science Foundation Grant DMS-1522782.

Nanoparticle enhanced evaporation of liquids: A case study of silicone oil and water

OpenAIRE

Zhang, Wenbin; Shen, Rong; Lu, Kunquan; Ji, Ailing; Cao, Zexian

2012-01-01

Evaporation is a fundamental physical phenomenon, of which many challenging questions remain unanswered. Enhanced evaporation of liquids in some occasions is of enormous practical significance. Here we report the enhanced evaporation of the nearly permanently stable silicone oil by dispersing with nanopariticles including CaTiO3, anatase and rutile TiO2. An evaporation rate as high as 1.33 mg/h·cm2 was measured in silicone oil when dispersed with 100 nm-sized CaTiO3 particles. Dependence of e...

Treatment of oil spill fire hazards with chemical dispersants: a case history

Energy Technology Data Exchange (ETDEWEB)

Kaufmann, S.

1982-10-01

Federal contingency plans include the use of chemical dispersants to ameliorate hazardous situations caused by spills of flammable or explosive petroleum products. The closing of the Williamsburg Bridge in New York City, when a gasoline tanker exploded and sank under it, was nearly overshadowed by the leakage of 7 750 000 L (2 000 000 gal) of gasoline from a storage facility in Boston. The threat to a densely populated neighborhood of six-family tenement houses and a large racetrack that stabled hundreds of Thoroughbred horses led to the use of a chemical dispersant to neutralize the fire hazard. Favorable results by fire departments in recent years, as a result of training, have established dispersants as the method of choice to handle nonburning spill incidents. Even though the teams that responded to several such emergencies of course held the protection of life and property as paramount, no toxicological environmental effects were noted during subsequent observations.

Stability, rheology and thermal analysis of functionalized alumina- thermal oil-based nanofluids for advanced cooling systems

International Nuclear Information System (INIS)

Ilyas, Suhaib Umer; Pendyala, Rajashekhar; Narahari, Marneni; Susin, Lim

2017-01-01

Highlights: • Alumina nanoparticles are functionalized with oleic acid. • Functionalization of alumina nanoparticles gives better dispersion in thermal oil. • Thermophysical properties of nanofluids are experimentally measured. • TGA confirms the improvement in life of nanofluids. - Abstract: Thermal oils are widely used as cooling media in heat transfer processes. However, their potential has not been utilised exquisitely in many applications due to low thermal properties. Thermal oil-based nanofluids are prepared by dispersing functionalized alumina with varying concentrations of 0.5–3 wt.% to enhance thermal properties of oil for advanced cooling systems. The oleic acid coated alumina is prepared and then dispersed in the oil to overcome the aggregation of nanoparticles in base fluid. The surface characterizations of functionalized nanoparticles are performed using different analysis such as XRD, EDS, SEM, TEM and FTIR. Dispersion behaviour and agglomeration studies are conducted at natural and functionalized conditions using different analysis to ensure long-term stability of nanofluids. In addition, rheological behaviour of non-Newtonian nanofluids is studied at high shear rates (100–2000 s"−"1). Effective densities and enhancement in thermal conductivities are measured for different nanofluids concentrations. Specific heat capacity is measured using Differential Scanning Calorimetry. The correlations are developed for thermophysical properties of nanofluids. Thermogravimetric analysis is performed with respect to temperature and time to exploit the effect of the addition of nanoparticles on the degradation of nanofluids. Significant improvement in the thermal properties of oil is observed using highly stable functionalized alumina nano-additives.

Assessment of treated vs untreated oil spills. Final report

Energy Technology Data Exchange (ETDEWEB)

Wilson, M.P.

1981-02-01

The results of a series of studies conducted to determine the practicability and feasibility of using dispersants to mitigate the impact of an oil spill on the environment are described. The method of approach is holistic in that it combines the physical, chemical, microbial and macro-fauna response to a spill treated with dispersants and compares this with spills that are left untreated. The program integrates mathematical, laboratory, meso-scale (three 20 foot high by three feet in diameter tanks, in-situ experiments and analyses to determine if the use of dispersants is an effective oil spill control agent. In summary, it appears viable to use dispersants as determined on a case by case basis. The case for using dispersants has to be based on whether or not their use will mitigate the environmental impact of the spill. In the case of an open ocean spill that is being driven into a rich inter-tidal community, the use of dispersants could greatly reduce the environmental impact. Even in the highly productive George's Bank area at the height of the cod spawning season, the impact of the use of dispersants is well within the limits of natural variability when the threshold toxicity level is assumed to be as low as 100 ppB, a level which is often found in the open ocean. Thus, it appears that dispersants can and should be used when it is evident that their use will mitigate the impacts of the spill. Their use in areas where there is poor circulation and therefore little possibility of rapid dilution is more questionable and should be a subject of future studies.

Experimental Study on Characteristics of Oil Particle Distribution in Water-Gelled Crude Oil Two-Phase Flow System

Directory of Open Access Journals (Sweden)

Liu Xiaoyan

2014-06-01

Full Text Available The conventional gathering and transportation mode of heating the produced fluid of oil wells with hot water or steam may result in excessive energy consumption. In order to perform the unheated transportation, the idea of hydraulic suspension transport of the gelled crude oil is proposed based on the actual production of Daqing Oilfield, and the experimental system is established to test characteristics of oil particle distribution which have an important effect on the hydraulic suspension transportation. In the experiment, the image of gelled crude oil particle distribution was obtained in a horizontal pipe with inner diameter of 0.053 m, and then the law of particle distribution was investigated by the theoretical model. The results showed that the gelled crude oil hydraulic suspension transport could be achieved without any chemical reagent when the gelled crude oil was transformed into particles and dispersedly suspended in water. The results also showed that the gelled oil particles of 0–4 mm in size accounted for 92% or more of all particles, and the percentage of gelled crude oil particles of a size of 4 mm gradually increased with the increasing mixed flow rate.

Compound Method to Disperse CaCO3 Nanoparticles to Nano-Size in Water.

Science.gov (United States)

Gu, Sui; Cai, Jihua; Wang, Jijun; Yuan, Ye; Chang, Dewu; Chikhotkin, Viktor F

2015-12-01

The invalidation of CaCO3 nanoparticles (nCaCO3) is often caused by the fact of agglomeration and inhomogeneous dispersion which limits its application into water-based drilling muds for low permeability reservoirs such as coalbed methane reservoir and shale gas/oil reservoir. Effective methods to disperse nCaCO3 to nano-size (≤ 100 nm) in water have seldom been reported. Here we developed a compound method containing mechanical stirring, ultrasonic treatment, the use of surfactant and stabilizer to disperse nCaCO3 in water. It comprises the steps adding 2% nCaCO3, 1% sodium dodecyl sulfonate (SDS), 2% cetyltrimethyl ammonium bromide (CTAB), 2% OP-10, 3% to 4% biopolymer (XC) in water successively, stirring it at a shear rate of 6000 to 8000 r/min for 15 minutes and treating it with ultrasonic at a frequency of 28 KHz for 30 to 40 minutes. The dispersed nCaCO3 was characterized with scanning electron microscope (SEM), transmission electron microscope (TEM) and particle size distribution (PSD) tests. We found that nCaCO3 could be dispersed to below 100 nm in water and the medium value of nCaCO3 was below 50 nm. This method paved the way for the utilization of nCaCO3 in drilling fluid and completion fluid for low permeability reservoirs such as coal seams and shale gas/oil formations.

Tribological characteristics of monodispersed cerium borate nanospheres in biodegradable rapeseed oil lubricant

Energy Technology Data Exchange (ETDEWEB)

Boshui, Chen, E-mail: boshuichen@163.com; Kecheng, Gu; Jianhua, Fang; Jiang, Wu; Jiu, Wang; Nan, Zhang

2015-10-30

Graphical abstract: - Highlights: • Monodispersed stearic acid-capped cerium borate composite nanoparticles were prepared by hydrothermal method. Their morphologies, element compositions, size distributions, crystal and chemical structures, hydrophobic characteristics were also characterized. • The surface-capped cerium borate nanoparticles exhibited excellent dispersing stability in rapeseed oil. As new lubricating additives, they were also outstanding in enhancing friction-reducing and anti-wear capacities of rapeseed oil in biodegradable rapeseed oil. The results presented in this paper would be of important significance for developing green lubricants and lubricant additives. • The prominent tribological performances of SA/CeBO{sub 3} in rapeseed oil were investigated and attributed to the formation of a composite boundary lubrication film mainly composed of lubricous tribochemical species on the tribo-surfaces. - Abstract: Stearic acid-capped cerium borate composite nanoparticles, abbreviated as SA/CeBO{sub 3}, were prepared by hydrothermal method. The morphologies, element compositions, size distributions, crystal and chemical structures, hydrophobic characteristics, of SA/CeBO{sub 3} were characterized by scanning electron microscope, energy dispersive X-ray spectrometer, dynamic laser particle size analyzer, X-ray diffraction, and Fourier transform infrared spectrometer, respectively. The friction and wear performances of SA/CeBO{sub 3} as a lubricating additive in a rapeseed oil were evaluated on a four-ball tribo-tester. The tribochemical characteristics of the worn surfaces were investigated by X-ray photoelectron spectroscopy. The results showed that the hydrophobic SA/CeBO{sub 3} were monodispersed nanospheres with an average diameter of 8 nm, and exhibited excellent dispersing stability in rapeseed oil. Meanwhile, SA/CeBO{sub 3} nanospheres were outstanding in enhancing friction-reducing and anti-wear capacities of rapeseed oil. The prominent

OSIS: A Windows 3 Oil Spill Information System

International Nuclear Information System (INIS)

Leech, M.; Walker, M.; Wiltshire, M.; Tyler, A.

1993-01-01

An oil spill modelling and analysis system called the Oil Spill Information System (OSIS) has recently been developed. OSIS uses a model of oceanographic processes to predict three-dimensional spreading and transport of an oil slick under the influence of wind, waves, tide, turbulence, and shear diffusion. Oil weathering and fate processes of emulsification, evaporation, and dispersion are also simulated. The physical models have been tested against data obtained from sea trials and spill incidents. OSIS uses an object-oriented programming technique and presents model output as maps, graphs, and tables in multiple windows and can link to other Windows packages to create a suite of spill information management tools. 15 refs., 12 figs

Sequential enrichment of microbial population exhibiting enhanced biodegradation of crude oil

International Nuclear Information System (INIS)

Venkateswaran, Kasthuri; Harayama, Shigeaki.

1995-01-01

The distribution of oil-degrading bacteria in the coastal waters and sediments of Hokkaido, Japan, was surveyed. It was found that the potential of mixed microbial populations to degrade weathered crude oil was not confined to any ecological components (water or sediment) nor to the sampling stations. One microbial culture that was stable during repeated subculturing degraded 45% of the saturates and 20% of the aromatics present in crude oil in 10 days during the initial screening. The residual hydrocarbons in this culture were extracted by chloroform and dispersed in a fresh seawater-based medium and subsequently inoculated with microorganisms from the first culture. After full growth of the second culture, the residual hydrocarbons were extracted and dispersed in a fresh medium in which microorganisms from the second culture had been inoculated. This sequential process was carried out six times to enrich those microorganisms that grew on the recalcitrant components of crude oil. After repeated exposure of the residual crude oil to the enriched microorganisms, about 80% of the initially added crude oil was degraded. The cultures obtained after each enrichment cycle were kept, and the degradation of fresh crude oil by the enriched microorganisms was monitored. The degrading activity of the enriched cultures increased as the number of enrichment cycles increased. A microbial population that had been selected six times on the residual crude oil could degrade 70% of the saturates and 30% of the aromatics of crude oil, indicating that growth of a microbial population on residual crude oil improved its ability to biodegrade crude oil. 21 refs., 2 tabs., 7 figs

Film Thickness Estimation for the Oil Applied to the Inner Surface of Slim Tubes

Directory of Open Access Journals (Sweden)

Jozef Svetlík

2017-09-01

Full Text Available The article deals with the approximation of the results of experimental measurement of coating of the inner surface of slim pipes with special oil, using a dispersion oil fraction. The reason for such treatment of the inner surface of the tubes is the anti-corrosion protection or various other requirements. The oil manufacturer prescribes the minimum required layer to guarantee the anti-corrosion protection parameters. Therefore, it is advisable to know the most exact coating parameters for different pipe diameters. The measured results give us an assumption of how much oil is sufficient to coat the inside of a pipe. The main idea lies in the correct estimation of coefficients in the three-parameter exponential dependence. For the initial estimates, Nelder–Mead’s minimization method was used. The condition for meeting the lower estimate of the minimum thickness of the oil layer was determined. Following graphic processing of minimization of individual pipe diameters, in some cases, the coefficients were adjusted manually. The result is that the oil thickness depends on the distance of the investigated point from the beginning of the tube, or on the point of entry of the dispersion oil fraction.

Uncovering the exposure mechanisms of sunken heavy oil that makes it chronically toxic to early life stages of fish

International Nuclear Information System (INIS)

Martin, J.; Young, G.; Lemire, B.; Hodson, P.

2010-01-01

A train derailment in 2005 caused the release of 150,000 litres of No. 6 heavy fuel oil into a lake in Alberta. The oil is a residue of the crude oil refinement process and contains 3-4 ringed alkylated forms of polycyclic aromatic hydrocarbons (PAH) that are known to cause sub-lethal toxic responses during the early life stages of rainbow trout. Because the oil does not disperse well, oil patches still persist in near-shore sediments of the lake where fish spawn. This study assessed how the behaviour of heavy oil in water interacts with exposure and toxicity to the early life stages of fish. Daily renewal tests with heavy fuel oil coated on glass plate demonstrated higher levels of toxicity to trout embryos than oil that was mechanically or chemically dispersed. A flow-through oil gravel column was used to assess whether the toxic constituents of the heavy oil are transferred quickly enough to cause toxicity. The aim of the study was to develop exposure and toxicity test methods that accurately reflect the behaviour of heavy oil after a spill.

The use of chromatographic indexes to study the biodegradation of crude oil in cold/icy seawater

International Nuclear Information System (INIS)

Siron, R.; Pelletier, E.

1993-01-01

A group of five protected mesocosms (3.5 m 3 each) was used to study the biodegradation of dispersed crude oil in cold and icy seawater. A wide range of oil concentrations was tested over four experiments lasting two weeks to six months. Various oil treatments were studied with respect to the natural bacterial degradation: chemically dispersed and untreated crude oil; and oil adsorbed on, and released from, an immersed substrate. The study was concerned with oil accommodated in the water column, accumulated in surface (sheens and emulsions), and collected in sediment traps. The oil biodegradation was assessed by means of the following gas chromatographic indexes: C17/pristane; C18/phytane; n-alkanes/isoprenoids; pristane/phytane; naphthalene/phenanthrene; 2-methyl naphthalene/1-methyl naphthalene; and methylnaphthalenes/total substituted naphthalenes. A combined index of biodegradation defined from the most significant hydrocarbon ratios is proposed to evaluate the overall biodegradation of dissolved compounds and oil droplets, involving both aliphatic and aromatic hydrocarbons. Coupled with mesocosm facilities, this approach appears very convenient to determine the potential degradability of crude oils by natural indigenous microflora. 26 refs., 11 figs., 2 tabs

THE PHYSICAL AND CHEMICAL CHARACTERIZATION OF THE EMISSIONS FROM A RESIDENTIAL OIL BOILER

Science.gov (United States)

The toxicity of emissions from the combustion of home heating oil and the use of residential oil boilers (ROB) is an important health concern. Yet scant physical and chemical information about the emissions from this source are available for dispersion, climate, and source-recep...

Dispersion behaviour of rape oil methyl ester and rape-oil-based hydraulic oils in soils and on soil surfaces with due consideration to the technical performance capabilities of the hydraulic oils. Part-project 1: studies on model ecosystems. Part-project 2: provision of oils with defined degrees of ageing. Final report; Ausbreitungsverhalten von Rapsoelmethylester und Hydraulikoelen auf Rapsoelbasis im Boden und auf Bodenoberflaechen unter Beruecksichtigung der technischen Leistungsfaehigkeit der Hydraulikoele. Teilvorhaben 1: Untersuchungen an Modelloekosystemen. Teilvorhaben 2: Bereitstellung definiert gealterter Hydraulikoele. Abschlussbericht

Energy Technology Data Exchange (ETDEWEB)

Paul, W.; Schuett, C.; Roemer, A.; Foelster, N.; Lemke, M.

2001-07-01

The purpose of the present cooperative research project is to study the toxicity, the degradation and in particular the dispersion behaviour of biologically rapidly degradable hydraulic oils and rape oil methyl esters (RME) in soils and waters with a special focus on hydraulic oils. This is to serve as a basis for developing guidelines for action in the event of accidents involving biologically rapidly degradable hydraulic fluids that ensure proper accident reporting and handling. The outcome of the cooperative research project is to permit a first risk assessment for the soil and water compartments in the event of accidents involving hydraulic oils and RME. Another task is to clarify to what extent it is permissible to deviate from the usual measures prescribed for oil accidents involving crude oil when biologically rapidly degradable hydraulic oils or RME are involved instead. [German] Ziel des Verbundvorhabens ist es, die Toxizitaet, den Abbau und insbesondere das Ausbreitungsverhalten von biologisch schnell abbaubaren Hydraulikoelen und Rapsoelmethylester (RME) in Boden und Wasser zu untersuchen, wobei der Schwerpunkt der Arbeiten bei den Hydraulikoelen liegt. Damit sollen Verfahrensrichtlinien angegeben werden, die im Falle von Unfaellen mit biologisch schnell abbaubaren Hydraulikfluessigkeiten oder Biodiesel eine angemessene Unfallaufnahme und -abwicklung sicherstellen. Als Ergebnis des Verbundvorhabens soll eine erste Risikoabschaetzung fuer die Kompartimente Boden und Wasser bei Unfaellen mit Hydraulikoelen und RME moeglich sein. Darueber hinaus soll geklaert werden, inwieweit Abweichungen von den ueblichen Massnahmen bei Oelunfaellen mit Mineraloelprodukten im Vergleich zu biologisch schnell abbaubaren Hydraulikoelen oder RME moeglich sind. (orig.)

Oil spill analysis in Sao Sebastiao Channel. Sao Paulo (SP) Brazil, from 1974 to 1994

International Nuclear Information System (INIS)

Poffo, Iris R.F.; Midaglia, Carmen L.; Heitzmann, Sueli R.; Caetano, Nelson; Cantao, Renato F.; Pompeia, Sergio L.; Eysink, Geraldo G.; Nakasaki, Akira

1996-01-01

Environmental accident files from PETROBRAS and CETEBS were studied. A total of 210 oil spill accidents were registered in Sao Sebastiao region (1974-1994), the oil reached the sea in 191 cases. The analysis was carried out by: cause of the accident, kind and amount of oil spilled, displacement of the oil spot, affected areas, dispersive used, amount of the oil and contaminated sands removes, waste disposal, and the relation between the wind direction intensity and the displacement of oil spot

Effective adsorption of oil droplets from oil-in-water emulsion using metal ions encapsulated biopolymers: Role of metal ions and their mechanism in oil removal.

Science.gov (United States)

Elanchezhiyan, S Sd; Prabhu, Subbaiah Muthu; Meenakshi, Sankaran

2018-06-01

Herein, synthesized and compared the three different kinds of hybrid bio-polymeric composites viz., lanthanum embedded chitosan/gelatin (La@CS-GEL), zirconium embedded chitosan/gelatin (Zr@CS-GEL) and cerium embedded chitosan/gelatin (Ce@CS-GEL) in terms of their oil uptake efficiency. The adsorption efficiency was studied under various optimized parameters like contact time, pH, dose, initial oil concentration and temperature. The oil adsorption capacity was found to be 91, 82 and 45% for La@CS-GEL, Zr@CS-GEL and Ce@CS-GEL composites respectively. The metals were used as a bridging material to connect both CS and GEL using the hydrophilic groups to enhance the oil recovery by hydrophobic interaction. Also, the introduction of metal ions on the surface of biopolymers would modify the oil/water properties which in turn, decrease the interfacial tension between oil and water phases. The mechanism of oil uptake was explained using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscope (SEM), energy dispersive X-ray (EDAX) and heat of combustion. The experimental data confirmed Langmuir isotherm as the best fit for oil adsorption process. Thermodynamic parameters such as standard free energy (ΔG°), standard enthalpy (ΔH°) and standard entropy (ΔS°) indicated that the oil adsorption was spontaneous and endothermic. The oil adsorption mechanism was established based on isotherm and thermodynamic models. Copyright © 2018 Elsevier B.V. All rights reserved.

Formulation of a Commercial Biosurfactant for Application as a Dispersant of Petroleum and By-products Spilled in Oceans

Directory of Open Access Journals (Sweden)

Bruno Galdino Freitas

2016-10-01

Full Text Available Oil spills in oceans cause irreparable damage to marine life and harm the coastal populations of affected areas. It is therefore fundamental to develop treatment strategies for such spills. Currently, chemical dispersants have been used during oil spills, although these agents have been increasingly restricted due to their toxic potential. Thus, the aim of the present study was to formulate a biodegradable commercial biosurfactant for application as a dispersant. Biosurfactants are scientifically known biomolecules produced by microorganisms capable of allowing water-oil interaction. Thus, a biosurfactant was produced by the yeast Candida bombicola URM 3718 cultivated in industrial waste and formulated with the addition of a potassium sorbate preservative for fractionated sterilisation (tyndallisation and the combination of fluent vaporisation with the preservative. After formulation, samples were stored for 120 days, followed by surface tension, emulsification and oil dispersant tests in sea water. The results were promising for the biosurfactant formulated with the preservative, which demonstrated stability and an absence of toxicity in experiments with a marine indicator. The commercial biosurfactant was tested at different pH values, temperatures and in the presence of salt, demonstrating potential industrial application at a cost compatible with the environmental field. The formulation process developed in this research was patented in the Brazilian National Intellectual Property Institute (patent number BR1020140179631.

The interaction of fine particles with stranded oil

International Nuclear Information System (INIS)

Owens, E.H.

1999-01-01

The interaction of micron-sized mineral particles with stranded oil reduces its adhesion to solid surfaces, such as sediments or bedrock. The net result is the formation of stable, micron-sized, oil droplets that disperse into the water column. In turn, the increase in surface area makes the oil more available for biodegradation. Oil and Fine-particle Interaction ('OFI') can explain how oiled shorelines are cleaned naturally in the absence of wave action in very sheltered coastal environments. Fine-particle interaction can be accelerated during a spill response by relocating the oiled sediments into the surf zone. This has been achieved successfully on two occasions to date: the Tampa Bay response in Florida, and the Sea Empress operation in Wales. Sediment relocation also causes physical abrasion by the hydraulic action of waves so that the processes of fine-particle interaction and surf washing usually occur in combination on open coasts. (author)

Investigation of Factors Influencing Dispersion of Liquid Hydrocarbons in Porous Media

Directory of Open Access Journals (Sweden)

Hussain Ali Baker

2016-08-01

Full Text Available An experimental work has been done to study the major factors that affect the axial dispersion of some hydrocarbons during liquid-liquid miscible displacement. Kerosene and gas oil are used as displacing phase while seven liquid hydrocarbons of high purity represent the displaced phase, three of the liquids are aromatics and the rest are of paraffinic base. In conducting the experiments, two packed beds of different porosity and permeability are used as porous media. The results showed that the displacement process is not a piston flow, breakthrough of displacing fluids are shown before one pore volume has been injected. The processes are stable with no evidence of viscous fingering. Dispersion model as adapted by Brigham et.al (1961 is used to determine the axial dispersion coefficient of displacing fluid. The results show an increasing in dispersion coefficient as the interstitial velocity and viscosity ratio increases.

Bioremediation of oil spills

International Nuclear Information System (INIS)

Foght, J.M.; Westlake, D.W.S.

1992-01-01

In-situ bioremediation of crude oil spills relies on either the indigenous microbes at the polluted site, whose degradative abilities are accelerated by adding such agents as fertilizers or dispersants, or on introducing pollutant-degrading microbes into the site (possibly accompanied by stimulatory chemicals). The bioremediation method to be used at a specific site must be selected to be suitable for that site and its environmental conditions. The basic components of bioremediation are outlined and the background information needed to understand the chemical and biological limitations of the technique are presented. Specifically, the microbial community, the crude oil substrate composition, and biological limiting factors are discussed. Generalized examples of bioremediation applications are illustrated. 10 refs

Hydrogenation upgrading of heavy oil residues

Energy Technology Data Exchange (ETDEWEB)

Krichko, A.A.; Maloletnev, A.S.; Mazneva, O.A.; Galkina, N.I. [Fossil Fuel Inst., Moscow (Russian Federation). Hydrogenation and Gasification Dept.; Suvorov, U.P.; Khadjiev, S.N. [Inst. Oil and Chemical Synthesis, Moscow (Russian Federation). Hydrogenation of Heavy Residues Dept.

1997-12-31

At present time in the world there is no simple and effective technology at low pressure (<15-20 MPa) which could give the opportunity to use oil residues for distillate fractions production. In Russia a process for hydrogenation (up 6 MPa hydrogen pressure) of high boiling point (b.p. >520 C) oil products, including high S, V and Ni contents ones, into distillates, feedstock for catalytic cracking (b.p. 360-520 C) and metal concentrates. The main point of the new process is as follows: the water solution of catalytic additive, for which purpose water soluble metal salts of VI-VIII groups are used, is mixed with heavy oil residues, dispersed and then subjected to additional supercavitation in a special apparatus. (orig.)

Effect of gelation of inner dispersed phase on stability of (w1/o/w2) multiple emulsions

NARCIS (Netherlands)

Oppermann, A.K.L.; Renssen, M.; Schuch, A.; Stieger, M.A.; Scholten, E.

2015-01-01

The use of water-in-oil-in-water (w1/o/w2) multiple emulsions offers a method for the reduction of oil in foods. In this study we investigated the influence of osmotic pressure tailoring and gelation of the inner dispersed w1 water droplets on the stability and yield of multiple emulsions. Yield is

Weathering of oils at sea: model/field data comparisons

International Nuclear Information System (INIS)

Daling, Per S.; Stroem, Tove

1999-01-01

The SINTEF Oil Weathering Model (OWM) has been extensively tested with results from full-scale field trials with experimental oil slicks in the Norwegian NOFO Sea trials in 1994 and 1995 and the AEA 1997 trials in UK. The comparisons between oil weathering values predicted by the model and ground-truth obtained from the field trials are presented and discussed. Good laboratory weathering data of the specific oil as input to the model is essential for obtaining reliable weathering predictions. Predications provided by the SINTEF-OWM enable oil spill personnel to estimate the most appropriate 'window of opportunity' for use of chemical dispersants under various spill situations. Pre-spill scenario analysis with the SINTEF Oil Spill Contingency and Response (OSCAR) model system, in which the SINTEF-OWM is one of several components, has become an important part of contingency plans as well as contingency training of oil spill personnel at refineries, oil terminals and offshore installations in Norway. (Author)

Characterization of water-in-oil emulsions produced with microporous hollow polypropylene fibers

Directory of Open Access Journals (Sweden)

HELMAR SCHUBERT

2000-11-01

Full Text Available The preparation of fine and monodispersed water-in-oil (W/O emulsions by utilizing hydrophobic hollow polypropylene fibers with 0.4 mm pores was investigated in this work. The experiments were carried out using demineralized water as the disperse phase, mineral oil Velocite No. 3 as the continuous phase, and polyglycerol polyricinoleate (PGPR 90 in the concentration range of 2.5 – 10 wt % as the oil-soluble emulsifier. The size of the water droplets in the prepared emulsions and the droplet size distribution strongly depend on the content of the disperse phase, the transmembrane pressure difference, and the emulsifier concentration. Stable emulsions with a very narrow droplet size distribution and a mean droplet diameter lower than 0.27 µm were produced using 10 wt % PGPR 90 at a pressure difference below 30 kPa.

Laser-fabricated castor oil-capped silver nanoparticles.

Science.gov (United States)

Zamiri, Reza; Zakaria, Azmi; Abbastabar, Hossein; Darroudi, Majid; Husin, Mohd Shahril; Mahdi, Mohd Adzir

2011-01-01

Silver nanoparticles were fabricated by ablation of a pure silver plate immersed in castor oil. A Nd:YAG-pulsed Q-switch laser with 1064-nm wavelength and 10-Hz frequency was used to ablate the plate for 10 minutes. The sample was characterized by ultraviolet-visible, atomic absorption, Fourier transform-infrared spectroscopies, and transmission electron microscopy. The results of the fabricated sample showed that the nanoparticles in castor oil were about 5-nm in diameter, well dispersed, and showed stability for a long period of time.

Controllable synthesis in a continuous mode of unsupported molybdenum catalysts with micro/nano size for heavy oil upgrading

Energy Technology Data Exchange (ETDEWEB)

Wang, J.; Hill, J.M.; Pereira Almao, P.R. [Calgary Univ., AB (Canada)

2004-07-01

Heavy oils contain significant amounts of impurities compared to conventional oils, thereby posing a challenge for hydroprocessing operations at refineries. Hydrodesulfurization is one of the important reactions involved in hydroprocessing. Transition metal sulfides have excellent properties in terms of sulphur removal. Molybdenum based catalysts have been used extensively in the petroleum industry for hydrotreating heavy oil fractions. Supported molybdenum based catalysts suffer strong deactivation in the traditional hydrotreating process due to the deposition of carbonaceous components on the surface of the catalyst when they are used in conventional fixed bed reactors. Unsupported catalysts have higher catalytic activity with better metal dispersion. Laboratory experiments were conducted in which micro/nano size unsupported molybdenum catalysts were synthesized from a water/oil emulsion. The catalysts were prepared in a continuous mode for online application to hydroprocessing or in situ upgrading. Dispersed molybdenum catalysts are more suitable for processing heavier feeds because they are less prone to deactivation. Also, their submicron size ensure high activities due to a large specific surface area. They are also sufficiently small to be readily dispersed in the residual oil. 4 refs., 1 tab., 2 figs.

The effects of different oil spill cleanup technologies on body burden and biomarkers in Arctic marine organisms - a laboratory study

Energy Technology Data Exchange (ETDEWEB)

Faksness, Liv-Guri; Hansen, Bjorn Henrik; Nordtug, Trond [SINTEF Materials and Chemistry (Norway)], email: livgurif@sintef.no; Borseth, Jan Fredrik; Baussant, Thierry; Tandberg, Anne Helene S.; Ingvarsdottir, Anna; Aarab, Nadia [IRIS Biomiljo (Norway); Altin, Dag [Altins BioTrix (Norway)

2011-07-01

This paper studies the effects and toxicity of a water soluble fraction (WSF) of oil versus chemically dispersed oil and also of WSF versus the underlying water after in situ burning (ISB). The applications of exposure concentrations were based on monitoring of WSF in the water column during an offshore field experiment. A continuous flow-through system for the dispersant experiments was set up and an Arctic amphipod was used as the test species. Seawater and gammarids were also used as samples for chemical and biological analyses. Good correlation with the data was presented by chemical analysis of the water samples. However, more PAHs (Polycyclic Aromatic Hydrocarbons) were measured in the gammarids exposed to oil mixed with dispersant than in those exposed to oil alone. On the other hand, a system was developed to allow water sampling after ISB and samples of seawater and of oil prior to, and immediately after, ISB were collected and a chemical analysis was conducted. The result of the analysis was that there was no increase in toxicity in the underlying water after ISB.

The effects of different oil spill cleanup technologies on body burden and biomarkers in Arctic marine organisms - a laboratory study

International Nuclear Information System (INIS)

Faksness, Liv-Guri; Hansen, Bjorn Henrik; Nordtug, Trond; Borseth, Jan Fredrik; Baussant, Thierry; Tandberg, Anne Helene S.; Ingvarsdottir, Anna; Aarab, Nadia; Altin, Dag

2011-01-01

This paper studies the effects and toxicity of a water soluble fraction (WSF) of oil versus chemically dispersed oil and also of WSF versus the underlying water after in situ burning (ISB). The applications of exposure concentrations were based on monitoring of WSF in the water column during an offshore field experiment. A continuous flow-through system for the dispersant experiments was set up and an Arctic amphipod was used as the test species. Seawater and gammarids were also used as samples for chemical and biological analyses. Good correlation with the data was presented by chemical analysis of the water samples. However, more PAHs (Polycyclic Aromatic Hydrocarbons) were measured in the gammarids exposed to oil mixed with dispersant than in those exposed to oil alone. On the other hand, a system was developed to allow water sampling after ISB and samples of seawater and of oil prior to, and immediately after, ISB were collected and a chemical analysis was conducted. The result of the analysis was that there was no increase in toxicity in the underlying water after ISB.

SO2 pollution of heavy oil-fired steam power plants in Iran

International Nuclear Information System (INIS)

Nazari, S.; Shahhoseini, O.; Sohrabi-Kashani, A.; Davari, S.; Sahabi, H.; Rezaeian, A.

2012-01-01

Steam power plants using heavy oil provided about 17.4%, equivalent to 35.49 TWh, of electricity in Iran in 2007. However, having 1.55–3.5 weight percentage of sulfur, heavy oil produces SO 2 pollutant. Utilization of Flue Gas Desulfurization systems (FGD) in Iran's steam power plants is not common and thereby, this pollutant is dispersed in the atmosphere easily. In 2007, the average emission factor of SO 2 pollutant for steam power plants was 15.27 g/kWh, which means regarding the amount of electricity generated by steam power plants using heavy oil, 541,000 Mg of this pollutant was produced. In this study, mass distribution of SO 2 in terms of Mg/yr is considered and dispersion of this pollutant in each of the 16 steam power plants under study is modeled using Atmospheric Dispersion Modeling System (ADMS). Details of this study are demonstrated using Geographical Information System (GIS) software, ArcGIS. Finally, the average emission factor of SO 2 and the emission of it in Iran's steam power plants as well as SO 2 emission reduction programs of this country are compared with their alternatives in Turkey and China.

Comparative evaluation of online oil and gas monitor; Avaliacao de monitores de teor de oleo e graxa em linha

Energy Technology Data Exchange (ETDEWEB)

Louvisse, Ana Maria Travalloni; Pereira Junior, Oswaldo de Aquino; Jesus, Rafael Ferreira de; Santos, Lino Antonio Duarte dos; Lopes, Humberto Eustaquio [PETROBRAS, Rio de Janeiro, RJ (Brazil)

2004-07-01

Petroleum is predominantly recovered in form of water in oil emulsions, which are stabilised by petroleum resins and asphaltenes, the colloidal disperse components of crude oil. The water phase, separated during the production process, consists of a dilute oil in water emulsion, commonly called produced water.There are a wide variety of methods for determination of oil in produced water that are commercially based on a number of technique. On line continuously monitoring shall be particularly useful in providing information to assist in optimising the separation process and also to attend the environmental legislation for discharge the produced water. There are a wide variety of on line oil in water monitors that are commercially available based on a number of technique. In this paper, a comparative evaluation was made between some methods of on line oil in water detecting. These are light scattering and ultraviolet fluorescence technique. A brief description of the optical methods will be discussed and some of associated problems and limitation are pointed. The work was done in a specific experimental set up that allows the simultaneous pumping of crude oil and water through a calibrated restriction in a pipe has been used. A permanent pressure drop induced by the restriction leads to the dispersion of the oil droplets in the water phase. The monitors based on light scattering technique tested show good agreement between monitor reading and the oil dispersion used. Otherwise for ultraviolet fluorescence based monitors show a significant effect of the variation of oil type. (author)

Hopane, a new chemical tool for measuring oil biodegradation

International Nuclear Information System (INIS)

Butler, E.L.; Douglas, G.S.; Steinhauer, W.G.; Prince, R.C.; Aczel, T.; Hsu, C.S.; Bronson, M.T.; Clark, J.R.; Lindstrom, J.E.