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1.
Nearly all crude oils and some heavier refined products form stable water-in-oil (w/o) emulsions when spilled and weathered at sea. Breaking these emulsions and discarding the separated water allow more oil to be recovered and stored by OSRVs (Oil Spill Recovery Vessels) and make the handling of oily waste easier due to viscosity reduction. This study was conducted to determine whether a combination of heat and emulsion breaker is more effective than either technique used alone. The results will be used to prepare guidelines for treatment of w/o emulsions and planning of large-scale tests.A bench-scale laboratory study was carried out using emulsions prepared from different crude oil residues (BCF-17, Alaskan North Slope and Bonny Light) and a Bunker C fuel oil/gas oil blend (IF-80). Tubes containing w/o emulsions, with or without emulsion breaker added, were partially submerged in a water bath at different temperatures to simulate the heating system of the recovered oil tanks onboard the OSRVs. The effectiveness of the emulsion breaking was measured by recording settled water over a 24 h period. The results showed that:
  • •• The stability of a w/o emulsion and its response to heat and emulsion breaker is highly dependent on different characteristics of the oil from which it is formed.
  • •• Stable w/o emulsions that can be slowly broken by heat alone were, in general, broken much more rapidly if emulsion breaker was added in addition to heat.
  • •• The w/o emulsions formed from relatively paraffinic crude oil (e.g. ANS) exhibit faster breaking rates than w/o emulsions formed from crude oils with high asphaltene content, such as BCF-17.
  • •• All w/o emulsions formed from the crude oil residues could be broken by the application of moderate amounts of heat. W/o emulsions produced from Bunker C/Diesel oil blend were not broken at all by relatively high heat inputs (up to 100°C) and required both the addition of heat and emulsion breaker to obtain partially breaking.
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2.
This paper focuses on the cost recovery issues arising through the operation of the International Oil Pollution Compensation Fund (IOPC) and administrative matters which arose following the Braer and Sea Empress oil tanker pollution incidents in the UK. Each of these oil spills brought very different problems.Any major oil spill will have prolonged economic and social consequences for the communities affected. Membership of the International Oil Pollution Compensation Fund (IOPC Fund) will do much to soften the impact as regards economic damage. However, the operation of the Fund brings difficulties which may not have been considered by the administration prior to the spill. Some of the difficulties are foreseeable.It covers details of the international compensation and liability regimes, it considers a number of administrative consequences and highlights seven lessons that have been learned in the UK in the light of recent experience. These lessons are:
  • •Claims may not be paid quickly or in full.
  • •Claimants will need advice and government involvement.
  • •Action by the government may be needed to complement the IOPC Fund.
  • •Governments have to balance their obligations as a member state with the needs of claimants.
  • •It is better for claimants to keep matters out of court for as long as possible.
  • •Administrative consequences will continue for a long time after the oil has been cleared from the shoreline.
  • •Each major oil spill brings different cost recovery problems and will also bring demands ‘to learn the lessons’.
In much the same way as contingency plans are regularly tested, each state party to the regime would be wise, from time to time, to think through the likely scenarios so as to better prepare themselves in the light of experiences elsewhere. The United Kingdom has had rather more experience in recent years than it would have wished!  相似文献   

3.
Based on a study carried out by the Versuchsanstalt für Wasserbau und Schiffbau, Berlin – VWS for the German Environmental Agency, this report represents an attempt to summarize the knowledge in the Federal Republic of Germany and world-wide concerning the control of hazards from discharged oil and other liquid chemicals after casualties on and in the hydrosphere. Because of technical reasons, control measures can be classified into passive and active types; this classification has been adopted for this report in the following order:
  • •Part 1: Passive mechanisms: Booms and barriers.
  • •Part 2: Active mechanisms: Recovery devices.
  • •Part 3: Other means: Dispersion.
  • •Part 4: Control of sinking and/or sunken chemicals.
Part 1 not only evaluates the behaviour of liquid chemicals on water, but also considers the physical fundamentals underlying the functioning of booms and barriers. Some widely used definitions and relations (such as the relationship between the blocking of liquid chemicals and boom draught or efficiency) will be refined. The discussion of the physical fundamentals is presented in the broadest sense and concludes with practical advice on the deployment of booms.Part 2 attempts to standardize recovery devices based on the application of fundamental physical principles. Four classes were identified and have been used to classify pick-up devices. Once again basic physical fundamentals have been presented in a way that facilitates deductions on application possibilities. The evaluation showed that practically only those methods that utilize adhesion and “hole-in-the-water” principles can be operated with sufficient efficiency which, in turn, reflects the world-wide state-of-the-art in equipment development. Special attention has been paid to hybrid systems which utilize both passive and active methodologies.In Part 3, the basics of dispersion of oil and other floating liquid chemicals are considered. It can be shown that mechanical dispersion has the same effect as its chemical counterpart. This relationship recognizes the necessity for applying a mechanical agitator for using dispersants effectively. This strategy calls into question the efficiency of chemical dispersion.Part 4 deals with the behaviour and control options for sinking and/or sunken liquid chemicals. Contrary to the general opinion that liquid chemicals which have disappeared from the surface cannot be controlled, it has been found that, under certain conditions, even these chemicals can be “herded” and recovered. It will be shown that practically the same techniques can be applied to submerged chemicals as has been used for the recovery of floating hazardous substances.  相似文献   

4.
At an excitation wavelength of 320 nm, the ultraviolet fluorescence (UVF) spectra emitted by reference oils dispersed in seawater with mineral fines yielded two important results:
  • (1)Resuspended negatively-buoyant oil–mineral aggregates (OMAs) exhibited maximum fluorescence at an emission wavelength of 450 nm and,
  • (2)the hydrocarbons dispersed and/or dissolved in the seawater that remained after the aggregates had settled out exhibited maximum fluorescence at 355 nm.
Data from UVF analysis (450 nm emission) and microscopical observations of seven reference oils suggest that higher-viscosity oils are less likely to form aggregates with mineral fines. This decline in OMA formation with increased oil viscosity could be predicted from a decrease in the ratio of emission at 450–355 nm. The data suggest that direct UVF spectroscopy of dispersed/dissolved oil and OMAs in seawater can be used to predict and verify the extent of OMA formation.  相似文献   

5.
Environmentally friendly use of non-coal ashes in Sweden   总被引:1,自引:0,他引:1  
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6.
7.
This paper discusses processes and factors for estimating time period windows of in situ burning of spilled oil at sea. Time-periods of in situ burning of Alaska North Slope (ANS) crude oil are estimated using available data. Three crucial steps are identified. The First Step is to determine the time it takes for the evaporative loss to reach the known or established limitation for evaporation and compare this time-period with estimated time of ignition at the ambient wind and sea temperatures. The Second Step is to determine the water up-take of the spilled oil and compare it with the known or established limitation for water-in-oil content. The Third Step is to determine the necessary heat load from the igniter to bring the surface temperature of the spilled oil to its flash point temperature so that it will burn at the estimated time period for ignition of the slick.  相似文献   

8.
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10.
Synthesis of sodium alginate-g-poly(acrylamide-co-N-methylacrylamide) [S-III], sodium alginate-g-poly(N-methylacrylamide-co-N,N-dimethylacrylamide) [S-II], sodium alginate-g-poly(acrylamide-co-N,N-dimethylacrylamide) [S-I]. Sodium alginate-g-poly(N,N-dimethylacrylamide) [SAG-g-PDMA] and sodium alginate-g-poly(acrylamide) [SAG-g-PAM] were prepared by solution polymerization technique using potassium peroxydisulfate as the initiator at 70?°C in water medium. The graft copolymers were characterized by FTIR and NMR (1H and 13C) spectroscopy, SEM and XRD studies. All the five graft copolymers were used to remove Pb(II) ions from the aqueous solution and also in flocculation studies of kaolin clay (1.0 wt%), silica (1.0 wt%) and iron ore slime (0.25 wt%) suspensions. A comparative studies of all the five graft copolymers were also made in both the two cases. The Pb(II) ion removal capacity of all the graft copolymers follows the order S-III?>?SAG-g-PAM?>?S-II?>?SAG-g-PDMA?>?S-I. But the flocculation performance of the graft copolymers follows the order S-II?>?S-I?>?S-III?>?SAG-g-PDMA?>?SAG-g-PAM. S-III was also used for the competitive metal ion removal with Hg(II), Cd(II), Cu(II) and Zn(II). Pb(II) adsorption of S-III (the best Pb(II) ion adsorber) follows pseudo second order rate equation and Langmuir adsorption isotherm.  相似文献   

11.
12.
In situ burning of inland and upland habitats is an alternative oil spill cleanup technique that, when used appropriately, may be more environmentally acceptable than intrusive manual, mechanical, and chemical treatments. There have been few published reports documenting the environmental effects of in situ burning in inland and upland habitats. Thus, this study, sponsored by the American Petroleum Institute, used two approaches to increase the knowledge base and improve the appropriate use of in situ burning: (1) detailed review of published and unpublished in situ burn case histories for inland and upland spills; and (2) summaries of fire effects and other information from the literature on fire ecology and prescribed burning. Thirty-one case histories were summarized to identify the state of the practice concerning the reasons for burning, favorable conditions for burning, and evaluations of burn effects. The fire ecology and effects summaries included information from the extensive knowledge base surrounding wildfire and prescribed burning (without oil) as a natural resource management tool, as well as fire tolerance and burning considerations for dominant vegetation types of the United States. Results from these two approaches should improve the application of in situ burning for inland and upland spills.  相似文献   

13.
This research note summarizes Spartina alterniflora and Sagittaria lancifolia sensitivity to oiling and in situ burning of applied oil. Experimental plots (2.4 m × 2.4 m × 0.6 m) were constructed in salt and freshwater marsh habitats and South Louisiana Crude (SLC) applied (2 l m−2) to stems and leaves of marsh plants of oil and oil/burn treatment plots. Burning was initiated mid-August when winds were calm and a 15-25 cm floodwater layer covered the marsh substrate. Vegetative responses (stem density, height, carbon assimilation and biomass production) were measured for approximately one year following the in situ burns. Application of oil and burning of SLC only had short-term detrimental effects on salt and freshwater marsh vegetation. About one year after burns, vegetative responses measured in oiled and oiled/burned plots approached or exceeded control (no oil or burn) values. Field results suggest, under our experimental conditions, in situ burning of spilled oil in S. alterniflora and S. lancifolia marshes may be a remediation operation to consider.  相似文献   

14.
Polyaniline (PANI) and Ag/PANI nanoporous composite were prepared by an oxidative polymerization method. The oxidation process of PANI nanoparticles was occurred using (NH4)2S2O8 while the oxidation process of Ag/PANI nanoporous composite was occurred using AgNO3 under the effect of artificial radiation. The structural, morphological, and optical properties of the PANI and Ag/PANI nanoporous structures were studied using different characterization tools. The results confirm the formation of polycrystalline nanoporous PANI and spherical nanoporous composite of Ag/PANI particles. Antibacterial activity tests against gram-positive bacteria, Bacillus subtilis and Staphylococcus aureus, and gram-negative bacteria, Escherichia coli, and Salmonella species were carried out using different concentrations of PANI nanoparticles and Ag/PANI nanoporous composites. PANI has not antibacterial effect against all studied pathogens. In contrast, Ag/PANI nanoporous composites possessed antibacterial activity that is identified by the zone of inhibition. The inhibition zones of bacteria are in order; Salmonella species?>?S. aureus?>?B. subtilis?>?E. coli. The inhibition zones of all bacteria increased with increasing concentrations of Ag/PANI nanoporous composites from 200 to 400 ppm then decreased with further increasing of the dose concentrations to 600 ppm. Finally, a simplified mechanism based on the electrostatic attraction is presented to describe the antimicrobial activity of Ag/PANI nanoporous composite.  相似文献   

15.
An experimental technique has been developed to study systematically the ignition, flame spread and mass burning characteristics of liquid fuels spilled on a water bed. The final objective of this work is to provide a tool that will serve to assess a fuel's ease of ignition, spread and sustaining a flame, thus, helping to better define the combustion parameters that affect in situ burning of oil spills.  相似文献   

16.
A bibliometric analysis based on the Science Citation Index Expanded (SCI-EXPANDED) from the Web of Science was carried out to provide insights into research activities and tendencies of the global biodiesel from 1991 to 2015. The document type and language, characteristics of publication outputs, Web of Science categories, journals, countries, institutions, author keyword and most cited articles were emphasized. The results indicated that annual output of the related scientific articles increased steadily. The top six categories focus on different aspects of biodiesel research. Bioresource Technology and Fuel were the two most frequent journals in the field of biodiesel research. The USA took a leading position and had the highest h-index (108) out of 122 countries/territories, followed by China and Brazil. Finally, author keywords and most cited articles were analyzed, indicating that microalgae, Jatropha curcas, vegetable oil and waste cooking oil are the most general raw materials for biodiesel production.  相似文献   

17.
The fermentation conditions for poly(l-lactide) (PLA)-degrading enzyme production by Amycolatopsis orientalis ssp. orientalis were statistically optimized by response surface methodology. The optimal value of the most important factors was 0.39 % PLA and 0.34 % gelatin for 2.81 days of cultivation. Under these conditions, the model predicted a PLA-degrading activity of 155.30 U/l. The verification showed the production amount of 154.2 U/l. The crude enzyme from A. orientalis ssp. orientalis showed potent PLA-degrading ability, which is efficient for the biological recycling of PLA. Up to 4,000 mg/l of PLA granule was completely degraded within 5 days at 45 °C by the crude enzyme. l-lactic acid (600 mg/l) was obtained as a degradation product of PLA after only 2 h of incubation. The results indicated that the crude PLA-degrading enzyme from A. orientalis ssp. orientalis has the potential to degrade PLA to lactic acid for the recycling of PLA industry and waste disposal.  相似文献   

18.
Based on pre-experimentation, three ornamental plants, Mirabilis jalapa, Impatiens Balsamin (I. Balsamin) and Tagetes erecta L., were selected as target plants to study the phytoextraction of chromium (Cr) in tannery sludge irrigated with four treatments according to Cr concentration gradient [Control (CK); 20.50 × 103 mg kg?1 (T1); 51.25 × 103 mg kg?1 (T2); 102.50 × 103 mg kg?1 (T3)]. Results of pot experiments showed that the biomass of Mirabilis jalapa and Tagetes erecta L. had no significant differences among the four treatments, while I. Balsamin showed a decline trend in the biomass with the increase of Cr concentration, probably due to some extent to the poisoning effect of Cr under treatment T2 or T3. Mirabilis jalapa accumulated Cr concentration, with 408.97, 124.97, 630.16 and 57.30 mg kg?1 in its roots, stems, leaves and inflorescence, respectively. The translocation factor and the bioaccumulation coefficient of Mirabilis jalapa are each greater than 1, indicating that Mirabilis jalapa has the strong ability to tolerate and enrich Cr by biological processes. Comparing accumulation properties of the three ornamental plants, in the amount and allocation, Mirabilis jalapa showed the highest phytoextraction efficiency and could grow well at the high Cr concentration. Our experiments suggest that Mirabilis jalapa is the expected flower species for Cr removal from tannery sludge.  相似文献   

19.
In situ burning is being utilized in the United States to remove oil from inland oil spills, usually when physical recovery is not feasible. Studies have found that habitats may recover from the effects of burning in less than a year under optimal conditions but recovery may take much longer. Policies authorizing the use of in situ burning across the US are very inconsistent. Some states use it routinely, but others do not allow it. Inland in situ burning can be a useful response tool and the federal government needs to issue more guidance to the states. Responders also need to collect more data on the environmental impacts of burning.  相似文献   

20.
For characterisation of landscapes in north-eastern Estoniaaffected by alkaline oil shale fly ash and cement dust the zonation-method based on average annual (C y) and short-termconcentrations of pollutants in the air was used, as well as on deposition loads of dust and Ca2+. In the overground layer of atmosphere the zones with different air pollution loads were distinguished. A comparative analysis of pollution zones characteristics and biomonitoring data revealed that for sensitive lichen the dangerous level of alkaline dust in the air, introducingthe degradation of Sphagnum sp. at the level of C y of dust 10–20 g m-3 and at 0.5–1 hr maximums 100–150 g m-3. For Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) this limited concentration (decline of growth parameters) of cement dust is correspondingly following: 30–50 g m-3 and 150–500 g m-3, in case of fly ash the limit level of C y amounting 100 g m-3. Daily deposition load of Ca2+ should not exceed approximately 4.5–15 mg m-2 for lichen; for conifers the harmful pollution load is higher – >22 mg m-2.  相似文献   

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