1、Designation: F3251 17Standard Test Method forLaboratory Oil Spill Dispersant Effectiveness Using theBaffled Flask1This standard is issued under the fixed designation F3251; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year o
2、f last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the procedure to determine theeffectiveness of oil spill dispersants on various oils in thel
3、aboratory. This test method is not applicable to other chemicalagents nor to the use of such products or dispersants in openwaters.1.2 This test method covers the use of the Baffled Flask testapparatus and does not cover other apparatuses nor are theanalytical procedures described in this report dir
4、ectly appli-cable to such procedures.1.3 The test results obtained using this test method areintended to provide baseline effectiveness values used tocompare dispersants and oil types under conditions analogousto those used in the test.1.4 The test results obtained using this test method areeffectiv
5、eness values that should be cited as test values derivedfrom this standard test. Dispersant effectiveness values do notdirectly relate to effectiveness at sea or in other apparatuses.Actual effectiveness at sea is dependent on sea energy, oil state,temperature, salinity, actual dispersant dosage, an
6、d amount ofdispersant that interacts with the oil.1.5 The decision to use or not use a dispersant on an oilshould not be based solely on this or any other laboratory testmethod.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsi
7、bility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.7 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in
8、 the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2F2059 Test Method for Laboratory Oil Spill DispersantEffectiveness Using
9、 the Swirling Flask2.2 EPA Standard:3SW-846 Method 8270D, Revision 4 Semivolatile OrganicCompounds by Gas Chromatography/Mass Spectrometry(GC/MS)3. Terminology3.1 Definitions:3.1.1 effectiveness, nthe capability of producing a desiredresult which is this case is the dispersion of oil into water.3.1.
10、1.1 DiscussionEffectiveness is given here as the per-cent of oil dispersed into the water column as a result ofdispersant action and energy.3.1.2 trypsinizing, nthe process of cell dissociation usingtrypsin, an enzyme which breaks down proteins, to dissociateadherent cells from the vessel in which t
11、hey are being cultured.3.1.2.1 DiscussionThis test method uses only the vesseldesigned for that process (with the addition of a withdrawaltube).4. Summary of Test Method4.1 The dispersant is pre-mixed with oil and placed on waterin a test vessel. The test vessel is agitated on a moving tableshaker.
12、At the end of the shaking period, a settling period isspecified and then a sample of water taken. The oil in the watercolumn is extracted from the water using a dichloromethanesolvent and analyzed using gas chromatography.4.2 The extract is analyzed for oil using a gas chromato-graph equipped with a
13、 flame ionization detector (GC-FID).Quantification is by means of the internal standard method.1This test method is under the jurisdiction of ASTM Committee F20 onHazardous Substances and Oil Spill Response and is the direct responsibility ofSubcommittee F20.13 on Treatment.Current edition approved
14、April 15, 2017. Published May 2017. DOI: 10.1520/F3251-172For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Ava
15、ilable from United States Environmental ProtectionAgency (EPA), WilliamJefferson Clinton Bldg., 1200 Pennsylvania Ave., NW, Washington, DC 20460,http:/www.epa.gov; https:/www.epa.gov/sites/production/files/2015-12/documents/8270d.pdfCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, W
16、est Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World
17、Trade Organization Technical Barriers to Trade (TBT) Committee.1Effectiveness values are derived by comparison with a cali-brated set of effectiveness values obtained at the same time andby the same method.5. Significance and Use5.1 A standard test is necessary to establish a baselineperformance par
18、ameter so that dispersants can be compared, agiven dispersant can be compared for effectiveness on differentoils, and at different oil weathering stages, and batches ofdispersant or oils can be checked for effectiveness changeswith time or other factors. This test method provides a secondtest at hig
19、her mixing energy in addition to the Swirling Flask(Test Method F2059).5.2 Dispersant effectiveness varies with oil type, sea energy,oil conditions, salinity, and many other factors. Test resultsfrom this test method form a baseline at high mixing energy,but are not to be taken as the absolute measu
20、re of performanceat sea. Actual field effectiveness could be more or less than thisvalue.5.3 Many dispersant tests have been developed around theworld. This test has been developed in recent years andprovides higher mixing energies compared to other laboratoryscale tests.6. Interferences and Sources
21、 of Error6.1 Interferences can be caused by contaminants, particu-larly residual oil or surfactants in solvents, on glassware, andother sample processing apparatus that lead to discrete artifactsor elevated baselines in gas chromatograms. All glasswaremust be thoroughly cleaned. The cleaning process
22、 includesrinsing with dichloromethane to remove the oil, followed byrinsing three times each with tap water, purified water (reverseosmosis or similar), and acetone. Once cleaned, precautionsmust be taken to minimize contact of the glassware withsurfactants to prevent undesired interferences.6.2 Dis
23、persant effectiveness is very susceptible to energylevels. Table top shakers generally start and stop slowly.Shakers that start motion rapidly and stop suddenly impart ahigh energy to the system and thus cause more dispersion thanwould be the case with a normal shaker. Furthermore, thisvariation wou
24、ld not be repeatable. The shaker table usedshould be observed for rapid movements or stops to ensure thatit is usable for these tests. The rotational speed of the shakershould be checked with a tachometer every week before use.6.3 The flasks used in this test are tapered and the energylevel varies w
25、ith the amount of fill and variation in dimensions.6.4 The output is highly sensitive to the volume of oil,water, and extractant. All pipets and dispensers should becalibrated frequently and verified daily when in use.6.5 The use of positive displacement pipets is mandatory forall controlled volumes
26、 of microlitre quantities. Use of volumedisplacement pipets will result in erroneous results due to theviscosity of the dispersants and oils, the variable viscosity ofthe oils to be tested (some semi-solid), and the density ofdichloromethane.6.6 The order of addition of the dispersant and oil haseff
27、ects on the accuracy of results, as the dispersant may interactwith the vessel walls if added first, thereby reducing thequantity available in the premix. It is therefore important to addoil to the vessel first, and add the dispersant directly to the oil.Asecond addition of oil is suggested simply b
28、ecause it is easierto control a large volume of oil than a minute volume ofdispersant when attempting to achieve a specific ratio of 25:1.6.7 Following dispersant addition, vigorous mixing is re-quired to homogenize the sample. Sharp, manual strokes aresuggested for light oils, while very heavy oils
29、 may requirestirring with a clean glass rod or spatula.6.8 There are indications that mixing will vary with timefollowing preparation of the premixed dispersant/oil combina-tions. As a precaution it is highly recommended that the testingshould be completed as soon as practical following preparationo
30、f the premix, and not stored for use at a later time.6.9 Since the performance of the dispersant is affected bysalinity, the salt water should be thoroughly mixed, stored inairtight containers, and checked with a salinity meter prior touse.6.10 Temperature is a factor in dispersion, so it is importa
31、ntthat all components (salt water, pre-mix, and temperature-controlled chamber) are stable at 20C (or the chosen operatingtemperature) before starting.6.11 Care should be taken when applying the oil to thesurface so that mixing does not occur. The oil should gentlyglide across the water to form a sl
32、ick. If the oil streams out intothe water, the agitation can disperse the oil, increasing theamount of oil dispersed and erroneously raising the finaldispersion result.6.12 Dispersion effectiveness generally declines with in-creased evaporation of oil components. Care should be taken toavoid unneces
33、sary exposure of the oil and dispersant/oilpremix before and during the test procedure to protect sampleintegrity and minimize variability related to oil weathering.Special care should be taken to minimize the time to apply thedispersant-oil premix to all six vessels in a test run.6.13 The procedure
34、 is time critical for the elements ofmixing, settling, and sampling. Care should be taken to adhereto the times indicated in the procedure for both the mixing andsettling element, as variations in energy input, and especiallytime allowed for droplet rise, can impact results. Since thewater samples c
35、annot be sampled simultaneously, this stepmust be performed as quickly as possible, to reduce thedifference in settling times experienced by the samples in thetest run.6.14 Analysis of the gas chromatograph-detectable TotalPetroleum Hydrocarbon (TPH) content is subject to variabilityin GC operation
36、and repeatability (Test Method F2059:EPA8270D). Therefore, it is imperative that a rigorous qualityassurance program is in place to ensure the GC is functioningproperly and valid results are obtained.6.15 Care should be taken to determine the baseline in avalid and repeatable manner for both samples
37、 and calibrationsets.F3251 1726.16 The accuracy and repeatability of the test can beverified and compared using standard oil and dispersantsamples.7. Apparatus7.1 Modified Baffled Trypsinizing Flask, used as the testvessel. A side spout is added to a trypsinizing flask to enablesampling from the wat
38、er column with minimal disturbance ofthe resurfaced oil. A modified 150 mL glass screw-cappedtrypsinizing flask with baffles (for example, Wheaton No.355394 or equivalent) fitted with a 2-mm bore polytetrafluo-roethylene (PTFE) stopcock and glass tubing, the center ofwhich is no more than 1.3 cm fro
39、m the bottom.4This vessel isillustrated in Fig. 1.7.2 Moving-Table Shaker, with an orbital motion of 25.4mm (1 in.) and fitted with flask holders. Ideally such shakersshould be operated inside temperature-controlled chambers. Ifsuch an enclosed chamber is not used, the measurement mustbe conducted i
40、nside temperature-controlled rooms.7.3 Gas Chromatograph (GC), equipped with a flame ion-ization detector is used for analysis. The column is a fusedsilica column.7.4 The following is a list of other necessary supplies.Suppliers of suitable units are footnoted. Equivalent suppliesare acceptable in e
41、very case. Quantities of supplies are given toconduct a full set of six samples and calibration set:7.4.1 Eighteen Crimp Style Vials, with aluminum/polytetrafluoroethylene (PTFE) seals, 12 by 32 mm,7.4.2 Twelve Baffled Flasks, 150-mL glass, modified asnoted above.47.4.3 Six Graduated Mixing Cylinder
42、s and Stoppers, 25-mLglass,7.4.4 Six Separatory Funnels and Stoppers, glass, 25-mL.7.4.5 Six Graduated Mixing Cylinders and Stoppers, glass,100-mL.7.4.6 Six Separatory Funnels and Stoppers, glass, 250-mL.7.4.7 Six Graduated Cylinders, glass, 50-mL.7.4.8 Six Dispenser or Glass Graduated Cylinders, 5-
43、 to25-mL.7.4.9 Positive Displacement Pipet, variable volume 20- to100-L.7.4.10 Positive Displacement Pipet, variable volume, 1-mLcapacity.4The sole source of supply of the apparatus known to the committee at this timeis Pro Science, Inc., 770 Birchmount Road, Unit 25, Scarborough, OntarioMIK5H3. If
44、you are aware of alternative suppliers, please provide this informationto ASTM International Headquarters. Your comments will receive careful consid-eration at a meeting of the responsible technical committee,1which you may attend.FIG. 1 The Baffled Flask Vessel with the Addition of a Stopcock and a
45、 Withdrawal TubeF3251 1737.4.11 Two Digital Timers,7.4.12 Dispenser or Graduated Cylinders, 20-mL and 5-mLvolumes, and7.4.13 One Plastic Carboy20-L.8. Reagents8.1 ReagentsWater purified by reverse osmosis or equiva-lent means is used for the test water. Dichloromethane isdistilled-in-glass grade. Fi
46、ne granular sodium chloride (or tablesalt, non-iodized) or reagent-grade sea salt mix (for example,SigmaAldrich or equivalent), is used for making the salt water.The chemical dispersant is used as supplied by the manufac-turer. Oil is used as received.9. Procedure9.1 Crude Oil Sample Storage and Pre
47、parationThe bulkoil as received is mechanically mixed to attain homogeneityprior to obtaining a working sample. Working samples arestored in clean, airtight containers. The working sample ismechanically shaken for 30 min at 20C (or the chosenoperating temperature) prior to removing a sub-sample fort
48、esting. When not in use, all samples should be stored in arefrigerator at approximately 5C.9.2 Dispersant Sample Storage and PreparationWhen notin use, samples should be stored in a refrigerator at 5C inopaque or amber containers. Prior to use, the sample isequilibrated to the temperature of the tes
49、t. The dispersant isthen manually shaken, vigorously, prior to sampling.9.3 Premix Sample PreparationA small amount of oil(approximately 1.0 mL) is weighed into a 5-mL amber vialwith PTFE-lined cap. Approximately 100 mg of dispersant isadded to the oil. Oil is added until a 1:25 ratio (by weight) ofdispersant to oil is achieved. The sample is well mixed bymanual shaking or stirring.9.4 Salt-Water PreparationGranular salt or sea salt mix isweighed and added to purified water (reverse osmosis (RO)filtration or equivalent) to obtain a 3.3 % (w/v) solution. Thewater t
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