1、Designation: F3045 151Standard Test Method forEvaluation of the Type and Viscoelastic Stability of Water-in-oil Mixtures Formed from Crude Oil and Petroleum ProductsMixed with Water1This standard is issued under the fixed designation F3045; the number immediately following the designation indicates
2、the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTEThe numbering in Section 3 was editorially corrected in
3、 May 2016.1. Scope1.1 This test method covers a procedure to determine thewater-in-oil emulsification tendencies and stabilities in thelaboratory. The results of this test method can provide oilbehavior data for input into oil spill models.1.2 This test method covers a specific method of determin-in
4、g emulsion tendencies and does not cover other procedureswhich may be applicable to determining emulsion tendencies.1.3 The test results obtained using this test method areintended to provide baseline data for the behavior of oil andpetroleum products at sea and input to oil spill models.1.4 The tes
5、t results obtained using this test method can beused directly to predict certain facets of oil spill behavior or asinput to oil spill models.1.5 The accuracy of the test method depends very much onthe representative nature of the oil sample used. Certain oilscan form a variety of water-in-oil types
6、depending on theirchemical contents at the moment a sample is taken. Other oilsare relatively stable with respect to the type formed1.6 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.7 This standard does not purport to addres
7、s all of thesafety concerns, if any, associated with its use. It is theresponsibility 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.2. Summary of Test Method2.1 Oil is mixed with 33 (3.3%) sa
8、line water for 12 h ina standard rotating apparatus. The resulting mixture is charac-terized after this shaking period.2.2 The resulting mixture as created in step 2.1, is charac-terized visually, by measuring water content and by rheologicalmeasurements. The mixture is then classified as a stable,m
9、eso-stable, unstable emulsion or an entrained water mixture.Each of these four types of mixtures has different characteris-tics affecting the oils behavior once spilled.3. Terminology3.1 Definitions:3.1.1 complex modulusOne of the results of viscoelasticmeasurement, a measure of the resistance of a
10、viscoelasticsubstance to flow under an applied dynamic stress, combiningboth the non-reversible (viscous) flow of the test substance andthe reversible (elastic) deformation of the test substance.3.1.2 emulsionA type of colloid, specifically, a dispersionof small droplets of one liquid in another.3.1
11、.2.1 meso-stable emulsionsEmulsions which lack oneor more of the compositional factors necessary to form a stableemulsion, but which are sufficiently stable to persist for shortperiods, typically a few days.3.1.2.2 stable emulsionsEmulsions that persistindefinitely, consisting of fine droplets with
12、a rigid filminterface which resists coalescence.3.1.2.3 unstable emulsionsMixtures of water and oilwhich resolve rapidly into two phases, usually within a fewminutes to hours. There may be residual water remaining inlow percentages.3.1.2.4 water-in-oil emulsionAn emulsion consisting of acontinuous p
13、hase of oil containing a dispersed phase of water.3.1.3 entrained waterThis is not an emulsion but a me-chanical mixture of oil and water which has not separated dueto the physical properties of the water and oil.3.1.3.1 DiscussionTypically, the oil and water have simi-lar densities and the oil phas
14、e has a high viscosity.3.1.4 ragThe remnant of a broken water-in-oil emulsion.3.1.4.1 DiscussionRag will not reform an emulsion. Ragis thought to consist of tightly bound asphaltenes and resins.1This test method is under the jurisdiction of ASTM Committee F20 onHazardous Substances and Oil Spill Res
15、ponse and is the direct responsibility ofSubcommittee F20.16 on Surveillance and Tracking.Current edition approved Oct. 1, 2015. Published December 2015. DOI:10.1520/F304515E01.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.5 sta
16、bility indexAn index describing the stability of anemulsion.3.1.5.1 DiscussionIn this standard, it is calculated usingdata derived from rheological measurements.3.1.6 storage modulusOne of the results of viscoelasticmeasurement, a measure of the elastic (reversible) deformationbehavior of a viscoela
17、stic substance under an applied dynamicstress.4. Significance and Use4.1 A standard test is necessary to establish a behaviorpattern for spilled oils or petroleum products at different oilweathering stages.4.2 Water-in-oil mixtures vary with oil type and oil condi-tions such as weathering. Results f
18、rom this test method form abaseline, and usually are a measure of behavior at sea.4.3 This test has been developed over many years usingstandardized equipment, test procedures, and to overcomedifficulties noted in other test procedures.4.4 This test should be performed at the temperatures anddegrees
19、 of weathering corresponding to the spill conditions ofinterest.5. Interferences and Sources of Error5.1 Interferences can be caused by contaminants, particu-larly residual oil or surfactants on labware, and other samplehandling supplies and apparatus that lead to irregular results.All glassware mus
20、t be thoroughly cleaned. The cleaningprocess includes rinsing with dichloromethane to remove theoil, followed by rinsing three times each with tap water,purified water (reverse osmosis), and acetone. Once cleaned,precautions must be taken to minimize contact of the labwarewith contaminants to preven
21、t interferences.5.2 Emulsion formation is somewhat susceptible to energylevels. The rotational speed of the shaker should be checkedwith a tachometer every day. The specified direction of rotationshould be followed (vessel cap leads rotation on start-up).5.3 The specified fill volumes of the test ve
22、ssels must beobserved as the energy level varies with the amount of fill.5.4 Temperature is a factor in emulsification, so it isimportant that all components (salt water, pre-mix, and tem-perature controlled chamber) are stable at 15C or the selectedtest temperature, before starting.5.5 The handling
23、 of the samples after the mixtures areformed is important. Care must be taken to take a representa-tive sample. Excess water should be avoided when sampling.5.6 Since the test results may be affected by salinity,thorough mixing of the salt water is required. Salinity shouldbe verified using a salini
24、ty meter before use.5.7 Oils sources, especially crude oil sources, vary muchwith production time and conditions. Oil samples must betreated as unique and are not necessarily representative of thesource. Some oils are near the threshold of two differentwater-in-oil types. Depending on the actual con
25、ditions underwhich this oil was sampled, different results may occur. Otheroils are not as sensitive.5.8 Additives introduced in the production and transport ofoils can change their emulsification behavior. Some oils haveadded asphaltene suspenders or emulsion inhibitors. Thesemay significantly alte
26、r the outcome of this test. Information onthe oil treatment should be obtained before making the test.6. Apparatus6.1 2.2-litre fluorinated HDPE wide-mouth bottles, approxi-mately 24 cm in height and 6 cm in radius (Nalgene orequivalent), used as the test vessel. These vessels match theshaker as des
27、cribed below.6.2 Variable speed end-over-end rotary mixer capable ofmaintaining 55 RPM, with a radius of rotation of 15 cm (7.5cm from center of vessel) (Associated Design or equivalent).26.3 Automated Karl Fischer titration analyser, This deviceis used to measure the water content of the resulting
28、water-in-oil mixture.6.4 Rheometer, with a 35 mm parallel-plate geometry, ca-pable of functioning in forced-oscillation mode. This device isused to measure the rheological properties of the resultingwater-in-oil mixture.6.5 Circulating bath with a range from 0 to 25 C (60.1).6.6 Salinometer or water
29、 quality meter, SensIon 745 orequivalent.6.7 Oil mixing devices including a shaker for mixing thesmall samples prior to use and devices to mix the oil containedin drums.6.8 The following is a list of other necessary supplies.Equivalent supplies are acceptable.6.8.1 Disposable 30- and 1-mL plastic sy
30、ringes,6.8.2 20-L plastic carboy, stirring plate and stir bar.6.8.3 Spatulas and wide-mouth bottles for sample handlingand storage,7. Reagents37.1 ReagentsWater purified by reverse osmosis or equiva-lent means is used for the test water. Fine granular sodiumchloride or table salt, non-iodized, is us
31、ed for making the saltwater. The brine solution of 33 (3.3%) NaCl prepared fromsalt and purified water, is stored in a 20-L carboy at ambienttemperatures until needed. Fresh water may also be used forthe test to mimic non-saline conditions.2These devices are described in EPA standards for use in ext
32、raction tests: EPAMethod 1310 Extraction Procedure (EP) Toxicity Test Method And StructuralIntegrity Test, EPA Method 1311 Toxicity Characteristic Leaching Procedure(TCLP), and EPA 1312 Synthetic Precipitation Leaching Procedure (SPLP).Environmental Protection Agency 1200 Pennsylvania Avenue, N.W. W
33、ashington,DC 20460. http:/www3.epa.gov/3Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For Suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset,
34、 U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.F3045 15127.1.1 Oilis used as received, but is shaken for 30 minutesprior to use and is maintained at the test temperature of 15C.7.1.2 Karl Fischer reagent, 5 mg/mL H2O, singlec
35、omponent, pyridine free.7.1.3 Toluene, methanol and chloroform, reagent grade, assolvent for the Karl-Fischer titration.7.1.4 Dichloromethane and acetone, as clean-up solvents,and RO purified water8. Procedure8.1 Crude Oil Sample Collection and StorageThe bulk oilis mechanically mixed for 1 to 2 h p
36、rior to obtaining a workingsample. Working samples are stored in 2-L high-densitypolyethylene bottles with polypropylene screw closures. Theworking sample is mechanically shaken for 30 min at 15C orthe selected operating temperature prior to removing a sub-sample for testing. When not in use, all sa
37、mples should bestored in a temperature controlled room at 5C.8.2 Generating the water-in-oil mixtureIn summary,water-in-oil mixtures are formed in 2.2-litre fluorinated vesselson an end-over-end rotary mixer (Associated Design, VA orequivalent) at a rotational speed of 55 RPM.8.2.1 Each 2.2 L mixing
38、 vessel is filled with 600 mL ofwater, either salt or fresh water as selected for the test. Thewater should be at the test temperature at the time of addition.8.2.2 Oil is introduced at a ratio of 1:20 oil:water by adding30 mL of the test oil to the vessel.8.2.3 The vessels are sealed and mounted in
39、 the rotary mixersuch that the cap of each mixing vessel leads the direction ofrotation to maximize the turbulence of mixing.8.2.4 The rotary mixer and vessels are held at 15C or theselected operating temperature in a temperature controlled coldroom for the duration of the experiment. This temperatu
40、re(15C) or the selected operating temperature is the standardtemperature for measuring oil properties, If the predictedtemperatures the time of a spill are different the test should beperformed at those predicted temperatures as well. Testing atdifferent temperatures necessitate that the entire stud
41、y beperformed at the new chosen temperature.8.2.5 The vessels and their contents are allowed to stand for4 h to thermally equilibrate.8.2.6 The mixing is initiated using an electronic timerswitch. The vessels are mixed continuously for 12 h at arotation speed of 55 RPM.8.2.7 After 12 h mixing, the w
42、ater-in-oil mixtures arecollected from the vessels and transferred to appropriatelysized glass wide-mouthed jars for observation and analysis.8.2.8 The emulsions are stored in the cold room at 15C orthe selected operating temperature for one week, followed byadditional observation and analysis.8.2.9
43、 Each oil is tested in triplicate.8.2.10 The visual observations, viscosity, viscoelastic prop-erties and water content of the starting oil and the resultingwater-in-oil mixture are measured for comparison as outlinedin the procedures described below.8.3 Sampling and analysisA small sample is withdr
44、awnfrom each wide-mouth jar for further analysis as describedbelow. Analysis is performed twice, immediately after mixingand after one week.8.4 Sample Analysis for Water ContentWater content ismeasured using a Metrohm 784 KFP Titrino Karl Fischervolumetric titrator (or equivalent) and Metrohm 703 Ti
45、 Stand(or equivalent). The titre reagent is Aquastar Comp 5 (orequivalent) and the solvent is 1:1:2 methanol:chloroform:tolu-ene. A set of three measurements are made for each sample.8.5 Viscosity Measurement of oilsDynamic viscosities ofthe oils are measured at 15C using a VT550 with viscometerusin
46、g concentric cylinder geometry. The appropriate cup andspindle combination is selected on the basis of the validviscosity range for each type, as provided by the manufacturer.The highest suitable shear rate is selected from the manufac-turers guidance manual. The measurement protocol follows aone mi
47、nute ramp up to the target shear rate, holding for fiveminutes, then ramping back down to zero to evaluate thixot-ropy. The reported value for the oil is the average viscosityover the five minutes hold period. Triplicates are performed foreach sample.8.6 Viscoelastic Measurements of the water-in-oil
48、mixturesThe viscoelastic properties are determined on aThermoHaake RheoStress RS6000 rheometer with RheoWinsoftware (or equivalent) using 35 mm plate-plate geometry inforced oscillation mode. The sample stage height is set for a2.00-mm gap. The sample is measured at 15C in forcedoscillation mode usi
49、ng a stress sweep from 0.100 to 10.0 Pa ata frequency of one reciprocal second. Values of the complexmodulus, storage modulus, loss modulus, and tan () areobtained in the linear viscoelastic range (stress independentregion of the stress response curve). Samples are measured induplicate.8.7 Data recording of the measurementsThe visual obser-vations and the data on the water content and the viscoelasticmeasurements are recorded for the water-in-oil mixtures on thetest day following the 12-h mixing and again after one week.The water content and vis
