1、Designation: D 7261 08An American National StandardStandard Test Method forDetermining Water Separation Characteristics of DieselFuels by Portable Separometer1This standard is issued under the fixed designation D 7261; the number immediately following the designation indicates the year oforiginal ad
2、option 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.This standard has been approved for use by agencies of the Department of Defense.1
3、. Scope*1.1 This test method covers a rapid portable means for fieldand laboratory use to rate the ability of diesel fuels (both neatand those containing additives) to release entrained or emulsi-fied water when passed through fiberglass coalescing material.1.2 This test method is applicable to dies
4、el fuels such asD 975 Grade No. 1 and Grade No. 2 of all sulfur levels, andMIL-F-16884, naval distillate fuel (NATO F-76).NOTE 1This test method is similar to Test Method D 3948 which isapplicable to aviation turbine fuels.1.3 The values stated in SI units are to be regarded asstandard. No other uni
5、ts of measurement are included in thisstandard.1.4 This standard does not purport to address 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 regu
6、latory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 975 Specification for Diesel Fuel OilsD 1193 Specification for Reagent WaterD 3948 Test Method for Determining Water SeparationCharacteristics of Aviation Turbine Fuels by PortableSeparometerD 4057 Practice for Manual Sampl
7、ing of Petroleum andPetroleum ProductsD 4176 Test Method for Free Water and Particulate Con-tamination in Distillate Fuels (Visual Inspection Proce-dures)D 4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD 4306 Practice for Aviation Fuel Sample Containers forTests Affected by
8、Trace ContaminationD 4860 Test Method for Free Water and Particulate Con-tamination in Mid-Distillate Fuels (Clear and Bright Nu-merical Rating)D 6426 Test Method for Determining Filterability ofMiddle Distillate Fuel Oils2.2 Military Standard:MIL-F-16884 Fuel, Naval Distillate (NATO F-76)33. Termin
9、ology3.1 Definitions:3.1.1 Micro-Separometer rating (DSEP rating), na nu-merical value indicating the ease of separating emulsified waterfrom fuel by coalescence as affected by the presence of surfaceactive materials (surfactants) in the fuel.3.1.2 reference fluid, na reference fluid base to whichpr
10、escribed quantities of a known surface active agent havebeen added.3.1.2.1 DiscussionThe known surface active agent istypically bis-2-ethylhexyl sodium sulfosuccinate, commonlyreferred to as AOT, dissolved in toluene.3.1.3 surfactants, nin petroleum fuels, surface active ma-terials that could disarm
11、 (de-activate) filter separator (coalesc-ing) elements so that free water is not removed from the fuel inactual service.3.1.3.1 DiscussionTechnically, surfactants affect the in-terfacial tension between water and fuel which affects thetendency of water to coalesce into droplets or not.1This test met
12、hod is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.14 on Stability and Cleanliness of Liquid Fuels.Current edition approved July 1, 2008. Published August 2008. Originallyapproved in 2006. Last previous edition
13、approved in 2007 as D 726107.2For 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.3Available from Standardization
14、Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.4 strong surfact
15、ants, nin petroleum fuels, surfaceactive materials that disarm filter separator elements.3.1.4.1 DiscussionStrong surfactants can be refinery pro-cess chemicals left in the fuel or contaminants introducedduring transportation of the fuel.3.1.5 weak surfactants, nin petroleum fuels, surface ac-tive m
16、aterials that do not adversely affect the performance offilter separator elements in actual service.3.1.5.1 DiscussionWeak surfactants are typically certaintypes of additives used in fuels.3.2 Definitions of Terms Specific to This Standard:3.2.1 DSEP rating, nthe Micro-Separometer rating ofdiesel fu
17、els as measured by this test method.3.2.1.1 DiscussionThe “D” in DSEP stands for dieselfuel. (See 14.1 for more information.)3.2.2 reference fluid base, na distillate diesel fuel that hasbeen carefully cleaned in a prescribed manner to remove allsurface-active contaminants, and having a minimum DSEP
18、rating of 97.3.2.2.1 DiscussionThe reference fluid base should be adiesel fuel typical of fuels to be tested.3.3 Abbreviations:3.3.1 acalternating current3.3.2 AOTAerosol OT (see 8.1)3.3.3 C/Scollect sample3.3.4 dcdirect current3.3.5 MSEPMicro-Separometer3.3.6 DSEPMicro-SeparometerDiesel4. Summary o
19、f Test Method4.1 A 50 mL water/fuel sample emulsion is created in asyringe using a high-speed mixer. The emulsion is thenexpelled from the syringe at a programmed rate through astandard fiber-glass coalescer and the effluent is analyzed foruncoalesced water by a light transmission measurement.4.2 Th
20、e results are reported on a 0-to-100 scale to thenearest whole number, however the effective range of the testequipment is from 50 to 100. High ratings indicate that wateris easily coalesced, implying that the fuel is relatively free ofsurfactants.4.3 A test can be performed in 5 to 10 min.5. Signif
21、icance and Use5.1 This test method provides a measure of the presence ofsurfactants in diesel fuels, and can be performed in the field orin a laboratory. Like Test Method D 3948 used for jet fuel, thistest method can detect traces of some refinery treating chemi-cals left in fuel. It can also detect
22、 surface active substancesadded to or picked up by the fuel during handling from pointof production to point of use.5.2 Certain additives, which can act as weak surfactants,give a slightly reduced DSEP rating. Other substances whichare strong surfactants give much lower DSEP ratings.5.3 While filter
23、 separators have not been common in dieselfuel systems, they could become more prevalent with ULSDcontaining increased additive content to ensure clean, dry fuelsin new engine designs. Weak surfactants, with slightly reducedDSEP ratings, do not affect the ability of filter separators toseparate free
24、 water from the fuel. Strong surfactants give amuch lower DSEP rating and adversely affect the ability offilter separators to separate free water from the fuel.5.4 Results from this test method do not have a knownrelationship to the rate of water settling in tanks.5.5 The Micro-Separometer has a mea
25、surement range from50 to 100. Values obtained outside of those limits are undefinedand invalid.NOTE 2In the event a value greater than 100 is obtained, there is agood probability that light transmittance was reduced by material con-tained in the fuel used to set the 100 reference level. The material
26、 wassubsequently removed during the coalescing portion of the test, thus, theprocessed fuel had a higher light transmittance than the fuel sample usedto obtain the 100 reference level resulting in the final rating measuring inexcess of 100.6. Interferences6.1 Any suspended particles, whether solids
27、or water drop-lets or haze, in a fuel sample will interfere with this testmethod, which utilizes light transmission of a fuel sample afteremulsification with water and subsequent coalescence.6.2 Non-hydrocarbon components such as oxygenates, es-pecially alcohols, or emulsified water have not been ve
28、rifiedfor this test method and will likely interfere.7. Apparatus7.1 A Micro-Separometer4,5instrument is used to performthe test. The unit is portable and self-contained, capable ofoperating on an internal rechargeable battery pack or beingconnected to an ac power source using power cords which area
29、vailable for various voltages. Connection to an ac powersource will provide power to the unit and affect batteryrecharge. The accessories can be packed in the cover of thelockable case. There are two versions of the Micro-Separometer: the Mark V Deluxe and the upgraded version,Mark X.NOTE 3An extens
30、ive study was performed to verify that the Mark XMicro-Separometer gives equivalent results to the Mark V DeluxeMicro-Separometer. See Research Report RR: D021647.67.1.1 The Emcee Model 1140 Micro-Separometer Mark VDeluxe and associated control panel are shown in Fig. 1.NOTE 4Of the lettered (A-G) p
31、ush buttons on the Mark V Deluxe,only the D push button is applicable to this test method.7.1.2 The Emcee Model 1140 Micro-Separometer Mark Xand associated control panel are shown in Fig. 2. Table 1 liststhe manual and audio operating characteristics of the instru-ment.4The sole source of supply of
32、the apparatus (Model 1140 Micro-Separometer,Mark V Deluxe and Mark X) known to the committee at this time is EMCEEElectronics, Inc., 520 CypressAve., Venice, FL 34285 www.emcee-.If you are aware of alternative suppliers, please provide this information to ASTMInternational Headquarters. Your comment
33、s will receive careful consideration at ameeting of the responsible technical committee,1which you may attend.5The Model 1140 Micro-Separometers Mark III and Mark V Standard versionsmay also be used, but they are no longer supported by the manufacturer. Foroperating procedures using these instrument
34、s, the user is referred to Test MethodD 394887.6Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: D02-1647.D7261082NOTE 5Of the lettered push buttons that select the test mode, only theDIESEL push button is applicable to this test
35、 method.7.1.3 Both the Mark V Deluxe and Mark X Micro-Separometers have the emulsifier located on the right side ofthe raised panel and the syringe drive mechanism on the leftside. The control panel containing the operating controls (pushbuttons) is mounted on the fixed panel in the left side of the
36、case. A circuit breaker located on the control panel providesprotection for the ac power circuit. The turbidimeter is locatedunder the main control panel and consists of a well in which thesample vial is placed, a light source, and a photocell.7.2 Beaker, Catch Pan, or Plastic Container(Suppliedwith
37、 each Micro-Separometer) used to receive the waste fuelduring the coalescence period of the test.7.3 PipetAn automatic 50-L hand pipet (supplied witheach Micro-Separometer) designed to accept a disposableplastic tip.8. Reagents and Materials8.1 Aerosol OT, (AOT), solid (100 % dry) bis-2-ethylhexylso
38、dium sulfosuccinate.FIG. 1 Micro-Separometer Mark V Deluxe and Associated Control PanelFIG. 2 Micro-Separometer Mark X and Control PanelTABLE 1 Manual and Audio Operating Characteristics of the Emcee Model 1140 Micro-Separometer Instrument forMode D/Diesel OperationAvailable Test Mode(s) Function Ma
39、rk V Deluxe Mark XTest Mode - Select Mode DDepress D push button Diesel push buttonSyringe Drive Not required Not requiredSpeed Selection Not required Not requiredClean CycleDepress START push button CLEAN 1CLEAN 2Initiate Automatic Test SequenceDepress START push button RUN push buttonCancel Automa
40、tic SequenceDepress RESET push button RESET push button1st Meter Read1st Meter Adjust Depress ARROW push buttons Not required2nd Meter Read2nd Meter Adjust Depress ARROW push buttons Not requiredCollect Sample Short Tone and C/S Short Tone and C/SAnnunciator Lamp Illuminates Annunciator Lamp Illumin
41、ates3rd Meter ReadRecord Measurement Pulsed Tone Sounds5sinto3rdMeterRead Steady toneD72610838.2 Dispersing AgentToluene solution (WarningFlammable. Vapor harmful.) containing 1 mg of Aerosol OTper milliliter of toluene.8.3 Expendable Materials needed to perform the test areshown in Fig. 3 and consi
42、st of the following:78.3.1 Syringe Plug, (A)A plastic plug used to stopper thesyringe during the clean and emulsion cycles.8.3.2 Syringe, (Barrel (B) and Plunger (C)A disposable50 mL plastic syringe.8.3.3 Vials, (D), 25-mm outside diameter vial premarked forproper alignment in the turbidimeter well.
43、8.3.4 DCell8Coalescer, (E) an expendable, pre-calibratedaluminum coalescer cell with a tapered end to fit the syringe. Itis labeled in a white background with black lettering:DCELLt, DIESEL FUEL, D 72618.3.4.1 In order for a coalescer to be acceptable for this testmethod, it shall have been manufact
44、ured using 2-grades offiberglass and have passed factory calibration tests for air flowand leakage.8.3.5 Disposable Plastic Pipet Tip (F)Used with an auto-matic 50-L hand pipet (Fig. 3, G).8.3.6 Container (H)A clean container of double-distilledwater (8.7).8.4 Reference Fluid BaseA surfactant-free,
45、clean, distil-late diesel fuel which is used to verify proper operation and isprepared in the manner described in Annex A1 (see 3.2.2).(WarningFlammable. Vapor harmful.)8.5 Reference Fluid(WarningFlammable. Vapor harm-ful.) A fluid used for checking the operational performance ofthe Micro-Separomete
46、r instrument), consisting of increasingconcentrations (0 to 1.6 mL/L) of dispersing agent added to thereference fluid base. The DSEP ratings for this range ofconcentrations appear in Table 2. The reference fluids areprepared and tested as described in Sections 12 and 13.8.6 Toluene, ACS reagent grad
47、e. (WarningFlammable.Vapor harmful.)8.7 Water, clean, double-distilled and surfactant-free:D 1193 Type IV reagent water, re-distilled. In practice, re-distillation of commercial distilled water has proven to besatisfactory.8.7.1 Use of water other than double-distilled water (such astap water) will
48、render test results invalid.9. Hazards9.1 The primary hazard in this test method is the flamma-bility of the fuels that are tested. Take suitable precautions toavoid sparks, flames or sources of ignition.9.2 Minimize worker exposure to breathing fuel vapors.10. Preparation of Apparatus10.1 Locate th
49、e instrument on a clean workbench in an areawhere the temperature is between 18 and 29C and does notvary more than 63C.10.2 Open the case, and raise the right panel until com-pletely vertical and locked in place.10.2.1 If ac power is available, connect the power cord.NOTE 6The Micro-Separometer can be purchased with or without aninternal battery pack.10.2.2 If the internal battery power is used, ensure that thebatteries are charged sufficiently to perform the desired numberof tests.NOTE 7Low battery power on the Mark V Del
