1、Designation: D7501 12Standard Test Method forDetermination of Fuel Filter Blocking Potential of Biodiesel(B100) Blend Stock by Cold Soak Filtration Test (CSFT)1This standard is issued under the fixed designation D7501; 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.1. Scope*1.1 This test method covers the determination by filtrationtime after col
3、d soak of the suitability for a biodiesel (B100)blend stock that meets all other requirements of SpecificationD6751 and has a cloud point below 20C (68F) to provideadequate low temperature operability performance to at leastthe cloud point of the finished blend.1.2 The formal precision of this test
4、method is included in13.1 on Precision.1.3 The values stated in SI units are to be regarded asstandard. No other units 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
5、user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD6217 Test Method for Particulate Contam
6、ination inMiddle Distillate Fuels by Laboratory FiltrationD6300 Practice for Determination of Precision and BiasData for Use in Test Methods for Petroleum Products andLubricantsD6751 Specification for Biodiesel Fuel Blend Stock (B100)for Middle Distillate Fuels3. Terminology3.1 Definitions:3.1.1 bio
7、diesel, nfuel comprised of mono-alkyl esters oflong chain fatty acids derived from vegetable oils or animalfats, designated as B100.3.1.2 bond, vto connect two parts of a system electricallyby means of a conductive wire to eliminate voltage differences.3.1.3 BXX blend, nfuel blend consisting of up t
8、o 20volume percent biodiesel designated as up to B20 conformingto the requirements of Specification D6751 with the remainderbeing a light middle or middle distillate grade diesel fuel andmeeting the requirements of this test method.3.1.3.1 DiscussionThe abbreviation BXX represents aspecific blend co
9、ncentration in the range B2 to B20, where XXis the percent volume of biodiesel in the fuel blend.3.1.4 ground, vto connect electrically with earth.3.2 Definitions of Terms Specific to This Standard:3.2.1 air chamber, nunit to control temperature of samplefor cooling with maximum 0.5C variation from
10、set point. Theunit shall use a microprocessor temperature controller withdigital set point and readout.Afood-grade refrigerator does notprovide adequate temperature stability for this test method.3.2.2 minor component, nmaterial present in B100, typi-cally at concentrations well below 1% by mass.3.2
11、.3 thermal history, nrange of temperatures that a batchor sample of B100 has experienced which can result inseparation or precipitation of minor components.3.2.3.1 DiscussionCooling some biodiesel fuels can resultin precipitation or separation of minor components that havelimited solubility in B100.
12、 Heating these biodiesel fuels above40C is believed to redissolve most of these minor componentsand thus erase the thermal history of the sample.3.3 Abbreviations:3.3.1 CSFTCold Soak Filtration Test1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants
13、and is the direct responsibility of SubcommitteeD02.14 on Stability and Cleanliness of Liquid Fuels.Current edition approved April 15, 2012. Published July 2012. Originallyapproved in 2009. Last previous edition approved in 2009 as D750109b. DOI:10.1520/D7501-12.2For referenced ASTM standards, visit
14、 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.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 1
15、00 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Summary of Test Method4.1 In this test method, 300 mL of biodiesel (B100) is storedat 4.5 6 0.5C (40 6 1F) for 16 h, allowed to warm to 25 61C (77 6 2F), and vacuum filtered through a single 0.7 mglass fiber filter
16、 at controlled vacuum levels of 7085 kPa(2125 in. of Hg).4.2 The filtration time is reported in seconds.5. Significance and Use5.1 Some substances that are soluble or appear to be solublein biodiesel (B100) at room temperature will, upon cooling totemperatures above the cloud point or standing at ro
17、omtemperature for extended periods, come out of solution. Thisphenomenon has been observed in both B100 and BXX blends.These substances can cause filter plugging. This methodprovides an accelerated means of assessing the presence ofthese substances in B100 and their propensity to plug filters.5.1.1
18、B100 biodiesel fuels that give short filtration times areexpected to give satisfactory operation of BXX blends at leastdown to the cloud point of the biodiesel blends.5.2 The test method can be used in specifications as a meansof controlling levels of minor filter plugging components inbiodiesel and
19、 biodiesel blends.6. Apparatus6.1 Filtration SystemArrange the following componentsas shown in Fig. 1.6.1.1 Funnel and Funnel Base, with a stainless steel filtersupport for a 47-mm diameter glass fiber filter, and locking ringor spring action clip, capable of receiving 300 mL.NOTE 1Sintered glass su
20、pports were found to give much higherfiltration times during initial studies and are not recommended to be used.6.1.2 Ground/Bond Wire, 0.912-2.59-mm (No. 10 throughNo. 19) bare stranded flexible, stainless steel or copperinstalled in the flasks and grounded as shown in Fig. 1.6.1.3 Electrical Bondi
21、ng Apparatus, as described in TestMethod D6217 or by using other suitable means of electricalgrounding that ensure safe operation of the filtration apparatusand flask. This may not be necessary in filtering biodiesel B100because of the higher electrical conductivity.6.1.4 Receiving Flask, 1-L borosi
22、licate glass vacuum filterflask, into which the filtration apparatus fits, and equipped witha sidearm to connect to the safety flask.6.1.5 Safety Flask, 1-L borosilicate glass vacuum filter flaskequipped with a sidearm to connect the vacuum system. A fueland solvent resistant rubber hose, through wh
23、ich the groundingwire is connected to the sidearm of the receiving flask to thetube, passes through the rubber stopper in the top of the safetyflask.6.1.6 Vacuum System, capable of producing a vacuum of70 to 85 kPa (2125 in. of Hg) when measured at the safetyflask. A mechanical vacuum pump may be us
24、ed if it has thiscapability.NOTE 2Water aspirated vacuum will not provide relative vacuumwithin the prescribed range.6.1.7 Chilling Apparatus, either 6.1.7.1 or 6.1.7.2 may beused.6.1.7.1 Circulating Water Bath, capable of sustaining atemperature of 4.5 6 0.5C (40 6 1F).FIG. 1 Schematic of Filtratio
25、n SystemD7501 1226.1.7.2 Air Chamber, capable of sustaining a temperature of4.5 6 0.5C (40 6 1F). The unit shall use microprocessortemperature control and have a digital temperature control/display.6.1.8 Circulating Water Bath, capable of sustaining a tem-perature of 25 6 0.5C (77 6 1F).6.1.9 Whatma
26、n Glass Fiber Filters (GF/F),3plain, 47-mmdiameter, nominal pore size 0.7-m. Acid treated low metalTCLP filters are not suitable for this purpose.6.2 Other Apparatus:6.2.1 Forceps, approximately 12-cm long, flat-bladed, withnon-serrated, non-pointed tips.6.2.2 Graduated Cylinders, to contain at leas
27、t 0.5 L of fluidand marked at 10-mL intervals. Samples that filter slowly mayrequire 100-mL graduated cylinders.6.2.3 Petri Dishes, approximately 12.5 cm in diameter, withremovable glass supports for glass fiber filters.6.2.3.1 Small Watch Glasses, approximately 5 to 7 cm indiameter, have been found
28、 suitable to support the glass fiberfilters.NOTE 3B100 will dissolve some plastics. This can cause the filters toadhere to the plastic.6.2.4 Protective Cover, polyethylene film or clean alumi-num foil.6.2.5 Timer, capable of displaying elapsed times of at least900 s to the nearest 0.1 s.6.2.6 Thermo
29、meter or RTD Sensor, for measuring sampletemperature, should be capable of measurement 60.5C(61F).7. Reagents and Materials7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the C
30、ommit-tee on Analytical Reagents of the American Chemical Society,where such specifications are available. Other grades may beused, provided it is first ascertained that the reagent is ofsufficient purity to permit its use without lessening the accu-racy of the determination.7.2 Flushing FluidsFlush
31、ing fluids are not required forthe test as the filter is not weighed. However, heptane orisooctane may be used to wash the apparatus after filtration toremove any residue.7.2.1 Heptane,(WarningFlammable.)7.2.2 2,2,4-trimethylpentane (isooctane),(WarningFlammable.)7.3 Liquid or Powder Detergent, wate
32、r-soluble, for cleaningglassware.8. Sampling8.1 A separate representative sample shall be collected forthis test method. Samples may preferentially be obtaineddynamically from a sampling loop in a distribution line or fromthe flushing line of a field sampling kit. Ensure that the line tobe sampled i
33、s flushed with fuel before collecting the sample.Alternatively, circulate or agitate the contents of the tank inorder to collect a representative sample that includes anyprecipitates that might have settled in the tank. One option is tosample the tank immediately after filling, before the contentsha
34、ve time to settle.8.1.1 Where it is necessary to obtain samples from staticstorage using a sampling container or intermediate containers,follow the procedures given in Practice D4057 or equivalent,taking precautions for cleanliness of all equipment used. Thisis interpreted to mean a representative s
35、ample in accordancewith Practice D4057, and refers to an “all-levels” sample.(WarningSamples obtained from static storage can giveresults which are not representative of the bulk contents of thetank because of particulate matter settling.)8.2 Precautionsto avoid sample contamination include:8.2.1 Se
36、lection of an appropriate sampling point.8.2.2 Use of clean sample containers. Visually inspect thesample container before taking the samples to verify that thereare no visible particles present inside the container.8.2.3 Keeping a clean protective cover over the top of thesample container until the
37、 cap is replaced after filling.8.2.4 If the primary sample container cannot be selectedsuch that it is suitable for this test procedure, the sample shallpass through only a minimum number of intermediate contain-ers prior to placement in the final container.8.2.5 After filling the sample container w
38、ith 300 mL ofsample, protect the fuel sample from prolonged exposure tolight by wrapping the container in aluminum foil or storing itin the dark to reduce the possibility of particulate formation bylight-promoted reactions.8.3 If 300 mL of sample is not received in a 500-mL bottleor the sample has b
39、een received in a container not suitable forthis test, follow the sampling condition procedure in 8.4.8.4 Sample Conditioningfor samples received that mighthave been cooled to temperatures below 20C (68F):8.4.1 Upon receipt of a biodiesel blend stock (B100)sample, the entire sample is to be heated t
40、o 40C (104F) forat least 3 h under an inert atmosphere to erase any thermalhistory and to dissolve any solids that might have precipitatedduring transit. After heating for the required time, allow thesample to sit for 24 h at a temperature no lower than 20C(68F).8.4.2 This sample conditioning step m
41、ay be omitted if thesample was collected from a heated tank at a productionfacility. In this case, proceed directly to 8.5.8.4.3 If there is any doubt about the thermal history of thesample, the sample conditioning step shall be performed.8.5 Analyze fuel samples as soon as possible after sampling.8
42、.6 Shake the sample vigorously for 1 min. If the sample isnot already in a 500-mL bottle suitable for this test procedure,transfer 300 mL to a clean, fresh 500 6 15-mL bottle. If a300-mL sample was received is already in such a bottle,proceed with the test procedure in Section 11.9. Preparation of A
43、pparatus and Sample Containers9.1 Clean all components of the filtration apparatus usingthe reagents described in 7.2 and 7.3.9.1.1 Filtration apparatus shall be clean and dry prior to use.9.1.2 Remove any labels, tags, and so forth.3Whatman filters were used in the ILS. See Section 13.D7501 12310.
44、Preparation of Glass Fiber Filter10.1 Each filtration uses one filter as specified in 6.1.9. Theglass fiber filter used for each individual test may be identifiedby marking the petri dish used to hold and transport the filter.10.2 Clean all glassware used in preparation of glass fiberfilter as descr
45、ibed in 9.1.10.3 Using forceps, place the filter on clean glass supportrods or watch glasses in petri dish.10.4 Place the petri dish, with its lid slightly ajar, in a dryingoven at 90 6 2C (194 6 3.6F) and leave it for 30 min.10.5 Remove the petri dish from the drying oven. Keep thepetri dish cover
46、ajar, such that the filter is protected fromcontamination from the atmosphere.Allow 30 min for the filterto come to equilibrium with room air temperature and humid-ity.10.6 Using clean forceps, place the filter centrally on thefilter support of the filtration apparatus (see Fig. 1). Install thefunne
47、l and secure with locking ring or spring clip.10.7 Protect the funnel opening of the assembled filtrationapparatus with a clean protective cover until ready for use.11. Procedure11.1 Place 300 mL of sample in a 500 mL glass bottle andset in a liquid or air chamber at 4.5 6 0.5C (40 6 1F) for 166 0.2
48、5 h. A refrigerator is not suitable for this procedure.11.2 After the 16-h cold soak at 4.5 6 1.1C (40 6 2F) iscompleted, remove sample from bath and place in a circulatingwater bath with the temperature set to 25 6 0.5C (77 6 1F)according to 11.2.1 or 11.2.2. The sample shall be completelyliquid be
49、fore filtration.11.2.1 If the sample is completely liquid after the 16-h coldsoak, heat the sample at 25 6 0.5C (77 6 1F) for 2 6 0.25h. Otherwise follow 11.2.2.11.2.2 If the sample is solid or contains any solids or hazeafter the 16-h cold soak, heat the sample at 25 6 0.5C (77 61F) for 4 6 0.25 h.11.2.3 Verify that the sample is at 25 6 0.5C (77 6 1F) bydipping without stirring or agitating the sample with an RTDsensor or thermometer.11.3 Filter the samples as quickly as possible upon removalfrom the warming bath onc
