1、Designation: D7321 18aStandard Test Method forParticulate Contamination of Biodiesel B100 Blend StockBiodiesel Esters and Biodiesel Blends by LaboratoryFiltration1This standard is issued under the fixed designation D7321; the number immediately following the designation indicates the year oforiginal
2、 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.1. Scope*1.1 This test method covers the determination of the mass ofparticulat
3、e contamination in B100 biodiesel in accordance withSpecification D6751 and BXX blends that are prepared againstall No. 1 and No. 2 grade fuels allowed within SpecificationsD396 and D975.NOTE 1Middle distillate fuels with flash points less than 38 C havebeen ignited by discharges of static electrici
4、ty when the fuels have beenfiltered through inadequately bonded or grounded glass fiber filtersystems. See Guide D4865 for a more detailed discussion of staticelectricity formation and discharge.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are includ
5、ed in thisstandard.1.3 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, health, and environmental practices and deter-mine the applicability of regulatory limit
6、ations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization
7、TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D396 Specification for Fuel OilsD975 Specification for Diesel Fuel OilsD1193 Specification for Reagent WaterD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4865 Guide for Generation and Dissip
8、ation of Static Elec-tricity in Petroleum Fuel SystemsD6751 Specification for Biodiesel Fuel Blend Stock (B100)for Middle Distillate Fuels3. Terminology3.1 Definitions:3.1.1 biodiesel, nfuel comprised of mono-alkyl esters oflong chain fatty acids derived from vegetable oils or animalfats, designated
9、 B100.3.1.2 biodiesel blend, BXX, na fuel composed of biodieselblendstock with hydrocarbon-based diesel fuel.3.1.3 bond, vto connect two parts of a system electricallyby means of a conductive wire to eliminate voltage differences.3.2 Definitions of Terms Specific to This Standard:3.2.1 filtered flus
10、hing fluids, nany of three solvents,methanol, propan-2-ol (isopropanol), or 2,2,4-trimethylpentane, filtered through a nominal 0.45 m filter.3.2.2 glass fiber filter, nglass fiber filter used in this testmethod.4. Summary of Test Method4.1 B100 Biodiesel Blend Stock Filtration:4.1.1 Ameasured volume
11、 of 400 mL to 450 mL of biodieselester (B100) is vacuum filtered through one 0.7 m glass fiberfilter. If upon visual inspection particulate contamination isobserved, this may result in a high filtration time. In such cases,when the contamination is high or of a nature that induces slowfiltration rat
12、es, two or more filtrations using a fresh filter eachtime may be required to complete filtration in a reasonabletime.4.1.2 After the filtration has been completed, the filter iswashed with solvent, dried, and weighed. The particulatecontamination level is determined by the mass gained by theglass fi
13、ber filter, and is reported in units of grams per cubicmetre or its equivalent in milligrams per litre.4.2 BXX Biodiesel Blend Filtration:1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommitt
14、ee D02.14 on Stability, Cleanliness and Compatibility of Liquid Fuels.Current edition approved Oct. 1, 2018. Published October 2018. Originallyapproved in 2008. Last previous edition approved in 2018 as D7321 18. DOI:10.1520/D7321-18A.2For referenced ASTM standards, visit the ASTM website, www.astm.
15、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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C
16、700, West 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
17、World Trade Organization Technical Barriers to Trade (TBT) Committee.14.2.1 Ameasured volume of 800 mL to 900 mL of biodieselblend (BXX) is vacuum filtered through one 0.7 m glass fiberfilter. If upon visual inspection particulate contamination isobserved, this may result in a high filtration time.
18、In such cases,when the contamination is high or of a nature that induces slowfiltration rates, two or more filtrations using a fresh filter eachtime may be required to complete filtration in a reasonabletime.4.2.2 After the filtration has been completed, the filter iswashed with solvent, dried, and
19、weighed. The particulatecontamination level is determined by the mass gained from theglass fiber filter, and is reported in units of grams per cubicmetre or its equivalent in milligrams per litre.5. Significance and Use5.1 The mass of particulates present in a fuel is a significantfactor, along with
20、 the size and nature of the individualparticles, in the rapidity with which fuel system filters andother small orifices in fuel systems can become plugged. Thistest method provides a means of assessing the mass ofparticulates present in a fuel sample.5.2 The test method can be used in specifications
21、 andpurchase documents as a means of controlling particulatecontamination levels in the fuels purchased.6. Apparatus6.1 Filtration SystemArrange the following componentsas shown in Fig. 1.6.1.1 Funnel and Funnel Base, with filter support for a47 mm diameter glass fiber, and locking ring or spring ac
22、tionclip.6.1.2 Ground/Bond Wire, 0.912 mm to 2.59 mm (No. 10through No. 19) bare stranded flexible, stainless steel, orcopper installed in the flasks and grounded as shown in Fig. 1.NOTE 2The electrical bonding apparatus shown in Fig. 1 or othersuitable means of electrical grounding that ensure safe
23、 operation of thefiltration apparatus and flask can be used. If the filtrate is to besubsequently tested for stability, it is advisable not to use copper sincecopper ions catalyze gum formation during the stability test.6.1.3 Receiving Flask, 1.5 L or larger borosilicate glassvacuum filter flask, in
24、to which the filtration apparatus fits,equipped with a sidearm to connect to the safety flask.6.1.4 Safety Flask, 1.5 L or larger borosilicate glass vacuumfilter flask equipped with a sidearm to connect the vacuumsystem. A fuel and solvent resistance rubber hose throughwhich the grounding wire passe
25、s shall connect the sidearm ofthe receiving flask to the tube passing through the rubberstopper in the top of the safety flask.6.1.5 Vacuum System, either a water aspirated or a mechani-cal vacuum pump may be used if capable of producing avacuum of 1 kPa to 100 kPa below atmospheric pressure whenmea
26、sured at the receiving flask.6.2 Other Apparatus:6.2.1 Air Ionizer, if used for the balance case.Air ionizers ifused should be replaced annually.NOTE 3When using a solid-pan balance, the air ionizer may beomitted provided that, when weighing a glass fiber filter, it is placed on thepan so that no pa
27、rt protrudes over the edge of the pan.6.2.2 Analytical Balance, single- or double-pan, with theprecision standard deviation of 0.07 mg or less.6.2.3 Crucible Tongs, for handling clean sample containerlids.6.2.4 Drying Oven, naturally convected (without fan-assisted air circulation), controlling to 9
28、0 C 6 5 C.6.2.5 Flushing Fluid Dispenser, an apparatus for dispensingflushing fluid through a nominal 0.45 m filter.6.2.6 Forceps, approximately 12 cm long, flat-bladed, withnon-serrated, non-pointed tips.6.2.7 Graduated Cylinders, to contain at least 1 L of fluidand marked at 10 mL intervals. For s
29、amples that filter slowly,100 mL graduated cylinders may be required.6.2.8 Petri Dishes, approximately 12.5 cm in diameter, withremovable glass supports for glass fiber filters.NOTE 4Small watch glasses, approximately 5 cm to 7 cm in diameter,have also been found suitable to support the glass fiber
30、filter.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 Commit-tee on Analytical Reagents of the American Chemical Society,where such specifications
31、 are available.3Other 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 Purity of WaterUnless otherwise indicated, referencesto water mean reagent water as defined by Types I, II and
32、III ofSpecification D1193.7.3 Flushing Fluids:7.3.1 Methanol, (Warning Flammable).7.3.2 2,2,4-trimethylpentane (isooctane), (WarningFlammable).3Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted
33、by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.FIG. 1 Schematic of Filtration SystemD7321 18a27.3.3 propan-2-ol (2-propan
34、ol; isopropyl alcohol),(WarningFlammable).7.4 Liquid or Powder Detergent, water-soluble, for cleaningglassware.7.5 Glass Fiber Filter, plain, with a diameter of 47 mm anda nominal pore size of 0.7 m.7.6 Protective Cover, polyethylene film or clean aluminumfoil.8. Sampling8.1 Sampling for Procedure f
35、or Biodiesel Blend Stock(B100):8.1.1 The sample container should be 500 mL (615 mL) involume and have a screw-on cap with an inert liner. Glasscontainers are preferred to facilitate a visual inspection of thecontents and the container before and after filling. Glasscontainers also allow for visual i
36、nspection of the container,after the sample is emptied, to confirm complete rinsing of thecontainer. Epoxy-lined sample cans, polytetrafluoroethylene(PTFE) bottles, and high density linear polyethylene bottleshave also been found suitable as sample containers, but theyare less desirable since visual
37、 inspection of the interior of thecontainer is more difficult.8.1.1.1 It is imperative that the entire contents of the samplecontainer are filtered during the B100 filtration. This includesnot only all of the fuel but also all rinsings of the interior of thecontainer with flushing fluid. Because of
38、this, take care toprotect the sample from any external contamination.8.1.2 If it is not possible to sample in a 500 mLbottle, or thesample has already been received in a 1 L bottle, follow8.1.2.1.8.1.2.1 Vigorously shake the sample for 1 min, and transfer400 mL to 450 mL (615 mL) to a clean fresh 50
39、0 mL bottle. Ifa clean fresh 500 mL bottle is not available, use a clean fresh1 L bottle.8.1.3 Precautions to avoid sample contamination shall in-clude selection of an appropriate sampling point. Samplesshould preferentially be obtained dynamically from a samplingloop in a distribution line, or from
40、 the flushing line of a fieldsampling kit. Ensure that the line to be sampled is flushed withfuel before taking the sample.8.1.3.1 Where it is desirable or only possible to obtainsamples from static storage, follow the procedures given inPractice D4057 or equivalent, taking precautions for cleanli-n
41、ess of all equipment used. Ensure that the sample has notpassed through intermediate containers prior to placement inthe prepared container.NOTE 5Samples obtained from static storage may give results that arenot representative of the bulk contents of the tank because of particulatematter settling. W
42、here possible, the contents of the tank should becirculated or agitated before sampling, or the sampling should beperformed shortly after a tank has been filled.8.1.4 Visually inspect the sample container before collect-ing the samples to verify that there are no visible particlespresent inside the
43、container. Collect 800 mL to 900 mL(615 mL), in a 1 L sample bottle or 400 mL to 500 mL(615 mL) in a 500 mL (615 mL) sample bottle and ensurethat there is an ullage (vapor space) of at least 10 % of thecontainer volume to allow for liquid expansion. Protect the fuelsample from prolonged exposure to
44、light by wrapping thecontainer in aluminum foil or storing it in the dark to reduce thepossibility of particulate formation by light-promoted reac-tions. Do not transfer the fuel sample from its original samplecontainer into an intermediate storage container. If the originalsample container is damag
45、ed or leaking, then a new samplemust be obtained.8.1.5 Analyze fuel samples as soon as possible after sam-pling. When a fuel cannot be analyzed within one day, it shouldbe blanketed with an inert gas such as oxygen-free nitrogen,argon, or helium. Store at a temperature no higher than 10 C;samples wi
46、th cloud points above 10 C may be stored at roomtemperature.8.2 Sampling for Procedure for Biodiesel Blends (BXX):8.2.1 The sample container for BXX shall be 1 L (615 mL)in volume and have a screw-on cap with an inert liner. Glasscontainers are preferred to facilitate a visual inspection of theconte
47、nts and the container before and after filling. Glasscontainers also allow for visual inspection of the container,after the sample is emptied, to confirm complete rinsing of thecontainer. Epoxy-lined sample cans, polytetrafluoroethylene(PTFE) bottles, and high density linear polyethylene bottleshave
48、 also been found suitable as sample containers, but theseare less desirable since visual inspection of the interior of thecontainer is more difficult.8.2.1.1 It is important to note that the entire contents of thesample container are filtered during the BXX filtration. Thisincludes not only all of t
49、he fuel but also all rinsings of theinterior of the container with flushing fluid. Because of this,take care to protect the sample from any external contamina-tion.The expectation is that the volume in the 1 Lsample bottlewill be 800 mL to 900 mL, allowing for 10 % ullage.8.2.2 Follow 8.1.3 8.1.5.9. Preparation of Apparatus and Sample Containers9.1 Clean all components of the filtration apparatus asdescribed in 9.1.1 9.1.4.9.1.1 Remove any labels, tags, and so forth.9.1.2 Rinse apparatus thoroughly with propan-2-ol that hasbeen filtered through a 0.45
