1、Designation: D5771 15D5771 17Designation: IP 44409Standard Test Method forCloud Point of Petroleum Products and Liquid Fuels(Optical Detection Stepped Cooling Method)1This standard is issued under the fixed designation D5771; the number immediately following the designation indicates the year oforig
2、inal 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.INTRODUCTIONThis test method describes an alternative procedure for the det
3、ermination of cloud point ofpetroleum products Test Method D2500/IP 219 using an automatic apparatus. The temperature resultsfrom this test method have been found to be equivalent to Test Method D2500/IP 219. Whenspecification requires Test Method D2500/IP 219, do not substitute this test method or
4、any othermethod without obtaining comparative data and agreement from the specifier.1. Scope*1.1 This test method covers the description of the determination of the cloud point of petroleum products and biodiesel fuelsthat are transparent in layers 40 mm in thickness, by an automatic instrument usin
5、g an optical device.1.2 This test method covers the range of temperatures from 60 C to +49 C with temperature resolution of 0.1 C, however,the range of temperatures included in the 1997 interlaboratory cooperative test program only covered the temperature range of56 C to +34 C.1.3 The values stated
6、in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and
7、health practices and determine the applicability of regulatorylimitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Gu
8、ides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D2500 Test Method for Cloud Point of Petroleum Products and Liquid FuelsD4057 Practice for Manual Sampling of Petroleum and Petroleum ProductsD4177 Pr
9、actice for Automatic Sampling of Petroleum and Petroleum ProductsD6708 Practice for Statistical Assessment and Improvement of Expected Agreement Between Two Test Methods that Purportto Measure the Same Property of a Material2.2 Energy Institute Standard:3IP 219 Test Method for Cloud Point of Petrole
10、um Products32.3 Other Standard:4IEC 751 Industrial Platinum Resistance Thermometer Sensors1 This test method is under the jurisdiction ofASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of SubcommitteeD02.07 on Flow Properties.Current edition ap
11、proved April 1, 2015May 1, 2017. Published April 2015May 2017. Originally approved in 1995. Last previous edition approved in 20122015 asD5771 12.D5771 15. DOI: 10.1520/D5771-15.10.1520/D5771-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at s
12、erviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from Energy Institute, 61 New Cavendish St., London, WIG 7AR, U.K., http:/www.energyinst.org.uk.4 Available from International Electrotechnical Commission
13、 (IEC), 3 rue de Varemb, Case postale 131, CH-1211, Geneva 20, Switzerland, http:/www.iec.ch.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possi
14、ble to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopy
15、right ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13. Terminology3.1 Definitions:3.1.1 biodiesel, nfuel comprised of mono-alkyl esters of long chain long-chain fatty acids derived from vegetable oils oranimal fats, designated B 100.3.1.1.1 D
16、iscussionBiodiesel is typically produced by a reaction of vegetable oil or animal fat with an alcohol such as methanol or ethanol in thepresence of a catalyst to yield mono-esters and glycerin. The fuel typically may contain up to 14 different types of fatty acids thatare chemically transformed into
17、 fatty acid methyl esters (FAME).3.1.2 biodiesel blend, na blend of biodiesel fuel with petroleum-based diesel fuel designated BXX, where XX is the volume% of biodiesel.3.1.3 cloud point, n in petroleum products and biodiesel fuels, the temperature of a liquid specimen when the smallestobservable cl
18、uster of hydrocarbonwax crystals first occurs upon cooling under prescribed conditions.3.1.3.1 DiscussionThe cloud point occurs when the temperature of the specimen is low enough to cause hydrocarbonwax crystals to precipitate. Ina homogeneous liquid, the cloud is always noted first at the location
19、in the specimen where the specimen temperature is the lowest.The cloud point is the temperature at which the crystals first occur, regardless of their location in the specimen, and not afterextensive crystallization has taken place. The hydrocarbonwax crystals that precipitate at lower temperatures
20、are typically, but notexcluded to, straight chain hydrocarbons commonly called “wax crystals.”straight-chain hydrocarbons and lipids.3.1.3.2 DiscussionThe purpose of the cloud point method is to detect the presence of the wax crystals in the specimen; however, trace amounts ofwater and inorganic com
21、pounds may be present. The intent of the cloud point method is to capture the temperature at which theliquids in the specimen begin to change from a single liquid phase to a two-phase system containing solid and liquid. It is not theintent of this test method to monitor the phase transition of the t
22、race components, such as water.3.2 Definitions of Terms Specific to This Standard:3.2.1 automatic cloud point, nthe temperature of a specimen when the appearance of the cloud is determined under theconditions of this test method.3.2.1.1 DiscussionThe cloud point in this test method is determined by
23、an automatic instrument using an optical device for detection of the crystalformation. The apparatus and the conditions are different from those established for Test Method D2500, although, according tointerlaboratory examination the results have been determined to be equivalent to Test Method D2500
24、.3.2.2 optical detection stepped cooling method, nin cloud point test methods, test procedure using prescribed cooling rate,specimen receptacle, and optical system for detection of crystal formation.3.2.2.1 DiscussionThe prescribed cooling rate is described in 4.1;, the specimen receptacle is descri
25、bed in Section 6, and the optical system for thedetection of crystal formation is described in Section 6.3.2.3 D2500/IP 219 equivalent cloud point, nthe temperature of a specimen, in integers, calculated by rounding the resultsof this test method to the next lower integer.3.2.3.1 DiscussionThis test
26、 method produces results with 0.1 C resolution. Should the user wish to provide results with a similar format to TestMethod D2500, then this calculation can be performed. Some apparatus can perform this calculation automatically.D5771 1724. Summary of Test Method4.1 After insertion of the prescribed
27、 test jar (6.3) containing the specimen into the apparatus, and the initiation of the program,the specimen is cooled incrementally according to the cooling profile listed in Table 1. The specimen is continuously monitoredby a reflective optical system (6.1 and Fig. 1) for the formation of a crystall
28、ine structure. When the crystallization of the wax inthe specimen is detected by the optical system, the temperature is recorded to within 0.1 C resolution. The specimen is then heatedto facilitate the start of the next test.5. Significance and Use5.1 For petroleum products and biodiesel fuels, the
29、cloud point is an index of the lowest temperature of their utility for certainapplications. Wax crystals of sufficient quantity can plug filters used in some fuel systems.5.2 Petroleum blending operations require precise measurement of the cloud point.5.3 This test method can determine the temperatu
30、re of the test specimen at which wax crystals have formed sufficiently to beobserved as a cloud with a resolution of 0.1C.0.1 C.5.4 This test method provides results that, when rounded to the next lower integer, are equivalent to Test Method D2500. Referto 12.2.5.5 This test method is more precise t
31、han Test Method D2500.NOTE 1According to interlaboratory examination, the reproducibility of this test method has been found to be more precise than Test Method D2500.6. Apparatus6.1 Optical Cloud Point Apparatus5The automated cloud point apparatus (see Fig. 2) described in this test method consists
32、of a microprocessor controller that is capable of controlling one or more independent test cells. The apparatus shall includeprovisions for independently controlling the temperature of each cell according to the specified cooling profile, continuously5 The sole source of supply of the ISL Model CPP9
33、7-6 and CPP97-2 and CPP-5Gs known to the committee at this time is ISL SA, BP 40, 14790 Verson, France. If youare aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at a meeting ofthe responsible techni
34、cal committee,1 which you may attend.TABLE 1 Jacket and Specimen Cooling TemperaturesSpecimen Temperature, C Jacket Temperature, CST + 10 0 0.5+ 10 $ ST 7 17.2 0.57 $ ST 24 34.2 0.524 $ ST 41 51.2 0.541 $ ST 58 68.2 0.558 $ ST 75 85.2 0.5D5771 173monitoring the specimen temperature, detecting the ap
35、pearance of the cloud point at the bottom of the test jar without removingit from the jacket, and displaying the 0.1 C or 1.0 C result (see Fig. 1 and Fig. 3).6.2 Temperature Probe, IEC 751 Class A: T = 6(0.15 + 0.002|T|), capable of measurement from 50 C to +80 C. Thetemperature probe shall be in c
36、ontact with the bottom of the test jar.6.3 Test Jar, clear cylindrical glass, mirrored flat bottom, 34 mm 6 0.5 mm outside diameter, 1.4 mm 6 0.15 mm wallthickness, 120 mm 6 0.5 mm height, thickness of the bottom 2.0 mm 6 0.5 mm, marked with a line to indicate the sample height54 mm 6 0.5 mm above t
37、he inside bottom.6.4 Jacket, brass, cylindrical, flat bottom, 113 mm 6 0.2 mm in depth, 45 mm 6 0.1 mm inside diameter. It must be cooledaccording to the cooling profile specified.6.5 Cooling System, either an external system equipped with a circulating pump and capable of maintaining a temperature
38、atleast 10 C below the last required jacket temperature level (see Table 1 and Fig. 3), or an internal system capable of maintainingthe required jacket temperatures (see Table 1 and Fig. 3).6.6 Cork Disk, 6 mm 6 0.2 mm thick, to fit loosely inside the jacket. Felt may be used but special attention m
39、ust be given tothe potential for moisture in the felt disk. The felt must be dried before each test.6.7 Cork Ring, to fit snugly around the outside of the test jar and loosely inside the sample cell. Its purpose is to prevent thetest jar from touching the jacket.7. Reagents and Materials7.1 Cleaning
40、 Solvents, suitable for cleaning and drying the test cell, such as petroleum naphtha and hexane.7.2 Methyl Alcohol, Anhydrous, for use as cooling medium in circulating bath cooling system, when used.7.3 Sodium SulfateA reagent grade of anhydrous sodium sulfate should be used when required. (WarningF
41、lammable.Liquid causes eye burns. Vapor harmful. May be fatal or cause blindness if swallowed or inhaled.)7.4 Lint-free filter paper may be used as a drying medium.8. Sampling8.1 Obtain a sample in accordance with PracticesPractice D4057 or by D4177.8.2 Samples of very viscous materials may be warme
42、d until they are reasonably fluid before they are sampled. However, nosample should be heated more than is absolutely necessary.8.3 The sample shall not be heated above 70 C. If the sample is heated above 70 C, allow the sample to cool below 70 Cbefore filtering or inserting into the apparatus.8.4 W
43、hen moisture is present in the sample, remove the moisture by a method,method such as filtration through dry, lint-freefilter paper, until the oil is perfectly clear, but make such filtration at a temperature at least 14 C above the expected cloud point.FIG. 1 Test Jar and Detection SystemD5771 174N
44、OTE 2Awax cloud or haze is always noted at the bottom of the test jar where the temperature is lowest.Aslight haze throughout the entire specimen,which slowly becomes more apparent as the temperature is lowered, is usually due to water in the specimen. Generally this water haze will not interferewit
45、h the determination of the wax cloud point. In most cases of interference, filtration through dry lint-free filter papers such as described in 11.2 issufficient.FIG. 2 Automated Cloud Point ApparatusD5771 1758.5 For diesel fuels, if the haze is very dense, a fresh portion of sample must be dried by
46、shaking 100 mL with 5 g of anhydroussodium sulfate for at least 5 min and then filtering through dry lint-free filter paper. Given sufficient contact time, this procedurewill remove or sufficiently reduce the water haze so that the wax cloud can be readily discerned. Drying and filtering should alwa
47、ysbe done at a temperature at least 14 C above the approximate cloud point, but otherwise not in excess of 49 C.9. Preparation of Apparatus9.1 Prepare the instrument for operation in accordance with the manufacturers instructions.9.2 Clean and dry the test head and test jar using suitable solvents a
48、s prescribed by the manufacturer.9.3 Adjust the set point of the cooling system, when necessary, to the appropriate temperature to cool the jacket to the requiredtemperature (see Table 1).10. Calibration and Standardization10.1 Ensure that all of the manufacturers instructions for calibrating, check
49、ing, and operating the apparatus are followed.10.1.1 A test head simulator with a known resistance is used to calibrate the equipment. Follow the manufacturers calibrationinstructions.NOTE 3A test head simulator may be obtained from the apparatus supplier which can assist in verification of temperature measurement.10.2 A sample with a mutually agreed upon cloud point such as a sample from a interlaboratory test program can be used toverify performance of the apparatus.11. Procedure11.1 Set th
