ASTM D5853-2006 Standard Test Method for Pour Point of Crude Oils《原油倾点的标准试验方法》.pdf

1、Designation: D 5853 06Designation: 441/99An American National StandardStandard Test Method forPour Point of Crude Oils1This standard is issued under the fixed designation D 5853; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the

2、year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers two procedures for the deter-mination of the pour point temperatures of crude oils d

3、own to36C. Procedure A provides a measure of the maximum(upper) pour point temperature and is described in 9.1. Proce-dure B provides a measure of the minimum (lower) pour pointtemperature and is described in 9.2.1.2 The use of this test method is limited to use for crudeoils. Pour point temperature

4、s of other petroleum products canbe determined by Test Method D97.1.3 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 i

5、s 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. For specific hazardstatements, see Section 7.2. Referenced Documents2.1 ASTM Standards:2D97 Test Method for Pour Point of Pe

6、troleum ProductsD 130 Test Method for Corrosiveness to Copper fromPetroleum Products by Copper Strip TestD 323 Test Method for Vapor Pressure of Petroleum Prod-ucts (Reid Method)D 4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD 4177 Practice for Automatic Sampling of Petroleum

7、andPetroleum ProductsE1 Specification for ASTM Liquid-in-Glass ThermometersE77 Test Method for Inspection and Verification of Ther-mometers3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 maximum (upper) pour point, nthe pour point ob-tained after the test specimen has been sub

8、jected to a pre-scribed treatment designed to enhance gelation of wax crystalsand solidification of the test specimen.3.1.2 minimum (lower) pour point, nthe pour point ob-tained after the test specimen has been subjected to a pre-scribed treatment designed to delay gelation of wax crystalsand solidi

9、fication of the test specimen.3.1.3 pour point, nthe lowest temperature at which move-ment of the test specimen is observed under the conditions ofthe test.4. Summary of Test Method4.1 After preliminary heating, the test specimen is cooled ata specified rate and examined at intervals of 3C for flowc

10、haracteristics. The lowest temperature at which movement ofthe test specimen is observed is recorded as the pour point.5. Significance and Use5.1 The pour point of a crude oil is an index of the lowesttemperature of handleability for certain applications.5.2 This is the only pour point method specif

11、ically designedfor crude oils.5.3 The maximum and minimum pour point temperaturesprovide a temperature window where a crude oil, depending onits thermal history, might appear in the liquid as well as thesolid state.5.4 The test method can be used to supplement othermeasurements of cold flow behavior

12、. It is especially useful forthe screening of the effect of wax interaction modifiers on theflow behavior of crude oils.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.07 on Flow Properties.Curr

13、ent edition approved July 1, 2006. Published July 2006. Originally approvedin 1995. Last previous edition approved in 2000 as D 585395(2000)e1.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards vo

14、lume 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, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6. Apparatus6.1 Pour Point Test Appar

15、atus Assembly (see Fig. 1):6.1.1 Test Jar, cylindrical, of clear glass, flat bottomed,outside diameter 33.2 to 34.8 mm, and height 115 to 125 mm.The inside diameter of the jar can range from 30.0 to 32.4 mm,within the constraint that the wall thickness shall be no greaterthan 1.6 mm. The jar shall h

16、ave a line to indicate a sampleheight 54 6 3 mm above the inside bottom. The inside of thetest jar (up to the mark) shall be visibly clean and free ofscratches.6.1.2 Thermometers, having ranges shown in the followingtable and conforming to the requirements prescribed in Speci-fication E1for thermome

17、ters:ThermometerThermometer Temperature RangeNumberASTM IPHigh cloud and pour 38 to +50C 5C 1CLow cloud and pour 80 to +20C 6C 2CMelting point +32 to +127C 61C 63C6.1.2.1 Since separation of liquid column thermometersoccasionally occurs and may escape detection, the ice point ofthe thermometers shal

18、l be checked prior to the test and usedonly if they are accurate within 61C (see Test Method E77).6.1.3 Cork, to fit the test jar, center bored for the testthermometer.6.1.4 Jacket, watertight, cylindrical, metal, flat bottomed,115 6 3 mm depth, with inside diameter of 44.2 to 45.8 mm.It shall be su

19、pported in a vertical position in the cooling bath(6.1.7) so that no more than 25 mm projects out of the coolingmedium. The jacket shall be capable of being cleaned.6.1.5 Disk, cork or felt, 6 mm thick to fit loosely inside thejacket.6.1.6 Gasket, to fit snugly around the outside of the test jarand

20、loosely inside the jacket. The gasket shall be made ofrubber, leather, or other material that is sufficiently elastic tocling to the test jar and hard enough to hold its shape. Itspurpose is to prevent the test jar from touching the jacket.6.1.7 Cooling Bath or Baths, of a type suitable for obtainin

21、gthe required temperatures. The size and shape of the bath areoptions, but a support to hold the jacket firmly in a verticalposition is essential. The bath temperature shall be monitoredby means of the appropriate thermometer (6.1.2) or any othertemperature measuring device capable of measuring and

22、dis-playing the designated temperature with the required precisionand accuracy. The required bath temperatures shall either bemaintained by refrigeration or by suitable freezing mixtures(Note 1) and shall maintain the designated temperatures towithin 61.5C.NOTE 1The cooling mixtures commonly used ar

23、e as follows:For TemperaturesDown toIce and water 9CCrushed ice and sodium chloride crystals 12CCrushed ice and calcium chloride crystals 27CNOTEAll dimensions are stated in millimetres.FIG. 1 Apparatus for Pour Point TestD5853062Acetone or petroleum naphtha (see Section 7)chilled in a covered metal

24、 beaker with anice-salt mixture to 12C and then withenough solid carbon dioxide to give thedesired temperature.57C6.2 Water BathThe size and shape of the bath are op-tional, but a support to hold the test jar immersed in the bath toabove the sample height in the test jar and in a firm verticalpositi

25、on is required. The required bath temperature may bemaintained by any suitable means, provided the temperaturecan be monitored and controlled to the designated temperature(61C (9.1.4; 9.2.4).6.3 Pressure Vessel, constructed of stainless steel accordingto the dimensions given in Fig. 2, and capable o

26、f withstandinga test pressure of 700 kPa. Alternative designs for the pressurevessel cap and synthetic rubber gasket may be used providedthat the internal dimensions of the pressure vessel are the sameas those shown in Fig. 2.NOTE 2This pressure vessel is identical to the pressure vesseldescribed in

27、 Test Method D 130.6.4 Timing Device, capable of measuring up to 30 s with aresolution of at least 0.1 s and an accuracy of 60.2 s or better.7. Reagents and Materials7.1 The following solvents of technical grade are appropri-ate for low-temperature bath media.7.1.1 Acetone,(WarningExtremely flammabl

28、e.)7.1.2 Alcohol, Ethanol,(WarningFlammable.)7.1.3 Alcohol, Methanol,(WarningFlammable. Vaporharmful.)7.1.4 Petroleum Naphtha,(WarningCombustible. Vaporharmful.)NOTE 3Typical petroleum naptha used for cleaning purposes are VMand P napthas.7.2 Toluene, technical grade (WarningFlammable. Vaporharmful.

29、).7.3 Solid Carbon Dioxide,(WarningExtremely cold(78.5C).)8. Sampling, Test Samples, and Test SpecimensNOTE 4Sampling is defined as all steps required to obtain a portion ofthe contents of any pipe, tank, or other system and to place the sample intothe laboratory test container.8.1 Laboratory Sample

30、It is essential that the samplereceived by the laboratory is representative of the batch or lotof crude oil from which it was taken. Practices D 4057 andD 4177 provide guidance for obtaining such representativesamples.8.2 Preparation of Test SamplesThe pour point of crudeoils is very sensitive to tr

31、ace amounts of high melting waxes.Exercise meticulous care to ensure such waxes, if present, areeither completely melted or, if volatility constraints preventheating to complete melting, homogeneously suspended in thesample (Appendix X1). Inspect the walls of the originalcontainer to ensure that no

32、high melting point material is leftsticking to the wall.NOTE 5It is not possible to define universal mandatory rules for thepreparation of crude oil test samples. Guidelines for sample handling forthe most common situations are given in Appendix X1.9. Procedure9.1 Procedure A for Maximum (Upper) Pou

33、r Point:9.1.1 Pour the test sample into the test jar to the level mark.If necessary, reheat the test sample to a temperature at least20C above the expected pour point (8.2 andAppendix X1) butnot higher than a temperature of 60C (WarningThe vaporpressure of crude oils at temperatures higher than 60C

34、willusually exceed 100 kPa. Under these circumstances the samplecontainer may rupture. Opening of the container may inducefoaming with resultant loss of sample and possible injury topersonnel.)9.1.2 Immediately close the test jar with the cork carryingthe high cloud and pour thermometer, or, if the

35、expected pourpoint is above 36C, the melting point thermometer.Adjust theposition of the cork and thermometer so the cork fits tightly, thethermometer and the jar are coaxial, and the thermometer bulbis immersed to a depth that places the beginning of thecapillary 3 mm below the surface of the test

36、specimen.9.1.3 Keep the test jar with the test specimen at roomtemperature (between 18 and 24C) for at least 24 h.NOTE 6The pour point of a crude oil is dependent on the state ofcrystallization of the wax in the test specimen. In crude oils, achievingequilibrium between crystallized wax and dissolve

37、d wax is a rather slowprocess. However, experience has shown that in a majority of cases, suchan equilibrium is reached within 24 h.9.1.4 If the expected pour point is greater than 36C, heatthe sample to 9C above the expected pour point. If theexpected pour point is less than 36C, heat the sample to

38、 atemperature of 45 6 1C. Maintain the water bath (6.2) to heatthe sample at 48 6 1C or at a temperature 12C higher thanthe expected pour point, whichever is higher.9.1.4.1 As soon as the test specimen has reached therequired temperature, remove the cork carrying the thermom-eter and stir the test s

39、pecimen gently with a spatula or similardevice. Put the cork carrying the thermometer back in place(see 9.1.2).9.1.5 Ensure that the disk, gasket, and the inside of thejacket are clean and dry. Place the disk in the bottom of thejacket. Place the disk and jacket in the cooling medium aminimum of 10

40、min before the test jar is inserted. The use ofa jacket cover, while the empty jacket is cooling, is permitted.Remove the test jar from the water bath and dry with a tissue.Place the gasket around the test jar, 25 mm from the bottom.Insert the test jar into the jacket in the first bath maintained at

41、21C and commence observations for pour point. Never placea test jar directly into the cooling medium.9.1.6 Exercise care not to disturb the mass of test specimennor permit the thermometer to shift in the test specimen; anydisturbance of the spongy network of wax crystals will lead toa lower pour poi

42、nt and erroneous results (Note 6).NOTE 7With dark colored materials, such as crude oils, it is imprac-tical to observe, in the test jar, the onset of crystallization and networkformation in the test specimen. Hence, it is presumed that networkformation will begin at the very early stages of the cool

43、ing sequence.D58530639.1.7 Pour points are expressed in temperatures which arepositive or negative multiples of 3C. Begin to examine theappearance of the test specimen when the temperature of thetest specimen is 9C above the expected pour point (estimatedas a multiple of 3C). At each test thermomete

44、r reading whichis a multiple of 3C below the starting temperature, remove thetest jar from the jacket. When necessary, remove moisture thatlimits visibility of the test specimen by wiping the surface ofthe test jar with a clean cloth moistened in alcohol atapproximately the temperature of the test s

45、pecimen in the jar.Then tilt the jar just enough to ascertain whether there ismovement of the test specimen in the jar. When movement isobserved, immediately return the test jar into the jacket. Ifmovement of the specimen in the test jar is noted, then replacethe test jar immediately in the jacket,

46、and repeat a test for flowat the next temperature, 3C lower. Typically the completeoperation of removal, wiping, and replacement shall requirenot more than 3 s.FIG. 2 Pressure VesselD58530649.1.7.1 If the test specimen has not ceased to flow when itstemperature has reached 30C, transfer the test jar

47、 to the nextlower temperature bath per the following schedule:(1) If the test specimen is at +30C, move to 0C bath;(2) If the test specimen is at +9C, move to 18C bath;(3) If the test specimen is at 9C, move to 33C bath;and(4) If the test specimen is at 24C, move to 51C bath.9.1.7.2 If the test spec

48、imen in the jar does not showmovement when tilted, hold the jar in a horizontal position for5 s, as shown by an accurate timing device (6.4), and observethe specimen carefully. If the test specimen shows any move-ment before 5 s has passed, replace the test jar immediately inthe jacket, and repeat a

49、 test for flow at the next temperature,3C lower.9.1.8 Continue in this manner until a point is reached atwhich the test specimen shows no movement when the test jaris held in a horizontal position for 5 s. Record the observedreading of the test temperature.9.1.8.1 If the test specimen has reached 36C and stillshows movement, discontinue the test.NOTE 8To determine compliance with existing specifications havingpour point limits at temperatures not divisible by 3C, it is acceptablepractice to conduct the po