ASTM D7061-19e1
(Test Method)Standard Test Method for Measuring n-Heptane Induced Phase Separation of Asphaltene-Containing Heavy Fuel Oils as Separability Number by an Optical Scanning Device
Standard Test Method for Measuring n-Heptane Induced Phase Separation of Asphaltene-Containing Heavy Fuel Oils as Separability Number by an Optical Scanning Device
SIGNIFICANCE AND USE
5.1 This procedure describes a rapid and sensitive method for estimating the stability reserve of an oil. The stability reserve is estimated in terms of a separability number, where a low value of the separability number indicates that there is a stability reserve within the oil. When the separability number is between 0 to 5, the oil can be considered to have a high stability reserve and asphaltenes are not likely to flocculate. If the separability number is between 5 to 10, the stability reserve in the oil will be much lower. However, asphaltenes are, in this case, not likely to flocculate as long as the oil is not exposed to any worse conditions, such as storing, aging, and heating. If the separability number is above 10, the stability reserve of the oil is very low and asphaltenes will easily flocculate, or have already started to flocculate.
5.2 This test method can be used by refiners and users of oils, for which this test method is applicable, to estimate the stability reserves of their oils. Hence, this test method can be used by refineries to control and optimize their refinery processes. Consumers of oils can use this test method to estimate the stability reserve of their oils before, during, and after storage.
FIG. 1 Schematic Representation of a Typical Measurement Using an Optical Scanning Device
5.3 This test method is not intended for predicting whether oils are compatible before mixing, but can be used for determining the separability number of already blended oils. However, oils that show a low separability number are more likely to be compatible with other oils than are oils with high separability numbers.
SCOPE
1.1 This test method covers the quantitative measurement, either in the laboratory or in the field, of how easily asphaltene-containing heavy fuel oils diluted in toluene phase separate upon addition of heptane. This is measured as a separability number (%) by the use of an optical scanning device.
1.2 The test method is limited to asphaltene-containing heavy fuel oils. ASTM specification fuels that generally fall within the scope of this test method are Specification D396, Grade Nos. 4, 5, and 6, Specification D975, Grade No. 4-D, and Specification D2880, Grade Nos. 3-GT and 4-GT. Refinery fractions from which such blended fuels are made also fall within the scope of this test method.
1.3 The values stated 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 responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
General Information
Relations
Standards Content (Sample)
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
´1
Designation: D7061 − 19
Standard Test Method for
Measuring n-Heptane Induced Phase Separation of
Asphaltene-Containing Heavy Fuel Oils as Separability
1
Number by an Optical Scanning Device
This standard is issued under the fixed designation D7061; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1
ε NOTE—Editorially updated Eq 2 and Eq 3 in April 2020.
1. Scope* 2. Referenced Documents
2
1.1 This test method covers the quantitative measurement, 2.1 ASTM Standards:
eitherinthelaboratoryorinthefield,ofhoweasilyasphaltene- D396 Specification for Fuel Oils
containing heavy fuel oils diluted in toluene phase separate D975 Specification for Diesel Fuel
upon addition of heptane. This is measured as a separability D2880 Specification for Gas Turbine Fuel Oils
number (%) by the use of an optical scanning device. D4057 Practice for Manual Sampling of Petroleum and
Petroleum Products
1.2 The test method is limited to asphaltene-containing
D4177 Practice for Automatic Sampling of Petroleum and
heavy fuel oils. ASTM specification fuels that generally fall
Petroleum Products
within the scope of this test method are Specification D396,
Grade Nos. 4, 5, and 6, Specification D975, Grade No. 4-D,
3. Terminology
andSpecificationD2880,GradeNos.3-GTand4-GT.Refinery
3.1 Definitions:
fractions from which such blended fuels are made also fall
3.1.1 asphaltenes, n—(rarely used in the singular), in petro-
within the scope of this test method.
leum technology, represent an oil fraction that is soluble in a
1.3 The values stated in SI units are to be regarded as
specified aromatic solvent but separates upon addition of an
standard. No other units of measurement are included in this
excess of a specified paraffinic solvent.
standard.
3.1.1.1 Discussion—In this test method, the aromatic sol-
1.4 This standard does not purport to address all of the
vent is toluene and the paraffinic solvent is heptane.
safety concerns, if any, associated with its use. It is the
3.1.2 compatibility, n—of crude oils or of heavy fuel oils,
responsibility of the user of this standard to establish appro-
the ability of two or more crude oils or fuel oils to blend
priate safety, health, and environmental practices and deter-
together within certain concentration ranges without evidence
mine the applicability of regulatory limitations prior to use.
of separation, such as the formation of multiple phases.
1.5 This international standard was developed in accor-
3.1.2.1 Discussion—Incompatible heavy fuel oils or crude
dance with internationally recognized principles on standard-
oils, when mixed or blended, result in the flocculation or
ization established in the Decision on Principles for the
precipitation of asphaltenes. Some oils may be compatible
Development of International Standards, Guides and Recom-
within certain concentration ranges in specific mixtures, but
mendations issued by the World Trade Organization Technical
incompatible outside those ranges.
Barriers to Trade (TBT) Committee.
3.1.3 flocculation, n—of asphaltenes from crude oils or
heavy fuel oils, the aggregation of colloidally dispersed as-
phaltenes into visibly larger masses that may or may not settle.
1
This test method is under the jurisdiction of ASTM Committee D02 on
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of
2
Subcommittee D02.14 on Stability, Cleanliness and Compatibility of Liquid Fuels. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Dec. 1, 2019. Published January 2020. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
approved in 2004. Last previous edition approved in 2017 as D7061 – 17. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/D7061-19E01. the ASTM website.
*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
1
---------------------- Page: 1 ----------------------
´1
D7061 − 19
3.1.4 peptization, n—of asphaltenes in crude oils or heavy transmittance is calculated from 1125 readings at 0.04 mm
fuel oils, the dispersion of asphaltenes to produce a colloidal intervals along the glass vial, starting 10 mm above the bottom
dispersion. of the vial and continuing up to 55 mm for each scan. The
separability number from 16 scans is
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.