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ASTM D8098-17

(Test Method)

Standard Test Method for Permanent Gases in C2 and C3 Hydrocarbon Products by Gas Chromatography and Pulse Discharge Helium Ionization Detector

Standard Test Method for Permanent Gases in C<inf>2</inf> and C<inf>3</inf> Hydrocarbon Products by Gas Chromatography and Pulse Discharge Helium Ionization Detector

SIGNIFICANCE AND USE
5.1 The presence of trace amounts of hydrogen, oxygen, carbon monoxide, and carbon dioxide can have deleterious effects in certain processes using hydrocarbon products as feed stock. This test method is suitable for setting specifications, for use as an internal quality control tool, and for use in development and research work.
SCOPE
1.1 This test method covers the determination of hydrogen, nitrogen, oxygen, methane, carbon monoxide, and carbon dioxide in the parts per billion mole (nmol/mol) to parts per million mole (µmol/mol) range in C2 and C3 hydrocarbons.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 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 and health practices and determine the applicability of regulatory limitations prior to use. For some specific hazard statements, see Annex A1.  
1.4 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

Status
Historical
Publication Date
14-Jul-2017
ICS
75.060 - Natural gas
Technical Committee
D02 - Petroleum Products, Liquid Fuels, and Lubricants
Drafting Committee
D02.D0.02 - Ethylene
Current Stage
Ref Project

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ASTM D8098-17 - Standard Test Method for Permanent Gases in C<inf>2</inf> and C<inf>3</inf> Hydrocarbon Products by Gas Chromatography and Pulse Discharge Helium Ionization DetectorASTM D8098-17 - Standard Test Method for Permanent Gases in C<inf>2</inf> and C<inf>3</inf> Hydrocarbon Products by Gas Chromatography and Pulse Discharge Helium Ionization Detector
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ASTM D8098-17 - Standard Test Method for Permanent Gases in C<inf>2</inf> and C<inf>3</inf> Hydrocarbon Products by Gas Chromatography and Pulse Discharge Helium Ionization Detector
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Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D8098 − 17
Standard Test Method for
Permanent Gases in C and C Hydrocarbon Products by
2 3
Gas Chromatography and Pulse Discharge Helium
1
Ionization Detector
This standard is issued under the fixed designation D8098; 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. Scope D7915 Practice for Application of Generalized Extreme
Studentized Deviate (GESD) Technique to Simultane-
1.1 This test method covers the determination of hydrogen,
ously Identify Multiple Outliers in a Data Set
nitrogen, oxygen, methane, carbon monoxide, and carbon
E260 Practice for Packed Column Gas Chromatography
dioxide in the parts per billion mole (nmol/mol) to parts per
F307 Practice for Sampling Pressurized Gas for Gas Analy-
million mole (µmol/mol) range in C and C hydrocarbons.
2 3
sis
3
1.2 The values stated in SI units are to be regarded as
2.2 Other Standards:
standard. No other units of measurement are included in this
G-4 and G-4.1, Compressed Gas Association Booklet on the
standard.
Use of Oxygen
1.3 This standard does not purport to address all of the
3. Terminology
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
3.1 For definitions of terms used in this standard, see
priate safety and health practices and determine the applica-
Terminology D4175.
bility of regulatory limitations prior to use. For some specific
4. Summary of Test Method
hazard statements, see Annex A1.
1.4 This international standard was developed in accor-
4.1 The sample is separated in a gas chromatographic
dance with internationally recognized principles on standard-
system using gas chromatography columns. Hydrogen,
ization established in the Decision on Principles for the
oxygen, nitrogen, methane, carbon monoxide, and carbon
Development of International Standards, Guides and Recom-
dioxide (also known as the permanent gases) are detected on a
mendations issued by the World Trade Organization Technical
pulse discharge detector. The concentration of the gases to be
Barriers to Trade (TBT) Committee.
determined is calculated from the peak areas relative to an
external standard. Helium is the required carrier gas for this
2. Referenced Documents
detector. Ultra-high purity carrier gases and leak-free gas
2
chromatography (GC) systems with getters are essential due to
2.1 ASTM Standards:
the extreme sensitivity of the detector. Argon, if present in the
D2505 Test Method for Ethylene, Other Hydrocarbons, and
sample, may interfere with oxygen determination.
Carbon Dioxide in High-Purity Ethylene by Gas Chroma-
tography
5. Significance and Use
D4175 Terminology Relating to Petroleum Products, Liquid
Fuels, and Lubricants 5.1 The presence of trace amounts of hydrogen, oxygen,
D6300 Practice for Determination of Precision and Bias carbon monoxide, and carbon dioxide can have deleterious
Data for Use in Test Methods for Petroleum Products and effects in certain processes using hydrocarbon products as feed
Lubricants stock. This test method is suitable for setting specifications, for
use as an internal quality control tool, and for use in develop-
ment and research work.
1
This test method is under the jurisdiction of ASTM Committee D02 on
6. Apparatus
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of
Subcommittee D02.D0.02 on Ethylene.
6.1 Chromatograph—Any gas chromatograph capable of
Current edition approved July 15, 2017. Published September 2017. DOI:
maintaining the temperatures, pressures, and flows necessary
10.1520/D8098-17.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
3
Standards volume information, refer to this standard’s Document Summary page on Available from Compressed Gas Association (CGA), 14501 George Carter
the ASTM website. Way, Suite 103, Chantilly, VA 20151, http://www.cganet.com.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D8098 − 17
for this analyses. The GC should also be capable of tempera- adsorptive with respect to the components in the sample. The
ture programming of the oven to obtain optimum separation of preferred material of construction is stainless steel. Copper,
the components. A typical configuration is shown in Fig. 1. brass, and other copper-bearing alloys are unacceptable. The
analysis of oxygen and carbon monoxide may benefit from the
6.2 Detectors—(PDHID Pu
...

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Standard Test Method for Permanent Gases in C2 and C3 Hydrocarbon Products by Gas Chromatography and Pulse Discharge Helium Ionization Detector

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5.1 The presence of trace amounts of hydrogen, oxygen, carbon monoxide, and carbon dioxide can have deleterious effects in certain processes using hydrocarbon products as feed stock. This test method is suitable for setting specifications, for use as an internal quality control tool, and for use in development and research work.
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4.1 Trace quantities of sulfur compounds in hydrocarbon products can be harmful to many catalytic chemical processes in which these products are used. Maximum permissible levels of total sulfur are normally included in specifications for such hydrocarbons. It is recommended that this test method be used to provide a basis for agreement between two laboratories when the determination of sulfur in hydrocarbon gases is important.  
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ASTM D8251-23(Practice)
Standard Practice for Determining Compressor Oil Carryover in Compressed Natural Gas Used as a Natural Gas Motor Vehicle Fuel

SIGNIFICANCE AND USE
5.1 Uncontrolled oil carryover from lubricated natural gas compressors can adversely affect natural gas vehicle (NGV) performance. In some instances, small amounts of oil will accumulate in vehicle pressure regulators and slow their response. It can also affect other components of the engine fueling system. Erratic engine performance, under fueling, or engine shutdown can occur. Such incidents have been reported by operators of NGV fueling stations and vehicles.  
5.2 There is some vaporization of the lubrication (lube) oil that occurs due to compression of the gas. The oil vapor in CNG can be collected using a sorbent tube and quantified. Along with quantification of lube oil, this procedure can collect solids present in the gas.  
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1.1 This standard practice is intended for gravimetric determination of compressor oil carryover as aerosols using either a coalescing filter method or sorbent tube method.  
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5.1 Elemental sulfur impacts the quality of pipeline natural gas and deposits on pipeline flanges, fittings and valves, thereby impacting their performance. Natural gas suppliers and distributers require a standardized test method for measuring elemental sulfur. Some government regulators are also interested in measuring elemental sulfur since it would provide a means for assessing the contribution of elemental sulfur in pipelines to the SOx emission inventory from burning of gaseous fuels. Use of this method in concert with sulfur gas laboratory test methods such as Test Methods D4084, D4468, D5504, and D6228 or on-line methods such as D7165 or D7166 can provide users with a comprehensive sulfur compound profile for natural gas or other gaseous fuels. Other applications may include elemental sulfur in particulate deposits such as diesel exhausts.
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ASTM D4784-23(Specification)
Standard Specification for Liquefied Natural Gas Density Calculation Models

ABSTRACT
This specification covers LNG density calculation models for use in the calculation or prediction of the densities of saturated liquefied natural gas (LNG) mixtures at a specified temperature range given the pressure, temperature, and composition of the mixture. Composition restrictions for the LNGs are given for methane, nitrogen, n-butane, i-butane, and pentanes. It is assumed that hydrocarbons with carbon numbers of six or greater are not present in the LNG solution. The mathematical models presented here are the extended corresponding states model, hard sphere model, revised Klosek and McKinley model, and the cell model.
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1.1 This test method is for the online determination of hydrogen sulfide (H2S) in natural gas using tunable diode laser absorption spectroscopy (TDLAS) analyzers also known as a “TDL analyzers.” The particular wavelength for H2S measurement varies by manufacturer, typically between 1000 and 10 000 nm with an individual laser having a tunable range of less than 10 nm. The H2S concentration ranges can be anywhere from 0-5 ppm(v) to 0-90 % by volume.  
1.2 Units—The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard. TDLAS analyzers inherently output concentrations in unitless molar ratios such as ppm(v).
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5.1 This test method can be used to measure the level of mercury in any gaseous fuel (as defined by Terminology D4150) for purposes such as determining compliance with regulations, studying the effect of various abatement procedures on mercury emissions, checking the validity of direct instrumental measurements, and verifying that mercury concentrations are below those required for gaseous fuel processing and operations.  
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1.1 This test method covers the determination of total mercury in gaseous fuels at concentrations down to 0.5 ng/m3. It includes separate procedures for both sampling and atomic absorption spectrophotometric determination of mercury. This procedure detects both inorganic and organic forms of mercury.  
1.2 Units—The values stated in SI units are to be regarded as the standard.  
1.3 Warning—Mercury has been designated by many regulatory agencies as a hazardous material that can cause serious medical issues. Mercury, or its vapor, has been demonstrated to be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury containing products. See the applicable product Safety Data Sheet (SDS) for additional information. Users should be aware that selling mercury or mercury containing products, or both, into your state or country may be prohibited by law.  
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ASTM D7904-21(Test Method)
Standard Test Method for Determination of Water Vapor (Moisture Concentration) in Natural Gas by Tunable Diode Laser Spectroscopy (TDLAS)

SIGNIFICANCE AND USE
5.1 Moisture measurement in natural gas is performed to ensure sufficiently low levels for gas purchase contracts and to prevent corrosion. Moisture may also contribute to the formation of hydrates.  
5.2 The significance of applying TDLAS for the measurement of moisture in natural gas is TDLAS analyzers may have a very high degree of selectivity and minimal interference in many natural gas streams. Additionally, the sensing components of the analyzer are not wetted by the natural gas, limiting the potential damage from corrosives such as hydrogen sulfide (H2S) and liquid contaminants such as ethylene glycol or compressor oils. As a result, the TDLAS analyzer is able to detect changes in concentration with relatively rapid response. It should be noted that the mirrors of a TDLAS analyzer may be fouled if large quantities of condensed liquids enter the sample cell. In most cases the mirror can be cleaned without the need for recalibration or realignment.  
5.3 Primary applications covered in this method are listed in 5.3.1 – 5.3.3. Each application may have differing requirements and methods for gas sampling. Additionally, different natural gas applications may have unique spectroscopic considerations.  
5.3.1 Raw natural gas is found in production, gathering sites, and inlets to gas-processing plants characterized by potentially high levels of water (H2O), carbon dioxide (CO2), hydrogen sulfide (H2S), and heavy hydrocarbons. Gas-conditioning plants and skids are normally used to remove H2O, CO2, H2S, and other contaminants. Typical moisture concentration after dehydration is roughly 20 to 200 ppmv. Protection from liquid carryover such as heavy hydrocarbons and glycols in the sample lines is necessary to prevent liquid pooling in the cell or the sample components.  
5.3.2 Underground gas storage facilities are high-pressure caverns used to store large volumes of gas for use during peak demand. Underground storage caverns can reach pressures as high as 275 bar. ...
SCOPE
1.1 This test method covers online determination of vapor phase moisture concentration in natural gas using a tunable diode laser absorption spectroscopy (TDLAS) analyzer also known as a “TDL analyzer.” The particular wavelength for moisture measurement varies by manufacturer; typically between 1000 and 10 000 nm with an individual laser having a tunable range of less than 10 nm.  
1.2 Process stream pressures can range from 700-mbar to 700-bar gage. TDLAS is performed at pressures near atmospheric (700- to 2000-mbar gage); therefore, pressure reduction is typically required. TDLAS can be performed in vacuum conditions with good results; however, the sample conditioning requirements are different because of higher complexity and a tendency for moisture ingress and are not covered by this test method. Generally speaking, the vent line of a TDL analyzer is tolerant to small pressure changes on the order of 50 to 200 mbar, but it is important to observe the manufacturer’s published inlet pressure and vent pressure constraints. Large spikes or steps in backpressure may affect the analyzer readings.  
1.3 The typical sample temperature range is -20 to 65 °C in the analyzer cell. While sample system design is not covered by this standard, it is common practice to heat the sample transport line to around 50 °C to avoid concentration changes associated with adsorption and desorption of moisture along the walls of the sample transport line.  
1.4 The moisture concentration range is 1 to 10 000 parts per million by volume (ppmv). It is unlikely that one spectrometer cell will be used to measure this entire range. For example, a TDL spectrometer may have a maximum measurement of 1 ppmv, 100 ppmv, 1000 ppmv, or 10 000 ppmv with varying degrees of accuracy and different lower detection limits.  
1.5 TDL absorption spectroscopy measures molar ratios such as ppmv or mole percentage. Volumetric ratios (ppmv and %) are not pressure d...

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ASTM D7940-21(Practice)
Standard Practice for Analysis of Liquefied Natural Gas (LNG) by Fiber-Coupled Raman Spectroscopy

SIGNIFICANCE AND USE
5.1 The composition of liquefied gaseous fuels (LNG, LPG) is important for custody transfer and production. Compositional determination is used to calculate the heating value, and it is important to ensure regulatory compliance. Compositional determination is also used to optimize the efficiency of liquefied hydrocarbon gas production and ensure the quality of the processed fluids.  
5.2 Alternatives to compositional measurement using Raman spectroscopy are described in Test Method D1945, Practice D1946, and Test Method D7833.  
5.3 The advantage of this practice over other standards stated in 5.2, is that Raman spectroscopy can determine composition by directly measuring the liquefied natural gas. Unlike chromatography, no vaporization step is necessary. Since incorrect operation of on-line vaporizers can lead to poor precision and accuracy, elimination of the vaporization step offers a significant improvement in the analysis of LNG.
SCOPE
1.1 This practice is for both on-line and laboratory instrument-based determination of composition for liquefied natural gas (LNG) using Raman spectroscopy. Although the procedures in this practice refer specifically to liquids, the basic methodology can also be applied to other light hydrocarbon mixtures in either liquid or gaseous states, provided the data quality objectives and measurement needs are met. From the composition, gas properties such as heating value and the Wobbe index may be calculated. The components commonly determined according to this test method are CH4, C2H6, C3H8, i-C4H10, n-C4H10, iC5H12, n-C5H12. Components heavier than C5 are not measured as part of this practice.
Note 1: Raman spectroscopy does not directly quantify the component percentages of noble gases; however, inert substances can be calculated indirectly by subtracting the sum of the other species from 100 %.  
1.2 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 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.  
1.4 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.

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