SIST EN ISO 13686:2013
(Main)Natural gas - Quality designation (ISO 13686:2013)
Natural gas - Quality designation (ISO 13686:2013)
This International Standard specifies the parameters required to describe finally processed and, where required, blended natural gas. Such gas is referred to subsequently in this text simply as "natural gas". The main text of this standard contains a list of these parameters, their units and references to measurement standards. Informative annexes give examples of typical values for these parameters, with the main emphasis on health and safety. In defining the parameters governing composition, physical properties and trace constituents, consideration has also been given to existing natural gases to ensure their continuing viability. The question of interchangeability is dealt with in annex A clause A.2.
Erdgas - Bestimmung der Beschaffenheit (ISO 13686:2013)
Die vorliegende Internationale Norm legt Parameter zur Beschreibung von fertig aufbereitetem Erdgas und, wo dies erforderlich ist, von Erdgasgemischen fest. Dieses Gas wird nachstehend als „Erdgas“ bezeichnet.
Der Hauptteil der vorliegenden Norm enthält eine Liste dieser Parameter mit Einheiten und Verweisen auf Messnormen. Darüber hinaus werden in informativen Anhängen zu dieser Norm Beispiele für typische Werte dieser Parameter gegeben, wobei das Hauptaugenmerk auf Gesundheit und Sicherheit gelegt wird.
Bei der Festlegung von Parametern für die Gaszusammensetzung, die physikalischen Eigenschaften und Spurenbestandteile wurden zur Sicherstellung ihrer Gültigkeit vorhandene Erdgase entsprechend berück-sichtigt.
Das Thema Austauschbarkeit wird in Anhang A (siehe A.2) behandelt.
Gaz naturel - Désignation de la qualité (ISO 13686:2013)
L'ISO 13686:2013 traite des paramètres requis pour décrire le gaz naturel dans son état de traitement final et après ajustement, si nécessaire. Ce type de gaz est désigné par la suite dans le texte sous l'appellation «Gaz naturel».
Le texte principal de l'ISO 13686:2013 contient une liste de ces paramètres, leurs unités et références aux normes de mesurage. Les annexes informatives donnent des exemples de valeurs types de ces paramètres, avec un accent principal sur la santé et la sécurité.
Zemeljski plin - Specificiranje kakovosti (ISO 13686:2013)
Ta mednarodni standard določa parametre, ki so potrebni za opredelitev dokončno predelanega in, kjer je to potrebno, mešanega zemeljskega plina. Takšen plin je v nadaljevanju tega besedila naveden kot „zemeljski plin“. Glavno besedilo tega standarda vsebuje seznam teh parametrov, njihove enote in reference merilnih standardov. V informativnih dodatkih so primeri običajnih vrednosti za te parametre, pri čemer sta izpostavljena predvsem zdravje in varnost. Pri opredelitvi parametrov, ki urejajo sestavo, fizične lastnosti in sledi sestavin, so bili upoštevani tudi obstoječi naravni plini ter njihova nadaljnja rentabilnost. Vprašanje zamenljivosti je obravnavano v Dodatku A, točki A.2.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 13686:2013
01-september-2013
1DGRPHãþD
SIST EN ISO 13686:2005
Zemeljski plin - Specificiranje kakovosti (ISO 13686:2013)
Natural gas - Quality designation (ISO 13686:2013)
Erdgas - Bestimmung der Beschaffenheit (ISO 13686:2013)
Gaz naturel - Désignation de la qualité (ISO 13686:2013)
Ta slovenski standard je istoveten z: EN ISO 13686:2013
ICS:
75.060 Zemeljski plin Natural gas
SIST EN ISO 13686:2013 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 13686:2013
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SIST EN ISO 13686:2013
EUROPEAN STANDARD
EN ISO 13686
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2013
ICS 75.060 Supersedes EN ISO 13686:2005
English Version
Natural gas - Quality designation (ISO 13686:2013)
Gaz naturel - Désignation de la qualité (ISO 13686:2013) Erdgas - Bestimmung der Beschaffenheit (ISO
13686:2013)
This European Standard was approved by CEN on 29 May 2013.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same
status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2013 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 13686:2013: E
worldwide for CEN national Members.
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SIST EN ISO 13686:2013
EN ISO 13686:2013 (E)
Contents Page
Foreword .3
2
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SIST EN ISO 13686:2013
EN ISO 13686:2013 (E)
Foreword
This document (EN ISO 13686:2013) has been prepared by Technical Committee ISO/TC 193 "Natural gas".
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by December 2013, and conflicting national standards shall be withdrawn
at the latest by December 2013.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 13686:2005.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech
Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
Endorsement notice
The text of ISO 13686:2013 has been approved by CEN as EN ISO 13686:2013 without any modification.
3
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SIST EN ISO 13686:2013
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SIST EN ISO 13686:2013
INTERNATIONAL ISO
STANDARD 13686
Second edition
2013-06-15
Natural gas — Quality designation
Gaz naturel — Désignation de la qualité
Reference number
ISO 13686:2013(E)
©
ISO 2013
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SIST EN ISO 13686:2013
ISO 13686:2013(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2013
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior
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Published in Switzerland
ii © ISO 2013 – All rights reserved
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SIST EN ISO 13686:2013
ISO 13686:2013(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Symbols, abbreviations and units . 6
4.1 Symbols . 6
4.2 Abbreviations . 6
4.3 Subscripts . 6
5 Quality designation parameters. 7
5.1 General . 7
5.2 Gas composition . 7
5.3 Gas properties . 8
6 Sampling . 9
Annex A (informative) Introduction to informative annexes .10
Annex B (informative) German Regulation Code of Practice DVGW G 260:2008, Extract of the
relevant parts for natural gases .18
Annex C (informative) European Standard EN 437 “Test gases, test pressures and categories of
appliances” .22
Annex D (informative) Interchangeability AGA index method .25
Annex E (informative) British Gas Hydrocarbon Equivalence Method .32
Annex F (informative) Weaver index method .37
Annex G (informative) French method for determining gas interchangeability (Delbourg method)
(guide for determining the interchangeability of second family gases) .39
Annex H (informative) Spanish regulation code (Detail Protocol-01 — Measurement) — Extract of
the relevant parts for natural gases .45
Annex I (informative) Harmonization of gas property data for cross-border transportation .46
Bibliography .48
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SIST EN ISO 13686:2013
ISO 13686:2013(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2. www.iso.org/directives
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received. www.iso.org/patents
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
The committee responsible for this document is ISO/TC 193, Natural gas.
This second edition cancels and replaces the first edition (ISO 13686:1998), which has been
technically revised.
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SIST EN ISO 13686:2013
ISO 13686:2013(E)
Introduction
The need for an International Standard concerning the designation of natural gas quality was a basic
reason for the establishment of ISO/TC 193 in 1989. Standardization of the designation of quality is
specifically stated in the scope of ISO/TC 193. Natural gas, supplying 20 % of the world’s primary energy,
is likely to increase its market share greatly. Yet there is currently no generally accepted definition of
natural gas quality.
To meet this need, it was decided that a general statement of the parameters (i.e. components and
properties) recommended should be established and that the resulting International Standard would
not specify values of, or limits for, these parameters.
Furthermore, it was decided that general-purpose natural gas transmitted to local distribution systems
(LDS), referred to as “natural gas”, should be the first consideration. Thus, this International Standard
was developed. Informative annexes are attached as examples of actual natural gas quality specifications
that already exist.
This International Standard does not impose any quality restrictions on raw gas transported via
pipelines or gathering systems to processing or treating facilities.
It should be understood that this International Standard covers natural gas at the pipeline level prior to
any treatment by LDS for peakshaving purposes. This covers the vast majority of the natural gas that is
sold in international trade and transmitted for custody transfer to local distribution systems.
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SIST EN ISO 13686:2013
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SIST EN ISO 13686:2013
INTERNATIONAL STANDARD ISO 13686:2013(E)
Natural gas — Quality designation
1 Scope
This International Standard specifies the parameters required to describe finally processed and, where
required, blended natural gas. Such gas is referred to subsequently in this text simply as “natural gas”.
The main text of this International Standard contains a list of these parameters, their units and references
to measurement standards. Informative annexes give examples of typical values for these parameters,
with the main emphasis on health and safety.
In defining the parameters governing composition, physical properties and trace constituents,
consideration has also been given to existing natural gases to ensure their continuing viability.
The question of interchangeability is dealt with in Annex A (see Clause A.2).
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 6326-1, Natural gas — Determination of sulfur compounds — Part 1: General introduction
ISO 6326-3, Natural gas — Determination of sulfur compounds — Part 3: Determination of hydrogen sulfide,
mercaptan sulfur and carbonyl sulfide sulfur by potentiometry
ISO 6326-5, Natural gas — Determination of sulfur compounds — Part 5: Lingener combustion method
ISO 6327, Gas analysis — Determination of the water dew point of natural gas — Cooled surface
condensation hygrometers
ISO 6570, Natural gas — Determination of potential hydrocarbon liquid content — Gravimetric methods
ISO 6974-1, Natural gas — Determination of composition and associated uncertainty by gas
chromatography — Part 1: General guidelines and calculation of composition
ISO 6974-2, Natural gas — Determination of composition and associated uncertainty by gas
chromatography — Part 2: Uncertainty calculations
ISO 6974-3, Natural gas — Determination of composition with defined uncertainty by gas chromatography —
Part 3: Determination of hydrogen, helium, oxygen, nitrogen, carbon dioxide and hydrocarbons up to C8
using two packed columns
ISO 6974-4, Natural gas — Determination of composition with defined uncertainty by gas chromatography —
Part 4: Determination of nitrogen, carbon dioxide and C1 to C5 and C6+ hydrocarbons for a laboratory and
on-line measuring system using two columns
ISO 6974-5, Natural gas — Determination of composition and associated uncertaint y by gas chromatography —
Part 5: Isothermal method for nitrogen, carbon dioxide, C1 to C5 hydrocarbons and C6+ hydrocarbons
ISO 6974-6, Natural gas — Determination of composition and associated uncertainty by gas
chromatography — Part 6: Determination of helium, oxygen, nitrogen, carbon dioxide and C1 to C10
hydrocarbons using capaillary columns
ISO 6975, Natural gas — Extended analysis — Gas-chromatographic method
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SIST EN ISO 13686:2013
ISO 13686:2013(E)
ISO 6976:1995, Natural gas — Calculation of calorific values, density, relative density and Wobbe index
from composition
ISO 6978-1, Natural gas — Determination of mercury — Part 1: Sampling of mercury by chemisorption on iodine
ISO 6978-2, Natural gas — Determination of mercury — Part 2: Sampling of mercury by amalgamation on
gold/platinum alloy
ISO 10101-1, Natural gas — Determination of water by the Karl Fischer method — Part 1: Introduction
ISO 10101-2, Natural gas — Determination of water by the Karl Fischer method — Part 2: Titration procedure
ISO 10101-3, Natural gas — Determination of water by the Karl Fischer method — Part 3: Coulometric procedure
ISO 11541, Natural gas — Determination of water content at high pressure
ISO 13443, Natural gas — Standard reference conditions
ISO 14532, Natural gas — Vocabulary
ISO 15970:2008, Natural gas — Measurement of properties — Volumetric properties: density, pressure,
temperature and compression factor
ISO 15971:2008, Natural gas — Measurement of properties — Calorific value and Wobbe index
ISO 18453, Natural gas — Correlation between water content and water dew point
ISO 19739, Natural gas — Determination of sulfur compounds using gas chromatography
ISO 23874, Natural gas — Gas chromatographic requirements for hydrocarbon dewpoint calculation
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 14532 and the following apply.
3.1
natural gas
gaseous fuel obtained from underground sources and consisting of a complex mixture of hydrocarbons,
primarily methane, but generally also including ethane, propane and higher hydrocarbons in much
smaller amounts
Note 1 to entry: It also includes some inert gases, such as nitrogen and carbon dioxide, plus minor amounts of
trace constituents.
Note 2 to entry: Natural gas remains in the gaseous state under the temperature and pressure conditions normally
found in service. It is produced by processing raw gas or from liquefied natural gas and, if required, blended to give
a gas suitable for direct use. As pipeline quality natural gas, it can then be transmitted within a local distribution
system, within a country, or across national borders. It is subject to contractual requirements between buyer and
seller, and in some cases to national or state requirements as to quality (see Clause A.1).
3.2
liquefied natural gas
natural gas which, after processing, has been liquefied for storage or transportation purposes
Note 1 to entry: Liquefied natural gas is revaporized and introduced into pipelines for transmission and
distribution as natural gas.
3.3
substitute natural gas
manufactured or blended gas with properties which make it interchangeable with natural gas
Note 1 to entry: Substitute natural gas is sometimes called synthetic natural gas.
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SIST EN ISO 13686:2013
ISO 13686:2013(E)
Note 2 to entry: This also includes gases manufactured by thermal process from biomass.
3.4
raw gas
unprocessed gas taken from well heads through gathering lines to processing facilities
3.5
local distribution system
gas mains and services which supply natural gas directly to consumers
3.6
gas quality
attribute of natural gas by its composition (major components, minor components and trace components)
and its physical properties (calorific value, Wobbe index, compression factor, relative density and dew points)
3.7
reference conditions
standard reference conditions of temperature, pressure and humidity (state of saturation) to be used for
measurements and calculations carried out on natural gases, natural gas substitutes and similar fluids
in the gaseous state
Note 1 to entry: Standard reference conditions are denoted by the subscript “s”: p = 101,325 kPa; T = 288,15 K.
s s
Note 2 to entry: Adapted from ISO 13443.
3.8
calorific value
amount of heat which would be released by the complete combustion in air of a specified quantity of gas,
in such a way that the pressure at which the reaction takes place remains constant, and all the products
of combustion are returned to the same specified temperature as that of the reactants
Note 1 to entry: It is divided into two types: superior calorific value and inferior calorific value.
Note 2 to entry: Both superior and inferior calorific values, which differ by the heat of condensation of water
formed by combustion, can be specified on a molar, mass or volumetric basis. For the volumetric basis the pressure
and temperature shall be stated at standard reference conditions.
Note 3 to entry: Calorific values can also be stated as dry or wet, depending on the water vapour content of the
gas prior to combustion.
Note 4 to entry: The effect of water vapour on the calorific values, either directly measured or calculated, is
described in Annex F of ISO 6976:1995.
Note 5 to entry: Normally, the calorific value is expressed as the superior, dry value specified as a volumetric basis
under standard reference conditions.
Note 6 to entry: Adapted from ISO 6976.
3.8.1
superior calorific value
amount of heat that would be released by the complete combustion with oxygen of a specified quantity
of gas, in such a way that the pressure p at which the reaction takes place remains constant, and all the
1
products of combustion are returned to the same specified temperature t as that of the reactants, all
1
of these products being in the gaseous state except for water, which is condensed to the liquid state at t
1
Note 1 to entry: Adapted from ISO 6976.
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SIST EN ISO 13686:2013
ISO 13686:2013(E)
3.8.2
inferior calorific value
amount of heat that would be released by the complete combustion with oxygen of a specified quantity
of gas, in such a way that the pressure p at which the reaction takes place remains constant, and all the
1
products of combustion are returned to the same specified temperature t as that of the reactants, all of
1
these products being in the gaseous state
Note 1 to entry: Adapted from ISO 6976.
3.9
density
mass of a gas divided by its volume at specified pressure and temperature
3.10
relative density
density of a gas divided by the density of dry air of standard composition at the same specified conditions
of pressure and temperature
Note 1 to entry: The term “ideal relative density” applies when both gas and air are considered as fluids which
obey the ideal gas law; the term “real relative density” applies when both gas and air are considered as real fluids.
For the standard composition of dry air.
Note 2 to entry: Adapted from ISO 6976.
3.11
Wobbe index
volumetric-basis superior (inferior) calorific value, at specified reference conditions, divided by the
square root of the relative density at the same specified metering reference conditions
Note 1 to entry: The heat input for different natural gas compositions is the same if they have the same Wobbe
index and are used under the same gas pressure.
Note 2 to entry: Adapted from ISO 6976.
3.12
compression factor
compression factor Z is the quotient of the volume of an arbitrary mass of gas, at a specified pressure and
temperature, and that of the same gas under the same conditions as calculated from the ideal gas law
Note 1 to entry: The terms “compressibility factor” and “Z-factor” are synonymous with compression factor.
Note 2 to entry: Adapted from ISO 12213-1.
3.13
water dew point
temperature above which no condensation of water occurs at a specified pressure
Note 1 to entry: For any pressure lower than the specified pressure there is no condensation at this temperature.
Note 2 to entry: Adapted from ISO 6327.
3.14
hydrocarbon dew point
temperature above which no condensation of hydrocarbons occurs at a specified pressure
Note 1 to entry: At a given dew point, there is a pressure range within which condensation occurs except at one
point, the cricondentherm (see A.3.2).
3.15
gas composition
concentrations of the major and minor components and trace components in natural gas as analysed
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SIST EN ISO 13686:2013
ISO 13686:2013(E)
3.16
molar composition
gas composition expressed as a molar (or mole) fraction, or molar (mole) percentage
Note 1 to entry: The mole fraction, x, of component i is the quotient of amount of substance of this component and
amount of substance of the whole mixture. The unit of amount of substance is mole. The mass of one mole of any
chemical species, in grams, is numerically equal to its relative molecular mass. A table of recommended values of
molar masses is given in ISO 6976. For an ideal gas, the mole fraction is identical to the volume fraction, but this
relationship cannot in general be assumed to apply to real gas behaviour.
3.17
gas analysis
use of test methods and other techniques for determining the gas composition, as stated in this
International Standard
3.18
interchangeability
measure of the degree to which the combustion characteristics of one gas resemble those of another gas
Note 1 to entry: Two gases are said to be interchangeable when one gas may be substituted for the other without
affecting the operation of gas burning appliances or equipment.
3.19
odorization
addition of odorants, in most cases intensively smelling organic sulfur compounds, to natural gas to
allow the recognition of gas leaks by smell at very low concentration (before a build up to a dangerous
gas in air concentration can occur)
Note 1 to entry: Natural gas is normally odourless. It is necessary to add an odorant to the gas for safety reasons.
It permits the detection of the gas by smell at very low concentrations.
Note 2 to entry: Odorants in use for gas odorization are specified in ISO 13734.
3.20
methane number
rating indicating the knocking characteristics of a fuel gas
Note 1 to entry: It is comparable to the octane number for petrol.
Note 2 to entry: The methane number expresses the volume percentage of methane in a methane/hydrogen mixture
which, in a test engine under standard conditions, has the same tendency to knock as the fuel gas to be examined.
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SIST EN ISO 13686:2013
ISO 13686:2013(E)
4 Symbols, abbreviations and units
4.1 Symbols
Symbol Meaning and units
d Relative density
Molar basis calorific value (kJ/mol)
H
ˆ Mass basis calorific value (MJ/kg)
H
3
Volumetric basis calorific value (MJ/m )
H
M Mass per mole (kg/kmol)
p (Absolute) pressure (kPa)
t Celsius temperature (°C)
T Thermodynamic (absolute) temperature (K)
3
V (Gas) volume (m )
3
W Wobbe index (number) (MJ/m )
Z Compression factor
3
D Density (kg/m )
4.2 Abbreviations
Abbreviation Meaning
LDS Local distribution system
NG Natural gas
SNG Substitute (synthetic) natural gas
4.3 Subscripts
d (Gas volume) dry
l Inferior (calorific value)
s (Gas volume) saturated
S Superior (calorific value)
w (Gas volume) wet
Superior calorific value is denoted by Hs; inferior calorific value is denoted by H . The calorific value
I
shall be specified under the combustion conditions. The volumetric calorific value shall be specified
under standard reference conditions. The calorific value is normally stated as “dry”.
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SIST EN ISO 13686:2013
ISO 13686:2013(E)
EXAMPLE Superior calorific value, specified on a volumetric basis, at standard reference conditions and
stated as wet. For simplicity, the combustion conditions are not specified.
Hp(,T )
S,ws s
The Wobbe index, denoted by W, is expressed on a volumetric basis and given in MJ/m3, where the
volume is stated at standard reference conditions. The Wobbe index can be specified as superior or
inferior, depending on the calorific value and as dry or wet, depending on the calorific value and the
corresponding density.
EXAMPLE Wobbe index, superior, specified an a volumetric basis, at standard reference conditions and
stated as “wet”.
Hp(,T )
S,ws s
Wp(,T )=
S,ws s
dp(,T )
ws s
5 Quality designation parameters
5.1 General
This clause deals with the various parameters which may be referred to in a designation of the quality of
natural gas. The parameters actually selected will depend upon the purpose for which the designation
is required and it is unlikely that all the parameters listed in this International Standard will be used.
5.2 Gas composition
5.2.1 General
Natural gas is compo
...
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