EN ISO 14912:2025
(Main)Gas analysis - Conversion of gas mixture composition data (ISO 14912:2025)
Gas analysis - Conversion of gas mixture composition data (ISO 14912:2025)
This document defines the following quantities commonly used to express the composition of gas mixtures:
— amount fraction and concentration;
— mass fraction and concentration;
— volume fraction and concentration.
For these quantities of composition, this document specifies methods for:
— conversion between different quantities;
— conversion between different state conditions.
Conversion between different quantities means calculating the value of the content of a specified component in terms of one of the quantities listed above from the value of the same content, at the same pressure and temperature of the gas mixture, given in terms of another of these quantities. Conversion between different state conditions means calculating the value of the content of a specified component, in terms of one of the quantities listed above, under one set of state conditions from the value of the same quantity under another set of state conditions, i.e., pressure and temperature, of the gas mixture. Gas mixture composition can be converted simultaneously between different quantities of composition and different state conditions by combination of the two types of conversion.
This document is applicable only to homogeneous and stable gas mixtures. Therefore, any state conditions (pressure and temperature) considered need to be well outside the condensation region of the gas mixture. In addition, volume concentrations can only be used if the component under consideration is completely gaseous, and for the use of volume fractions, all components need to be completely gaseous. Further restrictions of state conditions apply for approximations of compression factors using virial coefficients (see Annex A).
Gasanalyse - Umrechnung von Zusammensetzungsangaben für Gasgemische (ISO 14912:2025)
Dieses Dokument definiert die folgenden Größen, die zur Angabe der Zusammensetzung von Gasgemischen verwendet werden:
Stoffmengenanteil und Stoffmengenkonzentration;
Massenanteil und Massenkonzentration;
Volumenanteil und Volumenkonzentration.
Für die genannten Zusammensetzungsgrößen legt dieses Dokument Verfahren fest zur:
Umrechnung zwischen verschiedenen Größen;
Umrechnung zwischen verschiedenen Zustandsbedingungen.
Umrechnung zwischen verschiedenen Größen bedeutet Berechnung des Werts des Gehalts einer festgelegten Komponente in einer der oben genannten Größen aus dem Wert desselben Gehalts, gegeben in einer anderen dieser Größen, bei gleichem Druck und gleicher Temperatur des Gasgemischs. Umrechnung zwischen verschiedenen Zustandsbedingungen bedeutet Berechnung des Werts des Gehalts einer festgelegten Komponente in einer der oben genannten Größen bei einem Satz von Zustandsbedingungen aus dem Wert derselben Größe bei einem anderen Satz von Zustandsbedingungen, d. h. Druck und Temperatur, des Gasgemischs. Durch Kombination dieser beiden Umrechnungsarten kann die Zusammensetzung von Gasgemischen zugleich zwischen verschiedenen Zusammensetzungsgrößen und verschiedenen Zustandsbedingungen umgerechnet werden.
Dieses Dokument ist nur bei homogenen und stabilen Gasgemischen anwendbar. Deshalb müssen die betrachteten Zustandsbedingungen mit deutlichem Abstand außerhalb des Kondensationsgebiets des Gasgemischs liegen. Zusätzlich können Volumenkonzentrationen ausschließlich dann verwendet werden, wenn die betreffende Komponente vollständig gasförmig ist, und bei der Verwendung von Volumenanteilen müssen sogar alle Komponenten vollständig gasförmig sein. Weitere Einschränkungen der Zustandsbedingungen gelten für Näherungen von Realgasfaktoren durch Virialkoeffizienten (siehe Anhang A).
Analyse des gaz - Conversion des données de composition de mélanges gazeux (ISO 14912:2025)
Le présent document définit les grandeurs suivantes qui sont couramment utilisées pour exprimer la composition des mélanges gazeux:
— fraction et concentration molaires;
— fraction et concentration massiques;
— fraction et concentration volumiques.
Pour ces grandeurs de composition, le présent document spécifie des méthodes permettant:
— une conversion entre différentes grandeurs;
— une conversion entre différentes conditions d’état.
La conversion entre différentes grandeurs implique de calculer la valeur de la teneur d’un constituant spécifié, selon les termes de l’une des grandeurs précitées, à partir de la valeur de la même teneur, aux mêmes pression et température du mélange de gaz, exprimée dans une autre de ces grandeurs. La conversion entre différentes conditions d’état implique de calculer la valeur de la teneur d’un constituant spécifié, selon les termes de l’une des grandeurs précitées, dans un ensemble de conditions d’état, à partir de la valeur de la même grandeur dans un autre ensemble de conditions d’état, c’est-à-dire d’autres pression et température, du mélange gazeux. La composition d’un mélange gazeux peut être simultanément convertie entre différentes grandeurs de composition et différentes conditions d’état, en combinant les deux types de conversion.
Le présent document s’applique uniquement aux mélanges gazeux homogènes et stables. Par conséquent, toute condition d’état (pression et température) considérée doit se situer bien en dehors de la région de condensation du mélange gazeux. De plus, les concentrations volumiques ne peuvent être utilisées que si le constituant examiné est entièrement gazeux et, en cas d’utilisation de fractions volumiques, tous les constituants doivent être entièrement gazeux. D’autres restrictions des conditions d’état s’appliquent pour les approximations de facteurs de compressibilité utilisant des coefficients du viriel (voir Annexe A).
Analiza plinov - Pretvorba podatkov o sestavi plinskih zmesi (ISO/FDIS 14912:2025)
General Information
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Standards Content (Sample)
SLOVENSKI STANDARD
oSIST prEN ISO 14912:2023
01-september-2023
Analiza plinov - Pretvorba podatkov o sestavi plinskih zmesi (ISO/DIS 14912:2023)
Gas analysis - Conversion of gas mixture composition data (ISO/DIS 14912:2023)
Gasanalyse - Umrechnung von Zusammensetzungsangaben für Gasgemische (ISO/DIS
14912:2023)
Analyse des gaz - Conversion des données de composition de mélanges gazeux
(ISO/DIS 14912:2023)
Ta slovenski standard je istoveten z: prEN ISO 14912
ICS:
71.040.40 Kemijska analiza Chemical analysis
oSIST prEN ISO 14912:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
oSIST prEN ISO 14912:2023
oSIST prEN ISO 14912:2023
DRAFT INTERNATIONAL STANDARD
ISO/DIS 14912
ISO/TC 158 Secretariat: SAC
Voting begins on: Voting terminates on:
2023-07-31 2023-10-23
Gas analysis — Conversion of gas mixture composition data
Analyse des gaz — Conversion des données de composition de mélanges gazeux
ICS: 71.040.40
This document is circulated as received from the committee secretariat.
THIS DOCUMENT IS A DRAFT CIRCULATED
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ISO/DIS 14912:2023(E)
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PROVIDE SUPPORTING DOCUMENTATION. © ISO 2023
oSIST prEN ISO 14912:2023
ISO/DIS 14912:2023(E)
DRAFT INTERNATIONAL STANDARD
ISO/DIS 14912
ISO/TC 158 Secretariat: SAC
Voting begins on: Voting terminates on:
Gas analysis — Conversion of gas mixture composition data
Analyse des gaz — Conversion des données de composition de mélanges gazeux
ICS: 71.040.40
This document is circulated as received from the committee secretariat.
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
© ISO 2023
ISO/CEN PARALLEL PROCESSING
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NATIONAL REGULATIONS.
Website: www.iso.org ISO/DIS 14912:2023(E)
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PROVIDE SUPPORTING DOCUMENTATION. © ISO 2023
oSIST prEN ISO 14912:2023
ISO/DIS 14912:2023(E)
Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 Quantities for the expression of gas mixture composition . 2
3.2 Additional quantities involved in conversions of gas mixture composition . 3
4 Symbols and units. 4
5 Basic Principles . 5
5.1 Expression of gas mixture composition. 5
5.2 Conversion between different quantities . 7
5.3 Conversion between different state conditions . 9
6 Main procedures . 9
6.1 Conversion between different quantities of composition . 9
6.1.1 Conversion of the content of single components . 9
6.1.2 Conversion of complete compositions . 10
6.2 Conversion to reference conditions . 11
7 Practical implementation.12
7.1 Conversion between quantities of composition .12
7.2 Conversion of single contents . .13
7.3 Conversion of complete compositions . 13
7.4 Conversion between state conditions . 14
7.5 Simple approximations applicable to conversion . 14
7.5.1 Ideal mixture of ideal gases . 14
7.5.2 Ideal mixture of real gases . 14
7.5.3 Trace gas mixture . 15
8 Input quantities and their uncertainties .15
8.1 Pure gas data .15
8.1.1 Molar mass .15
8.1.2 Compression factor . 16
8.2 Gas mixture data . 17
8.2.1 Molar mass . 17
8.2.2 Compression factor . 18
8.2.3 Mixing factor .20
8.3 Rough uncertainty estimates . 21
9 Conversion uncertainty .21
9.1 General considerations. 21
9.2 Conversion of single contents . . 21
9.3 Conversion of complete compositions . 23
9.4 Uncertainty calculation using numerical differentiation. 25
9.5 Variances and covariances of input composition data . 26
9.5.1 General procedure .26
9.5.2 Correlation effects in complete composition data . 26
Annex A (informative) Assessment of state conditions .28
Annex B (informative) Summation relations for the expression of mixture properties .31
Annex C (informative) Mixture component data.32
Annex D (informative) Examples .38
Annex E (informative) Computer implementation of recommended methods.53
iii
oSIST prEN ISO 14912:2023
ISO/DIS 14912:2023(E)
Bibliography .54
iv
oSIST prEN ISO 14912:2023
ISO/DIS 14912:2023(E)
Foreword
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electrotechnical standardization.
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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
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This document was prepared by Technical Committee ISO/TC 158 Analysis of gases.
This second edition cancels and replaces the first edition (ISO 14912:2003 and Cor.1:2006), which has
been technical
...
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