PD ISO TR 22302-2014 PDF

Full title and description

STB PD ISO TR 22302:2014 — Natural gas — Calculation of methane number. This technical report provides composition‑based methods to calculate the methane number (MN) of dry natural gas from its mole‑fraction composition and guidance on interpretation and limits of those calculation methods.

Abstract

ISO/TR 22302:2014 describes calculation procedures used to estimate the methane number (a measure of knock resistance) of dry natural gas when the gas composition (mole fractions of constituents) is known. The report summarises commonly used algorithms, highlights differences between methods, notes limits of applicability (including treatment of inerts such as N2 and CO2), and recommends laboratory testing when calculated values differ beyond acceptable tolerances.

General information

• Status: Withdrawn (originally published 2014).
• Publication date: July 2014 (Edition 1, 2014).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 75.060 — Natural gas.
• Edition / version: Edition 1, ISO/TR 22302:2014.
• Number of pages: 11 (ISO published length; national/adopted PDF variants may show different page counts due to formatting).

Scope

This technical report applies to dry natural gas and provides methods to calculate the methane number (MN) from known mole‑fraction gas composition. It is intended to support fuel quality assessment for spark‑ignition and dual‑fuel engines and to inform interchangeability and engine compatibility evaluations. The report clarifies the ranges and assumptions for each calculation method and recommends experimental testing when calculation methods yield substantially different MN values.

Key topics and requirements

• Definition and purpose of the methane number (MN) as an index of knock resistance for gaseous fuels.
• Composition‑based calculation methods for MN (including commonly used industry algorithms derived from MON correlations and proprietary/industry methods).
• Use of motor octane number (MON) correlations as an intermediate step in some MN calculations.
• Treatment and influence of inert components (nitrogen, carbon dioxide) and higher hydrocarbons on MN calculations.
• Application limits and recommended compositional ranges for reliable calculation results.
• Guidance that if two calculation methods differ by more than a specified tolerance (industry practice: about 6 MN units), a test (measured MN) is recommended.
• Informative examples and notes on interpretation for engine manufacturers, gas suppliers and laboratories.

Typical use and users

Typical users include natural gas producers, transmission and distribution companies, CNG/LNG fuel suppliers, engine and vehicle manufacturers, test laboratories, regulators and standards bodies. The technical report is used to estimate fuel suitability for spark‑ignition and dual‑fuel engines, to support fuel specification development and to provide input to interchangeability and quality control procedures.

Related standards

Standards and documents commonly referenced alongside ISO/TR 22302 include international and industry standards for gas composition and properties (for example, ISO 6976 — calculation of calorific values, density and Wobbe indices; the ISO 6974 series — gas composition determination; and natural gas vehicle/fuel quality standards). National/adopted publications and manufacturer guidance on methane number calculation (and laboratory test methods) are also relevant.

Keywords

methane number; MN; knock resistance; motor octane number (MON); natural gas composition; gas quality; CNG; LNG; calculation methods; gas interchangeability; fuel specification; ISO/TR 22302:2014.

FAQ

Q: What is this standard?

A: ISO/TR 22302:2014 is a technical report titled "Natural gas — Calculation of methane number" that describes methods for calculating the methane number of dry natural gas from its composition. It is a guidance report rather than a mandatory specification.

Q: What does it cover?

A: It covers composition‑based calculation procedures for methane number, related assumptions and limits of applicability, treatment of inert and higher hydrocarbon components, and recommendations on when laboratory measurement is preferable (for example, when different calculation methods disagree beyond established tolerances).

Q: Who typically uses it?

A: Gas industry technical staff, fuel suppliers, engine and vehicle manufacturers, test laboratories, regulators and standards developers use it to assess fuel compatibility with engines, to inform fuel quality specifications and to support interchangeability assessments.

Q: Is it current or superseded?

A: The ISO record shows ISO/TR 22302:2014 as published in 2014 and later withdrawn. Users should check the latest ISO catalogue or national standards body for current guidance and any successor documents or updated methods before relying on the withdrawn report for regulatory or contractual purposes.

Q: Is it part of a series?

A: ISO/TR 22302:2014 sits within the broader set of natural gas standards (ICS 75.060) that address composition, properties and fuel quality (for example, standards for composition determination and calculation of calorific values). It is a standalone technical report focused on methane‑number calculation but is commonly used alongside related ISO standards on gas composition and properties.

Q: What are the key keywords?

A: Methane number, MN, motor octane number, MON, natural gas quality, CNG, LNG, gas composition, knock resistance, calculation methods.