ISO/AWI 22813

Natural gas — Determination of composition of Liquefied Natural Gas and associated uncertainty by Raman Spectroscopy

Apstrakt

This document describes a method for determination of the mole fractions of C1 to C5 hydrocarbons and nitrogen in LNG. Procedures for the calculation of the uncertainty of the mole fractions obtained are also given.
The results can be used as input for the calculation of natural gas properties, such as caloric value, (relative) density and/or Wobbe indices.
Requirements for installation, calibration and validation of the analyser are specified.
This document also gives guidance on performance evaluation of a Raman analyser system and typical performance limits expected in LNG custody transfer.