ISO 20676:2018 天然ガス—上流域—レーザー吸収分光法による硫化水素含有量の測定 | ページ 2

Foreword

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This document was prepared by Technical Committee ISO/TC 193, Natural gas, Subcommittee SC 3, Upstream area.

Introduction

Four methods for determination of sulfur compounds in natural gas already exist as International Standards:

• 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 16960, Natural gas — Determination of sulfur compounds — Determination of total sulfur by oxidative microcoulometry method;
• ISO 19739, Natural gas — Determination of sulfur compounds using gas chromatography;
• ISO 20729, Natural gas — Determination of sulfur compounds — Determination of total sulfur content by ultraviolet fluorescence method.

Laser absorption spectroscopy is a more efficient method compared with chemical titration because it is an optical and instrumental method. It offers a more convenient and more stable means to analyse H₂S in upstream area natural gas.

1 Scope

This document specifies a method for the determination of hydrogen sulfide content in working field natural gas of upstream area by laser absorption spectroscopy. The analytical range expressed as mole fraction is 10 × 10⁻⁶ to 20 %. The analytical range can be expanded to higher content with specific instrument requirements.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

3 Terms and definitions

No terms and definitions are listed in this document.

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Bibliography