GB/T 25214-2010Determination of total sulfur in coal by IR spectrometry (English PDF)

Foreword

This Standard modifies and uses ISO 19579:2006, Solid mineral fuels -

Determination of sulfur by IR spectrometry.

This Standard is redrafted in accordance with ISO 19579: 2006. Appendix A

lists a comparison list of chapter numbers of this Standard and chapter numbers

of ISO 19579: 2006.

In consideration of China's national conditions, while adopting ISO 19579: 2006,

this Standard makes some modifications. Relevant technical differences have

been incorporated into the text and are marked with a single vertical line in the

margins of the articles to which they relate. Appendix B provides a list of these

technical differences and their causes for reference.

The main technical differences between this Standard and ISO 19579: 2006

are as follows:

-- Use 1300 °C instead of 1350 °C as the sample combustion temperature;

-- Add the schematic diagram of instruments and apparatus and the

description of the composition system;

-- Use about 0.3 g instead of (0.2 ~ 0.5) g as the weighing sample;

-- Combine the calibration content and calibration check in the step into a

separate clause; add detailed calibration step requirements;

-- Determine the method precision according to domestic collaborative

experiments in China; give it in stages according to the range of total sulfur

content.

For convenience of use, this Standard also makes the following editorial

changes:

-- Change "this International Standard" into "this Standard";

-- Use the decimal point "." to replace the comma ",";

-- Delete the foreword and introduction of ISO 19579: 2006.

Appendix A and Appendix B of this Standard are informative appendixes.

This Standard was proposed by China National Coal Association.

This Standard shall be under the jurisdiction of National Technical Committee

42 on Coal of Standardization Administration of China (SAC/TC 42).

Determination of total sulfur in coal by IR

spectrometry

1 Scope

This Standard specifies the method summary, reagents and materials,

instruments and apparatus, determination, calibration, and method precision for

the determination of total sulfur in coal by high-temperature combustion IR

spectroscopy.

This Standard applies to lignite, soft coal, hard coal, and cokes.

2 Normative references

The terms in the following documents become the terms of this Standard by

reference to this Standard. For dated references, all subsequent amendments

(not including errata content) or revisions do not apply to this standard. However,

parties to agreements that are based on this Standard are encouraged to study

whether the latest versions of these documents can be used. For undated

references, the latest edition applies to this Standard.

GB/T 212, Proximate analysis of coal (GB/T 212-2008, ISO 11722:1999,

Solid mineral fuels - Hard coal - Determination of moisture in the general

analysis test sample by drying in nitrogen; ISO 1171:1997, Solid mineral

fuels - Determination of ash; ISO 562:1998, Hard coal and coke -

Determination of volatile matter, NEQ)

GB/T 483, General rules for analytical and testing methods of coal (GB/T

483-2007, ISO 1213:1992, Solid mineral fuels - Vocabulary - Part 2: Terms

relating to sampling, testing and analysis, NEQ)

3 Method summary

The coal sample is combusted and decomposed at 1 300 °C in a stream of

oxygen. Particles and water vapor are removed from the gas stream by traps

of glass wool and magnesium perchlorate. The gas stream then passes through

a cell in which the sulfur dioxide is measured by an infrared absorption detector.

Use standard reference materials to calibrate the instrument. The percentage

of sulfur in the sample is calculated from this prior calibration by the

microprocessor.

8 Result expression

The total sulfur content of the tested samples (in terms of mass fraction, %) is

reported, to 0.01% according to GB/T 483, as the average value of the repeated

measurement results.

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