【国外标准】 Standard Test Method for Determining the Relative Degree of Oxidation in Bituminous Coal by Alkali Extraction

5.1 This test method is a relative measure of the degree of oxidation present in coal. It does not determine the quantitative amount of oxidized coal present. It is only intended to serve as a guide to the supplier, buyer, and user for selecting coals for metallurgical use.NOTE 1: Lower rank bituminous coals are more easily extracted than higher rank coal.1.1 This colorimetric test method describes the determination of the relative degree of oxidation by alkali extraction of coals that are high volatile A bituminous to low volatile bituminous in rank.1.2 This test cannot be sensitive to thermally oxidized coal. It is intended for coals that may be oxidized as a result of weathering.1.3 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.