ASTM D388-2018 pdf free download

ASTM D388-2018 pdf free download.Standard Classification of Coals by Rank
1. Scope
1.1 This standard covers the classification of coals by rank, that is, according to their degree of metamorphism, or progres- sive alteration, in the natural series from lignite to anthracite. 1.2 This classification is applicable to coals that are com- posed mainly of vitrinite. N OTE 1—Coals rich in inertinite or liptinite (exinite), or both, cannot be properly classified because, in those macerals, the properties that deter- mine rank (calorific value, volatile matter, and agglomerating character) differ greatly from those ofvitrinite in the same coal. Often such coals can be recognized by megascopic examination. In North America, these coals are mostly nonbanded varieties that contain only a small proportion of vitrain and consist mainly of attrital materials. The degree of metamor- phism of nonbanded and other vitrinite-poor coals can be estimated by determining the classification properties of isolated or concentrated vitrinite fractions, or by determining the reflectance of the vitrinite (see Test Method D2798 and Appendix X1 of this classification). However, in the use of these vitrinite-poor coals, some properties normally associated with rank, such as rheology, combustibility, hardness, and grindability (as well as the rank determining properties) may differ substantially from those of vitrinite-rich coals of the same degree of metamorphism. The precision of the classification of impure coal may be impaired by the effect of large amounts of mineral matter on the determination of volatile matter and calorific value, and on their calculation to the mineral-matter-free basis. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. The values given in parentheses are for information only. 1.3.1 Exception—The values stated in British thermal units per pound (Btu/lb) are to be regarded as the standard. The SI equivalents ofBtu/lb 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 appro- priate safety, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use. 1.5 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
6. Classification by Rank
6.1 FixedCarbon andGross Calorific Value—Coals shall be classified by rank in accordance with Table 1. Classify coals having gross calorific values of 14 000 Btu/lb or more on the inherent-moisture, mineral-matter-free basis, and coals having fixed carbon of 69 % or more on the dry, mineral-matter-free basis, according to fixed carbon on the dry, mineral-matter-free basis. Classify coals having gross calorific values less than 14 000 Btu/lb on the inherent-moisture, mineral-matter-free basis according to gross calorific value on the inherent- moisture, mineral-matter-free basis, provided the fixed carbon on the dry, mineral-matter-free basis is less than 69 %. 6.2 Agglomerating Character—Classify coals having 86 % or more fixed carbon on the dry, mineral-matter-free basis, if agglomerating, in the low volatile group of the bituminous class. Classify coals having gross calorific values in the range from 10 500 to 11 500 Btu/lb on the inherent-moisture, mineral-matter-free basis according to their agglomerating character (Table 1).
7. Sampling
7.1 Samples—Classify a coal seam, or part of a coal seam, in any locality based on the average analysis and gross calorific value (and agglomerating character where required) of not less than three and preferably five or more whole seam samples, either face channels or cores, taken in different and uniformly distributed localities, either within the same mine or closely adjacent mines representing a continuous and compact area not greater than approximately 10 km 2 (4 square miles) in regions of geological uniformity. In regions in which conditions indicate that the coal probably varies rapidly in short distances, the spacing of sampling points and grouping of analyses to provide average values shall not be such that coals ofobviously different rank will be used in calculating average values. 7.1.1 Take channel samples by excluding mineral partings more than 1 cm ( 3 ⁄ 8 in.) and lenses or concretions (such as sulfur balls) more than 1.25 cm ( 1 ⁄ 2 in.) thick and 5 cm (2 in.) wide, as specified in Practice D4596.