Standard Test Methods for Coal Properties

by Rudy P. SysAdmin at howtofindthemoney

Most, if not all, coals are tested prior to being used. Some markets require specific quality characteristics for the process in which the coal is used, and environmental regulations also require knowledge of a coal’s quality. Some products also require analysis of physical characteristics of coals for handling or processing. Standard tests are prescribed by the American Society for Testing and Materials. ASTM sets standardized procedures for sample preparation and analysis. Certified laboratories for coal analysis in North America follow ASTM procedures, and must regularly check equipment and results by using standard samples and interlaboratory comparative testing. Common coal analyses include:

Ash fusion: determines how coal ash will behave when heated in an industrial furnace or boiler
Ash yield (part of proximate analysis): determines the amount of noncombustible material in a coal sample
Calorific value: determines the heating potential of coal; usually expressed in Btu per pound
Fixed carbon (part of proximate analysis): determines the amount of nonvolatile carbon remaining in a coal sample after combustion
Float-sink (washability) : determines the relative amount of coal that can be separated from attached rock and minerals
Hardgrove grindability: determines how easily coal can be crushed
Major and minor elements by X-ray fluorescence: determines the elemental composition of coal and coal ash
Moisture content: explains tests and equations for different types of moisture content used in coal analysis
Palynology: identifies fossil spores and pollens in coal and shale for correlation and reconstruction of original coal-forming mires
Petrographic analysis: examines microscopic components of coal
Proximate analysis: determines moisture, volatile matter, ash yield, and fixed carbon content in coal
Recording standards terminology: defines as-received, air-dried, etc.
Sulfur forms : determines different types of sulfur in coal
Total carbon (part of ultimate analysis)
Total sulfur (part of ultimate analysis)
Trace element: determines the elemental composition of coal and coal ash
Ultimate analysis: determines amounts of the major elements in coal: carbon, hydrogen, nitrogen, sulfur, oxygen
Vitrinite reflectance (Ro): determines the relative rank of coal
Volatile matter (part of proximate analysis): determines the amount of nonwater gases released by combustion of a sample