What’s the meaning of "As received basis", "Air dried basis" , "Dry basis and Dry ash-free basis"?
1. As received basis: Coal in the condition as received by the consumer or the laboratory analyzing the coal. (This kind of coal includes all contents: Organic constituent, inorganic constituent (Inherent moisture, free moisture). Use the coal as received basis to represent coal content)
2. Air dried basis: The coal has naturally dried in the open air until it cannot dry or dissipate any more moisture. Use the coal in air dried basis to represent coal content.
3. Dry basis: An analysis expressed on the basis of a coal sample from which the total moisture has in theory been removed. Coal in dry basis includes all contents but moisture. Use the coal in dry basis to represent coal content.
4. Dry ash-free basis: An analysis expressed on the basis of a coal sample from which the total moisture and the ash have in theory been removed. Use the coal in air dried basis to represent coal content.