CCC/212 ISBN 978-92-9029-532-7

December 2012

copyright © IEA Clean Coal Centre

Abstract

This report examines the way coal can change as it passes along the coal chain. A great deal of the

change is intended, through separation and sizing, to ensure the coal being mined matches the

specification demanded by the customer. This report attempts to identify these changes and presents

some of the issues faced by the coal supplier and user. Much of the change leads to a loss of mass in

the coal. Some of the coal is left in the ground (intentionally and unintentionally), while elsewhere,

full extraction might occur with the addition of non-coal materials from the surrounding rocks. In both

cases, the mined coal often requires further processing.

Coal processing by separation at preparation plants refines coal further and is where most of the mass

loss occurs. Value is added by reducing ash content and improving heating value, thus providing a

much more saleable product for the market. As soon as the coal leaves the mine, mass loss can occur

either through natural deterioration of the fuel, through spillage or dust, or in extreme cases theft. In

all cases measuring the amount of coal as it passes through the supply chain is required to verify that

the coal reaching the consumer is of satisfactory quality and quantity. This can be done crudely by

measuring stockpiles, to more sophisticated weighing systems at various points along the supply

chain, and even measuring the volume held in a ship. Measurement is subject to error which must be

minimised. Biomass needs to be processed in much the same way as coal, such as removing mineral

matter and taking care in avoiding contamination.