ISO 2496:2006 specifies the following four test methods for the determination of the hygroscopic moisture content of test samples:
Method 1 -- Gravimetric method;
Method 2 -- Karl Fischer volumetric method;
Method 3 -- Karl Fischer coulometric method;
Method 4 -- Mass-loss method.
Any of these methods is applicable wherever the analytical value of a chemical constituent is to be calculated to a dried sample basis in the following ore types.
- Processed ores containing metallic iron (direct reduced iron).
- Natural or processed ores in which the sulfur content is greater than 0,2 % (mass fraction).
- Natural or processed ores in which the combined water is greater than 2,5 % (mass fraction).
Any of these methods is applicable to a concentration range of 0,05 % (mass fraction) to 4,5 % (mass fraction) hygroscopic moisture.