Determination of total moisture in coal samples (sample preparation procedure)Coal samples for total moisture determination shall meet the requirements of GB / T 211, and general preparation procedures.
Full moisture coal sample—weigh the air to dry and then weigh—13mm—3kg—6mm—1.25kg—moisture measurement sample.
The actual sample preparation can be adjusted according to specific conditions. When the sample moisture is low and the crushing and shrinking machine is used without substantial bias, it can be crushed to 6mm at a time and then to 1.25kg; when the sample size and particle size are too large, it can also be crushed to 13mm. Add a sample preparation stage. However, the particle size of each stage and the quality of the sample after shrinkage shall meet the requirements of 184.108.40.206.
a) Compare with the moisture measurement value of the coal sample which is not broken. But this method is only applicable to particle sizes below 13mm;
b) Contrast with manual multi-stage sample preparation-determination, that is, air drying to measure the external moisture, and then broken to an appropriate particle size to measure the internal moisture. However, a sealed, small air flow crusher and a splitter should be used for sample preparation.