This standard specifies nitrogen-filling atmospheric pressure method for determination of the moisture-holding capacity in coal, including the method summary, reagents and materials, instruments and apparatus, preparation of coal sample, determination procedures, expression of results and method precision.
This standard is applicable to lignite, bituminite and anthracite.
2 Normative References
The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments (excluding corrections), or revisions, of any of these publications do not apply to this standard. However parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies.
GB/T 212 Proximate Analysis of Coal (GB/T 212-2008, ISO 11722: 1999, ISO 1171: 1997, ISO 562: 1998, NEQ)
GB 474 Method for Preparation of Coal Sample (GB 474-2008, ISO 18283: 2006, Hard Coal and Coke - Manual Sampling, MOD)
GB/T 483 General Rules for Analytical and Testing Methods of Coal
GB/T 6003.1 Test Sieves of Metal Wire Cloth
GB/T 16496 Chemical Reagent - Potassium Sulfate
3 Method Summary
After the coal sample reaches water saturation, remove most of external moisture with constant-humidity paper, the coal is brought to moisture equilibrium with an nitrogen-filling atmospheric pressure, relative humidity of 96% at 30℃ and then dried under nitrogen flow at 105~110℃. The moisture-holding capacity is expressed by the fraction of mass loss.
4 Reagents and Materials
4.1 Pulp mixing potassium sulfate crystal with its saturated solution: add 10g chemically pure potassium sulfate (GB/T 16496) to 3mL water to form a pulp.
