Study on the Effect of Soft and Hard Coal Pore Structure on Gas Adsorption Characteristics

Table 1

Experiment and proximate analysis data of coal samples.

Coal type	Coal mine	Mark as	Mad	Aad	Vdaf	f
Soft coal	Lvtang	LT-1	0.73	10.98	12.1	0.1912	19.8
		LT-2	0.83	12.1	15.1	0.1622	20.6
Hard coal	Quanlun	QL-1	6.54	7.24	36.11	0.6742	11.4
		QL-2	5.98	6.65	35.25	0.6982	13.8

Mad is moisture content on air-dry (ad) basis, %; Aad is ash content on air-dry (ad) basis, %; Vdaf is volatile matter content on dry-ash-free (daf) basis, %; f is coal hardiness coefficient, dimensionless; is the initial gas diffusion velocity of coal, mmHg.