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

Table 4

Results of constant temperature adsorption experiment of the coal sample.

Coal mine	Mark as	Adsorption constants a	Adsorption constants b	Fitting curve	R^2
Lvtang	LT-1	18.7513	2.6515	Q = 49.7169P/(1 + 2.6515P)	0.9991
	LT-2	18.5424	2.5425	Q = 47.1457P/(1 + 2.5427P)	0.9992
Quanlun	QL-1	18.1	0.44	Q＝7.74P/(1 + 0.35P)

The adsorption constants a and adsorption constants b are important indicators of the ability of coal to absorb gas, which conform to the Langmuir adsorption formula: . Here, a is the value reflects the maximum adsorption capacity of the coal, cm³/g; b is the value represents the rate at which the coal reaches its saturated adsorption capacity, MPa⁻¹; Q is gas adsorption capacity under a certain pressure, cm³; P is the gas pressure of the coal seam, MPa.