Application of a Modified Low-Field NMR Method on Methane Adsorption of Medium-Rank Coals

Table 6

Comparison of the fits of the Langmuir adsorption parameters by the low-field NMR method and volumetric method.

Sample	ML	ZCD	TL	XQ	XM	DEP	DQ
^a (m^3/t)	19.76	21.64	21.98	21.28	25.64	25.13	32.15
^b (m^3/t)	16.37	19.42	16.61	19.92	21.01	21.19	28.09
^c (m^3/t)	18.90	20.61	21.19	20.49	25.06	25.00	31.85
^a (MPa)	2.69	3.63	2.30	2.82	3.10	2.52	2.37
^b (MPa)	2.35	3.18	1.64	1.93	2.50	2.32	2.20
^c (MPa)	2.36	3.06	2.22	2.72	2.97	2.73	2.65
(m^3/t)	3.39	1.82	5.37	1.36	4.65	3.94	4.06
(m^3/t)	0.86	1.03	0.79	0.79	0.58	0.13	0.30
(%)	17.18	5.79	24.42	6.37	18.07	15.68	12.64
(%)	4.35%	4.76%	3.40%	3.71%	2.31%	0.52%	0.93%

^aThe result based on the volumetric method; ^bthe result based on Yao et al.’s method [49]; ^cthe result based on modified low-field NMR.