Page 264 - Advanced Mine Ventilation

Reservoir Properties of Coal Seams 241

Figure 14.9 A hypothetical desorption curve for a low-volatile bituminous coal.

0 1
1
C
B A against [n t will yield a straight line with an
M
Hence, a plot of [n [n @
equation: 1
M N
0 1
1
B C
ln ln B C ¼ 0:9545 ln t 3:0646 (14.22)
M A
@
1
M N
By substituting 1/e for M/M N , we get s ¼ 24.65 days which is comparable with the
result obtained by Eq. (14.20). The value of “n” is 0.9545. Table 14.3 shows the sorp-
2
tion time and (D/a ) values for some US coal seams.