不同变质煤的瓦斯解吸粒级效应及规律

Effect of particle size on methane desorption from different metamorphic coal samples

为揭示粒级对煤层瓦斯（甲烷）解吸特性的影响,开展物理模拟试验,研究无烟煤（高变质）和长焰煤（低变质）柱状煤样和颗粒煤样在不同吸附压力下瓦斯解吸量和解吸速率方面的差异。结果表明：甲烷自煤样整个解吸过程中,煤样变质程度与累计瓦斯解吸量、解吸速率整体正相关,粒煤的累计瓦斯解吸量始终大于柱煤,两者之差先增大后减小;相同变质程度等压力下,累计瓦斯解吸量、解吸速率表现出明显的粒级效应;0.5-1 mm与1-3 mm煤样粒级,在解吸量上即将到达极限粒度。

In order to reveal the effect of particle size on gas methane desorption from coal seam,physical simulation experiments were carried out the difference of gas desorption capacity and desorption.Differences between the cylindrical coal sample and the granular coal sample of anthracite（high metamorphic） coal and those of long flame coal（low metamorphic） in the effects on the gas desorption amount and the desorption rate were studied under different adsorption pressure conditions. The results show that there is a positive correlation between both the cumulative gas desorption amount and the desorption rate and the coal ＇ s metamorphism in the whole desorption process,that the cumulative gas desorption amount from granular coal is always greater than that from column coal,and the difference between the two increases first and then decreases,that particle size has an obvious effect on both the cumulative gas desorption amount and the desorption rate under the same metamorphic degree and pressure,and that the two granular coal sample grades of 0.5-1 mm and 1-3 mm are about to reach the limit of granularity in the desorption amount.