Experimental Study and Microscopic Mechanism of Effects on Coal-seam Gas Absorption by Water

摘要

In order to study on the differences of existing state of coal-seam gas in the same stratum and different water content phases, coking coal samples from XI SHAN TUN LAN Mine have been chosen and a series of experimental equipments for fixed volume absorption have also been designed. Further dealing with the researches of absorption velocities, capacities or microscopic mechanism, eight different water contents of cylinder lump coal samples have been adopted separately to engage in the typical experiments of coal-seam gas absorption. From the absorbability experiments, the existing state of coal-seam gas in the stratum has been explained. Experimental results indicate that: 1) at the same initial absorption pressure, the absorption velocities are decreased with the increasing of water contents. And the absorption amount of water content 0% is 22 times than the water content 2%. 2) The simulation result of absorption capacities of coalseam gas followed by water content is linear. 3) At the different water contents, the law of absorption capacities followed by time is logarithmic and would not be getting to steady estate until undergoing 12 hours or even more. The results which are stood for the simulative equations are different whether the water content beyond 1% or not. 4) By ways of the analyses for the researches on absorptive microscopic mechanism between gas and water, the absorbability of coal-seam gas by water is related to the fractures distribution on the surface of coal samples.