NMR成像技术测试煤样渗吸过程中水分变化规律研究

外加水在渗吸过程中可以促进煤体瓦斯解吸，减小煤层瓦斯含量，从而减少瓦斯事故的发生频率。为了研究含瓦斯煤水分分布规律，采用NMR（核磁共振成像）技术，针对不含瓦斯煤进行定量外加水渗吸实验。研究结果表明:型煤中的水分主要受毛细管力和重力作用的影响；在自下向上吸水和自上向下吸水渗吸过程中，毛细管力作用相同，径向方向上水分扩散速度相近，但在轴向方向上的扩散速度具有明显差异，由于重力作用的影响，分别产生抑制和促进作用；水分三向扩散半径与时间符合朗格缪尔函数关系。

Study on change laws of moisture during imbibition process of coal samples tested by NMR imaging technology

The added water can promote the desorption of coal gas in the process of imbibition, reduce the gas content of coal seam, and thus reduce the frequency of gas accidents. In order to study the moisture distribution laws of coal containing gas, the quantitative water adding imbibition experiments were carried out on the gas free coal by using the NMR (nuclear magnetic resonance) imaging technology. The results showed that the moisture in the briquette was mainly affected by the capillary force and gravity. In the imbibition processes of bottom up water absorption and top down water absorption, the effect of capillary force were the same, and the moisture diffusion velocities in the radial direction were similar, but the diffusion velocities in the axial direction were significantly different. Due to the influence of gravity, the inhibition and promotion effect were generated respectively. The relationship of the three direction (X, Y and Z) diffusion radius of the moisture with time was in accordance with the Langmuir function.