ABSTRACT

Through the reasonable design of experimental instrument, the experimental mechanism of adsorption-diffusion of thin sliced coal samples is explored, and a set of rigorous experimental procedures, data acquisition, and processing methods are formed. The method is to grind coal samples into rectangular samples with thickness less than 4 mm and place them in a sealed container. The adsorption and diffusion characteristics of the coal matrix are accurately reflected due to its original internal structure. The three-dimensional diffusion model of the Fick’s second law is simplified to one-dimensional diffusion model, and the diffusion coefficient is calculated. The accuracy of experimental parameters is improved by the instrument combination of sample diffusion test cylinder, pressure reference cylinder and differential pressure gauge. Meanwhile, a set of calculation methods for the adsorption amount and diffusion coefficient of coal slice is proposed. The experimental results indicate that the diffusion coefficient of coal matrix is sensitive to temperature and diffusion path, but insensitive to pressure and fixed carbon content of coal matrix. The adsorption amount is sensitive to the change of fixed carbon content. Meanwhile, the experimental results of different coal samples are basically consistent with the characteristics of the production wells in the mine.

摘要

通过合理设计实验仪器，探索了薄片煤样品吸附扩散的实验机理，形成了一套严格的实验程序，数据采集和处理方法。该方法是将煤样品研磨成厚度小于4毫米的矩形样品，然后将它们放在密封的容器中。由于其原始的内部结构，因此可以准确反映出煤基质的吸附和扩散特性。将菲克第二定律的三维扩散模型简化为一维扩散模型，并计算了扩散系数。通过将样品扩散测试筒，压力基准筒和压差计组合使用，可以提高实验参数的准确性。与此同时，提出了一套煤片吸附量和扩散系数的计算方法。实验结果表明，煤基质的扩散系数对温度和扩散路径敏感，而对煤基质的压力和固定碳含量不敏感。吸附量对固定碳含量的变化敏感。同时，不同煤样的实验结果与矿井生产井的特征基本吻合。吸附量对固定碳含量的变化敏感。同时，不同煤样的实验结果与矿井生产井的特征基本吻合。吸附量对固定碳含量的变化敏感。同时，不同煤样的实验结果与矿井生产井的特征基本吻合。