【作者】 张法智；

【导师】 李小春；

【作者基本信息】 中国科学院研究生院（武汉岩土力学研究所） ， 岩土工程， 2008， 硕士

【摘要】 煤层气俗称瓦斯,是煤的生成过程中伴生的一种气体,主要成分是甲烷。提高瓦斯抽取率,具有防治瓦斯突出、改善能源结构和温室气体减排三重功效。目前瓦斯抽采面临的一个大问题,在于空气沿煤壁裂隙混入抽采孔,致使抽采率比较低。本文开发了一种名为LIT密封剂的岩土粘结材料,将其喷涂于煤壁,可堵塞煤壁的裂隙,并在表层形成一层致密的薄膜,大幅度提高瓦斯抽采率。此外,巷道开挖过程中,瓦斯大量沿煤壁裂隙涌出,巷道内瓦斯超限。将LIT密封剂喷涂于开挖巷道的煤壁,可以减缓瓦斯涌出。主要内容如下:第一章为绪论,着重介绍了煤层气开发的意义,根据现有的瓦斯抽采方法,提出了喷涂法;第二章为LIT密封剂的提出。通过对巷道壁面特点的研究,提出了开发一种新型岩土粘接材料来提高瓦斯抽取率的目的;第三章为LIT密封剂的室内试验研究。研究了LIT密封剂的密封性施工性、时效性、经济性、安全性、不可燃性、无腐蚀性等多方面因素,并证明了LIT密封剂对钢铁防锈和调节水泥固化时间有作用:第四章为喷涂封孔与井下平行孔驱替煤层气技术试验。试验证明,LIT密封剂提高瓦斯抽取率的效果良好,而且成本低,施工性好;第五章为LIT密封剂巷道喷涂减缓瓦斯涌出试验研究:针对巷道开挖过程中,瓦斯涌出量大、巷道内瓦斯含量时常超限的特点,进行了LIT密封剂巷道喷涂减缓瓦斯涌出试验的研究。试验证明,LIT密封剂治理瓦斯超限有良好的作用;第六章得出LIT密封剂可用于巷道壁面密封以提高瓦斯抽采率,并可以抑制掘进巷道瓦斯涌出的结论,以及展望了下一步的研究内容。提出了LIT密封剂在其他方面的应用,并提出了下一步研究的方向。更多还原

【Abstract】 Coalbed gas was generated with coal, and its main ingredient is CH₄. Recovering a higher proportion of the deposited gas before coal mining is an effective way to prevent gasbrusts, reduce metane emission and enhance the mining efficiency. One of the key reasons why most of coal mines have a coalbed gas recovery lower than 20% is the poor sealing of the production wells. Traditional sealing techniques have focused on sealing of the wells itself, the effect of which has been proven poor by practical experiences. In fact, sealing the cracks surrounding the well should be as important as sealing the well itself. Based on this point, the author has developed a glue, named LIT. The cracks are sealed by spraying the glue onto the walls of a coal tunnel. The glue can be solidified when contacting air, formed into membrane-like materials, prevent air from entering the coalbed, help to maintain a higher suction pressure in the well, and eventually enhance the gas recovery ratio. The more the gas is produced and transported to surface via a piprline, the lower the methane concentration of the ventilation air in the tunnel will be. The purpose of this study is to develop the materials, apparatuses and procedures suitable for coal tunnel sealing..Chapter 1 describes the relevant background.Chapter 2 presents a brief description of the tun nel sealing method.Chapter 3 is about the laboratory experimental research on LIT glue. The results showed that the glue is suitable for the tunnel sealing.Chapter 4 goes to tunnel sealing tests in a coal mine. The walls of q 200m long tunnel was covered with LIT, and the gas production processes, before and after the sealing, was monitored. The results showed that the sealing has a remarkable role in enhance the gas production rate and concentration.Chapter 5 discusses the role of the sealing in reducing the methane concentration in tunnel ventilation air.Chapter 6 outlines major conclusions and the further work.更多还原