水分对阜康矿区低阶煤瓦斯放散特性影响的实验研究

发布时间：2018-06-04 00:39

本文选题：低阶煤 + 水分　；参考：《西安科技大学》2017年硕士论文

【摘要】：新疆煤层气赋存具有煤层厚度大、煤层层数多、煤阶低、煤层气含量较低、渗透率大、丰度大等特点。随着新疆煤炭开发力度逐渐增大,煤矿灾害频发,尤其是瓦斯灾害严重威胁新疆煤矿企业的安全生产。水分作为煤矿井下的常见物质之一,对于煤层中的瓦斯吸附—解吸具有十分重要的作用,因此有必要研究水分对新疆阜康矿区低阶煤瓦斯放散特性,利用其规律及特性,达到安全生产目的。选取五种阜康矿区低阶煤,展开相关基础性实验:利用氮吸附法对煤样进行孔隙结构的测定实验,得到煤样的孔隙结构差异较大,各个煤样间无明显规律;通过煤样自发吸水性实验,得到吸水性以屯堡煤样最好,最差为艾维尔沟2130煤样;润湿性以屯堡煤样最好,艾维尔沟2130煤样最差。最终选取艾维尔沟2130煤样和屯堡煤样两种差异较大的典型煤样进行水分对煤样瓦斯放散特性影响实验。利用自主研发的煤样瓦斯放散特性测定实验装置,进行水分对阜康矿区低阶煤瓦斯放散特性的实验研究。实验结果表明:水分进入煤体后会置换出煤体内部原本吸附的瓦斯气体,一方面使得煤体的吸附量减小,导致煤体的放散量减小,另一方面形成“毛细管”现象,堵塞煤体内的瓦斯放散通道,导致煤体的放散速率减小;且随着注水量的增加,煤体的放散量和放散速率均减小,最终放散完成后,两者都趋于一个定值。水分对不同变质程度和不同亲水性煤样的影响程度不同。水分对屯堡煤样瓦斯放散量、放散速率以及解吸率的影响程度始终大于对艾维尔沟煤样的影响程度。由于实验中所有的解吸过程均为过渡型扩散,由于无法确定其具体形式,因此本论文采用数据拟合的方法进行煤样瓦斯放散特性的定量计算。最终确定了两个拟合度较高的通式作为低阶煤瓦斯放散特性的计算公式。
[Abstract]:The occurrence of coal bed methane in Xinjiang is characterized by large thickness of coal seam, more layers of coal seam, low rank of coal bed, low content of coal bed gas, large permeability and large abundance. With the increasing intensity of coal exploitation in Xinjiang, coal mine disasters occur frequently, especially the gas disasters seriously threaten the safety production of coal mining enterprises in Xinjiang. As one of the common substances in coal mine, moisture plays a very important role in gas adsorption-desorption in coal seam. Therefore, it is necessary to study the characteristics of low-rank coal gas release by water in Fukang mining area, Xinjiang, and make use of its law and characteristics. To achieve the goal of production safety. Five kinds of low-rank coal in Fukang mining area were selected and related basic experiments were carried out: the pore structure of coal samples was measured by nitrogen adsorption method, and the difference of pore structure of coal samples was large, and there was no obvious regularity among coal samples. Through the spontaneous water absorption experiment of coal sample, Tunpu coal sample is the best and the worst coal sample is Evelle gully 2130 coal sample, and the wettability is the best in Tunpu coal sample and the worst in Erville ditch 2130 coal sample. Finally, two typical coal samples, Evelogou 2130 coal sample and Tunpu coal sample, were selected to test the effect of water content on the gas emission characteristics of coal sample. In this paper, the characteristics of low-rank coal gas emission in Fukang mining area were studied by using the self-developed experimental device for measuring the gas emission characteristics of coal samples. The experimental results show that when moisture enters the coal body, it will replace the gas originally adsorbed inside the coal body. On the one hand, the adsorption amount of the coal body will be reduced, which will lead to the decrease of the coal mass emission amount, on the other hand, the phenomenon of "capillary" will be formed. Blocking the gas release channel in the coal body leads to the decrease of the coal mass emission rate, and with the increase of the water injection rate, both the coal mass emission rate and the emission rate decrease, and after the final release is completed, both of them tend to a fixed value. The effect of moisture on different metamorphic and hydrophilic coal samples is different. The influence of moisture on gas release rate and desorption rate of Tunpu coal sample was always greater than that on coal sample in Erville ditch. Because all the desorption processes in the experiment are transitional diffusion and its specific form can not be determined, this paper uses the method of data fitting to quantitatively calculate the gas emission characteristics of coal samples. Finally, two general formulas with high fitting degree are determined as the calculation formulas of gas emission characteristics of low rank coal.
【学位授予单位】：西安科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD712

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