吸附气体对突出煤渗流特性的影响

发布时间：2019-06-02 19:35

【摘要】：煤层中瓦斯渗流特性不仅受地应力、煤孔隙结构等因素的影响,还因气体吸附而发生变化。以重庆市万盛区某煤矿突出煤层原煤为实验对象,在有效轴向应力和有效围压为1 MPa条件下,利用自制的三轴渗流试验机研究突出煤吸附二氧化碳、甲烷气体对渗流特性的影响。结果表明:1突出原煤吸附-渗流过程具有明显的阶段特征,煤体变形经历了初始快速变形阶段、缓慢变形发展阶段、变形稳定阶段、收缩变形阶段和渗流稳定阶段;2气体压力越大,煤体膨胀变形越大,相同气体压力下,煤体吸附二氧化碳变形增量大于吸附甲烷变形增量;3随着气体压力的增大,气体渗流速度逐渐增大,呈显著的指数函数关系,突出煤渗透率先减小后增大,具有明显的阶段性。
[Abstract]:The gas seepage characteristics in coal seam are not only affected by ground stress, coal pore structure and other factors, but also change by gas adsorption. Taking the raw coal of a coal mine outburst seam in Wansheng District of Chongqing as the experimental object, the adsorption of carbon dioxide by outburst coal was studied by using a self-made triaxial seepage testing machine under the condition of effective axial stress and effective confining pressure of 1 MPa. Effect of methane gas on seepage characteristics. The results show that: (1) the adsorption-seepage process of outburst raw coal has obvious stage characteristics, and the deformation of coal body has gone through the initial rapid deformation stage, the slow deformation development stage, the deformation stability stage, the shrinkage deformation stage and the seepage stability stage; (2) the higher the gas pressure is, the greater the expansion and deformation of coal body is. Under the same gas pressure, the deformation increment of carbon dioxide adsorption of coal body is larger than that of adsorbed methane. (3) with the increase of gas pressure, the gas seepage velocity increases gradually, showing a significant exponential function relationship. The infiltration of outburst coal decreases at first and then increases, which has obvious stages.
【作者单位】：重庆大学煤矿灾害动力学与控制国家重点实验室;
【基金】：高等学校博士学科点专项科研基金资助项目(20130191130003) 中央高校基本科研业务费资助项目(CDJXS12241104) 重庆市研究生科研创新项目资助项目
【分类号】：TD713

【参考文献】