Liu Jiajia, Hu Jianmin, Huang Xuchao, Yu Baozhong, Nie Zishuo, Yang Di
School of Safety Science and Engineering, Henan Polytechnic University, Jiaozuo, Henan 454003, China.
State Key Laboratory of Gas Disaster Detecting, Preventing and Emergency Controlling, Chongqing 400037, China.
ACS Omega. 2022 May 23;7(22):18752-18760. doi: 10.1021/acsomega.2c01478. eCollection 2022 Jun 7.
In order to deeply study the influence of the coal bedding structure on coal gas adsorption, low nuclear magnetic resonance (LNMR) and a confining pressure loading system were used to carry out the LNMR experiment of gas adsorption of high-rank coals with different beddings under different confining pressures. The results showed that the amount of gas adsorption of high-rank coals with different beddings increases with time and decreases with the increase of confining pressure. In the process from low confining pressure to high confining pressure, the coal sample with oblique bedding (bedding angles 30°, 45°, and 60°) has the largest average increment of gas adsorption, followed by the coal sample with vertical bedding (bedding angle 90°), and the coal sample with parallel bedding has the smallest increment of gas adsorption (bedding angle 0°). The linear function relation between the different-bedding high-rank coal gas adsorption state and the confining pressure is = - . The relation between the free peak area and the confining pressure conforms to the exponential function = + exp(). Different-bedding high-rank coal adsorption peaks and the peak area decrease with the increase of confining pressure, and the free peak continues to move to the left; that is, the large pores gradually shrink. With the increase of angle and bedding, the area of the adsorption peak increases first and then decreases, presenting an "inverted V" shape on the whole. The area of the free peak decreases first and then increases, presenting a "V" shape on the whole.
为深入研究煤层结构对煤气吸附的影响，采用低场核磁共振（LNMR）和围压加载系统，对不同层理的高阶煤在不同围压下进行煤气吸附的LNMR实验。结果表明，不同层理的高阶煤的煤气吸附量随时间增加而增加，随围压升高而降低。在从低围压到高围压的过程中，斜层理（层理角度30°、45°和60°）的煤样煤气吸附平均增量最大，其次是垂直层理（层理角度90°）的煤样，平行层理（层理角度0°）的煤样煤气吸附增量最小。不同层理高阶煤煤气吸附状态与围压之间的线性函数关系为 = - 。自由峰面积与围压之间的关系符合指数函数 = + exp()。不同层理高阶煤的吸附峰和峰面积随围压升高而减小，自由峰不断向左移动，即大孔隙逐渐收缩。随着层理角度的增加，吸附峰面积先增大后减小，整体呈“倒V”形。自由峰面积先减小后增大，整体呈“V”形。
