Influence of Extreme Temperature on the Pore and Fracture Development of High-Rank Coal
Influence of Extreme Temperature on the Pore and Fracture Development of High-Rank Coal
复制标题
极端温度对高阶煤孔隙和裂隙发育的影响
DOI：
10.1155/2018/4529751
复制
发表时间：
2018
影响因子：
1.8
通讯作者：
Bi Jingcang
中科院分区：
文献类型：
--
作者：
Yang Ming;Bi Jingcang
煤中孔隙裂隙结构及其分布特征对煤层气的富集和渗透运移具有重要作用。煤储层中的孔隙和裂缝在超低温应力作用下的改造和修复，如煤储层的液氮冻裂和热破裂等，已引起广泛的研究关注。本研究使用Meso MR 23 - 060 H-I低场核磁共振成像仪对两种极端温度（100°C、−196°C）下煤样的孔隙和断裂特征进行了核磁共振（NMR）实验。探讨了超高温和超低温应力对高煤级煤孔隙和裂隙发育的影响规律。结果表明，温度可以影响高煤阶煤样的孔隙和裂隙发育。煤样的孔体积、孔隙率和渗透率在低温（−196°C）处理后增加。小孢子比例减少，小孔比例增加，中孔比例不变，大孢子比例有所增加。煤样经高温（100°C）处理后孔体积减小。孔隙度和渗透率降低。中孔比例下降，中孔比例基本不变，大孢子比例减少。
Pore and fracture structures in coals and their distribution features play an important role in the enrichment and osmosis migration of coalbed methane (CBM). The modification and antireflection of pore and fracture in coal reservoir through ultrahigh and ultralow temperature stress, such as liquid nitrogen frozen‐induced cracking and thermal antireflection of coal reservoir, have attracted wide research attention. This study conducted a nuclear magnetic resonance (NMR) experiment of pore and fracture features of coal samples under two extreme temperatures (100°C, −196°C) using the Meso MR23‐060H‐I low‐field NMR and imaging instrument. The influencing law of ultrahigh and ultralow temperature stress on pore and fracture development in high‐rank coal was discussed. Results demonstrated that temperature can influence pore and fracture development of high‐rank coal samples. The pore volume, porosity, and permeability of the coal sample increase after low‐temperature (−196°C) treatment. The proportion of microspores decreases, the proportion of small pores increases, the proportion of mesopores remains the same, and the proportion of macrospores increases to some extent. The pore volume of coal sample decreases after high‐temperature (100°C) treatment. Porosity and permeability decrease. The proportion of mesopores declines, the proportion of mesopores remains basically same, and the proportion of macrospores decreases.