摘要
There is a more consanguineous relation be-tween nano-scale deformation of coal structure and meta-morphic-deformed environment. In different metamor-phic-deformed environments, deformation in the coal struc-ture can occur not only at micro-scale, but also at nano-scale, and even leads to the change of molecular structure and nano-scale pore (<100 nm) structure. The latter is the main space absorbing coalbed methane. Through X-ray diffraction (XRD) and liquid–nitrogen absorption methods, the charac-teristics of macromolecular and nano-scale pore structures of coals in different metamorphic-deformed environments and deformational series of coals have been studied. By combin-ing with high-resolution transmission electron microcopy (HRTEM), the macromolecular and nano-scale pore struc-tures are also directly observed. These results demonstrate that the stacking Lc of the macromolecular BSU in tectonic coals increases quickly from the metamorphic-deformed environment of low rank coals to that of high rank coals. For different deformed tectonic coals, in the same metamor-phic-deformed environment, the difference of Lc is obvious. These changes reflect chiefly the difference of different tem-perature and stress effect of nano-scale deformation in tec-tonic coals. The factor of temperature plays a greater role in the increase of macromolecular structure parameters Lc, the influence of stress factor is also important. With the stress strengthening, Lc shows an increasing trend, and La /Lc shows a decreasing trend. Therefore, Lc and La /Lc can be used as the indicator of nano-scale deformation degree of tectonic coals. With increasing temperature and pressure, especially oriented stress, the orientation of molecular structure be-comes stronger, and ordering degree of C-nets and the ar-rangement of BSU are obviously enhanced. For the deforma-tion of nano-scale pore structure, in the same metamor-phic-deformed environment, along with the strengthening of stress, the ratio of mesopores to its total pores volume of tec-toni
There is a more consanguineous relation between nano-scale deformation of coal structure and metamorphic-deformed environment. In different metamorphic-deformed environments, deformation in the coal structure can occur not only at micro-scale, but also at nano-scale, and even leads to the change of molecular structure and nano-scale pore （〈100 nm） structure. The latter is the main space absorbing coalbed methane. Through X-ray diffraction （XRD） and liquid-nitrogen absorption methods, the characteristics of macromolecular and nano-scale pore structures of coals in different metamorphic-deformed environments and deformational series of coals have been studied. By combining with high-resolution transmission electron microcopy （HRTEM）, the macromolecular and nano-scale pore structures are also directly observed. These results demonstrate that the stacking Lc of the macromolecular BSU in tectonic coals increases quickly from the metamorphic-deformed environment of low rank coals to that of high rank coals. For different deformed tectonic coals, in the same metamorphic-deformed environment, the difference of Lc is obvious. These changes reflect chiefly the difference of different temperature and stress effect of nano-scale deformation in tectonic coals. The factor of temperature plays a greater role in the increase of macromolecular structure parameters Lc, the influence of stress factor is also important. With the stress strengthening, Lc shows an increasing trend, and La/Lc shows a decreasing trend. Therefore, Lc and La/Lc can be used as the indicator of nano-scale deformation degree of tectonic coals. With increasing temperature and pressure, especially oriented stress, the orientation of molecular structure becomes stronger, and ordering degree of C-nets and the arrangement of BSU are obviously enhanced. For the deformation of nano-scale pore structure, in the same metamorphic-deformed environment, along with the strengthening of stress, the ratio of mesopores to its total pores volume of tectonic coa
基金
This work was supported by the National Key Development Plan Project of Basic Research(973 Plan)(Grant No.2002CB211704)
the National N atural Science Foundation of China(Grant No.40172058)
China Postdoctoral Science Foundation(Grant No.200403508)
Kuancheng Wang Post-doctoral Research Award Fund of Chinese Academy of Sciences.
关键词
煤结构
纳米变形
大分子结构
地质环境
coal structure, nano-scale deformation, macromolecular structure, pore structure, metamorphic-deformed environment.
