【作者】 许亚坤；

【导师】 陈江峰；

【作者基本信息】 河南理工大学 ， 地质资源与地质工程， 2010， 硕士

【摘要】 本文在采集了大量构造煤和原生结构煤样的基础上,通过扫描电子显微镜(SEM)、X射线衍射(XRD)和电子顺磁共振(EPR)等方法,分析了不同应力作用和变形环境条件下,构造煤微观结构之间的差异,以及构造煤的大分子结构随煤级和构造应力的变化规律,并探讨了引起构造煤结构变化的化学机理和控制因素。通过对构造煤的扫描电镜观察,根据所受构造应力的性质、大小、主次和作用条件的不同,构造煤的结构在微观尺寸上可以分为脆性变形系列和韧性变形系列两大类,前者包括脆性裂纹和显微角砾结构,后者包括透镜状结构、鳞片状结构和摩擦镜面。构造煤的X射线衍射分析反映了构造煤的晶体结构参数随构造应力增减的变化规律,并指出构造应力对煤的化学结构影响范围有限,一般在距应力集中区2m的范围之内;构造应力对芳香核的增高有很强的促进作用,而对芳香核的扩大作用则相对微弱。运用电子顺磁共振分析,发现在烟煤阶段构造煤自由基浓度随煤级升高而增大,而到无烟煤阶段又有减小的趋势,构造应力促进了芳构化作用和环缩合作用;烟煤阶段,在距构造部位1m的范围内,随着构造应力的减小,自由基浓度N_g迅速减小,超过这一范围N_g则渐趋平稳;区域变质作用的各种化学机制是引起构造煤的自由基浓度N_g变化的主要控制因素,构造作用引起的动力变质作用是引起构造煤的自由基浓度N_g变化的相对次要的控制因素。更多还原

【Abstract】 A large number of tectonic and primary structure coal samples collected from major coalfield of China have been studied by means of scanning electron microscope(SEM), x-ray diffraction(XRD) and electron paramagnetic resonance(EPR), The difference of the microstructure of tectonic coals formed under different tectonic stress and deformation environment conditions and the evolution law of macromolecular structure of tectonic coals with the variation of coal rank or the tectonic stress are analyzed, and The chemical mechanism and controlling factors which result in changing the structure of tectonic coals are discussed in this thesis.Through the observation of scanning electron microscope for tectonic coals, on the basis of the difference of the property, magnitude, primary-secondary and condition of the tectonic stresses, the structure of the tectonic coal at the micro size is subdivided into brittle-deformed series and ductile-deformed series. The former includes brittle crack and micro-breccia structure; the latter includes lentoid, squamose structure and mirror-like friction plane. The analysis of X-ray diffraction for tectonic coals indicates that the crystal structure of the tectonic coal is alternated along with the decrease of the tectonic stress, and the influence range of tectonic stress on the chemical structure of coal is limited, usually within 2m away from the stress concentration zone. It is expounded that the tectonic stress has a strong role in promoting the accumulation height of aromatic nucleus, and has a relatively weak effect on the expansion of aromatic nucleus. The result of electron paramagnetic resonance analysis shows that the free radical concentration of tectonic coals is elevated with the increase of coal rank in the bituminous coal stage, and has reduced tendency when the coal rank reach into the anthracite stage. The tectonic stress promotes the aromatizating process of the aromatic ring polymerization. In the bituminous coal stage,with the decrease of tectonic stress, the free radical concentration reduces rapidly within 1m away from the tectonic position,and is almost no changed in the farther position. Various chemical mechanisms causing regional metamorphism are the main controlling factors that result in the variety of the free radical concentration of tectonic coals, and the dynamic metamorphism caused by the tectonic stress is relatively minor controlling factors.更多还原