Study on Degradation Mechanism of Stress in Generation Process of Coal-Bed Methane

Abstract:

In order to discuss the effect of tectonic stress on the structural evolution of coal, given the importance attached to High-resolution Transmission Electron Microscopy and micro-FTIR analysis, we investigated several aspects of material structures of high-rank Carboniferous period coal, located in the northern foreland basin of the Dabie orogenic belt in eastern China. High powered crystal lattice images of Bright Fields (BF) and Selected Area Diffraction patterns (SAD) of different types of metamorphism in coal were obtained. The organic molecular characters of different metamorphism types coal and the effecting factors are studied. The results show that:(1) the Basic Structural Units (BSU) become increasingly more compact as a function of rising temperature and pressure. Under pressure, the local orientation of molecules is strengthened, the arrangement of BSU speeds up and the degree of order is clearly enhanced; (2) tectonic stress is in favor of the chemistry environment transfer of hydrogen in coal, resulting in the decrease of aliphatic hydrocarbon and the increase of aromatic hydrocarbon in content, and accelerating the polycondensation and ordering of large molecules texture of coal.

• Periodical: Advanced Materials Research (Volumes 1073-1076)
• Pages: 1995-2000
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1073-1076.1995
• Online since: December 2014
• Authors: Xiao Ming Li*
• Keywords: Dabie Orogenic Belt, High-Rank Coal, High-Resolution Transmission Electron Microscopy, Micro-FTIR Analysis, Tectonic Stress

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