Research on the Influence of Gas on Coal Pores based on NMR Technology
Abstract
In order to study the change characteristics of the pore structure of coal under different CH4 pressure conditions, nuclear magnetic resonance (NMR) technology was used to test the degree of influence on porosity and pore size distribution of coal after the adsorption of CH4 under different pressures. The test results show that under the action of gas pressure, the NMR signal amplitude of the NMR T2 spectrum changes significantly. From the distribution area of the T2 spectrum of the coal sample, it can be known that the peak peak area of small holes>the peak peak area of medium and large holes>the peak peak area of cracks indicates that the coal sample The micropores in the coal body are the most developed, and the connectivity is not strong, and it is difficult to circulate; in the range of gas pressure P=0.5~2.0MPa, as the gas pressure increases, new pores will be generated in the coal body, and the micropores are interconnected to form micropores or medium Pores and mesopores are interconnected to form cracks, thereby increasing the porosity and permeability of the coal sample.References
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