The Influence of Electrical Pulses on the Evolution Characteristics of Coal Pore Structur

Lu Chang; Juan Huang; Haofei Zheng

doi:10.62051/ijnres.v5n3.16

Authors

Lu Chang
Juan Huang
Haofei Zheng

DOI:

https://doi.org/10.62051/ijnres.v5n3.16

Keywords:

Coalbed methane; High voltage electric pulse; Pore structure characteristics.

Abstract

China is rich in coalbed methane resources, comparable to conventional natural gas, with enormous development potential. However, low-permeability and low-pressure coal reservoirs are widespread, leading to generally low single-well production. This paper focuses on the coal samples from Zhangcun, Lu'an, and uses an independently developed high-voltage electric pulse fracturing platform to conduct high-voltage electric pulse fracturing experiments on coal bodies. Mercury pressure and liquid nitrogen adsorption techniques were employed to analyze changes in pore structure before and after fracturing. The conclusions are as follows: High-pressure mercury pressure test data show that after high-voltage electric pulse fracturing, the macroporosity and mesoporosity of the Zhangcun coal sample increase, along with their proportion of total pore volume, indicating that the electric pulse shock wave primarily affects the meso-and macroporosity of the coal body. Low-temperature liquid nitrogen adsorption data indicate that high-voltage electric pulse fracturing reduces the liquid nitrogen adsorption capacity of the Zhangcun coal sample, altering the internal pore morphology. The ink bottle pores in the Zhangcun coal sample are effectively modified after fracturing. Analysis of liquid nitrogen adsorption data shows that after high-voltage electric pulse fracturing, the average pore size of the mesopores in the Zhangcun coal sample increases, while the pore volume and specific surface area decrease, indicating that the modified coal sample exhibits pore transformation.

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