Gas flow patterns in rock samples

The article discusses permeability testing of rock samples (coal, sandstone, dolomite) using methane, nitrogen and helium. Gas was fed under pressure at one side of a sample, and the other side of the sample was closed for gas flow. Gas filled the sample with time, gas flow stopped, and equilibrium settled in the sample. Gases were fed at different inlet pressures, and the nonstationary time dependences of pressure were recorded at the sample inlet and outlet. As a rule, in the final equilibrium, pressure became constant at the inlet and outlet, and in the whole sample. However, in some cases of inlet pressure variations, the pressures at the sides of the sample after equilibration differed a few times. The found patterns of flow mass transfer are probably connected with gas adsorption in the samples. The tests can be a basis for a cardinally new approach to permeability determination in porous materials using the nonstationary flow laws. This is valid in full measure if non-adsorbable gases are used in the permeation tests.

Averin A. P., Belousov F. S., Pashichev B. N., Trofimov V. A. Gas flow patterns in rock samples. MIAB. Mining Inf. Anal. Bull. 2021;(10):100-111. [In Russ]. DOI: 10.25018/0236_1493_2021_10_0_100.

Исследование выполнено при поддержке Министерства науки и высшего образования Российской Федерации, Соглашение №075-15-2021-943 и European Commission Research Fund for Coal and Steel (RFCS) funded project "Advanced methane drainage strategy employing underground directional drilling technology for major risk prevention and greenhouse gases emission mitigation" GA: 847338 — DD-MET — RFCS-2018/RFCS-2018

A.P. Averin¹, Cand. Sci. (Eng.), Senior Researcher,
F.S. Belousov¹, Researcher,
B.N. Pashichev¹, Researcher,
V.A. Trofimov¹, Dr. Sci. (Eng.), Chief Researcher, e-mail: asas_2001@mail.ru,
¹ Institute of Problems of Comprehensive Exploitation of Mineral Resources of Russian Academy of Sciences, 111020, Moscow, Russia.

V.A. Trofimov, e-mail: asas_2001@mail.ru.

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