Absolute Gas Permeability Coefficient of Samples with Embedded Glass Capillaries: Comparison of Measurement Results and Theoretical Calculations

This article explores the possibility of using samples with embedded glass capillaries of various diameters as rock-mimicking samples with a-priori known values of the absolute gas permeability coefficients. The measured values of the absolute gas permeability coefficient were compared with those obtained by theoretical calculation. The results of measuring the absolute gas permeability coefficient were obtained using the State primary standard of units of specific gas adsorption, specific surface area, specific pore volume, pore size, open porosity, and gas permeability coefficient of solid substances and materials (GET 210-2019). The theoretical values of the permeability coefficient were obtained by measuring the diameters of the capillaries using an optical microscope. Based on the values of these diameters, the permeability coefficients of the samples with capillaries were calculated according to the combined Poiseuille and Darcy equation. It was proved that the measurement results obtained with the use of GET 210-2019 are consistent with the theoretically calculated values of the permeability coefficient within the uncertainty limits. In accordance with the obtained data, the possibility of utilizing cylindrical samples with embedded glass capillaries for measuring gas permeability coefficients of solid substances and materials has been confirmed. The results of this research will be useful for oil and gas professionals, for example, when performing petrophysical studies and geological exploration.