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Copyright of Chemical Engineering of Oil & Gas / Shi You Yu Tian Ran Qi Hua Gong is the property of PetroChina Southwest Oil & Gas Field Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A series of gas flow tests using He and CO2 are conducted on shale samples in triaxial flow equipment for rock to investigate the influencing mechanisms of pore pressure and temperature on permeability. The experimental results show that non-sorbing He permeability increases with pore pressure. However, the permeability evolution of sorbing CO2 first decreases and then recovers as pore pressure increases. Then, a theoretical model is proposed to predict the permeability change induced by effective stress, matrix swelling and gas slippage. Furthermore, the validation of the proposed model is conducted by fitting the experimental results from this paper. The flow tests under variable temperatures demonstrate that the shale permeability declines first at low temperature, and then increases at high temperature. It is observed that temperature has a stronger impact on permeability under lower confining pressure. With the increase of temperature, the slippage effects on the permeability become stronger. The effect of temperature on gas permeability is altered as a combined action of the thermal expansion of grains, gas slippage, the thermal motion of gas molecular and the matrix swelling induced by adsorption. At last a theoretical model is built with the consideration of temperature effects, and is validated by comparing the experimental results and analytic results, which gives satisfactory agreements between each other. [ABSTRACT FROM AUTHOR]