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Fig. 1. WYF-I high-temperature and high-pressure pyrolysis reaction device
2. Permeability test device
Smart perm III gas permeability measurement was adopted to conduct the permeability test, and the device utilizes the core pulse pressure attenuation test method proposed
by BRACE in 1968[16], which can measure the permeability from 9.87 × 10 −8 to 9.87 ×
10 −3 µm 2 .
Figure 2 showed a schematic diagram of the structure of a gas permeability measuring
instrument. The main features of the device are that it has upstream and downstream
gas chambers and can maintain constant pressure so that the entire rock specimen is
in a relatively stable stress state. In the process of permeability measurement, open the
micro-osmosis valve of the test piece, so that the upstream and downstream gas chambers
produce a gas pressure difference of up to 0.25 MPa; set a reasonable collection pressure
difference interval, and calculate by monitoring the relationship between the gas pressure
difference and time rock mass [17].
Fig. 2. Smart III gas permeability measurement instrument