Numerical Research On The Transport Of Particle In Micro Structure Of Digital Core With Micron X-ray CT

When traditional rock physics experiments are applied to unconventional reservoirs,it is difficult to study the influence of complex rock microstructures on the macroscopic physical properties of rocks.Digital core techniques can effectively solve these problems.At present,most of the digital cores at home and abroad have only simple pure rock skeletons and pores in the three-dimensional reconstruction.However,the complex skeleton mineral components of the rock also affect the macroscopic physical properties of the rock.In this paper,the multi-threshold segmentation method is used to segment the microscopic pore structure from the X-CT gray image of shale,and the digital core is constructed by using the three-dimensional reconstruction method.Based on this,the neutron transmission characteristics are simulated to study different pore fluids,The effects of mineral composition and kerogen in shale on neutron transmission.The simulation results show that the neutron transmission imaging can well identify the hydrogen-containing material in the digital core.Based on the research results,it is found that the shale has a strong heterogeneity;the macroscopic reaction cross section of the different mineral components of the rock skeleton to neutrons Different,it can be used to divide the digital core mineral composition;For the digital core of a single skeleton composition,when the pores are saturated with water,the neutron count difference has a strong positive correlation with the core porosity,when the pore fluid is CH₄,The sub-count difference will become negative,and the greater the porosity,the smaller the neutron count difference.When the pore-saturated fluid is C₂₂H₄₆,the difference in neutron count difference is not significantly different from that in pore-saturated water;kerogen pairing The sub-count difference has a great influence.When the rock skeleton contains a large amount of kerogen,the difference between the porosity and the neutron count is basically no longer relevant.