Morphological determination of pore connectivity as a function of pore size using serial sections

Abstract

The geometry of pore space in soil is considered to be the key in understanding transport of water, gas and solute. However, a quantitative and explicit characterization, by means of a physical interpretation, is difficult because of the geometric complexity of soil structure.Pores larger than 40 pm within two soil horizons have been analysed morphologically on 3-dimensional digital representations of the pore space obtained by serial sections through impregnated specimens. The Euler-Poincark characteristic has been determined as an index of connectivity in three dimensions. The pore connectivity is quantified as a function of the minimum pore diameter considered leading to a connectivity function of the pore space. Different pore size classes were distinguished using 3dimensional erosion and dilation. The connectivity function turned out to differentiate between two soil materials. The pore space in an upper Ah horizon is intensely connected through pores between 40 and 100 pm, in contrast to the pore space in the AhBv beneath it. The morphological pore-size distributions were compared to the pore-size distribution obtained by water retention measurements. The discrepancy between these different methods corresponds to the expectation due to pore connectivity.

Influence of pore size and geometry on peat unsaturated hydraulic conductivity computed from 3D computed tomography image analysis

“…Tortuosity can easily be related to the hydraulic conductivity of a porous medium because it provides an indication of increased resistance to flow due to the greater path length of the pore system; i.e. an increased path length results less connection or reducing the hydraulic conductivity (Dullien, 1979; Vogel, 1997). The connectivity of the pore space plays an important role in soil hydraulic properties and in its hysteretic behaviour; however, a quantitative morphological description of the connectivity of the complex porous structure in peat soil is difficult.…”

Narrowing the Loop for Microporosity Quantification in Carbonate Reservoirs Using Digital Rock Physics and Other Conventional Techniques

“…Matched coordination number distribution (large pores tend to have a higher coordination number); Appropriate correlations between pores and throats (aspect ratio); Connection probability: the smaller the distance between two pores, the larger is the probability of being connected, but under the control of a pore distance distribution with a restriction on the maximal distance (Vogel, 2008), (Vogel and Roth, 2001). Comparing the radius distribution of the generated original fine nano-CT (microporosity) and MCT (macroporosity) derived pore network, we can observe that the pore sizes of the microporous phase hardly exceed 1.5 micro-meter radius, those of the MCT (macroporosity) start at around 1 micro-meters radius (due to the voxel size of 2.6 microns).…”

Synthesis of Fe3O4@poly(methylmethacrylate-co-divinylbenzene) magnetic porous microspheres and their application in the separation of phenol from aqueous solutions

“…Particularly, the pore connectivity is an important parameter for some applications of the magnetic porous microspheres, because the efficiency of the adsorption of porous microspheres is affected by the pore connectivity. The pore size distribution curves can be used to indicate the pore connectivity [52]. The N 2 sorption derived data show a large population of pores in the mesopore region extending to the lower part of macropore region (MPMS1-9).…”