XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 3561
construction of the pore network model is based on the
principle of the maximal sphere algorithm, which selects a
point among the pore pixels in a 3D digital core. It uses it
as the center of the sphere to continually increase its radius
and extend it in all directions until its surface touches the
nearest rock skeleton. The collection of all pixels in the
formed area is called the maximal sphere. A large sphere
can overlap with an adjacent maximal sphere of a radius
smaller than its own, which results in the formation of a
maximal sphere cluster, and all the pores in the digital core
are filled by maximal sphere clusters. Maximal ball clusters
fill all pores in the digital rock core. The sphere with the
largest radius in the maximal ball multicluster is defined as
the ancestor of the cluster. If a particular ball in a maximal
ball multicluster possesses two ancestors, this joint maximal
ball is defined as a throat. Then, the throat length is defined
as lt, shown in Figure 11, using the corresponding correc-
tion method. Using the principle of the maximal sphere
model and maximal sphere algorithm, we can effectively
overcome the drawbacks of the equivalent sphere diameter
method that cannot analyze the pore throat parameters in
the connected pore cluster and construct the correspond-
ing network model of pore and throat structure, and at the
same time, the use of mathematical and statistical methods
can also realize the quantitative analysis of the pore struc-
ture such as the pore radius, throat ratio, and so on, to get
the characterization parameter of the pore structure of the
permeable bricks[El-Khatib N, 1995].
The maximum ball algorithm was used to construct
the pore-throat network ball-and-stick model. The ball-
and-stick model is shown in Figure 12, in which the ball-
and-stick represents connected pores and the separate ball
model represents unconnected pores, and the characteriza-
tion parameters, such as pore radius and throat radius, were
quantified respectively. The results of the quantitative anal-
ysis of pore structural parameters, such as the pore radius
and throat radius, are shown in Figure 13. The results of the
quantitative evaluation of the structural parameters of the
pores and the throats were also carried out and the results
are shown in Table 3 [Wang et al., 2013].
As can be seen from Figure 13 and Table 3, the pore
radius of permeable bricks shown in Figure 13a has a
skewed distribution, which is mainly concentrated within
1200 μm, with the highest distribution probability near
the pore radius of 300 μm, with an average pore radius of
273.47 um, and the maximum pore radius reaching 856.89
um. Figure 13b shows the distribution of the throat radius
of permeable bricks, the throat radius is skewed distribu-
tion, the throat radius is mainly distributed in 20–300 μm,
and the average throat radius is 83.39 um, but there are
some throat radius more than 400 μm, and the maximum
throat radius reaches 438.98 um. Overall, the results of
pore radius, throat radius, analyses of the permeable bricks
Figure 11. Schematic diagram of the maximal ball algorithm
Figure 12. Ball-and-stick model of permeable brick pore and
throat network
construction of the pore network model is based on the
principle of the maximal sphere algorithm, which selects a
point among the pore pixels in a 3D digital core. It uses it
as the center of the sphere to continually increase its radius
and extend it in all directions until its surface touches the
nearest rock skeleton. The collection of all pixels in the
formed area is called the maximal sphere. A large sphere
can overlap with an adjacent maximal sphere of a radius
smaller than its own, which results in the formation of a
maximal sphere cluster, and all the pores in the digital core
are filled by maximal sphere clusters. Maximal ball clusters
fill all pores in the digital rock core. The sphere with the
largest radius in the maximal ball multicluster is defined as
the ancestor of the cluster. If a particular ball in a maximal
ball multicluster possesses two ancestors, this joint maximal
ball is defined as a throat. Then, the throat length is defined
as lt, shown in Figure 11, using the corresponding correc-
tion method. Using the principle of the maximal sphere
model and maximal sphere algorithm, we can effectively
overcome the drawbacks of the equivalent sphere diameter
method that cannot analyze the pore throat parameters in
the connected pore cluster and construct the correspond-
ing network model of pore and throat structure, and at the
same time, the use of mathematical and statistical methods
can also realize the quantitative analysis of the pore struc-
ture such as the pore radius, throat ratio, and so on, to get
the characterization parameter of the pore structure of the
permeable bricks[El-Khatib N, 1995].
The maximum ball algorithm was used to construct
the pore-throat network ball-and-stick model. The ball-
and-stick model is shown in Figure 12, in which the ball-
and-stick represents connected pores and the separate ball
model represents unconnected pores, and the characteriza-
tion parameters, such as pore radius and throat radius, were
quantified respectively. The results of the quantitative anal-
ysis of pore structural parameters, such as the pore radius
and throat radius, are shown in Figure 13. The results of the
quantitative evaluation of the structural parameters of the
pores and the throats were also carried out and the results
are shown in Table 3 [Wang et al., 2013].
As can be seen from Figure 13 and Table 3, the pore
radius of permeable bricks shown in Figure 13a has a
skewed distribution, which is mainly concentrated within
1200 μm, with the highest distribution probability near
the pore radius of 300 μm, with an average pore radius of
273.47 um, and the maximum pore radius reaching 856.89
um. Figure 13b shows the distribution of the throat radius
of permeable bricks, the throat radius is skewed distribu-
tion, the throat radius is mainly distributed in 20–300 μm,
and the average throat radius is 83.39 um, but there are
some throat radius more than 400 μm, and the maximum
throat radius reaches 438.98 um. Overall, the results of
pore radius, throat radius, analyses of the permeable bricks
Figure 11. Schematic diagram of the maximal ball algorithm
Figure 12. Ball-and-stick model of permeable brick pore and
throat network