ACS Omega,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Feb. 21, 2025
The
structure
and
evolution
of
coal
are
intricately
linked
to
its
properties
at
both
nanometer
micrometer
scales.
refinement
pores
fractures
is
crucial
for
assessing
outburst
risks,
evaluating
coalbed
methane
(CBM)
reservoirs,
improving
the
CBM
recovery
efficiency.
This
study
involved
collecting
four
different
coal-body
samples
from
Zhaozhuang
colliery
in
southern
Qinshui
Basin.
We
conducted
laboratory
analyses
determine
physical
employed
X-ray
computed
tomography
(CT)
quantitatively
assess
pore
size
distribution
(PSD),
volume
contribution,
morphology,
connectivity
across
various
structures.
comparative
characteristics
these
structures
under
tectonic
stresses
discussed.
Results
reveal
that
hysteresis
loop
type
3#
anthracite
primarily
aligns
with
H3
as
per
IUPAC
classification,
featuring
predominantly
plate-like
wedge-shaped
scale.
A
shape
factor
was
introduced
categorize
types,
highlighting
sensitivity
structure.
Spherical
tubular
mainly
present
aperture
range
0-25
μm,
while
larger
apertures
appeared
prolate
spheroids
flat
fractures.
Primary
contains
more
spherical
or
pores,
whereas
shows
a
prevalence
slit
fractures,
suggesting
undergo
progressive
deformation,
either
breaking
elongating,
stress.
elastic
property
affected
by
multifactor
increased
changes
morphology.
Permeability
influenced
PSD
connectivity,
demonstrating
quadratic
positive
correlation
porosity,
aperture,
specific
surface
area.
Granular
exhibited
most
favorable
permeability
extraction.
trend
morphology
comprehensive
data
highlight
an
evolutionary
pattern
shaped
brittle
ductile
deformation
mechanisms.
Cataclastic
characterized
increase
new
granular
undergoes
rapid
fracture
formation
enhanced
strong
stress
conditions.
Mylonitic
develops
These
insights
into
can
significantly
enhance
our
understanding
efficiency
microscopic
mesoscopic
perspectives.
ACS Omega,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 7, 2025
The
distribution
of
mobile
water
during
slug
flows
in
coalbed
methane
(CBM)
wells
directly
affects
the
pressure
propagation
path.
In
this
article,
characteristics
gas
and
fractures
flow
are
characterized
by
gas–liquid
microscopic
experiments.
Fluid–structure
interaction
was
adopted
to
analyze
fracture
morphology
after
deformation
under
stress.
A
mathematical
model
critical
size
for
migration
established
through
nuclear
magnetic
resonance
tests,
contact-angle
theory
gas–water
equilibrium.
results
show
that
rate
liquid
length
period
plug
slug.
gas–liquid–solid
three-phase
properties
affect
shape
boundary.
When
is
transformed
into
bound
water,
deformed
an
hourglass
shape.
negatively
correlated
with
reservoir
contact
angle
a
power
exponent
while
linearly
positively
surface
tension.
Using
fracturing
fluids
low
tension
high
liquid–solid
angles
can
promote
expulsion
liquids
from
fractures,
thereby
achieving
higher
resource
productivity.
Mathematical
statistical
methods
have
been
employed
establish
rapid
calculation
movable
transport
size.
summary,
research
provides
effective
accurate
quantitative
method
evaluation
water.
Physics of Fluids,
Journal Year:
2025,
Volume and Issue:
37(4)
Published: April 1, 2025
The
carbon
dioxide-enhanced
coalbed
methane
process
enables
CO2
sequestration
and
enhances
(CBM)
extraction
efficiency,
offering
broad
application
potential
in
deep
CBM
development.
coal
fracture
surface
is
a
significant
medium
for
fluid
transport,
its
mechanical
properties
are
factors
affecting
the
migration
embedment
of
proppants.
results
show
that
as
gradually
transforms
into
supercritical
state,
indentation
depth,
creep
distance,
residual
depth
increase
gradually.
Young's
modulus,
hardness,
toughness
decrease
by
39.45%,
36%,
31.5%,
respectively,
controlled
depth.
irreversible
work
ratio
effectively
reflects
weakening
indirectly
confirms
plastic
deformation
an
change.
macromolecular
structure,
free
energy,
pore
fractures
important
contributing
to
properties,
mainly
manifested
destruction
reduction
expansion
fractures.
In
addition,
Burgers
model
better
validates
surfaces
during
stage.
This
greatly
reduces
resistance
crack
propagation
coal,
thus
decreasing
coal.
These
findings
provide
insights
behavior
context
geological
related
applications.
Abstract
Coal
pore
system
controls
physical
properties
of
coals
and
influences
CO
2
geological
sequestration
greatly.
By
using
cumulative
amplitude
ratio
method
nuclear
magnetic
resonance
(NMR)
measurements,
this
paper
classifies
coal
ten
samples
analyzes
the
function
each
on
property.
Following
cognitions
are
achieved.
Ten
can
be
divided
into
four
types,
they
all
developed
type,
diffusion
dominated
cleat
permeation
type.
Both
maximum
vitrinite
reflectance
apparent
density
have
slight
positive
relationships
versus
volumetric
percentage
pore,
while
negative
with
cleat.
Porosity
has
a
correlation
relationship
pore.
Irreducible
water
saturation
linear
added
by
40%
Permeability
an
exponential
50%
It
indicates
that
acts
as
combination
movable
irreducible
water,
both
them
occupy
nearly
half
volume
entire
However,
for
its
to
influence
permeability
is
more
emphatic
than
saturation.
great
significance
deeply
investigate
gas
migration
useful
guide
engineering
processes
during
coalbed
methane
drainage
sequestration.
