Geofluids,
Journal Year:
2023,
Volume and Issue:
2023, P. 1 - 12
Published: April 24, 2023
It
is
not
clear
how
the
distribution
of
retained
fracturing
fluids
and
its
effect
on
permeability
wettability
in
tight
oil
reservoirs
interact.
Especially,
there
are
more
qualitative
studies
less
quantitative
this
issue.
Under
laboratory
experimental
conditions,
paper
clarifies
core
reveals
influence
rule
reservoir
wettability.
found
that
main
retention
space
a
microporous
interval,
residual
after
displacement
by
mainly
exists
form
dots
or
porphyries.
The
smaller
porosity
will
lead
to
fluids.
different
cores
fluid
has
decreased
varying
degrees
compared
with
before
retention.
slices
was
tested,
significant.
This
study
important
significance
for
improving
recovery
enhancing
understanding
postfracturing
Journal of Rock Mechanics and Geotechnical Engineering,
Journal Year:
2024,
Volume and Issue:
unknown
Published: July 1, 2024
Forced
imbibition,
the
invasion
of
a
wetting
fluid
into
porous
rocks,
plays
an
important
role
in
effective
exploitation
hydrocarbon
resources
and
geological
sequestration
carbon
dioxide.
However,
interface
dynamics
influenced
by
complex
topology
commonly
leads
to
non-wetting
trapping.
Particularly,
underlying
mechanisms
under
viscously
unfavorable
conditions
remain
unclear.
This
study
employs
direct
numerical
simulation
method
simulate
forced
imbibition
through
reconstructed
digital
rocks
sandstone.
The
fluid–fluid
interactions
are
investigated
transient
simulations,
while
pore
metrics
introduced
analyze
impact
on
steady-state
residual
distribution
obtained
pseudo-transient
scheme.
results
show
that
cooperative
pore-filling
process
promoted
corner
flow
is
dominant
at
low
capillary
numbers.
unstable
inlet
pressure,
mass
flow,
curvature,
which
correspond
complicated
higher
saturation.
During
curvature
gradually
increases,
with
involving
cooperation
main
terminal
meniscus
movement
arc
menisci
filling.
Complex
small
diameter
pores
may
result
destabilization
curvature.
saturation
negatively
correlated
porosity
throat
size,
positively
tortuosity
aspect
ratio.
A
large
mean
coordination
number
characterizing
global
connectivity
promotes
imbibition.
high
characterized
standardized
Euler
corresponding
associated
probability
Natural Gas Industry B,
Journal Year:
2023,
Volume and Issue:
10(4), P. 323 - 332
Published: Aug. 1, 2023
A
large
amount
of
fracturing
fluid
in
hydraulic
is
imbibed
into
the
shale
fracture/matrix,
which
leads
to
significant
uncertainty
gas
recovery
evaluation.
The
mechanism
imbibition
impact
on
gas–water
flow
not
well
understood.
In
this
study,
systematic
comparative
experiments
are
carried
out
simulate
fractured
samples
obtained
from
Wufeng-Longmaxi
reservoirs
China,
and
effect
fracture–matrix
system
qualitatively
quantitatively
investigated.
Nine
cores
collected
measure
their
porosity
permeability
using
a
helium
porosimeter
nitrogen
pulse–decay
tests.
Gas/liquid
single-phase
then
methane
KCl
solution,
respectively.
Subsequently,
dynamic
three
visual
cell.
interfacial
tension,
water
amount,
displacement
velocity
recorded.
gas/liquid
test
shows
high
linear
correlation
between
pressure
gradient
as
fracture
main
channel,
dominantly
determining
behavior.
Moreover,
capillary
force
was
introduced
cross-flow
term
triple-medium
model
characterize
effect,
two-phase
simulation
considering
retention
developed,
behavior
by
reservoir
analyzed.
Valuable
experiment
data
work
provided,
can
be
used
validate
analytical
equations
for
gas/water
system.
Polymers,
Journal Year:
2023,
Volume and Issue:
15(6), P. 1560 - 1560
Published: March 21, 2023
Fracturing
fluids
are
widely
applied
in
the
hydraulic
fracturing
of
shale
gas
reservoirs,
but
fluid
flowback
efficiency
is
typically
less
than
50%,
severely
limiting
recovery.
Additionally,
mechanism
and
main
influencing
factors
unclear.
In
this
study,
microscopic
experiments
conducted
to
simulate
progress
reservoirs.
The
affecting
flowback/retention
fracture
zone
were
analyzed
clarified.
Results
show
that
ultimate
positively
correlated
with
concentration
driving
pressure
difference.
There
four
kinds
mechanisms
responsible
for
retention
pore
network:
viscous
resistance,
Jamin
effect,
blockage
effect
dead
end
pore.
increases
linearly
increasing
capillary
number.
These
insights
will
advance
fundamental
understanding
reservoirs
provide
useful
guidance
development.
Petroleum Science and Technology,
Journal Year:
2024,
Volume and Issue:
unknown, P. 1 - 19
Published: Dec. 5, 2024
The
CO2-assisted
fracturing
fluid
displacement
technology
is
of
great
significance
for
enhancing
oil
recovery
(EOR)
tight
reservoirs,
while
the
characteristics
and
mechanism
microscopic
production
are
still
unclear.
In
this
study,
experiments
were
launched
with
two
various
methods,
nuclear
magnetic
resonance
(NMR)
high-temperature
-pressure
visualization
system
respectively.
experimental
results
show
that
crude
in
mesopores
macropores
mainly
displaced
by
fluids,
residual
retained
micropores
small
pores.
improved
more
recovered
from
pores,
macropores,
less
content
form
flake
droplet.
This
study
provides
a
prospective
EOR
efficient
development
reservoirs.
Physics of Fluids,
Journal Year:
2024,
Volume and Issue:
36(12)
Published: Dec. 1, 2024
Slickwater
fracturing
can
significantly
enhance
shale
gas
production.
However,
following
operations,
a
portion
of
the
slickwater
will
inevitably
remain
in
reservoir,
thereby
altering
pore
structure
reservoir
and
impacting
output.
By
slickwater,
we
mean
fluid
mixture
composed
water,
friction
reducers,
various
additives,
typically
used
hydraulic
to
facilitate
creation
fractures
reservoir.
This
study
focuses
on
investigating
influence
multi-scale
reservoirs
through
experimental
techniques,
including
high-pressure
mercury
intrusion,
low-temperature
nitrogen
adsorption,
carbon
dioxide
adsorption
experiments.
The
findings
reveal
that
under
pressure,
infiltrates
pores,
with
higher
concentrations
accumulating
macropores
mesopores.
Additionally,
increased
pressure
or
concentration
exacerbates
damage
structure.
Fractal
analysis
further
demonstrates
obstructs
diminishes
complexity
network,
while
adhering
rough
surfaces
reduce
surface
roughness.
Consequently,
trapped
diffusion
thus
reduces
Journal of Energy Resources Technology,
Journal Year:
2024,
Volume and Issue:
146(10)
Published: June 4, 2024
Abstract
Shut-in
and
flowback
are
critical
stages
following
hydraulic
fracturing
in
shale
oil
wells.
Researching
the
distribution
of
reservoir
pressure
fluid
flow
mechanism
during
shut-in
is
important
for
optimizing
these
procedures,
thereby
enhancing
well
productivity.
Therefore,
based
on
oil,
this
article
establishes
a
equation
considering
imbibition
seepage,
using
linear
source
superposition
equivalent
to
generated
by
as
initial
condition.
The
PEBI
(Perpendicular
BIsection)
grid
used
divide
multistage
fractured
horizontal
simulation
results
reveal
that
large-volume
leads
formation
high-pressure
zone
around
wellbore,
significantly
surpassing
original
pressure,
termed
high-energy
band.
This
band
demarcated
from
boundary
line
(PBL).
During
production,
double-pressure
funnel
(DPF)
manifests
within
reservoir,
generating
region
with
utmost
at
specific
position
band,
known
peak
line.
Oil
located
beyond
unable
toward
wellbore.
According
DPF
theory
technology
should
be
adopted
form
long
straight
fractures
far
possible
whenever
feasible
cross
optimal
duration
contingent
upon
movement
rate
curve.
Energy & Fuels,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 2, 2024
Supercritical
CO2
(ScCO2)
soaking
significantly
impacts
pore
structure
evolution
and
oil
composition
in
tight
shale
reservoirs.
This
study
conducted
static
experiments
under
actual
reservoir
temperature
pressure,
the
brine
deionized
water
were
used
as
control
fluids.
The
variations
structures
properties
are
characterized
using
scanning
electron
microscopy
(SEM),
X-ray
diffraction,
low-field
nuclear
magnetic
resonance
core
analysis
system,
low-temperature
nitrogen
adsorption,
gas
chromatography
samples
before
after
ScCO2
soaking.
Results
show
enhances
connectivity,
particularly
microscale
mesoscale
pores,
by
dissolving
carbonates
feldspar,
increasing
volume
(+30%),
surface
area
(+4.9%),
average
diameter
(+9%).
SEM
images
reveal
fracture
expansion
new
formation
due
to
mineral
dissolution
precipitation
during
Wettability
shows
a
shift
from
water-wet
CO2-wet
conditions,
with
increased
contact
angles
for
(+18.8%)
(+40.5%)
15
days.
An
trend
hydrophobicity
of
matrix
can
be
observed.
Gas
indicates
rise
C15–C30
fractions
heavy
hydrocarbons,
oil's
molecular
weight
298.36
g/mol.
These
findings
provide
insights
into
feasibility
enhance
recovery
sequestration
Enhancing
connectivity
altering
wettability
potentially
improve
development.
Geofluids,
Journal Year:
2023,
Volume and Issue:
2023, P. 1 - 12
Published: April 24, 2023
It
is
not
clear
how
the
distribution
of
retained
fracturing
fluids
and
its
effect
on
permeability
wettability
in
tight
oil
reservoirs
interact.
Especially,
there
are
more
qualitative
studies
less
quantitative
this
issue.
Under
laboratory
experimental
conditions,
paper
clarifies
core
reveals
influence
rule
reservoir
wettability.
found
that
main
retention
space
a
microporous
interval,
residual
after
displacement
by
mainly
exists
form
dots
or
porphyries.
The
smaller
porosity
will
lead
to
fluids.
different
cores
fluid
has
decreased
varying
degrees
compared
with
before
retention.
slices
was
tested,
significant.
This
study
important
significance
for
improving
recovery
enhancing
understanding
postfracturing
