ACS Omega,
Journal Year:
2024,
Volume and Issue:
9(13), P. 15259 - 15270
Published: March 25, 2024
Injection
of
carbon
dioxide
offers
substantial
social
and
economic
advantages
for
reduction
emission
reduction.
Utilizing
CO2
in
shale
formations
can
significantly
enhance
the
extraction
oil
or
gas.
Conducting
fundamental
research
on
how
affects
rock's
physical
properties
is
crucial
enhancing
its
porosity
permeability.
Particularly
deep
layers,
effects
supercritical
should
be
investigated
at
a
high
temperature
pressure,
differing
from
standard
conditions
applied
shallower
layers.
A
study
examined
impact
under
such
pore-throat
structure
mineral
composition
shale.
The
experimental
parameters
included
immersing
rock
pressures
ranging
10
to
70
MPa
temperatures
between
55
95
°C.
This
evaluated
changes
composition,
(using
scanning
electron
microscopy
nitrogen
adsorption
tests),
permeability
rocks.
Findings
indicated
that
dissolution
altered
relative
content
certain
minerals.
average
quartz
rose
and,
potassium
feldspar
contents
plagioclase
declined
conversely.
When
increasing
an
increase
I/S
mixed
layer
decrease
illite
were
observed
kaolinite
experienced
minor
changes.
temperature,
kaolinite,
layer,
chlorite
all
exhibited
decreasing
trend
with
while
increased.
Some
pores
become
rounded
high-magnification
view
dissolution.
Additionally,
Brunauer–Emmett–Teller
specific
surface
area,
pore
volume,
porosity,
generally
improved
pressure
temperature.
With
increased,
curves
absorption
had
moved
first
upward
then
downward.
However,
conditions,
enhancement
effect
could
diminish
even
negatively
shale's
These
findings
underscore
need
optimize
injection
high-temperature
high-pressure
conditions.
aims
provide
theoretical
guidance
efficient
use
applications
gas
output.
Energy & Fuels,
Journal Year:
2022,
Volume and Issue:
36(17), P. 9882 - 9903
Published: Aug. 23, 2022
Hydraulic
fracturing
has
transformed
the
international
energy
landscape
by
becoming
go-to
method
for
exploitation
of
natural
gas
from
unconventional
shale
reservoirs.
However,
in
recent
years,
search
an
alternative
shale-gas
exploration
intensified,
because
various
problems
(e.g.,
contamination
ground
and
surface
water,
overexploitation
precious
water
resources,
air
pollution,
etc.)
associated
with
usage
water-based
techniques.
The
use
CO2
emerged
as
a
better
to
aqueous-based
when
injected
into
deep
reservoirs,
transitions
supercritical
(SC-CO2)
temperature
pressure
condition
exceeds
critical
point,
i.e.,
31.1
°C
7.38
MPa.
In
this
paper,
we
comprehensively
review
impact
SC-CO2
on
reservoirs
during
different
stages
exploration,
(i)
drilling,
which
involves
superiority
over
drilling
fluids,
terms
achieving
under-balanced
well
condition,
higher
rates
penetration,
resistance
formation
damage;
(ii)
fracturing,
factors
affecting
tortuosity
fractures
created
breakdown
pressure,
proppant-carrying
capacity;
(iii)
injection,
twin-headed
benefit
enhanced
recovery
due
CO2/CH4
competitive
adsorption
geological
sequestration,
vs
CH4
excess
sorption
function
etc.
Several
research
works
have
indicated
discrepancies
how
impacts
properties.
Some
studies
show
low-pressure
N2-gas-adsorption-derived
area
total
pore
volume
be
increasing
imbibition,
while
others
decreasing
trend
same.
Similarly,
some
shales,
quartz
content,
along
clay
mineral
contents,
decreased
exposure
increased,
other
studies,
similar
long-term
SC-CO2,
content
was
observed
increase
decrease
vice
versa.
Essentially,
increased
results
dissolution
primary
porous
structures
fractures,
reformation
newer
structure
conduits
shales.
Nonetheless,
these
changes
mineralogy
weaken
microstructure
rock
bringing
significant
mechanical
properties
shales
implications
wellbore
stability
efficiency.
such
uniaxial
compressive
strength
(UCS),
Young's
modulus,
tensile
saturation
period
increases.
shown
like
bedding
angle
phase-state
having
varying
effect
behavior
Moreover,
caused
creation
reduction
their
can
also
pose
major
risks,
potential
leakage
through
pathways.
How
processes
would
interact
at
field
scale
control
sealing
capacity,
especially
field-scale
addressing
seepage
CO2.
