Materials,
Journal Year:
2024,
Volume and Issue:
17(18), P. 4609 - 4609
Published: Sept. 20, 2024
This
study
explores
the
utilization
of
municipal
solid
waste
incineration
fly
ash
(MSWIFA)
in
geopolymer
concrete,
focusing
on
compressive
strength
and
heavy
metal
leachability.
MSWIFA
was
sourced
from
a
Shenzhen
plant
pretreated
by
washing
to
remove
soluble
salts.
Geopolymer
concrete
prepared
incorporate
with
washed
or
unwashed
tested
under
different
pH
conditions
(2.88,
4.20,
10.0).
Optimal
achieved
Si/Al
ratio
1.5,
water/Na
10,
sand-binder
0.6.
The
pretreatment
significantly
enhanced
strength,
particularly
alkaline
conditions,
GP-WFA
(washed
MSWIFA)
exhibiting
49.6%
increase
compared
21.3%
GP-FA
(unwashed
MSWIFA).
Additionally,
GP-WFA’s
reached
41.7
MPa,
comparable
that
control
(GP-control)
at
43.7
MPa.
Leaching
tests
showed
acidic
(pH
2.88)
promoted
leaching,
which
increased
over
leaching
time,
while
an
environment
reduced
leachability
metals.
These
findings
highlight
potential
using
promoting
sustainable
construction
practices,
conditions.
Materials,
Journal Year:
2024,
Volume and Issue:
17(6), P. 1431 - 1431
Published: March 21, 2024
The
massive
stockpiling
of
electrolytic
manganese
residue
(EMR)
has
caused
serious
environmental
pollution.
In
this
study,
EMR,
coal
gangue
(CG),
and
fly
ash
(FA)
were
used
as
raw
materials
to
obtain
the
optimal
mix
ratio
based
on
Design-Expert
mixture
design.
effects
activator
modulus,
liquid–solid
(L/S)
ratio,
curing
temperature
mechanical
properties
geopolymers
investigated.
results
showed
that
compressive
strength
prepared
geopolymer
was
12.0
MPa,
28d
leaching
Mn
0.123
mg/L
under
conditions
EMR:CG:FA
=
0.43:0.34:0.23,
L/S
0.9,
a
60
°C,
time
24
h.
This
indicates
is
an
environmentally
friendly
material
with
high
strength.
mineral
composition
mainly
hydrated
calcium
silicate
gel.
addition,
more
stable
new
phase,
MnSiO3,
generated.
Fourier
transform
infrared
(FTIR)
spectrogram
peak
at
1100
m−1
shifted
1112
cm−1,
which
indicated
geopolymerization
reaction
had
occurred.
Through
scanning
electron
microscopy
(SEM)
energy
dispersive
spectrum
(EDS)
analysis,
it
identified
produced
large
amount
amorphous
gelatinous
substances
relatively
dense
structure,
major
elements
being
oxygen,
silicon,
aluminum,
calcium,
sodium.
The
application
of
incineration
fly
ash
(IFA)
sintering
technology
has
brought
a
large
amount
secondary
(SFA)
rich
in
heavy
metals
and
chlorides,
its
treatment
attracted
much
attention.
A
unique
three-step
involving
acid
washing,
metal
precipitation,
chloride
evaporation
recently
been
developed
to
achieve
complete
resource
utilization
SFA.
industrial
test
results
showed
that
the
optimum
liquid/solid
(L/S)
ratio
Ca(OH)2
added
were
2:1
30%,
respectively,
washing
step.
In
precipitation
step,
use
solid
NaOH
precipitant
at
pH
10
was
optimal
for
removal
metals.
For
evaporation,
average
consumption
steam
electricity
each
tonne
filtrate
0.4
t
16.5
kw·h,
respectively.
Furthermore,
environmental
impact
three
steps
evaluated
separately
through
life
cycle
assessment
(LCA)
method
based
on
results.
indicated
stage
had
greatest
whole
process.
Finally,
considering
IFA
ceramics
plant
available
deacidification
waste
solution
heat
flue
gas,
potential
improving
economic
performance
overall
process
technological
innovation
analyzed
using
LCA
costing
(LCC)
method.
optimization
scenario
with
two
innovative
units
performed
better
terms
sustainability,
decreasing
global
warming
by
29.5%
compared
normal
scenario.
LCC
demonstrated
an
value
−8.15
USD/t
more
economically
efficient
than
4.27
USD/t.
Case Studies in Construction Materials,
Journal Year:
2024,
Volume and Issue:
21, P. e03672 - e03672
Published: Aug. 27, 2024
The
construction
industry
is
a
leading
sector
for
coal
ashes
utilization,
including
in
cement
manufacturing
and
soil
stabilization
applications.In
stabilization,
ashes,
alongside
Ordinary
Portland
Cement
(OPC),
are
the
most
commonly
used
materials.However,
environmental
impact
of
particularly
leaching
heavy
metals
from
stabilized
when
exposed
to
rainfall,
remains
underexplored.There
notable
gap
assessing
impacts
this
interacts
with
rainfall
realworld
scenarios.Therefore,
study
aimed
contribute
filling
gap.Accordingly,
study,
peat
was
by
using
fly
ash,
bottom
OPC.The
characterization
mixture
materials,
physicochemical
engineering
properties,
established
studied
first.Following
impact,
simulations
were
conducted
column
leachate
under
different
conditions
seasons
(dry
wet)
response
its
interaction
rainfall.The
analyzed
Inductively
Coupled
Plasma
Mass
Spectrometry
(ICP-MS)
measure
concentrations
metals,
copper
(Cu),
aluminum
(Al),
manganese
(Mn),
iron
(Fe),
zinc
(Zn).Additionally,
Ion
Chromatography
(IC)
employed
determine
major
anions,
fluoride
(F⁻),
chloride
(Cl⁻),
nitrate
(NO₃⁻),
phosphate
(PO₄
3
⁻),
sulfate
(SO₄
2
⁻).The
findings
revealed
complex
chemical
processes
factors
behavior
highlighting
significant
on
patterns.To
conclude,
provides
valuable
contribution
understanding
implications
utilizing
stabilization.
