Carbon Research,
Journal Year:
2025,
Volume and Issue:
4(1)
Published: Feb. 4, 2025
Abstract
Ammonia
inhibition
poses
a
significant
challenge
to
the
efficient
and
stable
operation
of
anaerobic
digestion
(AD)
systems
by
leading
volatile
fatty
acid
conversion
reduced
methane
production.
This
study
explores
utilization
lignin-based
hydrochar
(LHC)
carbon
quantum
dots
(CQDs)
produced
via
hydrothermal
carbonization
alkali
lignin
alleviate
ammonia
in
AD
processes.
The
results
showed
that
both
LHC
CQDs
help
counter
decline
yield
production
rate
typically
associated
with
inhibition.
Notably,
addition
1
g/L
significantly
increased
24.25%
compared
control
group.
While
limited
adsorption,
its
primary
impact
was
enhancing
direct
interspecies
electron
transfer
(DIET)
through
improved
redox
capacity
promoting
humic
acid-like
organics
formation.
In
contrast,
charge
resistance,
system
capacity.
Optimizing
temperature
250
°C
further
optimized
properties,
boosting
30.53%
at
concentration
3
g/L.
Microbial
community
metabolic
pathway
analyses
indicated
enriched
hydrolytic
acidifying
bacteria,
as
well
DIET-associated
microorganisms,
facilitating
conversion.
process
enabled
sustained
acetoclastic
hydrogenotrophic
methanogenic
pathways,
effectively
mitigating
adverse
effects
high
nitrogen
concentrations.
Graphical
Molecules,
Journal Year:
2025,
Volume and Issue:
30(8), P. 1766 - 1766
Published: April 15, 2025
Anaerobic
digestion
(AD)
is
a
preferred
method
for
food
waste
(FW)
treatment
due
to
its
sustainability
and
potential
production
of
renewable
bioenergy.
However,
the
accumulation
volatile
fatty
acids
(VFAs)
ammonia
often
destabilizes
AD
process,
managing
digestate
byproduct
poses
additional
challenges.
This
study
investigates
use
co-pyrolysis
biochar
synthesized
from
rice
straw
(DRB)
enhance
methane
efficiency.
DRB
addition
increased
cumulative
yield
by
37.1%,
improved
VFA
conversion
efficiency,
achieved
42.3%
higher
NH3-N-removal
rate
compared
control
group.
The
COD-removal
was
68.7%
throughout
process.
Microbial
analysis
revealed
that
selectively
enriched
Fastidiosipila
Methanosarcina,
promoting
direct
interspecies
electron
transfer
(DIET)
yield.
These
findings
highlight
DRB’s
efficiency
support
closed-loop
resource
utilization.
