Environment International,
Journal Year:
2019,
Volume and Issue:
133, P. 105257 - 105257
Published: Oct. 31, 2019
Hydrothermal
liquefaction
of
sewage
sludge
to
produce
bio-oil
and
hydro-char
unavoidably
results
in
the
production
high-strength
organic
wastewater
(HTLWW).
However,
anaerobic
digestion
(AD)
HTLWW
generally
has
low
conversion
efficiency
due
presence
complex
refractory
organics.
The
present
study
showed
that
granular
activated
carbon
(GAC)
promoted
AD
continuous
experiments,
resulting
higher
methane
yield
(259
mL/g
COD)
compared
control
experiment
(202
COD).
It
was
found
GAC
increased
activities
both
aceticlastic
hydrogenotrophic
methanogens.
molecular
transformation
organics
further
analyzed.
shown
degradation
soluble
microbial
by-products,
fulvic-
humic-like
substances
as
revealed
by
3-dimensional
fluorescence
excitation-emission
matrix
(3D-EEM)
analysis.
Gas
chromatography
mass
spectrometry
(GC-MS)
analysis
resulted
N-heterocyclic
compounds,
acids
aromatic
compounds
less
new
species.
Fourier
transform
ion
cyclotron
resonance
(FT-ICR-MS)
also
nitrogenous
In
addition,
it
improved
removal
oxidized,
nitrogen
content,
double
bond
equivalent
(DBE)
compounds.
Microbial
not
only
concentration,
but
enriched
more
syntrophic
bacteria
(e.g.,
Syntrophorhabdus
Synergistes),
which
were
capable
degrading
a
wide
range
different
including
Furthermore,
profound
effects
on
methanogens
enrichment
Methanothrix
instead
Methanosarcina
observed.
Overall,
mechanism
with
GAC.
Environmental Science & Technology,
Journal Year:
2018,
Volume and Issue:
52(18), P. 10241 - 10253
Published: Aug. 17, 2018
Conductive
materials
(CM)
have
been
extensively
reported
to
enhance
methane
production
in
anaerobic
digestion
processes.
The
occurrence
of
direct
interspecies
electron
transfer
(DIET)
microbial
communities,
as
an
alternative
or
complementary
indirect
(via
hydrogen
formate),
is
the
main
explanation
given
justify
improvement
production.
Not
disregarding
that
DIET
can
be
promoted
presence
certain
CM,
it
surely
does
not
explain
all
observations.
In
fact,
methanogenic
environments
was
only
unequivocally
demonstrated
cocultures
Geobacter
metallireducens
with
Methanosaeta
harundinacea
Methanosarcina
barkeri
and
frequently
sp.
are
detected
improved
driven
systems.
Furthermore,
conductive
carbon
nanotubes
were
shown
accelerate
activity
methanogens
growing
pure
cultures,
where
expected
occur,
hydrogenotrophic
ubiquitous
full-scale
digesters
treating
for
example
brewery
wastewaters,
indicating
important
mechanism
those
This
paper
presents
overview
effect
several
iron-based
carbon-based
CM
bioengineered
systems,
focusing
on
communities'
changes.
Control
assays,
fundamental
elements
support
major
conclusions
experiments,
critically
revised
discussed.
Energies,
Journal Year:
2018,
Volume and Issue:
11(1), P. 107 - 107
Published: Jan. 3, 2018
Anaerobic
digestion
(AD)
is
an
effective
biological
treatment
for
stabilizing
organic
compounds
in
waste/wastewater
and
simultaneously
producing
biogas.
However,
it
often
limited
by
the
slow
reaction
rates
of
different
microorganisms’
syntrophic
metabolisms.
Stable
fast
interspecies
electron
transfer
(IET)
between
volatile
fatty
acid-oxidizing
bacteria
hydrogenotrophic
methanogens
crucial
efficient
methanogenesis.
In
this
interaction,
electrons
are
exchanged
via
redox
mediators
such
as
hydrogen
formate.
Recently,
direct
IET
(DIET)
has
been
revealed
important
route
AD.
Microorganisms
undergoing
DIET
form
electrical
connections
membrane-associated
cytochromes
conductive
pili;
thus,
not
required
exchange.
This
indicates
that
more
thermodynamically
favorable
than
indirect
IET.
Recent
studies
have
shown
materials
(e.g.,
iron
oxides,
activated
carbon,
biochar,
carbon
fibers)
can
mediate
DIET.
attach
to
materials’
surfaces
or
vice
versa
according
particle
size,
biofilms
aggregates.
Different
promote
improve
AD
performance
digesters
treating
feedstocks,
potentially
suggesting
a
new
approach
enhancing
performance.
review
discusses
role
potential
methanogenic
systems,
especially
with
promoting
