Anaerobic
digestion
can
produce
biogas
while
treating
waste,
but
the
process
often
has
difficulties
such
as
acid
inhibition
and
ammonia
inhibition.
The
application
of
bioaugmentation
to
anaerobic
solve
these
problems.
Bacillus
subtilis
was
added
regulate
microbial
community
structure
digestion.
Results
indicated
that
1.12
g
had
best
effect,
with
cumulative
hydrogen
methane
yields
reaching
114.00
mL/g
VS
410.84
VS,
respectively,
which
were
35.88%
37.54%
higher
than
control
group.
also
maximum
proportion
methane,
84.68%.
According
analysis,
addition
significantly
changed
structure,
its
relative
abundance
increased
in
production
stage,
thereby
raising
volatile
fatty
acids
(VFAs)
content.
stage.
It
Bacillus,
Methanosarcina,
Limnochordia,
Syntrophomonas,
Lentimicrobium
Hydrogenispora,
enhancing
substrate
decomposition
efficiency
increasing
production.
results
this
study
suggest
help
both
two-stage
processes.
Bioresources and Bioprocessing,
Journal Year:
2025,
Volume and Issue:
12(1)
Published: Jan. 24, 2025
Abstract
This
research
investigated
the
acidogenic
fermentation
(AF)
of
sugar
cane
molasses
in
an
up-flow
anaerobic
sludge
blanket
(UASB)
reactor
for
production
carboxylates.
The
first
step
was
to
assess
optimum
process
temperature
(25,
35
or
55
ºC)
using
two
different
granular
inocula,
one
from
a
brewery
company
(BGS)
and
other
paper
plant
(PGS).
These
experiments
determined
that
most
suitable
carboxylates
25
ºC,
obtaining
higher
bioconversions
(27.3
±
0.3%
PGS
39.2
0.2%
BGS),
despite
low
pH
value
recorded
(4.0-4.2).
Then,
both
inocula
were
tested
UASB
reactors.
As
consequence
operational
conditions
(25
=
5.5-6,
organic
loading
rate
(OLR)
3
g
COD
·L
-1
·d
hydraulic
retention
time
(HRT)
10
d),
microbial
communities
changed
those
typical
biogas
specialised
volatile
fatty
acids
(VFAs).
Indeed,
highest
bioconversion
efficiency
(70.1%)
obtained
with
BGS,
where
uncultured
Eubacteriaceae
family
microorganisms
(56.0%)
prevailed,
enhancing
butyric
acid
(59.5
2.4%w/w).
Consequently,
this
inoculum
used
further
identify
OLR
threshold
should
not
be
exceeded
attain
optimal
production.
6
resulted
decrease
(59.5%).
VFAs
pool
dominated
by
(63.0
1.4%w/w
at
4.5
52.8
2.2%w/w
).
community
became
even
more
specialised,
increasing
presence
Firmicutes
Actinobacteriota
phyla,
proving
imposed
favoured
when
operating
semicontinuously
fed
