EnvironmentAsia
The international journal published by the Thai Society of Higher Education Institutes on Environment
Available online at www.tshe.org/ea/index.html
EnvironmentAsia
9(1) (2016) 77-83
Available
online at www.tshe.org/EA
DOI 10.14456/ea.1473.9
EnvironmentAsia
2 (2009) 50-54
Genotoxicity Assessment of Mercuric Chloride in the Marine Fish Therapon jaruba
Biogas Production from Batch Anaerobic Co-Digestion of Night Soil with Food Waste
Nagarajan Nagarani, Arumugam Kuppusamy Kumaraguru, Velmurugan Janaki Devi
and Chandrasekaran
ArchanaBanjerdkij
Devi
Assadawut
Khanto and Peerakan
Center
for Marine
and Coastal Studies,
SchoolFaculty
of Energy,
Environment
and Natural
Resources,
Department
of Environmental
Engineering,
of Engineering,
Kasetsart
University,
Madurai Kamaraj
University,
Madurai-625021, India
Bangkok
10900, Thailand
Abstract
Abstract
of theofpresent
study
was
to standardize
and to
assess the
predictive
value
of the cytogenetic
The
The aim
objective
this study
is to
investigate
the biogas
production
from
Anaerobic
Co-Digestion
of Night analysis
Soil (NS)
by
Micronucleus
(MN) test
fish experiment
erythrocytes
as conducted
a biomarker
for marine
environmental
with
Food Waste (FW).
The in
batch
was
through
the NS
and FW withcontamination.
a ratio of 70:30Micronucleus
by weight. The
frequency
in evaluated
erythrocytes
wascharacteristic
evaluated in of
andCo-Digestion
genotoxic potential
of a Production.
common chemical
was of
determined
experimentbaseline
is mainly
by the
and Biogas
In addition
food waste
in
fish
experimentally
in aquarium
under
controlled
conditions.
Fish
(Therapon
jaruba)
exposed
was
inflating
the COD exposed
loading from
17,863 to
42,063
mg/l which
is 135 %
increased.
As the
result,were
it shows
thatfor
pH96
has
hrs
to a single
metal (mercuric
chloride).
Chromosomal
determined
as range
micronuclei
frequency
in
dropped
off in heavy
the beginning
of 7-day during
digestion
and it wasdamage
slightlywas
increased
into the
of optimum
anaerobic
fish
erythrocytes.
Significant
increase
MN frequency
waslobserved
of fish has
exposed
to mercuric
condition.
After digestion
of the
biogas in
production
was 2,184
and 56.5 in
% erythrocytes
of methane fraction
obtained
within 31
chloride.
Concentration of
0.25
ppm induced
highest MN
frequency
(2.95(BMP)
micronucleated
cells/1000
cells compared
days of experimentation.
The
investigation
of the
Biochemical
Methane
Potential
and Specific
Methanogenic
Activities
to
1 MNcell/1000
in control
animals).
The study
revealed
thatmLCH
micronucleus
test,and
as an
index
cumulative
(SMA)
were highlycells
observed.
And the
results were
obtained
by 34.55
0.38
gCHof
4/gCODremoval
4-COD/gVSS-d.
exposure,
appears COD
to be removal
a sensitive
model
evaluate
genotoxic
under controlled
While the average
from
the 4 to
outlets
got 92%,
94%, compounds
94 % and 92in%fish
respectively.
However,conditions.
the effluent in
COD concentration was still high and it needs further treatment before discharge.
Keywords: genotoxicity; mercuric chloride; micronucleus
Keywords: anaerobic digestion; methane production; co-digestion; night soil; food waste
1.
Introduction
1. Introduction
aboutgrowth
200 tons
of mercury
and its
In
TheIndia,
economic
has led
rapidly increasing
compounds
are
introduced
into
the
environment
energy consumption (Zhang et al., 2014). Implement
annually
as effluents
industries
(Saffi,
1981).
of renewable
energy from
become
attractive
alternative
Mercuric
chloride
been
used the
in agriculture
as aof
for reducing
fossil has
fuels
through
development
fungicide,
in
medicine
as
a
topical
antiseptic
and
sustainable energy. Through an investigation design
disinfectant,
and
in
chemistry
as
an
intermediate
in
and construction of an anaerobic digester system from
the
production
othertomercury
compounds.
The
locally
availableofwaste
produce of
biogas, methane
contamination
of
aquatic
ecosystems
by
heavy
rich has received intense attention (Cai et al., 2013).
metals
pesticides
increasing
Humanand
excreta
(nighthas
soil)gained
is a good
source attention
of organic
in
recent
decades.
Chronic
exposure
to and
matter
(Yadev,
2010), there
are comprised
of solid
and
accumulation
of
these
chemicals
in
aquatic
biota
liquid phase 0.4 kg/d and 1.5 L/d (Sayed, 2000). The
can
in tissueofburdens
that in
produce
adverse
rapidresult
reproduction
population
Thailand,
night
effects
not
only
in
the
directly
exposed
organisms,
soil has increased resulted in the increased amount
but
also in waste
humanbeing
beings.
municipal
treated. Recently, considering
Fish
provides
suitablehas
model
for monitoring
the energy recovery,a interest
focused
on anaerobic
aquatic
genotoxicity
and
wastewater
quality
digestion (AD) (Zhang et al., 2014).
because
of its ability
to metabolize
xenobiotics
and
To improve
the potential
of biogas
production,
accumulated
pollutants.
A
micronucleus
assay
has
co-digestion of organic wastes could have the potential
been
used
successfully
in
several
species
(De
Flora,
to improve the efficiency of anaerobic digestion process
et
al., 1993,etAl-Sabti
andand
Metcalfe,
The
(Cheerawit
al., 2012)
dilution1995).
with toxic
micronucleus
(MN)
test
has
been
developed
compound, improve balance of nutrients (C/N) and
together
DNA-unwinding
assayset as
synergistic with
effect to
microorganisms (Zhang
al.,
perspective
methods
for
mass
monitoring
of
2011). Locally, available municipal solid waste (MSW)
clastogenicity and genotoxicity in fish and mussels
(Dailianis et al., 2003).
The MN tests have been successfully used as
a measure of genotoxic stress in fish, under both
laboratory and field conditions. In 2006 Soumendra
et al., made an attempt to detect genetic biomarkers
in
two
Labeo
bata
and organic
Oreochromis
such
as fish
foodspecies,
waste (FW),
it has
highly
fraction
mossambica,
by
MN
and
binucleate
(BN)
interest to improve organic loading rate (Khanto
and
erythrocytes
in
the
gill
and
kidney
erythrocytes
Banjerdkij, 2013).
exposed
to thermal
power
discharge
at
The additional
of food
wasteplant
into night
soil resulted
Titagarh
Thermal
Power
Plant,
Kolkata,
India.
in increasing of COD concentration which effect the
The present
studyproduction.
was conducted
to determineof
potential
of biogas
The experiment
the
acute genotoxicity
of found
the heavy
compound
(Makamo
et al., 2013)
the metal
maximum
biogas
HgCl
in
static
systems.
Mercuric
chloride
is toxic,
2
production
obtained from anaerobic batch experiment
solvable
water
hence it can
the 20%
aquatic
conductedinwith
Co-digestion
of penetrate
night soil and
food
animals.
Mutagenic
studies
with
native
fish
species
waste. However, the BOD/COD was still low (0.1) and
represent
an important
effort
in determining2008).
the
indicated hardly
degradable
(Sirivitayaphakorn,
potential
effects
of
toxic
agents.
This
study
was
The additional 30% of food waste into night soil was
carried
out and
to evaluate
use of the
theorganic
micronucleus
interesting
aimed tothe
improve
loading,
test
(MN)
for
the
estimation
of
aquatic
pollution
BOD/COD ratio result in increasing of potential of
using
edible
fish under
conditions.
biogasmarine
production.
Therefore,
the lab
anaerobic
Co-digestion
of night soil with 30% food waste was investigated in
2.
Materials
and
methods
pilot
scale batch
experiment.
The objective of this research was investigated first
2.1.
Collection
with Sample
the characteristic
of Co-digestion of night soil with
food waste. Secondly, base on control parameters such
The fish
species
for and
the other
present
study
as COD,
pH, TP,
TKN,selected
VFA, ALK
solid
were
was
collected
from
Pudhumadam
coast
of
Gulf
of
evaluated. Lastly, the biogas production and methane
Mannar,
Southeast
Coast
of
India.
Therapon
ratio were analyzed.
jarbua belongs to the order Perciformes of the
family Theraponidae. The fish species, Therapon
jarbua (6-6.3 cm in length and 4-4.25 g in weight)
was selected for the detection of genotoxic effect
A. Khanto et al. / EnvironmentAsia 9(1) (2016) 77-83
2. Materials and Methods
2.1. Co-digestion substrates
The raw materials consist of two organic substrates
which were night soil and food waste. The night soil
samples were obtained from construction site located
nearby Nongkhaem Night soil Treatment Plant. Food
waste was obtained from canteen of Suansunandha
University that covers over 50 food makers. The collected
food wastes were considered impurities such as plastic,
metal and glass. These are classified and remove by
collector. The food wastes were ground by adding some
water for dilution reason. Afterward, the Co-digestion
substrates were filled up to 800 l. The digester was
tightly closed with a rubber and transparently screw
cap. To assure the absent oxygen condition, the screw
tap was drench with silicone. Fig. 1 shows preparation
of food waste and Co-digestion sample.
2.2. Experiment design
of H2S produced from wastewater. The damage or loss
of bio-ball resulted in low efficiency of COD removal.
There were a totally of four sampling ports which
divided into two sides: septic (Sep 1, 2) and anaerobic
filter zone (AF 3, 4) to investigate the wastewater
characteristic. The excess 2 bottom sampling ports
installed for sludge drainage. The biogas production was
counted by flow meter BK-G4.The water samples were
fixed by nitric acid and the sediment samples were dried
by air before analysis for the arsenic concentrations.
2.3. Analytical methods
Table 2 shows analytical methods of parameters
such as pH, COD, TKN, TP, ALK, VFA, TS, VS and
VSS. The laboratory was measured by using (APHA,
2012). The test was conducted at the room temperature
that varied from 30-35oC and non pH adjusted within
31 days of the experiment. The biogas production was
determined by flow meter BK-G4 which installed on
the top of the reactor. The proportional of methane and
other production were measured by GC 6890 machine,
which is CO2, CH4 and N2 can be measured.
The batch anaerobic Co-digestion of night soil and
food waste carried out in ratio of 70:30 (Table 1). The
Co-digestion was performed by 800 l anaerobic batch 2.4. Measurement of biogas production
model (Fig. 2). The diameter (D) and height (H) of
digester have been taken as 55 and 110 cm, respectively. The theoretical methane yield was calculated based
It was installed at Nongkhaem Night soil Treatment on Biochemical Methane Potential (BMP) and Specific
Plant. The reactor was comprised of inlet and outlet Methanogenic Activities (SMA) as follows: BMP
Materials
and
Methods
which2.made
from of
poly
ethylene (PE) with a 4 inches assays have been widely used to determine the methane
diameter. Inside, the polyethylene plate was installed yield of Co-digestion substrate (Delrisco, 2011) can
Co-digestion
substrates
in the2.1.
middle
of the reactor
to separate inner space into be expressed as (1). BMP assays are mainly used to
septic and anaerobic filter zones. The solid particle determine the concentration of organic to methane and
raw materials
consistwithin
of twoaorganic
were night
and food
was sunk by The
sedimentation
process
septic substrates
evaluatewhich
the potential
and soil
efficiency
of waste.
the anaerobic
The
night
soil
samples
were
obtained
from
construction
site
located
nearby
Nongkhaem
Night
soil 2011).
zone, while liquid was flown into anaerobic filter zone process with specific wastewater (Moody,
Treatment
Plant.
Food
waste
was
obtained
from
canteen
of
Suansunandha
University
that
covers
over
wherein the microorganism were active within the Through stoichiometric conversation, CH4 production
50filter
foodmedia
makers.
The collected
wastes
as plastic,
metal and
plastic
(bio-ball).
There food
was 95%
ofwere
void considered
is relatedimpurities
to organicsuch
removal;
395 mLCH
4 equals 1 g
glass. 2These
are classified and remove by collector. The food wastes were ground by adding some
3
and 200 m /m specific surface area which provide COD reduction (Speech, 1996). However, methane
water for dilution reason. Afterward, the Co-digestion substrates were filled up to 800 l. The digester
the best condition for attachment in biofilm form. The production can vary by reactor feedstock and due to
was tightly closed with a rubber and transparently screw cap. To assure the absent oxygen condition,
bio-ball was placed into plastic bags due to convenience multiply digester system factors.
the screw tap was drench with silicone. Fig. 1 shows preparation of food waste and Co-digestion
to replace
in case the bio-ball was damaged by corrosion
sample.
Figure 1. Grinding
food
and co-digestion
Figure
1. waste
Grinding
food waste sample
and Co-digestion sample
2.2. Experiment design
78soil and food waste carried out in ratio of 70:30
The batch anaerobic Co-digestion of night
(Table 1). The Co-digestion was performed by 800 l anaerobic batch model (Fig. 2). The diameter (D)
ball was damaged by corrosion of H2S produced from wastewater. The damage or loss of bio-ball
resulted in low efficiency of COD removal. There were a totally of four sampling ports which divided
Figure 2. Schematic of pilot scale anaerobic digester
into two sides: septic (Sep 1, 2) and anaerobic filter zone (AF
3, 4) to investigate the wastewater
characteristic. The excess 2 bottom sampling ports installed for sludge drainage. The biogas
2.3. Analytical methods
A. Khanto
et al. / EnvironmentAsia 9(1) (2016) 77-83
production was counted by flow meter
BK-G4.
Table 2 shows analytical methods of parameters such as
VS and VSS. The laboratory was measured by using (APHA, 20
o
room temperature
Amount of Co-digestion
material that varied from 30-35 C and non pH adjusted
The
560
l biogas production was determined by flow meter BK-G4 wh
The
proportional of methane and other production were measure
69.12 kg (or 240l)
CO2, CH4 and N2 can be measured.
Table 1. Co-digestion ratio
Co-digestion material
Night soil
Food waste
Ratio
70
30
BMP
BMP
BMP
(ml
(ml
(ml
CH
CH
CH
) == Biogas
Biogas
Biogas
(1)
(1)
(1)
××CH
×CH
CH
(%) (1)
4)4)
4=
4 (%)
44(%)
(COD
(COD
(COD
- COD
--COD
COD
)eff)(mg/L)
)(mg/L)
(mg/L)
gCOD
gCOD
gCOD
removed
removed
removed
infinf
inf
effeff
Table
2. Analytical(1)
methods
of parameters
------------------------------------(1)
(1)
Parameters
Methods
pH
pH
Meter
SMA
SMA
assays
assays
have
have
been
beenwidely
widely
widely
evaluates
evaluates
the
the
anaerobic
anaerobic
sludge
sludge
capacity
capacity
convert
convert
an
organic
organic
SMA
assays
have
been
evaluates
the
anaerobic
sludge
capacity
tototo
convert
anan
organic
COD
Closed
Reflux
SMA
assays
have
been
widely
evaluates
the
substrate
substrate
into
into
methane,
methane,
which
which
escapes
escapes
easily
easily
the
the
gas
gas
phase
phase
and
and
reducing
reducing
the
the
chemical
chemical
oxygen
oxygen
substrate
into
methane,
ininin
which
escapes
easily
tototo
the
gas
phase
and
reducing
the
chemical
oxygen
TKN
Macro-Kjeldahl
BMPin
(ml
CH
)capacity
= phase
Biogas
(1)
×(2)
CH
------------(1)
anaerobic
sludge
toshow
convert
an
organic etetet
4liquid
4 (%)
demand
demand
(COD)
(COD)
inin
the
the
liquid
phase
phase
show
as
(2)
(Sinbuathong
(Sinbuathong
al.,
al.,
2007).
2007).
demand
(COD)
the
liquid
show
asas
(2)
(Sinbuathong
al.,
2007).
ALK
Titration
- CODeffeasily
) (mg/L)
gCOD
substrate
intoremoved
methane, in(COD
whichinfescapes
to the
VFA
Titration
gasSMA
phase
and
reducing
the
oxygen
SMA
SMA
(gCH
(gCH
(gCH
COD)
-COD)
COD)
===chemical
gCH
gCH
gCH
COD
-COD
COD demand
------------------------------------(2)
(2)
(2)
444444TP
Ascorbic Acid
SMA
assays
beenshow
widely
evaluates
the anaerobic sludge capacity to convert
an organic
(COD)
ingVSS
the
phase
(2)
gVSS
gVSS
-liquid
-d-ddhave
tas
×
t t×B
×
BB (Sinbuathong
TS
Gravimetric
substrate
into
methane,
in
which
escapes
easily
to
the
gas
phase
and
reducing
the
chemical
oxygen
et al., 2007).
VS
Gravimetric
demand
(COD)
in
the
liquid
phase
show
as
(2)
(Sinbuathong
et
al.,
2007).
3.3.3.
Results
Results
Results
and
and
and
Discussion
Discussion
Discussion
VSS
Gravimetric
(2)
SMA (gCH
-fermentation
COD) = materials
gCH4 - COD
4 fermentation
3.1.
3.1.
3.1.
Characteristic
Characteristic
Characteristic
ofofof
fermentation
materials
materials
2.4.------------Measurement of(2)biogas production
gVSS - d
t×B
As
As
As
shown
shown
shown
ininin
the
the
the
details
details
details
above,
above,
above,
some
some
some
substrates
substrates
substrates
have
have
have
limitation
limitation
limitation
and
and
and
low-efficiency
low-efficiency
low-efficiency
ofof
of yield was calculated based on B
The
theoretical
methane
3. Results
and Discussion
biological
biological
biological
anaerobic
anaerobic
anaerobic
process.
process.
process.
To
To
To
increase
increase
increase
the
the
the
biogas
biogas
biogas
production,
production,
production,
food
food
food
wastes
wastes
wastes
were
were
were
used
used
used
to
to
to
analyze
analyze
analyze
the
the
the
and
Specific
Methanogenic
Activities
(SMA) as
follows: BMP a
3. Results and Discussion
The Co-digestion of night soil with
additional
30%
viability
viability
viability
ofof
of
the
the
the
Co-digestion
Co-digestion
Co-digestion
between
between
between
substrates
substrates
substrates
(Cheerawit
(Cheerawit
(Cheerawit
etetet
al.,
al.,
al.,
2012).
2012).
2012).
In
In
In
this
this
this
study,
study,
study,
the
the
the
additional
additional
additional
determine
the
methane
yield
of
Co-digestion
substrate
food waste (by weight) was experimented in a pilot scale (Delrisco
3.1.ofof
Characteristic
ofexperimented.
fermentation
materials
30%
30%
30%
of
food
food
food
waste
waste
waste
was
was
was
experimented.
experimented.
Table
Table
Table
3
3
shows
3
shows
shows
the
the
the
characteristics
characteristics
characteristics
ofof
of
night
night
night
soil
soil
soil
and
and
and
food
food
waste
waste
wastethe
assaysThe
are
mainly
used
tofood
determine
3.1. Characteristic of fermentation materials
reactor.
additional
of
food
waste
intoconcentration
night soil of organic
from
from
from
various
various
various
experiments.
experiments.
experiments.
potential
and efficiency
of thematter
anaerobic
results
in increasing
the organic
fromprocess
17,863 with
to specific w
Asco-digestion
shown
in the
details
above,
some
substrates
have
limitation
and
low-efficiency
of
The
The
The
co-digestion
co-digestion
of
of
of
night
night
night
soil
soil
soil
with
with
with
additional
additional
additional
30%
30%
30%
food
food
food
waste
waste
waste
(by
(by
(by
weight)
weight)
weight)
was
was
was
experimented
experimented
experimented
stoichiometric
conversation,
CH
production
is
related
to organic
4
As shown
in the
details above,
some the
substrates
have
42,063
mg/l
which
wasused
135%
(2.35
times)
anaerobic
process.
To increase
biogas
production,
food
wastes
were
toorganic
analyze
the increasing
ininin
abiological
apilot
alimitation
pilot
pilot
scale
scale
scale
reactor.
reactor.
reactor.
The
The
The
additional
additional
additional
of
of
of
food
food
food
waste
waste
waste
into
into
into
night
night
night
soil
soil
soil
results
results
results
in
in
in
increasing
increasing
increasing
the
the
the
organic
organic
COD
reduction
(Speech,
1996).
However,
methane
production
c
and
low-efficiency
of biological
anaerobic
from
night
concentration
and this may result in
viability
of17,863
the
Co-digestion
between
substrates
(Cheerawit
et to
al.,
2012).soil
In
this
study,
the
additional
matter
matter
matter
from
from
from
17,863
17,863
to
to
to
42,063
42,063
42,063
mg/l
mg/l
mg/l
which
which
which
was
was
was
135
135
135
%
%
%
(2.35
(2.35
(2.35
times)
times)
times)
increasing
increasing
increasing
from
from
from
night
night
night
soil
soil
soil
multiply
digester
system
factors.
process.
increase
the
biogas production,
food
wastes
higher biogas
production.
Itfood
waswaste
in unidirectional
30%
of foodTo
waste
was
experimented.
Table
3 shows
the characteristics
of night
soiltendency
and
concentration
concentration
concentration
and
and
and
this
this
this
may
may
may
result
result
result
ininin
higher
higher
higher
biogas
biogas
biogas
production.
production.
production.
ItItwas
Itwas
was
ininin
unidirectional
unidirectional
unidirectional
tendency
tendency
ofof
of
were
used experiments.
to analyze the viability of the Co-digestion tendency of (Makamo et al., 2013) which shows 1.2from
various
(Makamo
(Makamo
(Makamo
etetet
al.,
al.,
al.,
2013)
2013)
2013)
which
which
which
shows
shows
shows
1.2-1.5
1.2-1.5
1.2-1.5
times
times
times
increasing
increasing
increasing
ofof
of
organic
organic
organic
matter
matter
matter
byby
by
anan
an
additional
additional
additional
1010
10
%%
%
between
substrates
(Cheerawit
etsoil
al., 2012).
In this study,
1.5 times
increasing
of organic
matter by an additional
The This
co-digestion
of
night
with
additional
30%which
food
waste
(by
weight)
was
experimented
ofof
of
food
food
food
waste.
waste.
waste.
This
This
was
was
was
due
due
due
tototo
the
the
the
high
high
high
COD
COD
COD
concentration
concentration
concentration
which
which
was
was
was
obtained
obtained
obtained
from
from
from
food
food
food
waste
waste
waste
additional
30% of
food
waste was experimented. 10%
food waste.
This was
to the high COD
in athe
pilot
scale
reactor.
The
additional
soilofresults
in increasing
the due
organic
139,061
139,061
139,061
mg/l
mg/l
mg/l
(Limsuk
(Limsuk
(Limsuk
etetet
al.,
al.,
al.,
2011).
2011).
2011). of food waste into night
Table
3 shows
thetocharacteristics
of night
soil135
and%food
concentration
which
from food waste
matter
from
17,863
42,063 mg/l which
was
(2.35 times)
increasing
fromwas
nightobtained
soil
waste
from
various
experiments.
139,061
mg/l
(Limsuk
et
al.,
2011).
concentration
and
this
may
result
in
higher
biogas
production.
It
was
in
unidirectional
tendency
of
Table
Table
Table
3.3.3.
The
The
The
characteristics
characteristics
characteristics
ofofof
Co-digestion
Co-digestion
Co-digestion
ofofof
night
night
night
soil
soil
soil
and
and
and
food
food
food
waste
waste
waste
(Makamo et al., 2013) which shows 1.2-1.5 times increasing of organic matter by an additional 10 %
of food waste. This was due to the
high
COD NS+10%FW
concentration
which
was obtained from food waste
NS
NS
NS
NS+10%FW
NS+10%FW
NS+10%FW
NS+10%FW
NS+10%FW
NS+30%FW
NS+30%FW
NS+30%FW
139,061
mg/l (Limsuk
al., 2011).
cm
Parameter
Parameter
Parameter
Unit
Unit
Unit et100
(Makamo
(Makamo
(Makamo
(Makamo
(Makamo
(Makamo
(Mahawong
(Mahawong
(Mahawong
This
This
This
study
study
study
100etcm
etal.,
etal.,
al.,
2013)
2013)
2013)
etetal.,
etal.,
al.,
2013)
2013)
2013)
etetal.,
etal.,
al.,
2014)
2014)
2014)
Table 3. The characteristics of
of night soil and food waste 19,34455Co-digestion
cm
19,34419,3441/ 1/1/
2/ 2/2/
-42,063
-42,063
-42,063
COD
COD
COD
mg/l
mg/l
mg/l 55 cm
16,516
16,516
16,516
23,200-27,676
23,200-27,676
23,200-27,676
17,863
17,863
17,863
28,276
28,276
28,276
NS
NS+10%FW
NS+10%FW
BOD
BOD
BOD
mg/l
mg/l
mg/l
1,900
1,900
1,900
2,175-2,400
2,175-2,400
2,175-2,400
13,750
13,750
13,750
21,000
21,000
21,000
NS+30%FW
Parameter
(Makamo
(Makamo
(Mahawong
pH
pH
pH
- Unit
-7.40-7.59
7.40-7.59
7.40-7.59
7.45-7.48
7.45-7.48
7.45-7.48
3.93-5.40
3.93-5.40
3.93-5.40
6.8-7.2
6.8-7.2
6.8-7.2
This study
et342-415
al., 2013)
et305-579
al., 2013)
et
al., 2014)
TKN
TKN
TKN
mg/l
mg/l
mg/l
342-415
342-415
305-579
305-579
683-1,103
683-1,103
683-1,103
1,792
1,792
1,792
TP
TP
TP
mg/l
mg/l
mg/l
23.63-24.97
23.63-24.97
23.63-24.97
73.6-83.0
73.6-83.0
73.6-83.0
62
62
62
5555
55
19,344COD
mg/l
16,516
23,200-27,676
17,8631/-42,0632/
mg/l
mg/l
mg/l
asasas
28,276
- -- -900-2,038
900-2,038
900-2,038
1,125
1,125
1,125
VFA
VFA
VFA
COOH
CH
CH
CH
3COOH
3COOH
3mg/l
BOD
1,900
2,175-2,400
13,750
21,000
Alkalinity
Alkalinity
Alkalinity
mg/l
mg/l
mg/l
asasas
CaCO
CaCO
- -- -- 110 cm 402-690
402-690
402-690 Sep 1 2,250
2,250
2,250
pH
-CaCO
7.40-7.59
7.45-7.48
3.93-5.40
6.8-7.2
3 33
AF 4
1/ 1/1/
2/ 2/2/
110
cm
TKN
mg/l
342-415
305-579
683-1,103 Sep 1
1,792
COD
COD
COD
for
for
for
night
night
night
soil
soil
soilCOD
COD
COD
ofofof
Co-digestion
Co-digestion
Co-digestion
NS:FW
NS:FW
NS:FW
(70:30)
(70:30)
(70:30)
AF 4
TP
mg/l
23.63-24.97
73.6-83.0
62
55
mg/l
as
Sep 2and
The
The
The
addition
addition
addition
ofof
of
food
food
food
waste
waste
waste
provided
provided
provided
more
more
more
substrates
substrates
substrates
for
for
for
methanogenesis
methanogenesis
methanogenesis
and
and
improved
improved
improved
the
the
900-2,038
1,125 the
VFA
AF 3
CH3COOH
Sep 2
biogas
biogas
biogas
yield
yield
yield
(Zhang
(Zhang
(Zhang
and
and
and
Jahng,
Jahng,
Jahng,
2012).
2012).
2012).
The
The
The
COD
COD
COD
concentration
concentration
concentration
was
was
was
ininin
the
the
the
proper
proper
proper
range
range
range
for
for
for
biogas
biogas
biogas
AF 3
Alkalinity mg/l as CaCO3
402-690
2,250
production
production
production
without
without
without
external
external
external
energy
energy
energy
by
by
by
anaerobic
anaerobic
anaerobic
condition
condition
condition
indicated
indicated
indicated
more
more
more
than
than
than
1,270
1,270
1,270
mg/l
mg/l
mg/l
1/
2/
COD for nightetsoil
COD
ofThe
Co-digestion
NS:FW
(70:30)
(Tchobanoglous
(Tchobanoglous
(Tchobanoglous
etet
al.,
al.,
al.,
2003).
2003).
2003).
The
The
ratio
ratio
ratio
between
between
between
BOD/COD
BOD/COD
BOD/COD
ininin
this
this
this
experiment
experiment
experiment
was
was
was
0.5
0.5
0.5
which
which
which
indicated
indicated
indicated
easily
easily
easily
degrade
degrade
degrade
range
range
range
between
between
between
ofof
of
0.5-0.8
0.5-0.8
0.5-0.8
(Sirivitayaphakorn,
(Sirivitayaphakorn,
(Sirivitayaphakorn,
2008).
2008).
2008).
The
The
The
ratio
ratio
ratio
obtained
obtained
obtained
ininin
this
this
this
The
addition
of
foodfor
waste
provided
morethan
substrates
for
methanogenesis
and
improved
experiment
experiment
experiment
was
was
was
more
more
more
suitable
suitable
suitable
for
for
anaerobic
anaerobic
anaerobic
process
process
process
than
than
study
study
study
of
of
of
(Makamo
(Makamo
(Makamo
etetet
al.,
al.,
al.,
2013)
2013)
2013)
where
where
where the
biogasFigure
yield
and
Jahng,
2012).
The
COD
concentration
was
in the proper range
for
biogas
2.(Zhang
Schematic
of
pilot
scale
anaerobic
digester
BOD/COD
BOD/COD
BOD/COD
ratio
ratio
ratio
was
was
was
0.1
0.1
0.1
which
which
which
indicated
indicated
indicated
hardly
hardly
hardly
degradable
degradable
degradable
0.2-0.4
0.2-0.4
0.2-0.4
(Tchobanoglous
(Tchobanoglous
(Tchobanoglous
etetet
al.,
al.,
al.,
2003).
2003).
2003).
production
without
external
energy
by
anaerobic
condition
indicated more
than 1,270
mg/l
Figure
2.
Schematic
of
pilot
scale
anaerobic
digester
Therefore,
Therefore,
Therefore,
the
the
the
additional
additional
additional
30%
30%
30%
of
of
of
food
food
food
waste
waste
waste
suitable
suitable
suitable
for
for
for
microorganism
microorganism
microorganism
tototo
degraded
degraded
degraded
the
the
the
organic
organic
organic
(Tchobanoglous
et al.,
2003). The ratio between BOD/COD in this experiment was 0.5 which
2.3. Analytical
methods
indicated
degrade
range between of 0.5-0.8 (Sirivitayaphakorn, 2008). The ratio obtained in this
2.3. easily
Analytical
methods
experiment was
more
suitable
for anaerobic
process
than 79
studysuch
of (Makamo
et al.,TKN,
2013)TP,
where
Table 2 shows analytical
methods
of parameters
as pH, COD,
ALK, VFA, TS,
Table
2
shows
analytical
methods
of
parameters
such
as
pH,
COD,
TKN,
TP,
ALK, VFA,
BOD/COD
ratio
was
0.1
which
indicated
hardly
degradable
0.2-0.4
(Tchobanoglous
et
al.,
2003).
VS and VSS. The laboratory was measured by using (APHA, 2012). The test was conducted
at the TS,
o
matter from 17,863 to 42,063 mg/l which was 135 % (2.35 times) increasing from night soil
concentration and this may result in higher biogas production. It was in unidirectional tendency of
(Makamo et al., 2013) which shows 1.2-1.5 times increasing of organic matter by an additional 10 %
of food waste. This was due to the high COD concentration which was obtained from food waste
139,061 mg/l (Limsuk et al., 2011).
A. Khanto et al. / EnvironmentAsia 9(1) (2016) 77-83
Table 3. The characteristics of Co-digestion of night soil and food waste
NS
(Makamo
et al., 2013)
NS+10%FW
(Makamo
et al., 2013)
NS+10%FW
NS+30%FW
(Mahawong
This study
et al., 2014)
19,344COD
mg/l
16,516
23,200-27,676
17,8631/-42,0632/
28,276
BOD
mg/l
1,900
2,175-2,400
13,750
21,000
pH
7.40-7.59
7.45-7.48
3.93-5.40
6.8-7.2
substrates.
It might
production. TP683-1,103
and TKN were 55,1,792
1792 mg/l which
TKN
mg/lresult in increasing
342-415 the biogas
305-579
were
5 times higher
than a night soil
characteristic (Makamo
The VFA/ALK
TP about 2 andmg/l
23.63-24.97
73.6-83.0
62 et al, 2013).55
ratio was 0.5 which
was higher than the range of 0.3-0.4 which was usually considered favorable
mg/l as
900-2,038
1,125
VFA
CHof
without the risk
acidification. However, above 0.8 inhibit of methanogenesis occurs. The overall
3COOH
Alkalinity
mg/l
as CaCO3 of night
- soil mixing with
- 30%FW were
402-690
2,250conditions.
parameters of
Co-digestion
suitable in anaerobic
1/
2/
The for
additional
waste
into night soil
results
in formation more VFA and thus low pH was
COD
night soilfood
COD
of Co-digestion
NS:FW
(70:30)
Parameter
Unit
occurred in the initial period. The large amount of VFA leads to decrease of solution pH (Zhang et al.,
2007).The
Theaddition
pH is anofimportant
parameter
the growth
microbes during
food waste
providedaffecting
more substrates
for of
methanogenesis
andanaerobic
improved the
fermentation
kept
in
the
range
of
6.8-7.2
(Yadvika
et
al,
2004),
around
7.07.2
(Khalid
etbiogas
al, higher
2011). than a
biogas
yield
(Zhang
and
Jahng,
2012).
The
COD
concentration
was
in
the
proper
range
The addition of food waste provided more 1792 mg/l which were about 2 andfor
5 times
production
without
external
energy
by
anaerobic
condition
indicated
more
than
1,270
mg/l
substrates for methanogenesis and improved the biogas night soil characteristic (Makamo et al, 2013). The VFA/
3.2.
Theand
COD
removal
and
biogas
production
(Tchobanoglous
et
al.,
2003).
The
ratio
between BOD/COD
in this
experiment
which
yield
(Zhang
Jahng,
2012).
The
COD
concentration
ALK ratio
was
0.5 whichwas
was0.5
higher
than the range of
indicated
easilyrange
degrade
of 0.5-0.8
2008).
The
ratio obtained
in this
was
in the proper
for range
biogasbetween
production
without(Sirivitayaphakorn,
0.3-0.4 which was
usually
considered
favorable
without
the 4 sampling
ports
3,039,et2,453,
2,453where
and 3,039
experimentThe
wasCOD
moreconcentration
suitable for anaerobic
process
than(outlets)
study ofwere
(Makamo
al., 2013)
external energy by anaerobic condition indicated more the risk of acidification. However, above 0.8 inhibit
mg/l respectively,
94%,
94% and
92 %degradable
of COD removal
3 days of experiment
(Fig. 3).
BOD/COD
ratio wasor
0.192%,
which
indicated
hardly
0.2-0.4 after
(Tchobanoglous
et al., 2003).
than 1,270 mg/l (Tchobanoglous et al., 2003). The ratio of methanogenesis occurs. The overall parameters of
The highthe
efficiency
of COD
removal
after suitable
3 days offorexperiment
was caused
mainlythe
byorganic
sedimentation
Therefore,
additional
30% of
food waste
microorganism
to degraded
between
BOD/COD
in this
experiment
0.5soil
which
night soil
mixing with(US)
30%and
FW were
process
due to the
major
content ofwas
night
was inCo-digestion
solid particleof
20-1500
(EU),100-200
indicated
easily
degrade
range
between
of
0.5-0.8
suitable
in
anaerobic
conditions.
The
additional
130-520 (Developing country) g/person-d (Makamo et al.,2013) or average 350 g/person-d. The 1,200food
(Sirivitayaphakorn,
2008). indicated
The ratio that
obtained
in this anaerobic
waste intotreatment
night soil
in formation
l of biogas production
the biological
wasresults
also active
as well. more
The VFA
experiment
was was
moreoperated
suitableuntil
for anaerobic
and thus
low pH
was occurred
in the
initial
period. The
experiment
31 days of process
the experiment
in which
according
to 30-60
days
retention
than time
studyofof
(Makamo
et
al.,
2013)
where
BOD/
large
amount
of
VFA
leads
to
decrease
of
solution
conventional anaerobic process (Sirivitayaphakorn, 2008). At the end of digestion process, the pH
CODCOD
ratio removal
was 0.1 which
indicated
hardly
(Zhang
et al.,
2007).
The
is an
important
parameter
efficiency
measured
at degradable
4 sampling ports
(Sep1,
2 and
AF 3,
4) pH
were
96.9
%, 96.8%,
0.2-0.4
(Tchobanoglous
et al., 2003).
Therefore,port
theAF4affecting
the filter
growth
of microbes
during anaerobic
96.9%
and 97% respectively.
The sampling
(Anaerobic
section)
which indicated
as an
additional
of foodshows
waste suitable
for microorganism
fermentation
in the range of
(Yadvika
outlet30%
of reactor
the highest
COD removal efficiency
due tokept
the sedimentation
for 6.8-7.2
large particle
to degraded
the organic
substrates.
It might
in etproduction.
al, 2004), around
7.0 - 7.2 of
(Khalid
et al,
2011).
and biological
anaerobic
treatment
whereresult
the biogas
The installation
Bio-ball
was
increasing
biogas production.
TP95
and%TKN
were
55, in high wastewater treatment efficiency. However,
(25% the
of reactor
volume) with
of void
result
the COD concentration at the end of the experiment is still high 1,273, 1,327, 1,273 and 1,110 mg/l
respectively. Therefore, the effluent needed for further treatment before discharge.
Figure 3. The comparison of biogas and methane production during the experiment.
The cumulative of biogas and methane production for the pilot scale experiment was shown
in Fig. 3. The pilot scale started generating biogas on the 1st day and reached out to 1,005 l in the 4th
80 was 2,184 l within 31 days of the experiment.
day, respectively. The maximum biogas production
A. Khanto et al. / EnvironmentAsia 9(1) (2016) 77-83
CH4
CO2
Figure 4. The relation of CH4 and CO2 from anaerobic digestion
Fig. 4 shows the relation of CH4 and CO2 production from anaerobic digestion reactor during
31 days of the experiment. The proportional of CH4 and CO2 were measured. Methane was generated
at 46.79 % in the beginning of the experiment and was slightly increased to 55.3 % within 18 days of
The cumulative of biogas and methane production
3.2. The COD removal and biogas production
the experiment and reached onto the maximum 56.5 % within 29 days of the experiment. Methane
for
the
pilot scale experiment
was shown
in Fig.
production in this experiment was in the range of 55-65% (Tchobanoglous
et al., 2003).
Contrary
to 3. The
pilot
scale
started
generating
biogas
on
the
1st
day and
the
TheCO
COD
concentration
the
4
sampling
ports
2 production was high in the beginning of the experiment because the reaction
th in the
out toin
1,005
l in the
4 day, respectively.
The
(outlets)
were 3,039,
2,453 and
3,039
mg/l reached
acidogenesis
stage 2,453,
where soluble
organic
transferred
to CO2 result
a higher
percentage
of CO2
maximum
biogas
production
was
2,184
l
within
31
days
respectively,
or
92%,
94%,
94%
and
92
%
of
COD
(Sirivitayaphakorn, 2008) and was slightly decreased until the ends of the experiment. The research
of the
experiment.
removal
after 3 days
experiment
The high
by (Dahunsi
and of
Oranusi,
2013)(Fig.
was 3).
studied
the biogas
production
from food waste mixing with
Fig.
4 shows
theoperating
relationwithin
of CH
and CO 2
efficiency
COD removal
afterwith
3 days
experiment
humanofexcreta
(night soil)
4:1 of
ratio
by weight without
mixing
and the
604days
anaerobic
digestion
reactor
during 31
was of
caused
mainlyThe
by sedimentation
process
to 24production
experiment.
result shows about
56.5due
% and
% of CH4 from
and CO
obtained
from
experiment.
2
days
of
the
experiment.
The
proportional
of
the major
content
of
night
soil
was
in
solid
particle
By adding more food waste might improve the biogas production and methane yield. However, theCH4 and
were measured.
was
generated at 46.79%
20-1500
(EU),100-200
(US)
and 130-520
(Developing
pH drop
due to VFA
obtained
from food
waste resultCO
in 2unconditional
forMethane
anaerobic
microorganism
in thethe
beginning
the experiment
and BMP
was slightly
country)
(Makamo
et al.,2013)
or were
average
mustg/person-d
be considered.
The BMP
and SMA
determined
methaneofproduction
yield. The
fromThe
this 1,200
experiment
was 34.55
mLCH4/gCOD
with
increased
to which
55.3%harmoniously
within 18 days
of BMP
the experiment
350 obtained
g/person-d.
l of biogas
production
removal in
(Cheerawit
obtained
Co-digestion
of foodtreatment
waste: domestic
6.68-61.72
reachedmLCH
onto the4/gCOD
maximum
56.5%
within 29 days of
indicated
thatfrom
the biological
anaerobic
was and
removal
et
al.,
2012).While
SMA
obtained
from
this
experiment
was
0.38
gCH
-COD/gVSS-d
which
higher
production in this
experiment
also active as well. The experiment was operated until the experiment. Methane
4
than
SMA
from
sludge
originating
from
a
brewery
wastewater
treatment
plant
0.128
gCH
4
et al.,
31 days of the experiment in which according to 30-60 was in the range of 55-65% (Tchobanoglous
et al.,
2007). Therefore,
Co-digestion
of night
food
waste
may
Contrary
to thesoil
COand
production
was
high
in
daysCOD/gVSS-d
retention time(Sinbuathong
of conventional
anaerobic
process 2003).
2
have
alternative
municipal
waste
sources
for
biogas
production.
(Sirivitayaphakorn, 2008). At the end of digestion the beginning of the experiment because the reaction
process, the COD removal efficiency measured at 4 in the acidogenesis stage where soluble organic
4. Conclusion
sampling
ports (Sep1, 2 and AF 3, 4) were 96.9%, transferred to CO2 result in a higher percentage of CO2
96.8%, 96.9% and 97% respectively. The sampling (Sirivitayaphakorn, 2008) and was slightly decreased
The resultfilter
of this
studywhich
was clearly
thatasCo-digestion
nightofsoil
food wastes
areresearch
good
until the ofends
theand
experiment.
The
by
port AF4 (Anaerobic
section)
indicated
substrate
for
biogas
production
for
energy
production.
By
addition
of
food
waste
increase
at
2.35
time
biogas
an outlet of reactor shows the highest COD removal (Dahunsi and Oranusi, 2013) was studied the
of COD
loading
improving Co-digestion
is a good
characteristic.
The waste
anaerobic
batch
production
from food
mixing
withexperiment
human excreta
efficiency
due
to the and
sedimentation
for large particle
shows 97 % COD removal efficiency. On the other hand, TKN and TP remained constant due to the
and biological anaerobic treatment where the biogas (night soil) with 4:1 ratio by weight without mixing and
limit of anaerobic treatment conditions. The maximum cumulative biogas production was 2,184 l and
production. The installation of Bio-ball was (25% the operating within 60 days of experiment. The result
56.5 % methane accounted for biogas produced. The optimum of BMP and higher SMA compared
of reactor volume) with 95% of void result in high shows about 56.5% and 24% of CH 4 and CO 2
with industrial substrate which can be indicated successfully implemented of the anaerobic digestion
obtained
from
experiment.
more
wastewater
treatment efficiency.
However,
the COD
from Co-digestion
night soil and
food waste
as a method
of waste
treatment
leadingBy
to adding
utilization
of food
waste
might
improve
the
biogas
production
and
concentration
at
the
end
of
the
experiment
is
still
renewable energy resource. To improve the biogas production and methane yield, more fraction of
methane
yield.
However,
the
pH
drop
due
to
VFA
highnight
1,273,
1,327,
1,273
and
1,110
mg/l
respectively.
soil and food waste such as 65:35 and 60:40 are interested for the further experiment. However,
Therefore, the effluent needed for further treatment obtained from food waste result in unconditional
for anaerobic microorganism must be considered.
before discharge.
81
A. Khanto et al. / EnvironmentAsia 9(1) (2016) 77-83
The BMP and SMA were determined the methane
production yield. The BMP obtained from this
experiment was 34.55 mLCH 4 /gCOD removal in
which harmoniously with BMP obtained from
Co-digestion of food waste: domestic 6.68-61.72
mLCH 4 /gCOD removal (Cheerawit et al., 2012).
While SMA obtained from this experiment was
0.38 gCH4-COD/gVSS-d which higher than SMA
from sludge originating from a brewery wastewater
t r e a t m e n t p l a n t 0 . 1 2 8 g C H 4- C O D / g V S S - d
(Sinbuathong et al., 2007). Therefore, Co-digestion
of night soil and food waste may have alternative
municipal waste sources for biogas production.
Cai T, Park SY, Racharaks R, Li Y. Cultivation of
Nannochloropsis salina using anaerobic digestion
effluent as a nutrient source for biofuel production.
Applied Energy 2013; 108: 486-92.
Cheerawit R, Thunwadee T, Duangporn K, Tanawat R,
Wichuda K. Biogas production from Co-digestion
of domestic wastewater and food waste. Health
and the Environment Journal 2012; 3(2): 1-9.
Dahunsi SO, Oranusi US. Co-digestion of food waste
and human excreta for biogas production. British
Biotechnology Journal 2013; 3(4): 485-99.
Delrisco ML, Normak A, Orupold K. Biochemical
methane potential of different organic wastes and
energy crops from Estonia. Agronomy Research
2011; 9(1): 331-42.
Khalid A, Arshad M, Anjum.M, Mahmood.T, Dawson L.
The anaerobic digestion of solid organic waste.
Waste Management 2011; 31(8): 1737-44.
Khanto A, Banjerdkij P. Methane fermentation of night
soil and food waste mixture. Journal of Clean
Energy Technologies 2013; 1(3): 234-37.
Limsuk S, Peantum P, Petiraksakul A. Biogas production
from food waste added with crude glycerin produced
from biodiesel production. KKU Engineering Journal
2011; 38(2): 101-10.
Mahawong P, Banjerdkij P, Sirivitayapakorn S, Khanto A.
Anaerobic sequencing batch reactor’s performance of
night soil wastewater. Environment Engineer Associate
of Thailand 2014; 13: 247. (In Thai)
Makamo S, Polruang S, Banjerdkit P. Biogas production
using anaerobic process of Nong Khaem night soil
treatment plant. National Convention on Civil
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Moody LB, Burns RT, Bishop D, Sell ST, Spajic R. Using
biochemical methane potential assays to aid in
co- substrate selection for Co-digestion. Applied
Engineering in Agriculture 2011; 27(3): 433-39.
Sayed MKH, Sayed DH. Determination of the mean daily
stool weight, frequency of defecation and bowel transit
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Watts D. Effect of sulfate on the methanogenic activity
of a bacterial culture from a brewery wastewater during
glucose degradation. Journal of Environmental Sciences
(China) 2007; 19(9): 1025-27.
Sirivitayaphakorn S. Wastewater Technology. Bangkok,
Thailand. 2008. (In Thai)
Speech R. Anaerobic biotechnology for industrial wastewater.
Archae Press Neshville, Tennessee, USA. 1996.
Tchobanoglous G, Burton FL, Stensel HD. Wastewater
engineer treatment and reuse. 4th ed. McGraw-Hill, Inc,
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source -separated human faeces for nutrient recycling.
Waste Management 2010; 30: 50-56.
4. Conclusions
The result of this study was clearly that Co-digestion
of night soil and food wastes are good substrate for
biogas production for energy production. By addition
of food waste increase at 2.35 time of COD loading
and improving Co-digestion is a good characteristic.
The anaerobic batch experiment shows 97% COD
removal efficiency. On the other hand, TKN and
TP remained constant due to the limit of anaerobic
treatment conditions. The maximum cumulative biogas
production was 2,184 l and 56.5 % methane accounted
for biogas produced. The optimum of BMP and higher
SMA compared with industrial substrate which can be
indicated successfully implemented of the anaerobic
digestion from Co-digestion night soil and food waste
as a method of waste treatment leading to utilization
of renewable energy resource. To improve the biogas
production and methane yield, more fraction of night
soil and food waste such as 65:35 and 60:40 are
interested for the further experiment. However, the pH
drop must attentive to control in anaerobic process.
In conclusion, the Co-digestion of night soil and food
waste were proper materials for biogas production from
municipal waste.
Acknowledgement
The authors would like to thank the Ministry of
Energy for granting that support by fulfilling this research and
the Faculty of Engineering, Kasetsart University Bangkok,
Thailand for providing us an equipped laboratory.
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Received 7 August 2015
Accepted 22 October 2015
Correspondence to
Assistant Professor Peerakan Banjerdkij
Department of Environmental Engineering,
Faculty of Engineering,
Kasetsart University,
Bangkok 10900,
Thailand
Tel: (66)86-300-9382
E-mail: [email protected]
83