66th Vakantiecursus, TU Delft, January 10, 2014
Potential Role of Thermophilic Digestion in
Energy-Neutral Sewage Treatment Plants
“Adaptation Beyond Expectation”
Dara Ghasimi
PhD candidate at TU Delft
Civil Engineering & Geosciences
Sanitary Engineering Section
Promoter: Prof. Jules van Lier (TU Delft)
Supervisor: Dr. ir. Merle de Kreuk (TU Delft)
Supervisor: Dr. ir. Marcel Zandvoort (Waternet)
Challenge the future
1
Challenge the future
2
Application of Fine Sieve For STP Energy Optimization
Biogas (Renewable energy)
Digester
Digestate sludge
Expectation
• Reduction in aeration energy, less sludge, low transportation cost
• Removal efficiency comparable to pre settling tank (removal of inert COD, TS..)
• Onsite Energy Production: Energy Neutral STP @ Low Cost!
Challenge the future
3
Automatic Methane Potential Test System (AMPTS)
Waterbath & Flasks
CO2 Fixing Bottles
Gas Volume Measuring Device
RT=30 days
I/S = 3 & 5 (based on VS)
Challenge the future
4
Inoculum: Non-adapted Seed Sludge
Cumulative CH4 production/((L/gVS)
Mesophilic BMP Test FSF
0.4
0.5
Thermophilic BMP Test FSF
0.4
HNP WWTP
0.3
0.2
0.2
0.3
M-35°C
0.1
0.2 0
0
5
10
15
20
Time (day)
FSF1
FSF2
FSF3
Aerage
25
30
0.1
0
35
Thermophilic BMP Test FSF
Mesophilic
BMP Test Primary sludge
0.1 0.50.4
Cumulative CH4 production (L / g VS)
Cumulative CH4 production (L / g VS)
0.4 0.3
0.5
FSF 1
FSF 2 0.4
0.3
Average
0 0.3
0
5
10
15
20
Time
(days)
DRANCO- (GFT=VFY)
0.2
25
30
0.3
35
0.2
0.2
0.2
T-55°C
0.10.1
Thermophilic BMP Test
0
5
0.4
0.40.3
0.4
0
00
0
5
5
10
10
15
20
15
20
Time (days)
Primary sludge1
Primary sludge2
FSF 1
Primary
Sludge
Primary
sludge3
FSF 2
AverageAverage
25
30
35
25
0.3
Thermophilic BMP Test Primary Sludge
0.4
30
35
0.1
0.1
0
0 0
0
5
Challenge the future
0.4
5
5
Inoculum: 8 months Adapted Seed Sludge
Cumulative CH4 production/(ml/gVS added)
Cumulative CH4 production/(ml/gVS added)
Cumulative CH4 production/(ml/gVS added)
Mesophilic BMP Test FSM (I/S=3)
400
400
400
400
Thermophilic BMP Test FSM (I/S=3)
300
300
M-35°C
200
200
300
200
FSM1
FSM2
FSM3
Average
100
0
0
5
10
15
20
25
Time (day)
30
35
40
45
100
0
50
0
5
10
Thermophilic BMP Test FSM (I/S=3)
100
0
400
0
400
400
FSM1
300
FSM3
Average
300
300
T-55°C
300
5
200
10
15
20
Time (day)
200
25
30
100
100
Thermophilic BMP Test
0
35
200
200
100
0
300
400
Mesophilic BMP Test Toilet paper
0
5
10
15
20
0
5
10
15
20
25
30
Time (day)
25
30
35
35
FSM1
ToiletFSM3
paper1
Toilet
paper
Toilet
paper2
Average
Toilet paper3
40
45
50
Average
40
45
100
0
0
50
0
5
0
5
Thermophilic BMP Test Toilet paper
400
400
Challenge the future
6
10
FSF3
FSF4
FSF1
FSF2
00
00
00
0
0
0
4 2
86
64
Time (day)
0
6
2
0
16
14
12 14
10 12
810
Inoculum:
18 months
Adapted
Seed4 Sludge
Mesophilic
BMP
Test(I/S=0.5)
Test (I/S=3)
Thermophilic BMP
Test (I/S=15)
BMP
Mesophilic
400
400
FSF1
FSF11
FSF2
FSF12
400
200
200
M-35°C
300
100
100
0
00
42 2
46
4
68
6
8 10
8
Time (day)
10 12
10
FSF6
12
12 14
14
14
16
16
40
200
200
200
T-55°C
00
00
22
0
0
664
868
Time (day)
810
10
10 12
12
10
5
10
M-35°C
15
20
Time (day)
200
25
200
Thermophilic BMP Test Toilet paper
4
6
8
10
12
14
16
0
30
35
T-55°C
100
100
2
FSM1
FSM3
Average
300
300
0
1
20
400
FSF6
100
0
44 2
FSF1
FSF11
FSF2
FSF12
12 14
14
Mesophilic
BMP Test (I/S=15)
Thermophilic BMP
Test (I/S=3)
300
4000
30
100
100
100
400
100
0
14
12
10
300
Mesophilic BMP Test (I/S=3)
400
200
8
Mesophilic
BMP Test (I/S=1)
Thermophilic
Test
(I/S=15)
Test(I/S=0.5)
BMP
ThermophilicBMP
400
400
400
Thermophilic BMP Test FSM300
(I/S=3)
300
300
300
2
0
200
Cumulative CH4 production/(ml/gVS added)
Cumulative CH4 production/(ml/gVS added)
00
0
2
0
Cumulative CH4 production/(ml/gVS added)
0
0
2
0
FSF6
0
4 2
64
86
810
300
Challenge the future
10 12
7
12 14
401
30
Thermophilic BMP Test (I/S=1)
400
FSF3
FSF4
300
300
Thermophilic BMP Test FSM (I/S=3)
M-35°C
400
4
200
200
T-55°C
100
100
300
3
FSF1
FSF2
0
2
0
4
2
6
8 6
4
Time (day)
108
12
10
12 14
FSF3
FSF4
0
14
16
0
2
4
6
8
10
12
14
200
2
Thermophilic BMP Test
(I/S=3) BMP Test (I/S=15)
Mesophilic
Mesophilic BMP Test(I/S=0.5)
400
400
FSF11
FSF1
FSF12
FSF2
100
2
300
300
0
200
2000
5
10
M-35°C
15
20
Time (day)
100
100
FSF6
400000
0
300
4
2
2
6
4
4
8
Cumulative CH4 production/(ml/gVS added)
Cumulative CH4 production/(ml/gVS added)
0
Thermophilic BMP Test
(I/S=0.5) BMP Test (I/S=1)
Mesophilic
400
Cumulative CH4 production/(ml/gVS added)
0
Inoculum: 18 months Adapted Seed Sludge
Thermophilic BMP Test (I/S=15)
Mesophilic
Thermophilic BMP Test
(I/S=0.5) BMP Test (I/S=1)
400
400
400
1
300
300
200
200
25
6
6
12
10
10
14
12
12
14
14
16
16
0
FSF11
FSF12
FSF1
2
2
0
Mesophilic BMP Test (I/S=3)
400
400
FSF6
35
100
0
0
30
200
T-55°C
100
100
Thermophilic BMP Test Toilet0 paper
10
8
8
Time (day)
FSM1
FSM3
Average
300
400
4
0
4
6
2
8
4
6
8 6
Time (day)
10
108
12
10
12
Mesophilic
Thermophilic BMP Test
(I/S=3) BMP Test (I/S=15)
Challenge the future
8
FSF2 14
1214
4
1
3
Conclusion
Short Term Test:
Mesophilic Digester More Efficient
Long Term Adaptation:
Thermophilic Outcompetes Mesophilic
Thermophilic Digester:
High Loaded;
Less Footprint;
Efficient Digester For Onsite Energy Recovery From FSF!
Challenge the future
9
??? + !!!
Challenge the future
10
300
200
100
FSM1
FSM3
Average
20
25
Time (day)
30
35
40
45
50
0
mophilic BMP Test Toilet paper
0
5
10
15
Thermophilic BMP T
400
300
200
100
Toilet paper1
Toilet paper3
Challenge the future
11
Challenge the future
12
Why I AM DOING THIS RESEARCH?
• Dutch Water boards AND STPs agreed to have 20% reduction in Energy
Consumption By 2030
• STPs:
Energy Neutral or Surplus Energy
Challenge the future
13
Introduction
• Cellulose makes up about 30-50% of the SS in the sewage
• It mainly originates from the use of toilet paper
(10-14 kg/person/year)
• Degradation of cellulose in the aeration tank is incomplete and requires aeration
energy
• Cellulose separation efficiency in a primairy clarifier is low
(up to 50%; poor settling property fibres)
Challenge the future
14
(Physical-Chemical Characteristics)
Component
FSFs
TS [g/kg]
100-250
VS[g/kg]
90-225
DS [%]
10-25
VS/TS [%]
90
COD [g/kg]
140-360
SCOD [g/kg]
14-36
TN [g/kg]
1400-1900
TP [g/kg]
700-760
Challenge the future
15
Pyrosequencing Results of The Thermophilic and Mesophilic Sludge
Taxonomy
T2-01-2013
[55°C]
T2-03-2013
[55°C]
M2-01-2013
[35°C]
M2-03-2013
[35°C]
Firmicutes
49,0%
10,1%
4,8%
3,0%
0,1%
0,9%
63,0%
69,6%
42,7%
85,5%
0,5%
0,4%
Chloroflexi
0,0%
0,0%
25,3%
20,7%
Archaea Euryarchaeota
1,8%
1,2%
0,3%
0,1%
Bacteroidetes
OP9
Challenge the future
16