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FlocFormer - the best floc for every dewatering task
aquen aqua-engineering gmbh
Bauhofstrasse 31
D-38678 Clausthal-Zellerfeld
Germany
www.aquen.de
WASTEWATER RESEARCH & INDUSTRY SUPPORT FORUM , 9th July 2014
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Subjective of the project
- Controllable flocculation process -
benefits: - improvement of dewatering - improvement of separation - maximum utilisation of flocculant
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Common application Municipal waste water sludge dewatering
flocculant: polymer
pump
pump digester
chamber filter press
decanter / centrifuge
Germany: mainly centrifuges but some move back to chamber filter press to get better %DS
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Common application Pathway of conditioning for chamber filter press
polymer
stirred tank
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Common application Pathway of conditioning for chamber filter press
polymer
inline mixer
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Common application Pathway of conditioning for chamber filter press
polymer polymer
pump
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Common application Pathways of conditioning for chamber filter press
polymer
polymer
polymer
buffer tank
inline mixer
pump filter press
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Common application Conditioning for decanter / centrifuge
Polymer
digested sludge
decanter / centrifuge
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0
50
100
150
200
250
300
350
400
0 1000 2000 3000 4000 5000 6000
run length [Pixel]
0
50
100
150
200
250
300
350
400
0 1000 2000 3000 4000 5000 6000
χ =18.4 10 -6
kg 2 s
-2 m
-4 χ =1.87 10 -6
kg 2 s
-2 m
-4
Target: Generation of a specific floc structure adapted to the
dewatering / separation equipment
run length [Pixel]
Floc structure - The key for the dewatering process
χ = filterability [based on the CST (Vesilind, 1988)] Pixel = 40 μm
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0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
I II III IV V VI VII VIII IX X XI XII XIII XIV
T-Mixer 4.5 g/kg TS T-Mixer 5.0 g/kg TS T-Mixer 5.2 g/kg TS T-Mixer 5.3 g/kg TS T-Mixer 6.0 g/kg TS
FlocFormer 4.5 g/kg TS FlocFormer 5.0 g/kg TS FlocFormer 5.2 g/kg TS FlocFormer 5.3 g/kg TS FlocFormer 6.0 g/kg TS
Floc structure - The key for the dewatering process
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I. Network structures
II. Floc Interaction
III. Discrete Flocs IV. a Floc Erosion/
Destruction
IV. b Floc Pelleting =
good dewatering
Flocculation theory: Steps of the flocculation process
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It is not possible
to generate
a specific floc structure
with only one mixing device.
Flocculation reactor development Fundamentals
Inline Mixer n [min-1]
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It is not possible
to generate
a specific floc structure
with only one mixing device.
Flocculation reactor development Fundamentals
Inline Mixer n [min-1]
Requested
floc structure:
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Two step process: 1. Polymer mixing 2. Floc forming
Scheme of FlocFormer
Schlamm / Wasser
Spezifische Flockenstruktur
Polymer
1. Schritt Polymer Einbringung
2. Schritt Flocken Formung
floc structure of common conditioning
floc structure of FlocFormer
pelleting
The rolling motion in the gap between the rotating cone and the case improves the flocs. The sides of the gap remain parallel; width of gap adjustable. The speed of rotation of the cone is adjustable.
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Flow within the gap
(Wimmer 83)
Top pic = slow rotation; bottom pic = faster and better dewatering result
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Floc structure
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FlocFormer application
36 m3/h FlocFormer (5L)
18 m3/h FlocFormer (3L)
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Optimization of screw press
Huber ScrewPress http://www.huber.de/products/sludge-treatment/dewatering/rotamatr-screw-press-ros-3q.html and ISGK Ishigaki Screw Press www.ishigaki.co.jp
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Municipal sludge dewatering optimization of screw press - results
Poly 1
Poly 2
Poly 3
static mixer static mixer static mixer FlocFormer FlocFormer FlocFormer
Digested sludge Note: typically longer HRT in DE and consequently more VSR
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0
5
10
15
20
25
30
(WWTP Graz, Austria –anaerobic digestion)
Municipal sludge dewatering optimization of screw press - results
polymer consumption [kg/t TS] TS [%]
without FlocFormer with FlocFormer
Polyelectrolyte expressed as active ingredient Dewatering without FlocFormer was optimised by the WwTW
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Optimization of decanter centrifuge operation
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Optimization of decanter centrifuge operation
Common dewatering result – conventional poly system without FlocFormer
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Optimization of decanter centrifuge operation (digested sludge)
decanter 1 decanter 2 with FlocFormer
0
2
4
6
8
10
12
14
16
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poly
mer
con
sum
ptio
n (l/
m3
slud
ge)
dekanter 1 dekanter 2 with FlocFormer
0
5
10
15
20
25
DS
dew
ater
ed (%
)
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Optimization of decanter centrifuge operation Westfalia-Separator (WWTP Oelde) – results Effect of changing cone speed and gap
polymer consumption: 6,5 - 7,0 g/kg DS
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Optimization of decanter centrifuge operation
18.0
20.0
22.0
24.0
26.0
28.0
30.0
1 2 3 4 5
[TS
% d
ew
ate
red
slu
dg
e]
TS increasing WWTP Bremen Farge
without FlocFormer
FlocFormer/ flocculant II
FlocFormer/ flocculant I
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Sludge dewatering decanter centrifuge
FlocFormer like Digested sludge
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Optimization of belt filter press
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Optimization of belt filter press
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21.5
22
22.5
23
23.5
24
24.5
25
25.5
26T
S d
ew
ate
red
slu
dg
e [
%]
Excess sludge, WWTP Linz-Unkel, Waste Activated Sludge
without FlocFormer with FlocFormer
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Optimization of Belmer Winkelpresse (belt filter press)
WWTP Olching, Germany, digested sludge
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Optimization of chamber filter press
20.5
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21.5
22
22.5
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23.5
24
24.5
25
25.5
26T
S d
ew
ate
red
[%
]
(WWTP Ratekau, Schleswig Holstein)
without FlocFormer with FlocFormer
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16%
0%
5%
10%
15%
20%
25%
30%
1 2 3 4 5 6 7 8 9 10
Incre
ase
of
fillin
g f
eed
%
runs
(WWTP Colone Wahn)
Optimization of chamber filter press
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Optimization of Bucher press
WWTP Scharzfeld, Germany, 2-week test, conventional digested sludge c58%VS
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49
50
1 2
avera
ge T
S d
ew
ate
red [
%]
0
2
4
6
8
10
12
1 2
avera
ge P
oly
mer
consum
ption
[g/k
g T
S]
original Bucher inline mixer
FlocFormer conditioning
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Municipal sludge dewatering Optimization of TornadoPress, Japan
pump FlocFormer TornadoPress
The Tornado Press is similar to a Screw Press but with a vertical axis
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FlocFormer trials Kyoto and Niigata, Japan
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Municipal sludge dewatering Japan Optimization of TornadoPress operation
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2
4
6
8
10
12
14
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18
20
TS
dew
ate
red
[%
]
0
5
10
15
20
25
30
Poly
mer c
on
su
mp
tion
[g
/kg
TS
]
common process
common process
FlocFormer
FlocFormer WWTP
Kyoto, Japan
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DeSiFloc COD separation for landfill leachate treatment
coagulation
Biological pre-treated leachate
effluentf
COD approx. 3.500 mg/L
COD separation
COD < 200 mg/L
FlocFormer
rotating disc thickener
COD approx. 210 mg/L
Activated carbon to assure <200 mgCOD/L, which is the requirement for discharging to river; better COD removal in the thickener extends the life of the activated-C
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DeSiFloc COD separation for landfill leachate treatment
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Flocculation and separation effort
DeSiFloc COD separation for landfill leachate treatment
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Resume
Important facts for a short payback period 1. Correct positioning of the FlocFormer in the process
FlocFormer should be immediately before the dewaterer/thickener so that the conditioning is not damaged by pumping, etc.
2. Adjustability of the dewatering/separation device
3. Choice of a adequate flocculant
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Thank you !
Contact:
aquen aqua-engineering gmbh Bauhofstrasse 31
D-38678 Clausthal-Zellerfeld Germany
www.aquen.de