Page 1
Inventory and Tertiary Treatment of Effluent
from Textile Industries in BangladeshThe use of a new system combining an enhanced
coagulation, flocculation and filtration
M.A.H. BadshaSupervisor:
Prof. J.B. van Lier
Mentor(s):
C.M. Hooijmans
H.A. Garcia Hernandez Delft, April 14, 2015
Page 2
Introduction
Effluent from textile industries is a great concern in
Bangladesh, because
• High TDS
• Chemical dyes
Major impacts:
o Causing health consequences
o Damaging agricultural lands
o Killing aquatic lives
2
Source: http://oecotextiles.wordpress.com/2009/09/01/dyes-synthetic-and-natural/
Page 3
Problem Statement
• Efficient technology to remove color is expensive
• Limited space for up-gradation
• Unplanned expansion of textile industry in rural areas
As a result, integration of a compact, low cost and
efficient technology to remove colour from textile
effluent is desired.
3
Page 4
Existing ETP of Masco Industries Ltd
4
Inlet Collection Tank Aeration Tank
Secondary Clarifier EC Skid DAF unit
Page 5
5
Compact Treatment System
Figure: Schematic of the polishing unit using AFM grains (Dryden Aqua, 2014)
APF- All Poly Floc (mixer of poly aluminum chloride and poly electrolytes)
ZPM- Zeta Potential Mixer (static mixer)
Page 6
Research Questions
What technologies are available and in operation
to treat textile waste-waters in Bangladesh?
What is the colour removal performance of a
treatment system using AFM and APF with
effluent from an existing wastewater treatment
plant at a textile industry?
6
Page 7
Research Objectives
The specific objectives of the proposed study are:
1. Make an overview of the available technologies
2. Study the adsorption capacity of colour by AFM
3. Study the effect of different flow rates on the
performance of the AFM filter media
4. Compare the performance of APF and a conventional
coagulant
5. Study the performance of the local sand against AFM
6. Run a pilot AFM system at Masco Industries Ltd
7
Page 8
Research Methodology
8
Observe the removal rate of colour by adsorption,
coagulation-flocculation and filtration
Sample collection and characterization
Results and Discussion
Conclusions
Batch studies
Inventory Study
Column studies
Pilot study at Masco Ind. Ltd
Page 9
Inventory Study
Poor treatment facility
9
(a) No overflow in the primary clarifier (b) Paddy field surrounded
by ETP (c) No overflow in secondary clarifier (d) No flow meter
Page 10
Inventory Study
Sludge Management
10
(a) Filter press out of operation (b) Limited space for SDB (c) Dry sludge on
SDB (d) Sludge ready to dispose
Page 11
Batch Studies
11
Wastewater Sample AFM grade-1
Adsorption Test Optimum Coagulant Dosage
Page 12
Batch Adsorption Test Result
12
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 10 20 30 40 50 60 70 80 90 100 110
24 hr 48 hr 72 hr Natural Degradation
Rem
ov
al
Eff
icie
ncy
(%
)
AFM Mass (gm)
Page 13
Optimum Dosing of Coagulant “APF”
13
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 1.10 1.20 1.30
Rem
ov
al
Eff
icie
ncy
(%
)
APF Dosage (ml/L)
Page 14
Column StudiesSchematic of the Column Set-up
14
Page 15
Column Set-up at the Lab
15
Page 16
Results of Column Studies(only feed water without coagulation-flocculation)
16
0
20
40
60
80
100
120
140
160
180
200
220
240
260
280
300
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 1 2 3 4 5 6 7 8 9 10 11 12
Thousands
Removal Efficiency Colour Concentration
Filtrate Volume (ml)
Rem
ov
al
Eff
icie
ncy
(%
)
Co
nce
ntr
ati
on
(Pt.
Co
.)
Initial Color = 282 Pt.Co.
Initial Flow Rate = 315 ml/min
Page 17
Effect of Different Flow Rates(fed with supernatant after coagulation-flocculation with APF)
17
0
20
40
60
80
100
120
140
160
180
200
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 5 10 15 20 25 30 35 40 45 50 55 60
Removal % for F1 Removal % for F2 Removal % for F3
Color Concen. (F1) Color Concen. (F2) Color Concen. (F3)
Rem
ov
al
Eff
icie
ncy
(%
)
Time (min)
Co
nce
ntr
ati
on
(P
t.C
o.)
Initial Color = 482 Pt.Co., Supernatant = 184 Pt.Co.
F1 = 120ml/min, F2 = 220ml/min and F3 = 350ml/min
Page 18
Performance of the Column(fed with supernatant after coagulation-flocculation with APF and Aluminium)
18
0
50
100
150
200
250
300
350
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90
Removal % (APF) Removal % (Aluminium)
Color Concen.(APF) Color Concen.(Aluminium)
Rem
ov
al
Eff
icie
ncy
(%
)
Time (min)
Co
nce
ntr
ati
on
(P
t.C
o.)
Initial Color = 572 Pt.Co., Supernatant (using Aluminium)= 382 Pt.Co.,
Supernatant (using APF) = 207 Pt.Co. and Flow Rate = 315ml/min
Page 19
Performance of Sand and AFM (fed with supernatant after coagulation-flocculation with APF)
19
0
20
40
60
80
100
120
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90
Removal % (Sand) Removal % (AFM)
Color Concen.(Sand) Color Concen.(AFM)
Time (min)
Rem
ov
al
Eff
icie
ncy
(%
)
Co
nce
ntr
ati
on
(P
t.C
o.)
Initial Color = 479 Pt.Co., Supernatant = 119 Pt.Co. and Flow Rate = 315ml/min
Page 20
Backwash Efficiency with Fresh Water(fed with supernatant after coagulation-flocculation with APF)
20
0
10
20
30
40
50
60
70
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 10 20 30 40 50 60 70 80 90 100 110 120
Removal % (used AFM media) Removal % (fresh AFM media)
Color Concen.(used AFM) Color Concen.(fresh AFM)
Rem
ov
al
Eff
icie
ncy
(%
)
Time (min)
Co
nce
ntr
ati
on
(P
t.C
o.)
Initial Color = 257 Pt.Co., Supernatant = 64 Pt.Co. and Flow Rate = 315ml/min
Page 21
Pilot Study at Masco Ind. Ltd
21
Filter Tank APF Dosing Pump Storage Tank
Page 22
Result of the Pilot Study
22
0
50
100
150
200
250
300
350
400
450
500
550
600
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 30 60 90 120 150 180 210 240 270
Removal % Color Concentration
Time (min)
Rem
ov
al
Eff
icie
ncy
( %
)
Co
nce
ntr
ati
on
(P
t.C
o.)
Initial Color = 549 Pt.Co. and Flow Rate = 1m3/h
Discharge
Standard
(In-situ coagulation-flocculation and filtration)
Page 23
0
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 15 30 45 60 75 90 105 120 135 150 165 180
Removal % (sludge) Color Concentration
Time (sec)
Rem
ov
al
Eff
icie
ncy
(%
)
Co
nce
ntr
ati
on
(P
t.C
o.)
Backwash Efficiency
23
Flow Rate = 12m3/h
Page 24
Proposed Treatment Scheme
24
AFM System
Page 25
Conclusions
Regarding the overview on the existing treatment technology:
o Illegal discharge of wastewater
o poorly managed and often non-operational
o coloured effluent is being discharged without any tertiary treatment
o Sludge management is important and needs immediate attention
Regarding activated filter media (AFM) and APF dosing:
o The AFM media has no significant adsorption capacity (with and without
APF dosing)
o APF is a good coagulant compared to aluminium
o Performance of local sand is better than AFM filter media
o Coagulation and flocculation followed by a clarifier could be good enough
Regarding AFM system
o Not suitable as a tertiary treatment system to remove color at a textile
industry
25