presentation @ wedc_ghana_paper id 2403_saief manzoor_al-muyeed_islam mamun
TRANSCRIPT
Experience Sharingof
A novel wastewater treatment ecotechnology
to improve environmental sanitation in urban slums.
39th WEDC International Conference | KNUST, Kumasi, Ghana
www.wateraid.org/bangladesh
Present Scenario of Water Supply and sewerage system in Khulna, Bangladesh
KCPA Map
69.50 sq.km
45.65 sq.km
KCC Map
www.wateraid.org/bangladesh
» Population 1.2 million
» Holding : 60,000~60,500
» Family : 1,95,000
» Population Density : 18,000-1,00,0000/km2
» Average family size: 5 to 6
» No. of Slums: 1100
» Population in Slums: 0.18 millions
» Average Annual Rainfall: 1700mm
» Elevation: 2.15m above MSL
Population, Households & Others in KCC
www.wateraid.org/bangladesh
Faecal Sludge Disposal Pattern
Mud
hole
41%
Open drain45%
Carried by
van6%
Car-ried by
sweeper3%
Surface water discharge
5%
No Sanitary Sewer in KCC
Question remains:
What is the
technological
solution?
www.wateraid.org/bangladesh
DWTS : An Ecotechnology
5
DWTS stands for “Decentralized Wastewater Treatment Systems”.
Advantages:► Providing treatment for domestic and industrial wastewater.
► Low primary investment costs.
► Treatment of wastewater flows up to 1000m3 /day.► Tolerant towards inflow fluctuations.
► Reliable and long-lasting construction design.► Low maintenance cost.
www.wateraid.org/bangladesh
Components of DWTS (Primary Treatment)
Gas
Septic tank Anaerobic Baffled Reactors Anaerobic filters
Inlet
Sludge
www.wateraid.org/bangladesh
Components of DWTS (Secondary and Tertiary Treatment)
O2O2 O2 O2O2 O2
Constructed wetland
Polishing Pond/surface flow constructed wetland
Inlet Outlet
www.wateraid.org/bangladesh
Study Area: Peoples Panchtola ColonyTotal Population = 285
Influent rate = 30,000 L/d
Construction cost = 1 USD/L
Maintenance cost = 200 USD/year
Major challenge: Constricted area
Need an Engineering technology
www.wateraid.org/bangladesh
Pre treatment
Primary treatment Secondary treatment Tertiary treatment Reuse
Endure Environmental Sanitation/2nd generation
02 unit 08 unit 01 unit 01 unit
3.35
x2.1
x1.6
7m
3 1x2.
6x1.
67m
3
12.9x4.27x1.75m3
12.9x4.27x1.75m3
1x2.
6x1.
67m
3
04 unit
Cupola Slag25-40 mm and 75-100mm
Canna Indica Phragmytes Australis
Engineering DWTS
www.wateraid.org/bangladesh
Combined Flow Constructed Wetland
• Forces to flow between porous media
Combine flow = Horizontal flow + Vertical flow
Constructed wetlands is a treatment systems that use natural processes to stabilize, sequester, accumulate, degrade, metabolize, and/or mineralize contaminants. • Both horizontal and vertical
direction.• Maximum utilisation of area
• Surface of porous media assists to reduce pollutants
www.wateraid.org/bangladesh
Combined Flow Constructed Wetland
Combine flow = Horizontal flow + Vertical flow
Trea
tmen
t M
echa
nism
Physical
Biological
Chemical
physical filtrationSedimentation
biological uptaketransformation of nutrients by bacteria (both aerobic and anaerobic)plant roots and metabolism
precipitationabsorptiondecomposition
www.wateraid.org/bangladesh
Effluent Result (DWTS)
DWTS Effluent ResultStd
InfluentRemoval Effc. %
BOD5
(mg/
l)
0 50 100 150 200 250 300 350 4004050
38089.4736842105263
DWTS Effluent ResultStd
InfluentRemoval Effc. %
FC (N
/100
ml)
0 1000 2000 3000 4000 5000500
10004600
89.1304347826087
DWTS Effluent ResultStd
InfluentRemoval Effc. %
COD
(mg/
l)
0 1000 2000 3000 4000 5000 6000180200
480096.25
DWTS Effluent ResultStd
InfluentRemoval Effc. %
TSS
(mg/
l)
40150
1830
97.814207650273
2
DWTS Effluent ResultStd
InfluentRemoval Effc. %
Nitra
te (m
g/l)
0 50 100 150 200 250 30057
25087
34.4827586206897
DWTS Effluent ResultStd
InfluentEffc. %
DO (m
g/l)
0 20 40 60 80 100 120 1402.2
6.250.96
129.166666666667
DWTS Effluent ResultStd
InfluentRemoval Effc. %
TDS
(mg/
l)
0 500 1000 1500 2000 2500770
21001900
59.4736842105263
DWTS Effluent ResultStd
InfluentRemoval Effc. %
Phos
phat
e (m
g/l)
0 20 40 60 80 100 120 140 16026
35148
82.4324324324324
www.wateraid.org/bangladesh
Parameter
Unit Bangladesh
Standard
Influent
Concentratio
n
Settler and Baffled Reactor
Anaerobic Baffled Reactor
Combined Flow
Constructed Wetland
Surface Flow Wetland
Overall treatment
efficiency of the system
Effluent
Concentratio
n
Removal %
Effluent
Concentratio
n
Removal %
Effluent
Concentratio
n
Removal %
Effluent
Concentratio
n
Removal %
Removal %
pH 6~9 6.85 7.02 6.99 7.16 7.16BOD5 mg
L-150 381 141 63 69 51 48 30 40 16.6
790
COD mg L-1
200 4800 3072 36 2180 29 1032 53 180 82.56
96
TSS mg L-1
150 1830 600 67 110 82 60 45 40 33.33
98
TDS mg L-1
2100 1900 1860 2 1228 34 1130 8 770 31.86
59
FC N/100ml
1000 4600 3400 26 1600 53 1100 31 500 54.55
89
DO mg L-1
6.25 0.96 1.15 -20 0.9 22 1.32 -47 2.2 -66.6
7
-130
PO4 mg L-1
35 148 131 12 123 6 73 41 26 64.38
82
NO3 mg L-1
250 87 69 21 67 3 63 6 57 9.52 34
Pollutants removal efficiency of DWTS
www.wateraid.org/bangladesh
»No sewerage systems or disposal place.
Pre intervention condition
»Wastewater even sewage and wastes were dumped beside and near about the premises of their residence.
www.wateraid.org/bangladesh
»Blockage of drainage systems and overflow of wastewater during rainy seasons.
Pre intervention condition
»Resulting surface water bodies and groundwater pollution; foul odor were emitted which pollute the environment.
www.wateraid.org/bangladesh
Improved Environment
www.wateraid.org/bangladesh
Household survey results
Good Moderate Bad Good Moderate BadPre Intervene Situation Post Intervene Situation
0.00 %
10.00 %
20.00 %
30.00 %
40.00 %
50.00 %
60.00 %
70.00 %
80.00 %
90.00 %
100.00 %
www.wateraid.org/bangladesh
» DWTS seems to the appropriate choice for wastewater treatment, where sewerage network is limited/absent.
Conclusions
» An appropriate solution of Faecal Liquid Waste Treatment/On-site sanitation.
Thank you
For further info please contact : WaterAid BangladeshHouse 97/B, Road 25, Block-A, Banani, Dhaka-1213+88 02 881 5757
Presented By,Saief Manzoor-Al-Islam
Programme Officer- Engineer
Co-Authors:
Abdullah Al-MuyeedTechnical Advisor- WASH
Zahidul Islam MamunProgramme Manager- Urban WASH