The concept of common effluent treatment plant has been accepted as a solution for collecting, conveying, treating, and disposing of the effluents from the industrial estates. CETP concept helps small and medium scale industries to dispose of their effluents. The effluent include industrial wastewaters and domestic sewage generated from the estate
2. Water
Water scarcity is the major problem that is
faced all across the world. Although 2/3rd of
the earths crust is made up of water but all this
water is not available for drinking
the major part of water that can be consumed
is getting polluted because of human activities
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3. Wastewater Treatment
Plant
Most treatment plants were built to
clean wastewater for discharge into streams
or other receiving waters, or for reuse
The basic function of wastewater treatment is
to speed up the natural processes by
which water is purified
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4. Types of Wastewater
Treatment Plants
There are three types of Wastewater Treatment Plants :-
Effluent Treatment Plants (ETP)
Sewage Treatment Plants (STP)
Common and Combined Effluent
Treatment Plants (CETP)
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5. Management of CETP
schemes
The following aspects of management is to be
consider
Classification of industries
Ownership
Operation and Maintenance
Financial aspects
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6. Technical aspects for
establishment of CETP
schemes
Numbers of technical aspects can be listed
below:-
Collection and conveyance system
Design and treatment alternatives
Disposal of treated effluent
Cost estimation and cost benefit analysis
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7. Basis of CETP designed
CETP is designed on the basis of:
Quality and flow rate of the wastewater
Effluent standard required by CETP
Possibility of recycle and reuse of treated
wastewater
Availability of land, manpower, energy and expertise
in specific treatment methods
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8. What is CETP?
Influent:- Untreated waste water
Effluent:- Treated waste water
Sludge:- Solid part separated from waste
water by CETP
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INFLUENT
CETP
TREATMENT
EFFLUENT
SLUDGE
9. Commom Effluent
Treatment Plant(CETP)
The concept of common effluent treatment plant
has been accepted as a solution for collecting,
conveying, treating, and disposing of the effluents
from the industrial estates
This CETP concept helps small and medium scale
industries to dispose of their effluents
The effluent include industrial wastewaters and
domestic sewage generated from the estate
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10. CETP categories
Homogenous: Industries producing similar goods
in that industrial area are contributing.
E.g.- tanneries, paper etc.
Heterogenous: Industries producing widely
divergent goods are placed together.
E.g.- chemical, dairy, soft drink, canneries,
pharmaceuticals etc.
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11. What is Effluent ?
Liquid waste out of a factory, farm, commercial
establishment, or a household into a water body
such as a river, lake, or lagoon, or a sewer system
or reservoir
Industrial Effluent:- Those materials which
generally discarded from industrial operations or
derived from manufacturing process
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12. Wastewater Treatment
It has been done in 4 major steps:-
Preliminary Treatment
Primary Treatment
Secondary treatment
Tertiary Treatment
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13. Preliminary Treatment
Remove coarse materials that could damage plant
equipment or would occupy treatment capacity
without being treated with the help of Screens
Pretreatment at Industry level:-
Separation of certain wastewater sewer or drains,in
a logical manner,in each industry itself
Eg:- Steam condenser can be taken directly back to
the boiler for reuse
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14. Primary Treatment
Remove various settleable and floatable particles
present in the wastewater
Sand and Grit Removal
Velocity of incoming water is controlled
Allow sand grit and stones to settle
Organic matter within the flow
Avoid damage of pumps and other equipments
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15. Secondary treatment
Remove BOD, dissolved and colloidal suspended
organic matter by chemical action
Organics are converted to stable solids and carbon
dioxide
Chemicals like Alum and polyelectolyte added to
Wastewater
Coagulation and flocculation takes place
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17. Tertiary Treatment
Physical impurity removed by graded filtration
Removal of physical impurity of 250 micron to 50
micron size
It uses Dual Media Filter(DMF) and Activatd Carbon
Filter(ACF)
Post Chlorination
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19. Tests in CETPs
Various tests conducted in CETPs:-
pH test
TDS test
TSS test
BOD test
COD test
Jar test
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20. CETP’s in India
First unit of CETP established at Pali (Rajasthan), in
1983 by RIICO
At the same time, establishment of CETP for
tanneries in Tamil Nadu taken up by state PSU
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21. Advantages of CETP
Small and medium scale industries are not required
to treat their wastewater separately
Investment at personal level is not requirement
Technical expertise is not required
As many industries waste water is coming in CETP
dilution is achieved
Treatment cost is reduced
Assured wastewater treatment hence better control
over pollution.
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22. Limitations of CETPs
CETPs that serve heterogeneous industrial units
will always have to face fluctuations in quantity and
quality of cocktail of effluent
Occupy too much space
Only control 5 parameters(pH,BOD,COD,TDS,TSS)
The mixing of highly complex waste streams, some
of which may be hot and contain chemically active
compounds
Many of the most toxic and persistent components
of chemical waste streams may simply pass
through the CETP unmodified.
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