this is a preasentation on water waste treatment

1. By srishti rawat

2. Water that has been utilized in some capacity that negatively impacts the
quality of water.
Sewage is a subset of wastewater that is contaminated with feces or urines.

3. Residences (kitchen, bathroom)
Rainfall, Highway drainage
Industrial institution

4. Water (more than 95%)
Pathogens (bacteria, viruses and parasitic worms)
Non-pathogenic bacteria
Organic particles(feces, hair, food, paper fiber, plant materials)
Soluble organic (urea, protein, sugar ,drug)
Inorganic particles (sand, grit, metals, ceramics etc.)
Soluble inorganic (ammonia, hydrogen sulfide, thiosulfates etc.)
Toxins (pesticides, poisons, herbicides etc.)

5.  Delhi Jal Board is responsible for treatment and disposal of waste
water through an efficient network of about 7000 Km of Sewage
lines across Delhi.
 There are 36 SewageTreatment plants at 21 locations

6. S.No. SewageTreatment plants at Capacity(MGD- Million
Gallons per Day)
1 Keshopur Phase I,II,III 72 MGD
2 Okhla Ph I,II,III,IV,V,VI 170 MGD
3 Kondli Ph I,II,III,IV 90 MGD
4 Rithla I,II 80 MGD
5 YamunaVihar I,II 20 MGD
6 Vasantkunj I,II 5MGD
7 Coronation Pillar I,II,III 40 MGD
8 Narela 10 MGD
9 Nilothi 40 MGD
10 Najafgargh 5 MGD
11 Papankalan 20 MGD

7. 12 Dr.Sen Nursing Home Nalla 2.2 MGD
13 Delhi Gate Nalla 2.2 MGD
14 Mehrauli 5 MGD
15 Rohini 15 MGD
16 Ghitorni 5MGD
17 Kapashera 5MGD
18 Commonwealth GamesVillage 1 MGD
19 Bakkarwala 0.66MGD
20 Molarbandh 0.66MGD
21 Timarpur Oxidation Pond 6 MGD
Total 594.72

8. S. No Unsewered areas Total
Sewerage
provided
1.
Unauthorized-
Regularized
567 541
2. UrbanVillage 135 129
3. Resettlement colonies 44 44
4. RuralVillages 189 34
5. Unauthorized colonies 1639 100

9. process of removing contaminants from wastewater, both runoff and
domestic and making it suitable to discharge back into the environment.
Municipal wastewater treatment
Industrial wastewater treatment

10. Physically
a) Total solid (tested by boiling water)
b) Odors
c) Colors
d) Turbidity
Chemically
a. Biological oxygen demand (BOD)
b. Chemical oxygen demand (COD)

11. WastewaterTreatment
 Mechanical (Physical)Treatment
a) Preliminary
b) Primary
 Secondary (Biological)Treatment
 Tertiary (Chemical)Treatment
SludgeTreatment

12. The objective of preliminary treatment is the removal of coarse solids and
other large materials often found in raw wastewater.
Removal of these materials is necessary to enhance the operation and
maintenance of subsequent treatment unit.
Coarse Screening
Grit Removal

13. Removal of large non biodegradable and floating solids (e.g. rags, clothes,
woods, plastics, papers etc.)

14. Grit particles which are smaller than the aperture of the coarse screen will pass
through and may cause abrasive problems to pipes and pumps.
In grit removal process, velocity is so controlled that grit may settle but most
of the organics are retained in suspension.

16. Objective is the removal of settelable organic and inorganic solids by
Sedimentation, and the removal of the material that will float (scum) by
skimming.
Around 25-50% of the incoming BODs, 50-70% of the total suspended solids
and 65% of oil and grease are removed during primary treatment.

18.  BiologicalTreatment
• Secondary treatment is designed to substantially degrade the biological
content of the sewage which are derived from the human waste, food
waste, soaps and detergents etc.
• Aerobic bacteria and protozoa consume biodegradable soluble organic
contaminants (e.g. sugar, fats, short chain carbon molecules etc.) and
binds much of the less soluble fractions into floc.

19. Secondary sedimentation
•Microorganisms must be separated from the treated water by
sedimentation to produce clarified secondary effluent.
•Biological floc is settled out in secondary clarifier and the secondary
sludge is then sent to sludge treatment unit.

21. Purpose is to provide a final treatment stage to further improve the effluent
quality before it is discharged to the receiving environment.
Nutrients removal
Disinfection
• to reduce the number of microorganisms
Chlorination
Ultraviolet radiation
Ozone
Odor control

23. Wastewater may contain high level of nutrients (N or P compounds) which
excessive release to environment may cause eutrophication.
Overgrowth of weeds, algae, blue-green algae (cyanobacteria).
DE oxygenation
Toxins produced by some algae may contaminate drinking water supply.

24. Nitrification
• Biological oxidation of nitrogen from ammonia to nitrate.
I. Ammonia to nitrite using Nitrosomonas
II. Nitrite to Nitrate using Nitrobacter ssp.
DE nitrification (anoxic condition)
• Nitrate is converted into nitrogen gas and released into air.

25. Biologically
• Using Polyphosphate Accumulating Organism (PAOs)
• The process is called “Enhanced biological phosphorus removal”.
By chemical precipitation
• Using salts of irons (e.g. ferric chloride) or aluminium (e.g. alum) or lime.

26. Odor emitted by wastewater treatment are typically an indication of anaerobic
or septic condition.
Generally arises due to hydrogen sulfide.
Controlled by adding iron salts or hydrogen peroxide or calcium nitrate.

27. This process describes the management and disposal of primary and secondary
sludge.
processes involved are
Anaerobic digestion
Composting
De watering

28. Anaerobic bacteria acts on sludge and produces large amount of waste solids
and biogas ( high concentration of methane).
Methane can be used to generate electricity and run few pumps.
Solid waste (containing water) is sent for composting.

29. An aerobic process that involves mixing of wastewater solids with sources of
carbons such as sawdust, straw or woodchips.
Aerobic bacteria digests both wastewater solids and carbon source and
produce large amount of heat.
Resultant solid is then sent for dewatering.

30. Water is removed from solid waste for volume reduction.
Using drying beds
Mechanically filtering often through cloth screens.
Centrifugation.
The sludge is now ready to be used off sites as fertilizers.