A Mini project on the design of Waste water treatment plant which gives an easy idea that can be used in small scale as well as large scale.

1. • WELCOME

2. WASTE WATER
TREATMENT
PLANT

3. BATCH MEMBERS
• R.ALDRIN THAMBI
• R.EBEN HUDSON
• M. JEBARSON SAMUEL
• P. SUDHAKAR
GUIDE: Ms M. ABINAYA B.E M.TECH

4. INTRODUCTION
 Wastewater may be defined as the
combination of water carried wastes removed
from residence , institution, commercial and
industrial establishment together with ground
water , surface water and storm water.
 The treatment plant is provided to protect the
public health with the environmental,
economic, social and political concerns

5. IMPURITIES IN WASTE WATER
• Suspended Impurities -remain floating in
waste water .
• Dissolved Impurities -remain dissolved in
waste water just as salt in water
• Collidal Impurities -impurities which
remaining either in solution or in suspension

6. SEQUENCE WORK IN WASTE WATER
TREATMENT
• Collection work - Refuse is collected
separately and sewage is collected separately .
The waste matter should be transported safely
without affecting the near by areas.
• Treatment work -Water treatment
removes contaminants or reduces their
concentration so that the water becomes fit
for its desired end-use.

7. Disposal work -The treated or untreated waste
water is disposed off in various ways by
irrigating fields or discharging into natural water
courses

8. METHODOLOGY
• Screen
• Grit chamber
• Primary clarifier
• Aeration tank
• Secondary clarifier
• Sludge digestion tank
• Sludge drying bed

9. DIAGRAMATIC REPRESENTATION

10. ANALYSIS
TEST TAKEN
• Hardness test
• pH test
• BOD ( Biological Oxygen Demand) test
• TDS (Total Dissolved Solids) test
• TSS (Total Suspended Solids ) test

11. Comparison of test result with standard value
characteristics Waste water
sample
Standard prescribed as per
IS 4764-1973 IS 2490-1974 GOI
Hardness 250 mg/l 200 mg/l 250 mg/l 230 mg/l
Ph 5 - 5.5-9 5.5-9
BOD 350 mg/l 20 mg/l 30 mg/l 30 mg/l
TDS 3570 mg/l 3000 mg/l 3380 mg/l 3380 mg/l
TSS 500 mg/l 30 mg/l 100 mg/l 100 mg/l

12. POPULATION FORECASTING
• Arithmetic increase method is chosen for
forecasting the future population .
• P2040 =2.566 lakhs
• 80% water goes to sewage
• Max quantity of sewage = 0.891m3/sec

13. DESIGN OF TREATMENT UNITS
• SCREEN :A screen is a device with openings
generally of uniform size for removing bigger
suspended or floating matter in sewage
• Design of Screen
• Assume Shape of bar = M.S.Flats
• Clear spacing between bars = 2.5 cm
• Screen is provided of width 0.76m depth 1.5m

14. DISPOSAL OF SCREENING
The screenings contain more than 80% moisture
and the remaining organic and inorganic matter
• The various methods for the disposal of
screenings , which may be classified as
• Burial
• Incineration
• Digestion

15. SCREEN

16. GRIT CHAMBER
• The main purpose of grit chamber is to scour
the lighter particles where the heavier
particles remains settled
Design of Grit Chamber
• Assume horizontal flow type grit chamber
• dimension of grit chambers is 20×2.5×1.5 m
• The grits should be disposed of by dumping or
burying or by sanitary land fill or low lying
areas

17. GRIT CHAMBER

18. PRIMARY CLARIFIER
• The main purpose of primary clarifier is to
remove the suspended organic solids which
are too heavy to be removed as floating
matters and too light to be removed by grit
chambers
• Design of Primary Clarifier
• Assume radial flow circular settling tank
• Number of clarifiers = 2
• Assume detention time = 2 hrs

19. • settling tank Is of 35m diameter and 3.5m
depth with free board of 0.5 m
• the sludges from the primary clarifier is send
to the sludge digestion tank for digestion of
sludge

20. Primary clarifier

21. AERATION TANK
• The purpose of aeration tank is to remove the
suspended colloidal impurities in the waste
water coming out from primary clarifier .
Design of Aeration Tanks
• Assume circular Aeration tank
• Assume BOD in sewage =200mg/lit
• Aeration tank is of 60 m diameter and 3m
depth

22. Aeration tank

23. SECONDARY CLARIFIER
• The purpose of secondary clarifier is to settle the
effluent from the aeration tank .
Design of secondary clarifier
• Assume circular secondary clarifier
• secondary clarifier is of 25 m diameter and 2.5m
depth of tank
Disposal of sludge
• The sludge coming out from the secondary
clarifier are sent to the sludge digestion tank for
digestion and then sent to drying beds

24. Secondary clarifier

25. SLUDGE DIGESTION TANK
• The sludge withdrawn from clarifier contains a lot
of organic matter, and if disposed may
decompose producing foul gases and lot of
pollution and health hazards.
• To avoid such pollution the sludge is stabilized by
decomposing the organic matter under controlled
anaerobic condition and then disposed suitably
after drying on drying beds etc . The process of
stabilization is called sludge digestion and the
tank where the stabilization is carried out is called
sludge digestion tank.

26. Design of sludge digestion tank
• Assume total suspended solid in raw sewage
= 300 mg/l
• Moisture content of sludge =85%
• Assume circular shape
sludge digester tank is of 25 m dia and 7m depth
Disposal of Sludge
The digested sludge from the digestion tank contains
lot of water
In India the water of sludge is removed by drying the
sludge on drying beds

27. Sludge Digestion tank

28. SLUDGE DRYING BED
• Drying of the digested sludge on open beds of
land is called sludge drying beds. A portion of the
moisture , drains through the bed while most of it
is evaporated to the atmosphere
• Design of Sludge drying bed
• Number of beds =35
• Sludge drying beds is of size 10×19
The dried sludge is generally used as manure in our
country .Some time be disposed of by burning

29. Sludge Drying Bed

30. LAYOUT OF WASTE WATER
TREATMENT PLANT

31. CONCLUSION
• The detailed design and layout of waste water
treatment plant was done successfully
• The treated waste water is disposed in to
the Sea after disinfection . The disposed
water is free from biological oxygen demand
content . Hence the aquatic life can be saved

32. •THANK YOU