design of sewage treatment plant

1. DESIGN OF UASB BASED TECHNOLOGY FOR
MUNICIPAL SEWAGE(45MLD) OF TIRUPATI
RUPENDRA BABU K M
12785A0115
krupendra12@gmail.com

2. INTRODUCTION
• By the end of 2030, it is accepted that Tirupati population is around
5,75,000.
• The per capita generation of sewage is around 80L/C/d. Hence, a total of
45 MLD of sewage is going to be handled by Tirupati municipality without
causing any impact on human health and environmental damage.
• The current capital cost –effective technology is UASB system although
operation and maintenance costs are minimum similar to conventional
sludge process.

3. LITERATURE REVIEW ON UPFLOW ANAEROBIC
SLUDG BLANKET (UASB)
• The UASB was developed for the treatment of medium and high strength
waste water in 1972.
• In India UASB can be extensively applied for sewage treatment.
• The UASB reactor has a feed inlet distribution system at the bottom and a
three-phase separator at the top.
• The raw influent is distributed over the bottom and mixed with the
anaerobic sludge bed through the inlet system.
• The blanket of anaerobic sludge is maintained in the lower section of the
reactor and the incoming wastewater is forced to percolate upwards
through this blanket.
• Contact between sludge and feed is increased by the Biogas production.
• The sludge and the Biogas are separated from the effluent in the GLSS
separator.
• The absence of mechanical mixing and sludge recirculation improve the
settle ability of the sludge.

4. CONTD…
Advantages of UASB.
• Limited production of stabilized, easily de-waterable excess sludge,
• Low energy consumption,
• Absence of noise and odour nuisance,
• Proven technology ,
• Low initial investment and maintenance cost,
• Stable process
• Low nutrients requirement,
• Methane rich biogas production.

5. OBJECTIVES
The major objective of the present project is:
• To suggest a sustainable municipal sewage treatment plant for tackling
45MLD of sewage generation in tirupati by the year 2030.
• To provide hydraulic design for various components of sewage plant in
general and UASB components in particular.
• To arrive a capital and operation and maintenance cost on unit basis

6. DESIGN PARAMETERS
1. Hydraulic Retention Time (HRT) = 8 – 10 hours
2. Solids Retention Time (SRT) = 30 – 50 days
3. Organic loading on Sludge blanket = 5 – 10 kg.COD/m3
- d
4. BOD/COD removal efficiency = 85%/60 %
5. Inlet points : Minimum 1 point per 3.7 – 4 m2
Floor Area
6. Flow regime : Constant rate by pumping
7. Up-flow Velocity = 0.5 m/hr. ( Average Flow )
= 1.0 m/hr. ( Peak Flow )
8. Sludge production = 0.15 – 0.25 kg. of solids/ kg. BOD
9. Sludge drying time = 12 days ( Monsoon )
= 8 days ( Winter )
= 6 days ( Summer )

7. 10. Gas production = 0.2 to 0.3 m3
/kg.COD removed
11. Gas quality : CH4 = 65 to 68%
CO2 = 30 to 35%
H2S = 0.5 to 1.0%
12. Gas utilization: Boiler fuel
: 1 m3
of gas is equivalent to 1.2 kwh
electricity
13. Post Treatment : Required

8. LAYOUT OF UASB TRETMENT PLANT

9. HYDRAULIC DESIGN OF TREATMENT UNITS
sewer pipe screen chamber

10. Grit chamber wet well and dry well

11. SPLITTER BOX
UASB
REACTOR
SPLITTER BOX
UASB
REACTOR
UASB
REACTOR
UASB
REACTOR

12. UASB polishing unit for UASB
effluent
• UASB

16. MANPOWER
PARAMETER ASP TF WSP MBBR SBR MBR UASB
Total Annual
Manpower O&
M cost, Rs.
Lacs per MLD
0.32 0.28 0.23 0.32 0.33 0..34 0.3

17. ENERGY GENERATION
PARAMETER ASP TF WSP MBBR SBR MBR UASB
BIOGAS
GENERATION
PER CUM
55-70 55-70 NILL NILL NILL NILL 35-50
BIO ENERGY
GENERATION
KWH
25-35 25-35 NILL NILL NILL NILL 20-30

18. conclusion
• Compare to other treatment plants UASB has capital, operation and
maintenance cost minimum.
• BOD and COD removal efficiency- 85%and60%
• Energy generation in the form of methane gas
1.16kwh energy is produced for every 1 kg of cod removal by anaerobic
process.
• Less biomass (sludge) generation.

19. THANK YOU