ETP plant - 1000
m3/day
Design Data
Raw
Effluent Characteristics:
The DAF Process,
UASB Process followed by aerobic
process and tertiary process is designed on the basis of the following
characteristics of raw dairy effluent as furnished by you as indicated below in
Table 1.
Table 1 - Raw Effluent
Parameters (At the inlet of Inlet Channel)
|
Parameter
|
Value
|
|
Flow, m3/day
|
1000
|
|
pH
|
5-11
|
BOD, mg/l
|
1600
- 2000
|
|
COD, mg/l
|
3500
- 4000
|
|
TSS, mg/l
|
500
|
|
Temperature,
deg C
|
30 – 40
|
|
Oil &
Grease, mg/l
|
< 100
|
Treated Effluent Characteristics:
The treated
effluent after DAF System and UASB Process will have characteristics as
mentioned below in Table 2
Table 2 - Ex UASB Reactor
|
Parameter
|
Value
|
|
PH
|
6.5 – 7.5
|
|
Biogas
Production Co-efficient
|
0.35 - 0.40
m3/kg CODr
|
|
Total Biogas
Production
|
950 m3/day
Max.
|
|
BOD, mg/l
|
250
|
|
COD, mg/l
|
600
|
The
anaerobically treated effluent will be further subjected to Aerobic Process
followed by tertiary treatment (PSF, ACF & chlorination). The treated
effluent parameters after Tertiary Process shall be as indicated below in Table
3.
Table 3 – Ex Tertiary Process
(ACF)
|
Parameter
|
Value
|
|
PH
|
6.5 – 8.5
|
|
BOD, mg/l
|
< 30
|
|
COD, mg/l
|
< 250
|
|
TSS, mg/l
|
< 50
|
|
O & G,
mg/l
|
< 10
|
PROCESS DESIGN CONSIDERATIONS
¨
The total flow considered for the ETP plant is 1000 m3/day.
¨ We have proposed preliminary units such as inlet
channel, screen chamber, equalisation tank and DAF unit.
¨ The primary & secondary system includes Neutralisation,
Buffer Tank, UASB Reactor, Gas Handling System, Hopper Bottom Settling Tank, Aeration
Tank, Secondary Clarifier and Sludge Dewatering System which includes Sludge
Sump and Decanter Centrifuge.
¨ The tertiary system includes Hypochlorite addition,
Holding Tank, Pressure Sand Filter and Activated Carbon Filter.
¨
As pH of the raw effluent varies, either alkali or acid will have to be
used for neutralization during process stabilization and commissioning and the
consumption of the same can be reduced gradually. We propose dosing tanks for
dosing of alkali or acid by gravity to the buffer tank.
¨
The treated effluent parameters Ex – Tertiary System will be guaranteed
for the raw effluent parameters mentioned above in the Table 1.
Process Description
The following section provides a brief description of
the process flow diagram and the unit operations involved in the proposed
treatment:
The raw effluent from the dairy plant will enter into Inlet
channel, which is provided with baffles to remove free floating fat
manually. The effluent from inlet channel will enter into Screen Chamber where coarse material in
the effluent will be removed periodically. The effluent from screen chamber
will enter into Equalisation Tank
where any hydraulic as well as organic variations will be dampened. We have
provided submersible mixers in the equalisation tanks for mixing purpose.
The equalised effluent will be then pumped to a DAF
System where chemicals can be dosed from dosing tanks. Air compressor
and high pressure pump is provided for the DAF system. The scum & solids
from the DAF system will be collected in the Sludge Sump for further
dewatering in the Decanter Centrifuge. We
have provided a mixer in the sludge sump for mixing purpose.
The effluent from DAF system will enter into Buffer
Tank where caustic / lime or acid will be dosed by gravity from dosing
tanks if required. Buffer Tank is designed for a specific HRT considering the
recycle of the treated effluent to maintain certain pH of the effluent entering
UASB Reactor and also to maintain certain feed upflow velocity in the UASB
Reactor for mixing purpose.
The effluent from buffer tank will then be pumped to
the proposed UASB Reactor
through a series of distribution pipes. The multiple distribution ensures a
uniform flow of liquid throughout the sludge blanket making maximum use of
available high bacterial population. The liquid rises to the top of UASB
reactor alongwith the biogas generated and also some sludge particles.
A unique three phase separator separates out the
biogas, liquid and the sludge particles. The biogas is allowed to leave through
collecting domes and is carried through a gas header, foam trap, sediment trap
and flame arrestor to gas flare for ultimate flaring to atmosphere. The liquid
overflows through the gutters and the suspended solids then separated are
allowed to settle down in the sludge blanket thereby retaining valuable
bacterial population (attached to the suspended solids).
The anaerobically treated effluent from UASB Reactor
shall then enter by gravity into Hopper Bottom Settling Tank
for settling of any suspended solids carryover from UASB System. The settled
sludge will be taken back to the buffer tank while the overflow from the
settling tank will enter by gravity into Aeration Tank.
The aeration is achieved by means of submersible
aerators which also help in the complete mixing of the contents of the aeration
tank. The activated sludge generated from the A.T will be settled in the Secondary
Clarifier. A part of the settled activated sludge is recycled back to
the aeration tanks for maintaining a desired MLSS concentration, while the
excess sludge is pumped on to the Sludge Sump for further dewatering.
The DAF sludge and excess aerobic
sludge will be collected in Sludge Sump as described above from
where it will be pumped to a Decanter Centrifuge. The dewatered
sludge from the centrifuge can be disposed off while the filtrate will be taken
back to the buffer tank.
The treated effluent from Secondary Clarifier
will be collected in a Holding Tank from where it will be pumped
to Pressure
Sand Filter and Activated Carbon Filter for further tertiary treatment.
The effluent is subjected to desired hypochlorite addition for the removal of
pathogens before subjected to above tertiary system. The effluent after
tertiary treatment can be discharged for final disposal or for the gardening
purpose.
A. Civil Works:
|
Sr. No.
|
Unit
|
Specifications
|
Quantity
|
|
1.
|
Inlet Channel & Screen Chamber
Length, m
Width, m
SWD, m
Free Board, m
MOC
|
10.0
1.0
1.0
0.3
RCC M20
|
1 No.
|
|
2.
|
Equalisation Tank
Length, m
Width, m
SWD, m
Free Board, m
MOC
|
13.0
13.0
3.0
0.3
RCC M20 with pipe railing
|
1 No.
|
|
3.
|
Buffer Tank
Length, m
Width, m
SWD, m
Free Board, m
MOC
|
5.25
5.25
3.0
0.3
RCC M20 with pipe railing
|
1 No.
|
|
4.
|
UASB Reactor
Diameter, m
SWD, m
Free Board, m
MOC
|
14.6
6.0
0.3
Foundation with RCC Raft, PCC Raft, Rubble
Soling & Compacted Sand Filling & Superstructure in RCC M20 and ladder
with 1 m wide walkway around the reactor with MS Pipe Railing of 1m height
and Drain Channel around the reactor & connecting gutter to buffer tank
|
1 No.
|
|
5.
|
Hopper Bottom Settling Tank
Length, m
Width, m
SWD, m
Free Board, m
MOC
|
4.75
4.75
3.00
0.30
RCC M20
|
1 No.
|
|
6.
|
Aeration Tank
Length, m
Width, m
SWD, m
Free Board, m
MOC
|
13.50
13.50
3.00
0.50
RCC M20
|
1 No.
|
|
7.
|
Secondary Clarifier
Diameter, m
SWD, m
Free Board, m
MOC
|
9.0
2.5
0.5
RCC M20
|
1 No.
|
|
8.
|
Sludge Sump
Length, m
Width, m
SWD, m
Free Board, m
MOC
|
5.75
5.75
3.0
0.3
RCC M20 with pipe railing
|
1 No.
|
|
9.
|
Holding Tank
Length, m
Width, m
SWD, m
Free Board, m
MOC
|
7.5
7.5
3.0
0.3
RCC M20 with pipe railing
|
1 No.
|
|
10.
|
MCC / Lab and Chemical Storage Room
|
|
1 No.
|
|
11.
|
Other Foundations For
|
a. Feed Pumps
b. Foam Trap, Biogas Flare
c. DAF and platform
d. Dosing Tanks, PSF and
ACF
e. Decanter Centrifuge
& platform
f. Inserts required in
civil structures
g. Cable trenches, pipe
support
foundations
|
1 Lot
|
|
12.
|
All inserts in civil work
|
|
1 Lot
|
B. Mechanical,
Bought Outs & Instrumentation
|
Sr. No.
|
Unit
|
Specifications
|
Quantity
|
|
1.
|
Bar Screen
Length, m
Depth, m
Bar Width, mm
Bar Depth, mm
Cleaning Mode
MOC
|
1.0
1.0
10.0
10.0
Manual
MSEP
|
1 No.
|
|
2.
|
Mixers in equalisation tanks
Capacity, HP
|
2.00
|
2 Nos.
|
|
3.
|
DAF Feed Pumps
Flow Rate, m3/hr
Head, MWC
Motor Rating / Speed
Type
MOC
|
42.0
10.0
5.0 HP / 2900 RPM
Horizontal Centrifugal Non Clog
C.I.
|
2 Nos.
(1+1)
|
|
4.
|
Complete
DAF system comprising of DAF unit, recycle pump, air compressor, dosing
system comprising of dosing tanks, agitators & dosing pumps etc.
|
Capacity 42 m3/hr
|
1 No.
|
|
5.
|
Dosing Tanks for Acid & Caustic
Capacity, lits
MOC
|
500.0
HDPE
|
2 Nos.
|
|
6.
|
UASB Feed Pumps
Flow Rate, m3/hr
Head, MWC
Motor Rating / Speed
Type
MOC
|
63.0
15.0
7.5 HP / 2900 RPM
Horizontal Centrifugal Non Clog
C.I.
|
2 Nos.
(1+1)
|
|
7.
|
Aerators in aeration tank
Capacity, HP
Type
|
5.0
Submersible
|
2 Nos.
|
|
8.
|
Sludge Recycle Pumps
Flow Rate, m3/hr
Head, MWC
Motor Rating / Speed
Type
MOC
|
30.0
10.0
3.0 HP
/ 2900 RPM
Horizontal
Centrifugal Non Clog
C.I.
|
2 Nos.
(1+1)
|
|
9.
|
Secondary Clarifier Mechanism
Diameter, m
MOC
|
9.0
MSEP
|
1 No.
|
|
10.
|
PSF Feed Pumps
Flow Rate, m3/hr
Head, MWC
Motor Rating / Speed
Type
MOC
|
42.0
30.0
7.5 HP
/ 2900 RPM
Horizontal
Centrifugal Non Clog
C.I.
|
2 Nos.
(1+1)
|
|
11.
|
PSF & ACF
|
MSEP
|
1 No.
|
|
12.
|
Dosing Tank for Hypochlorite
Capacity, lits
MOC
|
100.0
HDPE
|
1 No.
|
|
13.
|
Mixer for Sludge Sump
Capacity, HP
|
2.00
|
1 No.
|
|
14.
|
Decanter Feed Pumps
Flow Rate, m3/hr
Head, MWC
Motor Rating / Speed
Type
MOC
|
8.0
10.0
1 HP /
2900 RPM
Horizontal
Centrifugal Non Clog
C.I.
|
2 Nos.
(1+1)
|
|
15.
|
Decanter Centrifuge
Application
Capacity, m3/hr
MOC
|
DAF & Aerobic Sludge
Dewatering
8.00
M.S.
|
1 No.
|
|
16.
|
Process Piping, Valves and Fittings within battery
limits
|
Piping – M.S. Class B
Valves – C.I Butterfly Wafer
|
1 Lot
|
|
17.
|
Liquid Flow Meter
Location
Range
Type
|
DAF
& UASB Pump Delivery
0 – 42
& 0 – 63 m3/hr
Full
Bore Electro Magnetic
|
2 Nos.
|
|
18.
|
V Notch for flow measurement
|
MSEP
|
1 No.
|
|
19.
|
Pressure Gauges
Location
Range
|
Pump
Delivery
0 - 4
kg/cm2
|
1 Lot.
|
C. Electricals
a. Control Panel Non- Draw Indoor
Type in IP 52 protection.
b.
Local Push
Button Stations, Cabling, Earthing, Bus bars.
c.
All
electricals are of Non Flame Proof Type.
d.
All
motors are considered TEFC with IP 55, Class B Protection.
Notes:
1. Client to supply one point power
connection at ETP during construction, erection & commissioning.
2. DSTS will provide the drive ratings with
individual connected & operating load at
the time of Detail Engineering.
A. UASB System, Biogas Handling System:
|
Sr. No.
|
Unit
|
Specifications
|
Quantity
|
|
1.
|
UASB System comprising of:
a. Influent Header
b. Bottom Distribution System
c. Three Phase Settler
d. Supporting Structure
e. Distribution Line Valves
f. Baffles, Effluent Gutters, etc.
g. Sampling Ports
h. Inspection Manhole
|
Reactor size 14.6 m x 6.0 m SWD
In M.S of suitable size
HDPE - 10 kg/cm2
MSEP
MS with anticorrosive painting
As per Design
In MS
Suitable size
1 Lot.
|
1 Lot
|
|
2.
|
Biogas
Handling System comprising of:
a. Foam
Trap
b.
Sediment Trap
c.
Flame Arrestor
d. Gas
Flare without Ignition
System
|
|
1 No.
|
|
3.
|
Design
, Engineering , Mechanical & Electrical Erection and Commissioning of ETP
|
|
|
1. Site clearance, site development,
motorable access to the site, consolidation of soil if required, fencing and
gate, internal roads and pathways.
2. Supply of required quantity of power at
one point at ETP during construction, erection and commissioning.
3. Supply of water required during
construction, commissioning and for operation, at battery limit specified by
DSTS.
1.
Laboratory chemicals, lab equipment and testing facilities.
2.
Chemicals, Lube Oil, nutrients, anaerobic seed sludge
and necessary man power required for stabilization of process and commissioning of plant.
3.
Lodging and Boarding facilities alongwith communication facilities such
as phone, fax, email will be provided at free of cost to the supervisors,
engineers for supervision on civil works, erection and commissioning.
4.
Secured space / godown for storage of material and hardware and also
security for plant & Machinery, equipment etc.
5.
Necessary facilities for unloading of plant, machinery, equipment etc to
be provided.
6.
All statutory approval from local authorities.
7.
Disposal of screened material, free fat & oil, skimmed oil &
grease, dried sludge cakes from decanter centrifuge. Treated effluent storage
& pumping required for disposal.
1) INLET
Water : Necessary
quantity of water before mobilization of
site and during construction
and operation and to inlet of Foam Trap and dosing tanks with required
pressure.
Power : Necessary and
required power supply
during construction and operation
at ETP.
Effluent : At
the inlet of Inlet channel with characteristics as outlined in Table 1 of
Design Data.
Chemicals : As
per requirement
Anaerobic
Seed Sludge
2) OUTLET
Biogas : From UASB Reactor to Gas Flare
located within 10 m from
UASB Reactor.
Treated : Tertiary Treatment Outlet
Effluent
Utilities
A.
Area Required
App. 1400 – 1500 m2
- Power
Operating Load - 58.00 kWh
Connected Load - 78.14 kWh
- Chemicals / Nutrients
and Seed Sludge
Caustic/Lime - App. 500 kg/day
OR
Hcl Acid - App. 500 lit/day
Alum - App. 350 kg/day
Polyelectrolyte - App. 1.5 – 3.5 kg/day
Anaerobic Seed Sludge - App. 250 m3
Notes:
1. The anaerobic seed sludge requirement will be one time
during process stabilization and commissioning.
2. The acid & alkali requirement will be worked out
as per actual field conditions & after knowing the acidity and alkalinity of the effluent. The
Alum & Polyelectrolyte requirement for DAF will be worked out as per actual field
conditions.
3. The DAP & Urea requirement depends upon N & P
available in the raw effluent and can be minimized if the COD: N: P ratio is
properly maintained.
4. The actual quantities for chemicals such as
Hypochlorite, De-emulsifier etc. will be worked out as per actual field
conditions.
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