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BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 1 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
16.08.2011
20
DATE PREPARED BY PRAVIN/HARI
CHECKED BY PUVIARASAN
APPROVED BY BALASUBRAMANIAN
ADHUNIK POWER & NATURAL RESOURCES LIMITED
MP SUPER THERMAL POWER PLANT
PHASE -I (2 x 270 MW)
DESIGN BASIS REPORT
EFFLUENT TREATMENT PLANT
BGR ENERGY SYSTEMS LIMITED ENVIRONMENTAL ENGINEERING DIVISION
443, ANNA SALAI TEYNAMPET, CHENNAI - 600018
PH 044 24326171, FAX 044 24315678 E Mail – [email protected]
AUGUST –2011
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 2 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
CONTENTS
Sr. No Title Page. No.
1.0 Design Philosophy 3
2.0 Process Description & Treatment Scheme For Oily
Wastewater 5
3.0 Oily Wastewater Treatment Scheme 5
4.0 Process Flow Chart For Oily Wastewater Treatment 7
5.0 Technical Specification for Oily Wastewater Treatment 8
6.0 Process Description for CHP Process Wastewater 13
7.0 CHP Process Wastewater Treatment Scheme 13
8.0 Process Flow Chart For CHPWastewater Treatment 14
9.0 Design Philosophy for CHP Wastewater Treatment 15
10.0 Technical Specification for CHP Process Wastewater
Treatment 18
11.0 Process Description For Sludge Wastewater Treatment 20
12.0 Sludge Wastewater Treatment Scheme 20
13.0 Process Flow Chart For Sludge Wastewater Treatment 21
14.0 Technical Specification for Sludge Treatment Stream 22
15.0 Treated Water Quality 26
REFERENCE
Sr. No. Drg. No. Title
1 GID-1675-ME-ETP-XB-
1036 P&I Diagram for Effluent treatment plant
REVISION STATUS
Sr. No. Rev Date Details
1 A 21.07.2011 First Issue for Approval
2 B
16.08.2011 Revised based on DCPL letter no: 3223 dt
11.08.2011
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 3 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
1.0 DESIGN PHILOSOPHY
1.1 Objective:
This document provides basis of design, technical particulars and the design details of
collection and treatment for the oily wastewater and process effluent water.
1.2 Effluent Details:
The table below furnishes the list of effluent generating from various region of power
plant,
A. Oily Wastewater Stream:
Sr.No. Stream Location
1 Fuel oil storage area oily waste water Fuel oil unloading Area
2 Transformeryard area oily wastewater Transformer yard
3 Power house area oily waste water TG building
B. CHPWastewater Stream:
Sr.No. Stream Location
1 Coal stockpile runoff CHP area
2 Coal Handling Plant Waste CHP area
C. Sludge Handling System:
Sr.No. Stream Location
1 PTP Clarifier PTP Area
Boiler Blow down Sump (I & II) in Boiler Area
One (1) number Boiler blow down sump for each unit with two (2) numbers (1W +
1S) blow down transfer pumps will be provided in the boiler area. The blow down water
from the blow down sumps will be transferred to Ash Water Sump by boiler blow down
transfer pumps. Service water will be used for quenching the boiler blow down water.
For Quenching service water will be added in the boiler blow down sump.
B
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 4 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
Back wash waste from SSF
Side stream filtration back wash waste will be collected & stored in sump located in SSF
area. The collected effluent will be transferred to Ash slurry sump by two (2) numbers
(1W + 1S) SSF waste water transfer pumps.
Filter Backwash Waste
Filtration back wash waste will be collected from DMF, ACF, UF Waste from DM Plant,
DMF Back wash waste from PW System& stored in sump. The collected effluent will be
transferred to the Stilling Chamber in PTP by Two (2) numbers (1W + 1S) Filter
back wash waste transfer pumps.
Miscellaneous floor drains
Other miscellaneous building/pump house floor drains will be connected to the nearest
storm water drain.
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 5 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
2.0 PROCESS DESCRIPTION & TREATMENT SCHEME FOR OILY WASTEWATER
2.1 Oily Wastewater Process Description:
2.1.1Transformer Area
In transformer area two (2) sumps will be provided to collect oily waste water during
periods of rainfall. The Sump will have four numbers (2W + 2S) screw pumps to
transfer the effluent to common oily waste retention pit.
2.1.2 Power house Area
In Power house area two (2) sumps will be provided to collect oily effluent generated
from Power house building. This effluent is generated from floor washings, leakage from
pumps, hydraulic couplings, oil leakage from oil burners etc.Oily waste water from this
sump will be pumped to common oily waste retention pit by four numbers (2W + 2S)
of screw pumps.
2.1.3Fuel Oil Handling Area
From the Fuel Oil handling Area, the oily waste is transferred to Common Oil Waste
Retention Pit for further treatment (By others).
3. Oily Wastewater System:
Oily wastewater generated from the various zones will be transferred to common oily
Waste Retention pit to get homogeneous effluent for further treatment. The equalized
effluent will be transferred to oily water separator by Two (2) numbers (1W + 1S) screw
pumps for free oil separation. One (1) x 75 cum oily water separator will be located in
ETP area & will be having the capacity to handle maximum of 1000 ppm of oil in water.
The slop oil from the oily water separator will be collected in slop oil storage tanklocated
in effluent treatment plant. The treated water from Oily water separator will be collected
in treated water collection pit and then transferred to Ash water sump by Two (2)
numbers (1W + 1S) screw pumps. Sludge collected fromoily water separator will be
collected in CPI sludge pit and then transferred to Ash slurry sump by Two (2) numbers
(1W + 1S) vertical centrifugal pump. For sludge pit Two (2) numbers (1W + 1S) Twin
lobe type blowers shall be provided for keeping the sludge in suspension.
B
B
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 6 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
3.1Treatment Scheme
Oily Effluent Transfer Pumps for Power House Area
Oily Effluent Transfer Pumps for Transformer Yard Area
Common Oil Waste Retention Pit
Oil Water Separator-CPI
CPI Feed Pumps
Retention Pit for Treated Water from Oil Water Separator
Oil Water Separator Treated Effluent Transfer Pumps
Slop Oil Storage Tank
CPI Sludge Pit
CPI Sludge Transfer Pumps
CPI Sludge Pit Blowers
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 7 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
4.0 PROCESS FLOW CHART FOR OILY WASTEWATER TREATMENT
CPI Separator
CPI Sludge Pit
Slop Oil
Storage Tank
Treated Water
Retention Pit
Transformer Yard
Oily Wastewater
Sump
Power House Area
Oily Wastewater
Sump
Fuel Oil Storage
Area Oily Waste
Water Sump
Common Oily Waste Retention Pit
Ash Slurry
Sump Oil Disposal
through Drums
Ash Water
Sump
SSF Backwash
Waste
Boiler Blowdown
I & II
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 8 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
5.0 TECHNICAL SPECIFICATION FOR
OILYWASTEWATER TREATMENT
The below table furnishes the technical specifications of oily wastewater sumps and
pumps.
Sr.No Description Tag Number Specification
1.0 Power House area service
oily waste sump OWS-1
(CONSTRUCTION BY
CLIENT)
Quantity 2 No
MOC RCC
Type Under ground, rectangular
with flat bottom.
2.0 Power House area service
oily waste transfer pump
TAOWTP
1/2
Quantity 4 Nos (2W + 2S)
Capacity 40 m3/hr
Type Screw pump
Head Later
Duty Intermittent
Location Outdoor
Fluid to be handled Service waste from power
house area
MOC
Casing 2 % Ni CI to IS 210 FG
260
Rotor SS 316
Stator Nitrile/EPDM
Shaft SS 316
3.0 Transformer yard oily
waste sump OWS-2
(CONSTRUCTION BY
CLIENT)
Quantity 2 No
MOC RCC
Type Under ground, rectangular
with flat bottom.
4.0 Transformer yard oily
waste transfer pump
TYOWTP
1/2
Quantity 4 Nos (2W + 2S)
Capacity 5 m3/hr
Type Screw pump
Head Later
Duty Intermittent
Location Outdoor
B
B
B
B
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 9 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
Fluid to be handled Oily waste from
transformer yard area.
MOC
Casing 2 % Ni CI to IS 210 FG
260
Rotor SS 316
Stator Nitrile/EPDM
Shaft SS 316
5.0 Common oily waste
retention pit OWS-3
(CONSTRUCTION BY
CLIENT)
Quantity 1 No
Capacity 100 m3
MOC RCC
Type
Above ground,
rectangular with flat
bottom.
6.0 CPI Feed Pump CPI 1/2
Quantity 2 Nos(1W + 1S)
Capacity 75 m3/hr
Type Screw pump
Head Later
Duty Intermittent
Location Outdoor
Fluid to be handled Oily waste from common
oily waste retention pit
MOC
Casing 2 % Ni CI to IS 210 FG
260
Rotor SS 316
Stator Nitrile/EPDM
Shaft SS 316
7.0 Oily water separator OWS
Quantity 1 No
Capacity 75 m3/hr(Net)
Type Plate or Tube with counter
flow/cross flow
Oil concentration at inlet 1000 ppm Max.
Oil Concentration in treated
water 10 ppm Max
Suspended solids at inlet 300 ppm Max
Suspended solids in treated
water 20 ppm Max
Angle of inclination of plates 600Max.
B
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 10 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
or tubes
MOC
Body RCC/Carbon Steel/GRP
Plates
or tubes
UV inhibited virgin
FRP/GRP/PVC
8.0 Slop oil storage tank SOST
Quantity 1 No
Type Vertical cylindrical
Capacity 2 m3/hr
MOC Carbon Steel
9.0
Treated water from oily
water separator storage
tank
TWST (CONSTRUCTION BY
CLIENT)
Quantity 1 No
Capacity 50 m3
MOC RCC
Type Above ground rectangular
with flat bottom
10.0
Oily water separator
treated effluent transfer
pump
OWSTETP
1/2
Quantity 2 Nos (1W+1S)
Capacity 100 m3/hr
Type Screw pump
Head Later
Duty Intermittent
Location Outdoor
Fluid to be handled Treated water from oily
water separator
MOC
Casing 2 % Ni CI to IS 210 FG
260
Rotor SS 316
Stator Nitrile/EPDM
Shaft SS 316
11.0 CPI Sludge Pit CPISP (CONSTRUCTION BY
CLIENT)
Quantity 1 No
Type Above ground Rectangular
with flat bottom
Capacity 10 m3
MOC
RCC
B
B
B
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 11 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
12.0 CPI Sludge pit blower CPISPB 1/2
Quantity 2 Nos ( 1W+1S)
Air flow rate considered 0.4 m3/m3/hr of Effluent
Head 0.45 kg/cm2
Sludge pit capacity 10m3
Air flow rate 10 x 0.4 = 4 m3/hr
Type Rotary, Twin lobe
Duty Intermittent
Blower Capacity provided 36 m3/hr
MOC
Casing CI to IS 210 FG 260
Lobes CS to BS 970 , EN9
Forged
Shaft CS to BS 970 , EN9
Forged
13.0 CPI Sludge transfer pump CPISTP 1/2
Quantity 2 Nos (1W+1S)
Capacity 5m3/hr
Service Sludge from oily water
separator
Head Later
Type Vertical centrifugal type
Duty Intermittent
MOC
Casing 2.5 % Ni CI to IS 210 FG
260
Impeller Stainless Steel – Gr.316
Shaft Stainless Steel – Gr.410
14.0 Quenched Boiler blow
down sump I & II BBDS – 1/2
(CONSTRUCTION BY
CLIENT)
Quantity 2 Nos (one for each unit)
Capacity 50 m3 for each
MOC RCC
Type Under ground, rectangular
with flat bottom.
15.0 Boiler blow down transfer
pumps BBTP – 1/2
Quantity Four (4) Nos (two for
each units)
Capacity 50 m3/hr
Head Later
Duty Continuous
B
B
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 12 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
Service Boiler drain waste water
Type Vertical Centrifugal pump
MOC
Casing 2.5 % Ni CI as per IS 210
FG 260
Impeller Stainless Steel – Gr.316
Shaft Stainless Steel – Gr.410
16.0 SSF Backwash waste
water sump SSFSP (By Client)
Quantity 1 No
Capacity 300 m3
MOC RCC
Type Under ground, rectangular
with flat bottom.
17.0 SSF Backwash waste
water transfer pump
SSFWTP –
1/2
Quantity 2 Nos (1W + 1S)
Capacity 150 m3/hr
Head 25mwc
Type Vertical Centrifugal pump
Duty Intermittent
Service Backwash waste from side
stream filtration system
MOC
Casing 2.5 % Ni CI as per IS 210
FG 260
Impeller Stainless Steel – Gr.316
Shaft Stainless Steel – Gr.410
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 13 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
6.0 PROCESS DESCRIPTION FOR CHPPROCESS
WASTEWATER
Process Description for Process Wastewater Stream:
Coal Pile area rainfall run-off is generated due to rainfall on it. Run-off from the coalpiles
may be collected by a Drainage System around the coal pile and led by gravity to aCoal
Particle Settling Basin formed out of a low lying area inside the Plant itself. The coal
Particle Settling Basin will have two chambers, one Operating and OneStandby. When
one chamber will be full, the second chamber will be put into service.The filled in basin
can be cleaned during dry season. The dried solid sludge i.e. coalparticles can be sold or
fed back into the coal handling system.
Coagulant & Alkali dosing system is provided at the inlet of the settling Basin.
TheDecanted Water is collected in a Decanted Water Sump and therefore pumped
fordischarge to the Rainwater Harvesting Pond or Storm Water Drain.
7.0 CHP Process Wastewater Treatment Scheme:
Coal Particle Settling Basin comprises of two (2) compartment of 3750 m3/hr each which
are used to collect the run-off from Coal Pile area. Settled water from the basin will be
collected in Decanted Water Sump of 3750 m3/hr and then it is transferred to Rain
Water Harvesting Pond/ Storm Water Drain by Four (4) numbers (3W + 1S) vertical
centrifugal pump.
Coal Handling Plant Waste System:
Coal Particle Settling Basin
Coagulant Dosing System
Alkali Dosing System
Decanted Water Sump
Decanted Water Transfer Pumps
Coal Handling Plant Waste Collection Pit
Coal Handling Plant Waste Transfer Pumps
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 14 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
8.0 Process Flow Chart for CHP Wastewater Treatment
Coal Pile Area
Coagulant Aid Dosing
System
Storm Water Drain
Coal Particle Settling
basin
Alkali Dosing System
Coal Handling
Plant Waste
Collection Pit
Decanted Water
Sump
Rain Water Harvesting
Pond/Storm Water Drain
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 15 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
9.0 Design Philosophy for CHP Wastewater Treatment
9.1 Coal Stock Pile Runoff
Rainfall run-off from the coal piles shall be collected by a drainage system around the
coal pile and led by gravity to a coal settling pond. The coal settling pond will have two
compartments(one operating and another will be stand by)and will be of suitable design
to allow settlement of suspended coal particles coming out of the coal pile area run-off.
During the heavy rain fall, only initial 60 minutes of rain water will be passed to coal
setting pond and subsequent water will be routed to nearest storm water drain, as it is
not expected to have any significant amount of coal particles. Alkali and Coagulant Aid
dosing shall be provided at the inlet of settling basin.
Coal settling pond will have twin compartments and capacity of each compartment will
be 3750 cu.m
Design Basis:
Suspended solids at inlet : 1000 ppm
Sp.gravity of coal particles : 1.20
Particle density : 750 kg/m3
Particle size to be settled : 50 microns
9.2 Alkali dosing system:
The pH to be maintained is around 7.5.
pH = - log [ H+]
Hence H+= 10 ^ (-7.5) Mol/lt
H+ x OH- = 10 ^ (-14)
OH- = 10 ^ (-6.5) Mol/lt
1 mole of NaOH contains 40 g of NaOH
OH- Concentration as mg/l of NaOH = 10 ^ (-6.5) x 40 x 1000 =0.0126 mg/lt
Hence, for Design Purpose, Consider 1 ppm of NaOH for maintaining 7.5 pH in the
run-off water
B
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 16 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
Sr. No Description Unit Specification
1 Type of pump -
Diaphragm Type
hydraulically operated
metering pump
2 Duty - Intermittent
3 Volume of compartment m3 3750 (Design)
4 Chemical Caustic solution
5 Design Dosing Rate ppm
1(Design)
6 Specific gravity 1.328
7 Solution Concentration(w/w) % 40.0
8
Chemical Dosing
required/compartment
(40% solution)
lts 85
9 Dosing Tank Capacity lts 100
10 Type of tank Vertical rectangular
with flat bottom
11 Dosing Tank Quantity - Two
12 Dosing Tank MOC RCC with epoxy
painting
13 Dosing Pump Capacity
Provided(10% margin) lph 9
14 Number of Pumps - 2 (1W + 1S)
15 Pump Total Head mwc 20 mwc
16 MOC
Wetted parts SS 316
Diaphragm PTFE
17 Dosing Tank Agitator Quantity - 2 / CS with epoxy
painting
18 Location Chemical house for
Coal Rainfall Runoff
B
B
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 17 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
9.3 Coagulant aid dosing system:
Sr. No Description Unit Specification
1 Type of pump -
Diaphragm Type
hydraulically operated
metering pump
2 Duty - Intermittent
3 Flow rate m3 3750 (Design)
4 Chemical Polyelectrolyte solution
5 Design Dosing Rate ppm 1 (Design)
6 Solution Concentration (w/v) % 1
7 Chemical Dosing
required/compartment lts 375
8 Dosing Tank Capacity lts 375
9 Dosing Tank Quantity - Two
10 Dosing Tank MOC CSRL
11 Dosing Pump Capacity Provided lph 420
12 Number of Pumps - 2 (1W + 1S)
13 Pump Total Head mwc 20 mwc
14 MOC
Wetted parts SS 316
Diaphragm PTFE
15 Dosing Tank Agitator Quantity - 2 / SS 316
16 Location Chemical house for
Coal Rainfall Runoff
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 18 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
10.0 TECHNICAL SPECIFICATION FOR
CHP PROCESSWASTEWATER TREATMENT
The below table furnishes the technical specifications of wastewater sumps and pumps.
Sr.No Description Tag Number Specification
1.0 Coal Handling Plant Waste
Collection Pit SP-1
(CONSTRUCTION BY
CLIENT)
Quantity 1 No
Type
Underground,
Rectangular with flat
bottom.
Effective Capacity 250 m3
MOC RCC
2.0 Effluent Transfer Pumps EFTP-1/2
Quantity 2 Nos (1W+1S)
Type Vertical Centrifugal
Location Outdoor
Liquid Handled Coal Handling Plant
Waste
Duty Intermittent
Capacity 250 m3/hr
MOC
Casing 2.5 % Ni CI as per IS
210 FG 260
Impeller Stainless Steel – Gr.316
Shaft Stainless Steel – Gr.410
3.0 Coal Particle Settling
Basin Two compartment SP - 2
(CONSTRUCTION BY
CLIENT)
Quantity 1 No
(Twin compartments)
Capacity/compartment 3750Cu.M for each
compartment
MOC Earthen
Type
Underground,
Rectangular with flat
bottom.
B
B
B
B
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 19 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
4.0 Decanted water Sump DWS (By Client)
Quantity 1 No
Capacity 3750m3
MOC RCC
Service Decanted water from
Coal settling pond
5.0 Decanted water transfer
pumps DWTP – 1/4
Quantity 4 Nos(3W + 1S)
Capacity 100m3/hr
Head Later
Type Vertical centrifugal
Duty Intermittent
Service Decanted water
MOC
Casing 2.5 % Ni CI as per IS
210 FG 260
Impeller Stainless Steel – Gr.316
Shaft Stainless Steel – Gr.410
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 20 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
11.0 PROCESS DESCRIPTION FOR SLUDGE WASTEWATER
TREATMENT
Process Description:
Sludge from PTP clarifier will be collected in sludge sump. The sludge will be pumped to
sludge thickener & the thickened sludge from thickener under flow will be collected in
Thickened Sludge Collection Pit and then pumped to centrifuge for dewatering the
sludge. Thickener Supernatant will be collected to Thickened Supernatant Collection
Sump. This Supernatant water is transferred to Stilling Chamber for further treatment.
From the centrifuge, the sludge is dumped by means of trucks.Poly is been dosed in the
centrifuge inlet to increasing the efficiency of sludge thickening. The filtrate from
centrifuge is been sent back to thickener for further treatment.
12.0 Sludge Wastewater Treatment Scheme:
Based on the treatment philosophy, the ETP recycle plant will have the following:
Sludge Thickener
Thickened Sludge Collection Pit
Thickener Supernatant Collection Sump
o Thickener Supernatant Collection Pump
Centrifuge Feed Pump
Centrifuge
Poly Dosing Tank with Agitator
o Poly Dosing Pump
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 21 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
13.0 PROCESS FLOW CHART FOR
SLUDGE WASTEWATER TREATMENT
Sludge Thickener
Thickened Sludge
Collection Pit
Centrifuge
Sludge Dumped
through trucks
Poly Dosing System
Thickened
Supernatant
Collection Sump
Stilling Chamber
(Raw water System)
Sludge from PTP
Area B
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 22 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
14.0 TECHNICAL SPECIFICATION FOR SLUDGE TREATMENT STREAM
Process Wastewater Quantity:
Sludge from PTP Clarifier will be collected sludge sump and pumped into Sludge
Thickener.
The flow to ETP from PTP Sludge Sump = 110 m3/hr
The filtrate from centrifuge will be 75 % of the feed (75 m3/hr),
Therefore 75 % of 75 m3/hr = 56.25 m3/hr
Taking 20% as hydraulic overloading, then
Total flow to the sludge thickener = 166.25x 1.2 = 199.5 say 200 m3/hr
Sludge Thickener:
The total sludge flow to the thickener will be 24448.1Kg/day considering PTP sludge.
Sludge Thickener Underflow = (24448.1) / 5%
= 488962 kg/d
Centrifuge Outlet Solid load (5%) = 488962 x 0.05 = 24448.1 kg/d
Hence total solid load to thickener = 24448.1 + 24448.1
= 48896.2 kg/d (Sludge from PTP Clarifier + Sludge from Centrifuge)
Hence, one (1) number Sludge thickener will be provided to increase the sludge
concentration from 2% to 5%.
Considering solid loading rate as 100 kg/m2/d, flow area of Sludge Thickener
= (48896.2) / 100
= 488.96 m2
Considering hydraulic loading rate as 6 m3/m2/d, flow area of Sludge Thickener
= (200) / 6
= 33.33 m2
So, the required flow area is 488.96 m2
Hence the Inside Diameter of the Sludge Thickener will be 24.95 m say 25 m.
The water depth (WD) of the Sludge Thickener will be 4.0m. With this the detention time
of the Sludge Thickener will be,
= {[π x (25.02-1.22)/4] x 4.0}/200
= 9.79 hours
B
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 23 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
Hence, Sludge Thickener with dimensions - 25.0 (ID) x 4.0m (SWD) will be provided.
Thickened Sludge Transfer Pumps:
Considering outlet concentration of Sludge Thickener as 5%,
Sludge Thickener Underflow = (48896.2) / 5%
= 977924 kg/d
= 889.02 m3/d (SG = 1.1)
= 37.04 m3/hr
One number of 300m3 (as per tender requirement) capacity, thickened sludge sump will
be provided.
Four (4) no’s (3W + 1S) screw type Centrifuge Feed Pumps of 25 m3/hr will be provided
to feed the Centrifuges from Sludge Thickener.
Hence, four (4) no’s (3W+1S) Centrifuges of 25 m3/hr will be provided.
Sludge Thickener:
Sr.No Description Unit Specification
1 Flow Rate of influent m3/hr 200
2 Size m 25.0 Diameter X 4.0 SWD
3 Quantity Nos 1
4 MOC - RCC (Construction
By Client)
Thickened Sludge Collection Pit:
Sr.No Description Unit Specification
1 Capacity m3 300
2 Size m Later
3 Quantity No 1
4 MOC - RCC (By Client)
B
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 24 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
Poly dosing system:
Sr. No Description Unit Specification
1 Type of pump -
Diaphragm Type
hydraulically operated
metering pump
2 Duty - Intermittent
3 Flow Rate m3 75 (Design)
4 Chemical Poly solution
5 Design Dosing Rate (100 %) ppm 2 (Design)
6 Solution Concentration % 1
7 Specific gravity (100 %) 1.1
8 Chemical Dosing
requirement/compartment lts 164
10 Dosing Tank Capacity (10 %
margin) lts 180
11 Type of tank Vertical rectangular
with flat bottom
12 Dosing Tank Quantity - 2 Nos
13 Dosing Tank MOC CSRL
14 Dosing Pump Capacity Provided lph 15
15 Number of Pumps - 2 (1W + 1S)
16 Pump Total Head mwc 20 mwc
17 MOC
Wetted parts SS 316
Diaphragm PTFE
18 Dosing Tank Agitator Quantity - 1 / SS with epoxy
painting
B
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 25 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
Thickened Supernatant Collection System:
Sr. No Description Unit Specification
1 Tank Capacity m3 160
2 Type of tank Underground
3 Tank Quantity - 1 No
4 Tank MOC RCC
5 Pump Capacity Provided m3/hr 50
6 Number of Pumps - 3 (2W + 1S)
7 Pump Total Head mwc 25 mwc
8 Type of pump - Vertical Centrifugal
9 Duty - Intermittent
10 MOC
Casing 2.5 % Ni CI as per IS
210 FG 260
Impeller SS 316
Shaft SS 410
Centrifuge :
Sr. No Description Unit Specification
1 Qty Nos 4 (3W+1S)
2 Capacity m3/hr 25
3 Tank MOC SS 316
4 Feed Pump Capacity Provided m3/hr 25
5 Number of Pumps - 4 (3W + 1S)
6 Pump Total Head mwc 25 mwc
7 Type of pump - Screw Pump
8 Duty - Intermittent
9 MOC-Casing 2% Ni CI to IS 210 FG
260
Rotor / gear SS 316
Stator Nitrile / EPDM
Shaft and shaft sleeve
ASTM A 276 Gr 410 & SS
316
B
B
BGR ENERGY SYSTEMS LTD
ENVIRONMENTAL ENGINEERING DIVISION
Sheet 26 of 26
DOCUMENT NO: GID-1675-ME-ETP-BS-1018
DBR FOR EFFLUENT TREATMENT PLANT
Rev B
15.0 Treated Water Quality
The treated water quality in general will meet the quality as mentioned below. This
is subject to Water analysis provided by you.
Treated Effluent Characteristics:
At Sludge Thickener:
Total Suspended Solids- 50 mg/l
At CPI Outlet:
Oil- 10 mg/l
Total Suspended Solids < 100 mg/l
At Coal Particle Settling Basin Outlet:
Total Suspended Solids < 100 mg/l
Note:
The treated Water Quality is subjected to the following conditions
The Feed Water Quality being equal or better than Quality indicated in the
offer.
Any change in the technical parameter may have a technical and
commercial implication