SuratMunicipal Corporation

WASTE WATER RECOVERY&ENERGY GENERATION THROUGH SEWAGE GAS BASED POWER PLANT

Mr. Bhairav Desai Assistant Engineer – Drainage Department Surat Municipal Corporation

Location of Surat

Surat

• Surat dates back to 300 BC

• Municipality Established in 1852

• Municipal Corporation Formed in 1966

About Surat City

8th Largest in India as per population

4th fastest growing city globally

Termed as Economic Capital of Gujarat

9/10 Diamonds in the world are cut and polished here

40% of nations total man-made fabric & 28% of nation’s total man-made fiber production

Growth of City

Year Area in Sq. Km Population

1951 8.18 2,23,182

1961 8.18 2,88,026

1971 33.85 4,71,656

1981 55.56 7,76,583

1991 111.16 14,98,817

2001 112.27 24,33,785

2001* 326.51 28,77,241

2011 326.51 44,61,026

• Unprecedented growth in last four decades• Decadal Growth ~ 60-80%• 10-fold population rise• 10-fold area rise• City area expanded from

33.85 sqkm in 1971 to 326 sqkm in 2006

05/02/23

Sewerage System

05/02/23

Sewerage Scenario

Coverage : 167.50 sq.km. (i.e. 82 % of present

habitable area of @ 204 sq.km.)

Population catered : 97 % of present population

Length of sewer network : >1776 km

Nos of sewer manholes : > 65,000

Sewage Pumping Stations : 60 Nos (1986 MLD)

Sewage Treatment Plants : 11 Nos (982.5 MLD)

05/02/23

Treatment Technologies Adopted

Sr.No.

Location of Treatment plant

Year of Commissioning

Capacity (MLD)

Process

1 Anjana 1995+2007 82.5 Conventional Activated Sludge

2 Bhesan 1995+2008 100 Conventional Activated Sludge

3 Bhatar 1999+2014 162 Conventional Activated Sludge+ SBR technology

4 Karanj 1999+2015 140 Conventional Activated Sludge+ Fixed film Technology

5 Singanpore 2003+2014 155 Conventional Activated Sludge + SBR technology

6 Bamroli 2002 100 UASB+ Extended Aeration

7 Asarma 2009 15 Moving Bed Bio Reactor

8 Khajod 2009 25 Moving Bed Bio Reactor

9 Variav-Kosad 2012 84 UASB+ Moving Bed Bio Reactor

10 Dindoli 2013 66 Conventional Activated Sludge

Grand Total 929.5

Sr.No.

Location of Treatment plant

Year of commissioning

Capacity (MLD)

Process

1 Anjana 1995 82.5 Conventional Activated Sludge

2 Bhesan 1995+2008 100 Conventional Activated Sludge

3 Bhatar 1999+2014 162 Conventional Activated Sludge+ SBR technology

4 Karanj 1999+2014 140 Conventional Activated Sludge+ Fixed film Technology

5 Singanpore 2003+2014 155 Conventional Activated Sludge + SBR technology

6 Bamroli 2002 100 UASB+ Extended Aeration

7 Asarma 2011 15 Moving Bed Bio Reactor

8 Khajod 2011 25 Moving Bed Bio Reactor

9 Variav-Kosad 2012 84 UASB+ Moving Bed Bio Reactor

10 Dindoli 2013 66 Conventional Activated Sludge

11 Gavier 2016 53 SBR Technology12 Grand Total 982.5

Sewage Treatment Plant

• Latest technology for Sewage treatment• MBBR (Moving Bed Bio Reactor) for STPs at Asharma & Khajod• UASB+MBBR (Up-flow Anaerobic Sludge Blanket + Moving Bed Bio

Reactor) treatment technology for Variav-Kosad STP• SBR (Sequential Batch Reactor) for STPs at Gavier, Siganpore and Bhatar• Fixed Film technology for Karanj STP• Use of Mechanical Dewatering System for Sludge Drying• Belt Filter Press• Centrifuge

Tertiary Sewage Treatment Plant

05/02/23

Bamroli Sewage Treatment Plant

Single Stage Biological Treatment (2003)Two Stage Biological / Secondary Treatment (2008)Tertiary Treatment (2014)

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Bamroli Sewage Treatment Plant

Phase : I – Single Stage Biological Treatment

Capacity : 100 MLD Technology : Anaerobic Biological Treatment through UASB system. Year of Commissioning : 2003

Phase : II – Two Stage Biological / Secondary Treatment Capacity : 100 MLD Technology : Plant upgraded through Extended Aeration to meet the

revised stringent effluent discharge standards. Year of Commissioning : 2008

Phase : III - Tertiary Treatment Capacity : 40 MLD Product Water Technology : Ultra Filtration (UF) & Reverse Osmosis (RO) System. Year of Commissioning : 2014

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• Potable water demand is anticipated 2100 MLD by year 2025 as per master plan for projected Population.

• To meet huge water requirement due to industrial development, recycle and reuse of water is essential.

• Assured water requirement and assured revenue generation; enable guaranteed recovery of O&M cost by implementing such project on EPC basis.

• Revenue generation from recycled Waste water.

• Assured Water supply for Pandesara Industrial units.

Need of Waste Water Recycling Project

05/02/23

Recycle, Reuse of Sewage Water Through Tertiary Treatment : Bamroli STP

05/02/23

• Tertiary treatment of secondary treated sewage and to generate Industrial Grade Water for supply of Industrial Grade water to Pandesara Industrial Estate.

Tertiary Sewage Treatment Plant - Waste water Recycle - Reuse Project

PROJECT CONCEPT

OBJECTIVE Recycle / Reuse of waste water Contribution towards reducing the dependency on conventional

resources of water.

TECHNOLOGY

Sand Filtration Ultra-filtration (UF) Reverse Osmosis (RO) Activated Carbon Filter (ACF)

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Tertiary Sewage Treatment PlantCapacity of the plant : 40 MLD Contractor : M/s Enviro Control Associates (I) Pvt. LtdTechnology partner : M/s Hyflux, SingaporeCapital Project Cost : Rs. 85.10 croresPresent Fresh water cost to Industries : Rs. 23/KLRecycle water cost to Industries : Rs. 18.20/KL

(Yearly Increment on Indexation base)Project started -Commissined : August – 2012 / May - 2014Total ind. grade water supplied : 26,775 MLD (Till Oct-2016)Gross Income : Rs.50.92 Crore (Till Oct-2016)

Tertiary Treatment ProcessSecondary

Effluent

Ultra filtration

Reverse Osmosis

Pre- Chlorination

Post-Chlorination& pH adjustment

Flocculation

Product water Tank

To Pandesara Industrial

Estate

Activated Carbon Filter

Sand Filter

Disposal

Reject Water

57 MLD

8 MLD

Degasser System

Chemical Dosing

32 MLD

32 MLD

61 MLD

43 MLD

21 MLD

8 MLD

Partners & RolesSMC

• Conceptualization of project

• Preparation of detailed design, invitation of tender and selection of operating agency

• Project funding• Land allocation• Project execution• Payment of electricity

bill

GIDC - Pandesara

• End consumer• Assurance to purchase

committed quantity for well defined time duration

• Acceptance of the rate structure as mutually agreed

• Agreed to price variation corresponding to RBI index

• Regular payment to support the system

Contractor• Monitoring of inlet and

outlet parameters • Construction of plant to

meet the desired parameters

• Complete O&M of the plant including all major/minor repairs, replacements including spares

• Comprehensive treatment responsibility from collection point to disposal point

Parameters Inlet of TTP Outlet of TTPDesirable limits as per

Drinking water standard IS-10500

Color (Hazen units) 55 <5 5

pH 6.5-7.5 6-7.5 6-8.5

Total Hardness as CaCO3 (mg/L

750 <300 300

Iron as Fe(mg/L) 0.63 <0.25 0.30

Manganese as Mn (mg/L)

0.12 <0.10 0.10

Total Dissolved Solids (mg/L)

2100 <500 500

BOD (mg/L) 20 <5 No Standard

COD (mg/L) 100 <50 No Standard

Suspended Solids (mg/L) 30 <2 5.0 (Turbidity)

Total Nitrogen as N (mg/L)

14 <10 10.20

Total Phosphorous as P (mg/L)

8 6-10 -

Residual Chlorine (mg/L) 0.5 0.5 <0.25

Treated Water Quality Achieved TTP Inlet

TTP Outlet

Raw-TTP Inlet-TTP Outlet

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• Reject-water from Sand Filter, UF & RO is subjected to chemical treatment for reduction of Suspended Solids and BOD.

• The reject flow is pumped to the flash mixer and then to the flocculator.

• After flocculation, the reject flow is taken to the clarifier units. • The overflow from the clarifiers are connected to the existing

treated water disposal line of STP at the nearest point. Similarly the sludge is taken to Belt Filter Press system.

Major Treatment Units : Reject-Water Treatment

05/02/23

• SMC was supplying 50-55 MLD potable water to Pandesara industries

• After introduction of tertiary water; supply is increased to 80-85 MLD.

• New network with separate water lines are installed for potable water and tertiary water in Pandesara industrial area.

• Tertiary water and potable water lines are separately color coded.

• Tertiary water is currently blended with fresh water up to 50% .

Tertiary Water Distribution Mechanism

05/02/23

Project Financing & Payback# Financial Components Value

1 Capital Project Cost (including rehabilitation of water network)

Rs. 88 crores

2 O & M Cost (including electricity and 5% yrly. rise) for 18 years

Rs. 402 crore

3 Total inflow including Capex and Opex for 18 years 490 crore

4 Rate of Industrial Grade Water Rs. 18.20 per KL

5 Average rate of industrial water for 18 years Rs. 28.44 per KL

7 Total income for 18 years Rs. 747 crore

8 Payback Period 7 to 8 years

05/02/23

• Reduced diversion of drinking water for non-potable purposes.• Conserve valuable ground water resources for future generation.• Facilitates recycling of wastewater - an environmentally sound and

progressive advance practice.• Assured resource for Pandesara Industrial Estate.• Enabled SMC to reduce pressure on conventional water resources in the

city.• Guaranteed revenue generation for Surat Municipal Corporation.

Tertiary Sewage Treatment Plant - Waste water Recycle - Reuse Project

BENIFITS

05/02/23

• Seasonal variation in water requirement from industries.• Interrupted power supply for entire sewerage system and tertiary

system.• Mixing of Industrial Waste in to domestic sewage resulting to

disturbance of the plant performance.• Fluctuation in sewage quality, resulting in higher maintenance of

RO/UF ; consequently impact on life of RO.• Higher Sensitivity and complexity of system impact on tertiary

plant output.• Dependency on technology provider for trouble shooting.• Advance monitoring system for continuous monitoring of

incoming flow for non scheduled parameters is required. (i.e. Nano particles from textile industry)

Challenges

05/02/23

• Interrupted power supply for entire sewerage system and Construction of Clarifloculator to control the inlet water quality to UF-RO system.

• Introduction of control techniques such as VFD and Equalization tank.

• Increase Tertiary treated water storage capacity in Plant.• Installation of express power feeder for uninterrupted power

supply.• Close and Continuous monitoring of Raw sewage / process

parameters.• Capacity Building of Staff.

Action Taken to meet the Challenges

05/02/23

• Recycle & Reuse of Waste Water

• Augment Bamroli TTP from 40 MLD to 80 MLD.

• Tertiary treatment plant at Bhesan, Variav and Asharma for recycling of water for Hazira based industries, that may reduce water demand from Siganpore reservoir.

• Tertiary treatment plant at Dindoli and Bhatar for Sachin GIDC.

Replicability

05/02/23

Future Plan – Towards zero discharge (2025)

Year Projected Sewage Collection (in MLD)

TTP Capacity(in MLD)

2016 860 402017 930 802018 1005 1532019 1080 2092020 1155 3592021 1210 4502022 1275 5602023 1345 7102024 1410 7702025 1470 825

SuratMunicipal Corporation

Sewage Gas Based Power Generation

Plant

• As an initiative towards Green Energy Generation from Sewerage; Sewage Gas Based Power Plant at STPs has been setup.

• Operational Biogas based power plant (6 Nos. - 4.625 MW)• Anjana : 0.5 MWe• Bhatar : 1.0 MWe• Karanj : 1.0 MWe• Singanpore : 1.0 MWe• Variav : 0.625 MWe• Bamroli : 0.5 MWe

• Till October- 2016, total Power generation from Bio gas based power plant is 5.35 crore KWH turned in to saving of Aapproximately Rs.25.78 Crore

Sustainable Initiative

05/02/23

SYSTEM LAYOUT

• The Production of electricity through purely on sewage gas based engine generator technology have much more advantages and cost benefits over the earlier technology of duel fuel engine generator set.

• Power generation and utilization of it in sewage treatment plant reduce the electricity consumption of grid power.

• Saving in electricity bill will reduce revenue expenditure of Sewage treatment plant of SMC.

• Reduction of emission of green house gases for the protection of environment.

TECHNOLOGICAL REFORMS & BENEFITS

SURATMUNICIPAL

CORPORATION

Thank you