International Workshop PPP Models and Technological Solutions for Sewage and Waste Management September 22-23, 2011 *Welcome* Organized by &
September 22-23, 2011 International Workshop PPP Models and Technological Solutions for Sewage and Waste Management • The Vision of Ganga River Basin • Sewage and Waste Management Plan by SWaRA WWF-India NEERI CFRI JNU … … … PU BESU IT BHU DU ISI Kolkata
MoA between IITs (MHRD) & MoEFforPreparing Ganga River Basin Environment Management Plan(GRB EMP)
Our Mandate Prepare GRBEMP which will restore Wholesomeness of the River Ganga
Belief The qualities of the Ganga water are: Coolness, sweetness, transparency, high tonic property, wholesomeness, potability, ability to remove evils, ability to resuscitate from swoon caused by dehydration, digestive property and ability to retain wisdom
Challenge Protecting the river system • Un-polluted Flow ( ) • Longitudinal, lateral and vertical connectivity • Adequate space for various river functions • Ecological entity • Continuously flow ( ) Adequate provision of soil, water and energy Growing population, urbanization, industrialization and agriculture
Our Philosophy Can not afford to Experiment with River Like Ganga! Precautionary Principles must apply wherever knowledge gaps and uncertainties exist Apply modern science and new technologies but with traditional wisdom GyanDhara + Jana Gyan Supportive Capacityand Assimilative Capacity
Our Strategy Working: Parts to Whole Thought Process: Whole to Parts
Our Approach FGM WRM Water Resource Management ENB NATIONAL RIVER River with unique Ecosystem and Biodiversity Gangotri Environmental Quality and Pollution Ganga Sagar EQP SEC Socio-Cultural Heritage Geomorphological Changes: Erosion, Sediment Transport/Deposition And Floods PLG COM GDM
Sewage Treatment GRB EMP : • Report Indexing • Concept Map GEN Recommendations and Guidelines EQP 01 Literature (SOA) WRM GRB EMP * Main Document 02 FGM Methodology (MTH) ENB 03 SEC 04 Data (DAT) Areas Ver (MMM YYYY) PLG - GDM Analysis (ANL) - COM PIC - EFL Suggestions & Recommendations (S&R) MIS nn VISION 004 _GBP _IIT _EQP _S&R _02 _Ver 1 _Dec 2010 MISSIONS Nirmal Dhara Aviral Dhara Ecological Restoration Goals & Objectives Navigation & Recreation River Course Development Work Packages Water Resource Development Sustainable Agriculture Flood prevention Financial Layout Strategy Implementation Schedule Monitoring Mechanisms
NirmalDhara OR Un-polluted Flow Point Wastes Non Point Solid (non-point) Liquid Domestic Agriculture (non-point) Industrial Old Cities Villages New Sewage Collection Treatment Small Drains Open Defecation
The Mantra: Thirteen actions are prohibited on approaching the scared waters of the Ganga, namely: • Defecation • Ablutions • Discharge of wastewater • Throwing of used floral offerings • Rubbing of filth • Body shampooing • Frolicking • Acceptance of donations • Obscenity • Offering of inappropriate praises or even hymns in a incorrect way • Discarding of garments • Beating and • Swimming across, in particular
NirmalDhara OR Un-polluted Flow Zero Discharge Unpolluted Flow Cynical Attitude Unsatisfactory Performance STP Less than 1 Paisa Per Liter or Rs 10 Per Cum Expensive/Unaffordable/Energy Extensive ULBs !
Why ZLD and Reuse/Recycle? Monthly Flow in Indian Rivers
Why ZLD and Reuse/Recycle? Monthly Flow in Indian Rivers Flow (Cumecs)
Monthly Flow in Rivers Flowing Through Western Countries Why ZLD and Reuse/Recycle?
Monthly Flow in Rivers Flowing Through Western Countries Why ZLD and Reuse/Recycle? Flow (Cumecs)
Why ZLD and Reuse/Recycle? Monthly Rainfall & Number of Rainy Days in Ganga Basin
Why ZLD and Reuse/Recycle? • River Water Quality – Fecal Contamination! • Disinfection of Secondary Treated Sewage/Wastewater! • Experience with monitoring/regulating effluent discharges! • Getting value out of Sewage/Wastewater! • Energy/Manure • Water!
Sewage Treatment • Centralized Treatment V/S Decentralized Treatment • Concept not a Technology • Few Large STPs V/S Many Small STPs • Conveyance Cost of Sewage and now of Treated Water
Sewage Treatment – Guidelines and Recommendations • Sewage is a major point source of pollution. • The target of “NirmalDhara” i.e. unpolluted flow can be achieved if discharge of pollutants in the river channel is completely stopped. • Also, sewage can be viewed as a source of water that can be used for various beneficial uses including ground water recharge through surface storage of treated water and/or rain/flood water in an unlined reservoir. • This may also help achieving “AviralDhara”.
Sewage Treatment – Guidelines and Recommendations • In order to reduce substantial expenditure on long distance conveyance of sewage as well as treated water for recycling, decentralized treatment of sewage is advisable. • As a rule, sewage treatment plant (STP) of greater than 50 MLD should be avoided. • All new developments must build in water recycling and zero liquid discharge systems. Fresh water intake should be restricted only to direct human-contact beneficial uses of water. • For all other uses properly treated sewage/wastewater should be used wherever sufficient quantity of sewage is available as a source water for such purposes. • All new community sanitation systems must adopt recycling of treated water for flushing and completely isolate fecal matter until it is converted into safe and usable organic manure.
Stage I: Preliminary Treatment: • Three Stage Screening: • 25 mm bar racks (before pumping) • 12 mm bar racks • 5 mm mesh (< 2 mm mesh for MBR) • Aerated Grit Chamber if following unit operation is aerobic and Normal Grit Chamber if following unit operation is anaerobic. • Expected effluent quality after preliminary treatment: • No floating materials including polythene bags, small pouches, etc. • Proper collection and disposal of screening and grit.
Stage II Primary and/or Secondary Treatment • Many options are available for second stage treatment. These options can be grouped into following three categories. • Pond Based Systems or • Activated Sludge Process (ASP) and its Modifications or equivalent systems including but not limited to SBR, UASB followed by ASP, ASP operated on Extended Aeration mode (EA-ASP), ASP with Biological Nutrient Removal (ASP+BNR), and MBBR or • MBR • Expected effluent quality after primary and secondary treatment: • BOD < 30 mg/L • SS < 20 mg/L • Nitrified effluent
Stage III: Tertiary Treatment - Options and Norms • Coagulation-flocculation-settling followed by filtration and disinfection is generally recommended. • Other processes could be selected on the basis of land availability, cost considerations, O&M cost, reuse option, compatibility issues in case of up-gradation of existing plants, etc. However, disinfection operation should invariably be included. • Where sewage flows are low and/or land can be spared without compromising on other developmental objectives or agriculture, waste stabilization ponds followed by constructed wetland can be adopted without coagulation-flocculation-settling. • Expected effluent quality after tertiary treatment: • BOD < 10 mg/L • SS < 5 mg/L • Phosphate < 0.5 mg/L • MPN of fecal coliforms < 10/ 100 mL
Treatment Cost (as in 2010) and Corresponding Plant Footprint for various Secondary Treatment Options Treatment Cost, `/kL Treatment Plant Footprint, m2/MLD
Comparison of Treatment Costs of Various Technologies for Sewage Treatment in India
Sewage Treatment – Guidelines and Recommendations • Sludge Management • The sludge dewatering should be done using thickener followed by filter press or centrifuge or any other equivalent mechanical device. • Sludge drying beds (SDB) should be provided for emergency only. SDBs should be designed only for 15% of the sludge generated from primary and secondary processes. • The compressed sludge should be converted into good quality manure using composting and/or vermi-composting processes. • Energy generation through anaerobic digestion of sludges in the form of biogas and subsequent conversion to electrical energy as of now is viable only when sewage BOD > 250 mg/L. • Single fuel engines should be used for conversion of biogas to electrical energy. • Hazardous sludge, if any should be disposed of as per the prevailing regulations.
Sewage Treatment – Guidelines and Recommendations • Bioassay Test • Flow rate (retention time) • Total flow requirement: 10% of the flow (subjected to maximum 1 MLD) is required to pass through the bioassay pond. • Depth of flow-through system or pond • Test organisms • Aeration and oxygen requirements • Requirement of Dechlorination • Bioassay test acceptability criterion: No mortality (100% survival) of test organisms under any condition.
Sewage Treatment – Guidelines and Recommendations • Flow Measurement • Flow measuring devices should be installed after the Stage I Treatment as well as at the outlet of the sewage treatment plant. • These flow devices should be of properly calibrated V notch with arrangements for automatic measurement of head. • Additional electronic or other type of flow meters may also be installed. • Arrangements should be made for real time display of measured (both current and monthly cumulative) flows at prominent places.
Salient Features of Recommended STPs (Report 003_GBP_IIT_EQP_S&R_02_Ver 1_Dec 2010) Summarizing – Salient Features • Continuous measurement of flow at the inlet and outlet • Excellent preliminary treatment • Treatment up to tertiary level • Online bioassay test • Designed and built as modular units • Pumping and STPs to be taken together for contracting/bidding
Highlights • Generation of about 10,000 MLD of Sewage from about 200 Class I Towns in Ganga River Basin (15 MLD to 1000 MLD) • Sewage / wastewater in all Class I cities in the GRB to be treated to tertiary level and reused. Discharging in River is unacceptable. • The ULBs are both unwilling and unable to pay for this due to various reasons. This situation is un likely to change in near future. • A Techno-financial solution must be such that objective at 1 above is realized notwithstanding the limitations as stated in point 2 above. • Who will pay for this? • Our vision is to utilize the limited resources available with the Central Government (through World Bank Loan!)/ State Governments to develop market for reuse/recycle of treated sewage/wastewater and even generate resources from sewage to ULBs
Issues to Discuss and Resolve • Prospects of generating resources through sale of treated water, energy from waste, and sludge or sludge derived products. • Changes and/or introduction of new policies/legislations/regulations/governance mechanisms at the central, state and local government level to facilitate establishing market for or generating resources from sale of treated water, energy and sludge or sludge derived products. • Performance assurance to be obtained from private party and required payment guarantee for successful implementation of the proposed or any other DBFO or equivalent models. • Prospects of finding private entities interested in technology transfer and investments in recycle and reuse of sewage and industrial effluents.
Issues to Discuss and Resolve • Framework for concession agreements or contract documents amongst urban local bodies (ULBs), state governments, central government and private entities for sewage treatment and reuse/recycle. • Framework for concession agreements or contract documents amongst industries, industry associations, state and central government and private entities for treatment and reuse/recycle of industrial effluents. • Road map for working on technology transfer and developing PPP models for management of both sewage and industrial effluents. • Road map for building on model projects through bilateral and/or other funding agreements for achieving the target of Clean Ganga Mission of the Government of India by 2020. • ………………………………………………