Understanding FSM Part 2 Treatment Technologies Presented by

Understanding FSM Part 2 Treatment Technologies Presented by Amresh Sinha CDD Society Bangalore Date: December 23 rd & 24 th 2016 Place: Lucknow Under Sanitation Capacity Platform (SCBP)

Sanitation Capacity Building Platform What is it? Collaborative effort by NIUA for Mainstreaming Fecal Sludge Management at the state level and national sanitation agenda. Working with Expert Partner organsiations for FSM solutions, upscaling of capacity building and national level advoacy with the NFSSM group. We have sanitation challenges! ULB We can help you! WASHi 2

What is the current practise of FS Disposal? • Disposed in farm land • Disposed in river or water bodies • Disposed in Solid waste landfill sites? ?

Farm Lands • Heavy concentration of nutrients – affect plant growth • High risk of Faecal oral contamination for communities living near farmlands • Transmission through surface runoff or rodents • No single point source for disposal – Regulatory difficulties

Water bodies • High Risk hazard – Faecal oral contamination • Out break of diseases across population • Eutrophication of water bodies – Impact of flora and fauna and usage of water • Frothing of water bodies – unpleasant smell and visual

Treatment What can treatment do? • Reduce Smell and visually displeasing outputs • Stabilising the sludge to reduce health and environmental risks • Dedicated place for disposal – easy to regulate • Revenue generating end products

Factors Quality: Type of containment Quantity estimation Raw material Frequency Technology O&M requirement Skill End Product Active/Passive pathogen stabilization

Technology Options

Treatment – Objectives Selection of treatment options based on achievement of following objectives Priority Pathogen Removal Highest Organic Load Reduction Reuse Lowest

FS Characterization Characteristics of faecal sludges and comparison with tropical sewage (Heinss et al. , 1998) Item Example Characterization COD mg/l COD/BOD NH 4 -N mg/l TS mg/l SS mg/l Helm. eggs, no. /l Type "A" (High-Strength) Public toilet or bucket latrine sludge Highly concentrated, mostly fresh FS; stored for days or weeks only 20, 000 -50, 000 2: 1 - 5: 1 2, 000 - 5, 000 ≥ 3. 5% ≥ 30, 000 20, 000 - 60, 000 Type "B" (Low-Strength) Septage Sewage (For comparison's sake) Tropical sewage FS of low concentration; usually stored for several years; more stabilized than Type "A" <15, 000 5: 1 - 10: 1 <1, 000 < 3% ≈ 7, 000 ≈ 4, 000 500 -2, 500 2: 1 30 -70 < 1% 200 -700 300 -2, 000

Treatment – Approach 1 Separation of solids 2 Sludge stabilization 3 Dewatering / Drying 4 Sludge percolate treatment 5 Disinfection 6 Safe disposal / Reuse

Possible Treatment Options Source: Fecal sludge management systems approach for implementation and Operation, IWA Publications, 2014 12

Solid Liquid Separation and Dewatering Settling Tanks and Sedimentation Ponds Sludge Drying Beds Planted Sludge Drying Beds 13

Settling Tanks and Sedimentation Ponds • • Settling tanks provide a liquid retention time of a few hours (to ensure settling of Settleable solids) Sedimentation ponds provide a liquid retention of few days or several weeks designed on • Desired depth and • Quantity of accumulating solids The accumulating solids have to be removed and treated further 14

Sludge Drying Beds • It is a shallow filter tank filled with graded gravel mainly used for dewatering of stabilized sludge • Graded filter media of different diameter used for the depth of 50 -60 cm depth with the top layer as sand • Approximately 50 -80% of the liquid drains of as filtrate and 20 -50% due to evaporation • The depth of sludge applied per loading is not more than 30 cm • Sludge drying period range of 10 -20 days depending on the temperature 15

Planted Sludge Drying Beds FS is loaded with layers of sludge that are subsequently dewatered and stabilized through multiple physical and biological mechanisms • • • The beds consist of gravel/sand/soil filter planted with plants such as reeds, cattails, bulrushes Liquid fraction flows vertically downwards through media and is collected at bottom and treated separately Sludge retention time is 2 -3 years depending on sludge loading rate TS 16

Stabilization/Treatment Co-treatment with Wastewater Co – Composting with Municipal Solid waste Anaerobic Digestion: Biogas digester La. De. Pa pelletizer Mechanical Treatment Options 17

Co-treatment with Wastewater Septage addition at the nearest sewer manhole, upstream of STP Septage addition at STP Septage addition to Sludge Digesters / Sludge Drying Beds 18

Co – Composting with Municipal solid waste • Co-composting is a mixture of organic solid waste and faecal sludge with pre-defined moisture content (40 -60%) at specified condition • Human waste is rich with Nitrogen and moisture content; solid waste has high organic carbon content • Co – composting of Faecal Sludge and organic solid waste range from 1: 2 – 1: 10 depending on the Faecal Sludge characteristics and its water content 19

Anaerobic Digestion • • This process ensure effective sludge digestion and stabilization During digestion: 1. Organic matter is converted to biogas 2. The stabilized sludge (digestate) utilized as soil conditioner The SRT is maintained for 10 -15 days Removal of accumulated solids from the digester remain a challenge 20

Mechanical Treatment Options • • • The technologies used to treat wastewater sludges are also applicable for Faecal Sludge namely: 1. Belt Filter Press 2. Screw Press 3. Centrifuge Advantages of mechanical treatment options include compactness and speed of the process Limitations of mechanical treatment options include high investment costs, O&M and electricity requirements 21

Mechanical Treatment Options 22

La. De. Pa pelletizer Modifying a commercially available pyrolysis unit and adding dewatering and water treatment units. Pyrolysis is a process which decomposes matter using heat in the absence of oxygen. 23

La. De. Pa Pelletizer 24

Geo-tube bags • Geo bags are porous tubular containers fabricated with high strength woven geotextiles (polyethylene material) mainly used for dewatering sludge. • Bags will help to achieve the capture of 98% of solids from the sludge • Polymer will added to increase the solid settling • Filtrates from the container should be collected and treated properly before discharge 26

Intermediary solution Trenching Technique

Anaerobic based approach for Faecal sludge treatment Screen Chamber Settling Tank Sand grit removal Separation - free water id Liqu Faecal Sludge/Septage Effluent is discharged into agricultural fields, drain or water body 1. 2. 3. 4. 5. 6. Disposal Regular operator is required. O&M is simple Capital cost is high and recurrent cost is minimal Large area requirement (UG+OG) Suitable for large quantity (20 cum) Good treatment efficiency Regular feeding is not a issue Solids Liquid Treatment Liquid Anaerobic digester DEWATS Stabilization Liq uid Liquid-solid separation Solids End product is compost. Can be used as soil conditioner Disposal Co-composting Disinfection Enriching fertilizer value Unplanted drying bed Dewatering

Mineralization based approach for Faecal sludge treatment Screen Chamber Planted Drying beds Sand grit removal Stabilization Dewatering id Liqu Faecal Sludge/Septage Liquid Treatment Effluent is Disposal DEWATS discharged into agricultural fields, drain or water body 1. Commonly practiced technique due to simplicity 2. Moderate capital cost, Low recurring cost 3. Large area requirement 4. Good treatment efficiency 5. Location of the treatment system may be an issue – odor, flies 6. Operation and mainatainace may be an issue – acceptance 7. Regular feeding may be an issue Disinfection Solids Co-composting Disinfection Disposal End product is compost. Can be used as soil conditioner 29

Criteria: Selection of Technology • Quality and Quantity of FS • Land Availability / Location • O&M Availability • CAPEX / OPEX • End use requirement / Business model • Short term vs Long term • Climatic conditions 31

END USE

Key considerations • • • People’s needs and preferences (socio-cultural); Local materials, products and skills; Economic viability; Additional barriers; Regulatory aspects 33

End Use Methodologies END - USE Methodology DESCRIPTION Treated faecal sludge and urine can be applied to soil to improve plant growth by Soil Conditioner and Fertilizer a) increasing nutrients b) improving the physical structure of the soil. in Agriculture Biogas Faecal sludge is mixed with organic waste to produce biogas and digestate. Biogas is used as energy source for lighting and boiling Solid Fuel Dried faecal sludge can replace other fuels such as wood and charcoal, which are more expensive and damaging to the local environment Protein for animal feed Animals such as larvae feed on faecal sludge and provide a protein source for farm animals and fish Aquaculture Faecal sludge is fed to aquatic organisms such as fish and aquatic plants. These aquatic organisms can then be eaten directly used as animal feed or used as fertilizers

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