GIZ Support to Ministry of Urban Development Training on Preparation of City Sanitation Plan Part III State of Telangana

Transcription

1 GIZ Support to Ministry of Urban Development Training on Preparation of City Sanitation Plan Part III State of Telangana Session 3B: Technical Options for CSPs Hyderabad, April 2016 Slide 1

2 Technological options for On-site Sanitation systems Septic Tank with Soak pit Twin-Pit Latrine Bio-Digester DRDO Bio Tank / Bio Toilets Slide 2

3 Septic Tank followed by Soak pit Slide 3

4 Septic Tank followed by Soak pit Septic Tanks are applicable to all types of Toilets (Individual, Community, Public Toilets) All septic tanks should be constructed as per standards (Retrofitting of non-standard septic tanks) Septic Tanks are generally designed only for Black water Septic Tank removes about 50 to 60% of the biological load in wastewater Effluent from Septic Tanks further needs Secondary Treatment Septic Tanks must be emptied every 2 to 3 years Limitation: Cost and space requirement Slide 4

5 Septic Tank followed by Soak pit Slide 5

6 Septic Tank followed by Soak pit Soak Pit : The soak pit may be of any suitable shape with the least cross-sectional dimension of 0.90 m and not less than 1 m in depth below the invert level of the inlet pipe Cost Estimates (for 5 users) : Tentative cost varies from Rs. 25,000 to Rs. 30,000 depending upon the construction material (including toilet) Pre fabricated septic tanks are available at lower cost in the market, which also may be explored to speed up the implementation. Slide 6

7 Twin-Pit Latrines Slide 7

8 Twin-Pit Latrines Twin-Pit Latrines are only applicable to Individual Toilets Each pit should be designed to hold at-least one year accumulation of fecal sludge The pits must be used alternatively & the diversion chamber must be accessible The digested fecal sludge should be safely emptied, transported & treated / disposed Limitation: Households may not use the pits alternately, Water may percolate through the soil & pollute groundwater Slide 8

9 Twin-Pit Latrines Size of pits: Cost Estimates (for 5 users) : Tentative cost varies from Rs. 15,000 to Rs. 20,000 depending upon the construction material Twin-pit latrines in special conditions: - In water-logged areas - In high subsoil water level - Where space is a constraint Slide 9

10 DRDO Bio-Digester Toilet Slide 10

11 DRDO Bio-Digester Toilet Bio-Digester Toilet is an anaerobic multi-compartment tank with anaerobic bacteria which digests organic material biologically It converts fecal waste into usable water & gases in an ecofriendly manner No sludge formation, hence no desludging & treatment Semi treated water from bio-digester tank is needed to be further disposed into a soak pit for further treatment Less space requirement Slide 11

12 DRDO Bio-Digester Toilet Cost Estimates : Slide 12

13 Bio Tanks / Bio Toilets Slide 13

14 Bio Tanks / Bio Toilets Bio-Toilets is an multi-compartment tank with aerobic bacteria which breaks down the waste matter through oxidation. Effluent from the Bio Tank can be directly discharged since it is completely safe Limitation : O & M needs proper attention, Need proper bacteria inoculation periodically, chlorine dose is necessary for disinfection, Acid / detergent should not be used to clean the pan Cost Estimates : Tentative cost is approx. Rs. 20,000 depending upon material of construction (including toilet) Slide 14

15 Choosing appropriate On-site sanitation system No. Parameters Septic Tank Twin-Pit Latrine DRDO Bio-Digester Bio Tanks 1 Toilet Suitability Suitable for all types of toilets Suitable only for Individual HH toilets 2 Treatment efficiency Partial treatment Partial treatment (50-60 %) Suitable for all types of toilets Partial treatment (80 %) Suitable for all types of toilets Full treatment (100 %) 3 Desludging Required periodically Required periodically No need for desludging 4 Soil type For soak pits to function, soil condition must be suitable 5 Ground water table Suitable in lower GWT areas 6 Effluent Effluent should be passed through soak pit before discharge For twin pits to function, soil condition must be suitable Suitable in lower GWT areas Waste-water percolates through the pit to the subsoil For soak pits to function, soil condition must be suitable Suitable in lower GWT areas Effluent should be passed through soak pit before discharge No need for desludging No effect of soil type No effect of GWT Effluent is completely safe & can be directly discharged 7 O & M Reasonable attention Reasonable attention Minimum attention Maximum attention 8 Land requirement sq. ft sq. ft 25 sq. ft 16 sq. ft 9 Approx. Cost (including toilet) Rs. 25,000-30,000 Rs.15,000-20,000 Rs. 24,000-37,000 Rs. 20,000 Slide 15

16 Waste Management Hierarchy At source reduction & reuse the most effective way to reduce the quantity of waste Slide 16

17 Waste Minimization Initiatives Promoting at source reduction program Green procurement & Take Back Program Bans within local authorities Promoting material exchange and reuse programs Extended Producer Responsibility Promotion of Voluntary action To frame rules and bye laws Slide 17

18 Source Segregation Segregation of waste at source in 3 categories: Wet Waste (kitchen waste) Dry Waste (recyclables) Domestic hazardous waste Slide 18

19 Storage of Municipal Solid Waste at Source Household level Storage Capacity lts 5 60 lts lts lts 48 Onsite Storage of bulk wastes Households Storage of MSW in public spaces/ parks- placement of bins at optimum distance m to avoid littering Number and capacity of bins required depends on the quantity of waste to be stored before collection & an additional 100% storage to avoid spillage Slide 20

20 Collection and Transportation Collection of segregated municipal waste from the source of its generation is an essential step in solid waste management. Collection service divided into primary and secondary collection. A well synchronised primary and secondary collection & transportation system leads to successful waste management Primary collection of segregated waste from households is carried out through the use of containerized push carts/ tricycle, small mechanized vehicle, compactors depending on the terrain, width of streets To improve/optimize collection efficiency, collection vehicles should be adapted to the street width, accessibility and localized conditions Slide 21

21 Vehicles and Equipment for Primary Collection Hand carts/ tricycles with containers/ bins Tricycle with hydraulic tipping containers Slide 22

22 Secondary Collection and Transportation Concept of Binless area/city Direct transfer of waste from the primary collection point to secondary collection vehicles promotes a binless arrangement. Successful only when synchronization with primary collection and coordination exist. For eg: Kochi, Nashik Municipal Corporation have implemented a bin-less system. Slide 24

23 Transfer Stations Transfer stations should be set up in large cities (>300tonnes of waste/day)where disposal sites are more than 15 km to save transportation time, equipment and fuel Usually consists of large size containers cu.mt Stationary Compactor Transfer Station Direct Transfer Station Slide 26

24 Technical Options- Processing & Treatment of Municipal Solid Waste Recycling & Recovery Composting Waste to Energy Refuse Derived Fuel Slide 27

25 Material Recovery Facilities Material Recovery Facility (MRF): Separating and diverting recyclable materials from mixture of waste fractions collected in the dry waste bin to MRF Configuration of a MRF: Quality, quantities of material to be processed processing rates desired quality of end products Extent of recycling depends on the size of the market for recycled products Necessary to assess and establish market linkages prior to bringing recycling programmes into operation Slide 28

26 Composting Controlled decomposition of the organic waste, typically in aerobic conditions Indian waste composition: amenable to composting Composting of segregated waste is preferred Mixed waste composting: ONLY with appropriate and effective presorting and treatment of feedstock Used as a valuable soil amendment thereby reducing dependence on chemical fertilizers Slide 29

27 Pre-processing of MSW MSW Feedstock for Composting: Segregated wet fraction of MSW, Vegetable market waste and Yard waste Pre processing of mixed MSW lowers processing cost, recovers recyclables, reduces contaminants Financial viability of compost plants primarily dependent on the marketability of the compost Successful market for compost primarily dependent on producing consistent quality and quantity of compost Co-marketing of compost with chemical fertilizers by the fertilizer companies as a Basket Approach is recommended Slide 30

28 Composting Technologies Windrow Composting Aerated Static Pile In-Vessel Composting Decentralized Composting Vermicomposting Slide 31

29 Windrow Composting 500 TPD Segregated waste: 18-20% efficiency Mixed waste: upto 10-15% efficiency Slide 32

30 Aerated Static Pile Segregated/pre-processed composting mixture placed in mechanically aerated piles Post-processing to remove bulking agents Key criteria for aerated static pile composting Effective for farm and municipal use tons/module Land required: 5 ha/500 tons (lower land required) Time: 6-12 weeks Temperature: not temperature sensitive Energy input: moderate (2-3 hours aeration required) Financial implications: relatively costly Slide 33

31 In-Vessel Composting Composting in single or multi-compartment vessels that provide mixing, aeration and moisture to waste feed Continuous feed/batch feed Key criteria for in-vessel composting Large- scale commercial systems tons/module Land required: 4 ha/500 tons Time: 3 weeks (3-5 days in vessel; 3 weeks to mature) Temperature: not temperature sensitive Energy input: high Financial implications: very costly Slide 34

32 Decentralized Composting Box composting/bin composting: Source separated organic waste from neighbourhood Preferred System: Reduces transportation costs, makes use of low-cost technologies based mainly on manual labour Small waste quantities upto 20 tons/day MSW Feedstock: Kitchen waste like food, fruit and vegetable leftovers (rich in nitrogen content), yard waste like leaves, twigs, straw and paper (rich in carbon content) Slide 35

33 Vermicomposting Composting the biodegradable fraction (kitchen/vegetable market waste) of MSW with the help of earthworms Results in the production of vermicompost soil conditioner Key criteria for vermicomposting Amount of waste treated: 1-50 tons/module Land required: 2 ha/50 tons Time: 8 weeks Temperature: Temperature sensitive (30-40 C ideal range) Energy input: low Financial implications: Purchase of exotic earthworms is expensive Slide 36

34 Waste to Energy Process of generating energy in the form of heat or electricity from MSW At least 65 to 80% of energy content of waste can be recovered as heat energy Waste to Energy technologies: Incineration Biomethanation Refuse Derived Fuels (RDF) Recovering energy value in waste prior to its final disposal is considered preferable Slide 37

35 Incineration Combustion of waste at very high temperatures, in the presence of oxygen Production of heat (flue gas, ash) The success of waste incineration projects depends entirely on incoming waste feed characteristics and quantity For financial viability of incineration plants: segregated waste feed of at least 500 TPD with a LCV not less than 1450 kcal/kg of waste Incineration of municipal solid waste (along with energy recovery) can reduce the volume of waste to be landfilled by 90% Slide 38

36 Biomethanation Anaerobic digestion of biodegradable organic waste in an enclosed space under controlled conditions, generating biogas comprising mainly of methane and carbon dioxide. Key criteria for successful biomethanation of MSW Consistent source of bio degradable organic matter free from inert material Sustainable demand for generated biogas in the vicinity of the plant at appropriate economic conditions. Market potential for the manure produced Decentralized systems: 1-5 TPD Slide 39

37 Refuse Derived Fuel High calorific non-recyclable fraction of processed MSW which can be used as a fuel for either steam/ electricity generation or as alternate fuel in industries RDF typically consists of high calorific fractions of MSW like paper, textile, jute etc. Utilization of RDF co-processing in cement kilns; co-combustion in coal fired power plants; on-site/off site in an appropriately designed waste incinerator for thermal recovery or power generation Slide 40

38 Co processing in Cement Kilns RDF can be used in cement plants as a substitute for fossil fuels. Long residence time, high temperature and turbulence in cement kilns ensures minimal production of dioxins and furans Desirable RDF Characteristics for Co-processing in Cement Kilns: Moisture: preferably < 25% Size, 2D < 70 mm, 3D < 35 mm (subject to process limitation) Chlorine, preferably < 0.7% (dependent on raw mix & fuel mix) Calorific Value, preferably > 2,800 kcal/kg Sulphur, < 2% (dependent on particular raw mix & fuel mix) Free of restricted items( PVC, Explosives, Batteries, Aerosol containers, Bio medical waste) Slide 41

39 Indicative Criteria for Selection of Appropriate Technology or Combination of Technologies CRITERIA WINDROW COMPOSTING VERMICULTURE BIOMETHANATION RDF INCINERATION INTEGRATED SYSTEM (COMPOSTING + RDF) SANITARY LANDFILL Land requirement For 300 TPD of segregated/presorted MSW: 5 ha of land including buffer zone is required For 20 TPD of segregated/presorted: 1.25 ha For 300 TPD of segregated/pre-sorted MSW: 2.5 ha of land is required For 300 TPD of segregated/pr e-sorted of MSW: 2 ha of land is required For 1000 TPD of mixed waste: 5 ha of land including buffer zone. For 300 TPD of segregated/presorted MSW: 6 ha of land (Note: Many of the processing units are shared) For 300 TPD of MSW: 30 ha of land is required for 20 years Waste quantity 20 TPD and above 1-20 TPD 1 TPD at small scale & 500 TPD at large scale 100 TPD of segregated waste 1000 TPD and above of mixed waste 500 TPD and above 100 TOD inert and obove Rejects About 30% including inerts if only composting is done. 15%* rejects with RDF, if located in the same plant About 15% including inerts* About 15% from mixed waste* Around 15% from mixed waste** Around 15%** Approximately 10%*** Slide 42 No rejects

40 Indicative Criteria for Selection of Appropriate Technology or Combination of Technologies CRITERIA WINDROW COMPOSTING VERMICULTURE BIOMETHANATION RDF INCINERATION INTEGRATED SYSTEM (COMPOSTING + RDF) SANITARY LANDFILL Capital Investment Cr for 500 TPD plant 1 Cr. per 20 TPD Cr for 500 TPD plant Cr for 500 TPD plant High capital O& M cost 15 cr per MW power production c r for 5000 TPD plant High Market for product Quality compost if compliant with FCO 2009 has high potential. Comarketing recommended with 304 bags of compost with 6-7 bags of chemical fertilizer good market potential in urban and rural areas however not adequately explored No appropriate system of pricing biogas. Pricing according to kerosene equivalent puts biogas at disadvantage High market potential for RDF. As a feeder in cement/ power plants High potential of energy generation if power purchase agreements are made High potential if complied with rules No potential since only inert waste are to be disposed in landfills Slide 43