Energy recovery from Municipal solid waste. Dr. Pooja Ghosh DST Inspire Faculty CRDT, IIT-D

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1 Energy recovery from Municipal solid waste Dr. Pooja Ghosh DST Inspire Faculty CRDT, IIT-D

2 How we define waste? It is a material, substance, or by-product which is eliminated or discarded, as no longer useful or required after the completion of a process.

3 Waste is merely raw material in the wrong place - Frederick A Talbot in his book Millions from Waste 1920 It is not WASTE until it s WASTED

4 Municipal solid waste (MSW) The Municipal Solid Wastes (Management and Handling) Rules, 2000 has defined MSW as commercial and domestic wastes generated in municipal or notified areas in either solid or semi-solid form excluding industrial hazardous wastes but including treated bio-medical wastes. Organics (Kitchen waste, Agro waste, Garden waste) MSW Recyclables (Plastic, Paper, Tin cans, Metal, Glass, Syringes) Inert (Sand, Pebbles, Gravel)

5 MSW generation: A global overview Growing global population, rapid urbanization and economic development have led to increased MSW generation. In the year 2012, approximately 1.3 billion tons of MSW were generated globally. This amount has been predicted to rise to approximately 2.2 billion tons by the year The per capita generation of waste (kg/person/day) in case of developed countries is more (USA: 2 kg/person/day, Australia: 1.77 kg/person/day) compared to developing countries (India: 0.37 kg/person/day). However, the waste management options in developed countries have moved towards efficient waste management scenarios involving exploiting more energy and materials from waste stream and minimizing environmental pollution.

6 Waste Generation in India India is growing; and so are the mountains of waste its cities and villages are generating. CPCB Report, 2015: India produces approximately 52 million tonnes of waste each year (0.144 million tonnes per day).

7 Table 1 Major cities of India and per capita waste generation data ( ) Source: Census of India 2011, CPCB Report Delhi MSW generation (2016) 9,000 TPD Projected Delhi MSW generation (2021) Table 2 Waste generation per capita in Indian cities Source: Kumar et al., ,000-25,000 TPD The World Bank estimates that by 2025 solid waste generation in India will rise by 243 per cent.

8 Waste Composition in India

9 CPCB (2015)estimates 90 % Indian cities dispose their waste in landfills.

10 Leachate discharge Methane emissions

11 Landfills in India Non-Engineered No Baseliners No Leachate Collection System No CH4 capture Diagram of an Engineered landfill

12 Leachate Cause of Concern! Ø Dissolved organic matter Ø Inorganic macro components Ø Heavy metals Ø Xenobiotic organic compounds

13 Chemical and toxicological evaluation of leachate from municipal solid waste landfill sites of Delhi, India. #Contaminants #CancerRisk #Cytotoxicity #Genotoxicity Source: Ghosh P, Gupta A, Thakur IS (2015) Environmental Science and Pollution Research. 22:

14 Does urban MSW affect rural areas? Peri-urban or Intermediately Rural areas are the new targets for dumping solid wastes. For eg. Landfill sites at Mavallipura and Mandur villages near Bangalore.

15 September 11, 2014

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17 Proper WM is the need of the hour Ø Follow 4Rs: Reduce, Reuse, Recycle and Recover Ø Awareness to enhance Segregation Ø No more dumping in the Unengineered Landfills ØWaste to Energy Ø Policy measures: Charge for waste generation, producer responsibility scheme, landfill disposal bans So what is the solution for WM?

18 Concept of 4Rs needs to be followed seriously REDUCE: Reduce the amount of garbage generated. Alter your lifestyle so that minimum garbage is generated. REUSE: Reuse everything to its maximum after properly cleaning it. Make secondary use of different articles. RECYCLE: Keep things which can be recycled to be given to rag pickers or waste pickers. RECOVER: Recover energy by Anaerobic digestion, gasification, pyrolysis.

19 WASTE SEGREGATION Segregation of waste at source is important. It s an effort that pays everybody and solves half the city s problem of waste management. Waste segregation costs nothing and takes hardly any extra time. It s a matter of understanding and more about responsible behavior. When you segregate waste into two basic streams like organic (degradable) and inorganic (non-biodegradable), the waste generated is better understood and consequently recycled and reused with higher potential for recovery. Waste pickers typically use inorganic waste and segregate waste further into paper, metal, plastic and then sell them to earn a livelihood.

20 NO MORE DUMPING IN UNENGINEERED LANDFILL SITES Ghazipur landfill has already crossed 50 metres height and still 3000 tonnes per day waste is being dumped. The EDMC has not identified any other alternative site to dump waste so far. As per officials, the one site provided by DDA at O- Zone near Yamuna has been rejected by National Green Tribunal. The Ghazipur landfill was commissioned in 1984 and is not designed according to the Municipal Solid Waste Rules of 2000, which mandates all such dumpsites to have ecofriendly garbage management facilities.

21 NO MORE DUMPING IN UNENGINEERED LANDFILL SITES

22 MSW FOR RECOVERING ENERGY According to MNRE, energy recovery potential from MSW for the year 2017 for India was approximately 5200 MW. Of this, only 24 MW has been exploited, which is less than 1.5 % of the total potential. Maharashtra, UP, TN, WB Karnataka and AP with high urban population generate loads of MSW with significant power recovery potential over 100 MW each. Delhi due to its high population density has an energy potential equivalent to AP. 2012

23 MSW TO ENERGY TECHNOLOGIES

24 ANAEROBIC DIGESTION (Biochemical conversion) Consists of 4 stages involving different consortia of micro-organisms. Biogas (CH4 + CO2) is produced through digestion of organic materials in the absence of oxygen. It also contains sulfur compounds (H2S and alkythiols), ammonia, alcohols, carbonyl compounds (aldehydes and ketones), carboxylic acids in traces.

25 FACTORS AFFECTING BIOGAS PRODUCTION Temperature: Anaerobes are most active in the mesophilic (30-40 C) and thermophilic (50-60 C) temperature range. ph value: Desirable C/N Ratio: Desirable :1 Bacterial population Organic loading rate Hydraulic Retention time

26 METHANE PRODUCTION POTENTIAL OF DIFFERENT MSW Co-digestion Additives Pre-treatment Reference: Matsakas et al. (2017) Green conversion of municipal solid wastes into fuels and chemicals. Electronic Journal of Biotechnology 26,

27 INCINERATION (Thermal conversion) Involves complete combustion of solid waste at high temperature ( C) and aerated conditions. End products: Ash, flue gas and heat. The most attractive feature of incineration is that it helps in reducing the volume of combustible waste by %. Energy recovered can be used for electricity generation. Incineration is not much practiced for MSW in India due to the high moisture (40-60 %), organic content (40-60 %) and low calorific value of MSW ( kcal/kg). Incineration requires waste of atleast 1460 kcal/kg. The first large scale MSW incineration plant came into operation in Timarpur in It was operational for only 6 months and closed due to its poor performance. Timarpur-Okhla Waste Management Co Pvt Ltd (TOWMCL) started in Environmental problems associated: a) Release of pollutants like dioxins and furans (carcinogenic). b) Left over waste needs to be landfilled.

28 Generally, the feedstock requires some pre-processing to remove the inorganic materials (such as metals and glass) that cannot be gasified. Involves partial oxidation and temperature between C depending on the feedstock composition. Products: SYNGAS (mixture of CO and H2 predominantly along with traces of CO2, CH4 and other LMW hydrocarbons). Also contains a number of undesired components such as PM, tar, alkali, sulfide and chlorine. Gasification emissions are generally an order of magnitude lower than the emissions from an incinerator. GASIFICATION (Thermo-chemical conversion)

29 Applications of purified SYNGAS

30 PYROLYSIS (Thermo-chemical conversion) It is a thermochemical decomposition process conducted under oxygen-deficient conditions, typically at temperatures ranging between 300 C and 650 C. Products: char, bio-oil and condensable gases. Part of the condensable gases may further decompose into secondary products including CO, CO2, H2 and CH4. The pyrolytic liquid known as bio-oil as a result of condensation of volatiles can be utilized as a fuel product or as an intermediate for the synthesis of fine chemicals. The char can be used in a number of applications, including energy production and as soil amendment. The yields and composition of pyrolysis products depend on: a) Feedstock properties b) Pyrolysis temperature c) Heating rate: Slow or fast pyrolysis

31 Reference: Chen et al. (2014) Pyrolysis technologies for municipal solid waste: A review. 34:

32 TOWARDS A TWENTY-FIRST CENTURY LANDFILL BIOREACTOR LANDFILL TECHNOLOGY Conventional Landfill Basic principle: To contain & store waste. Takes about years for decomposition Leachate generation & release of landfill gas pose long term environmental risk. Bioreactor Landfill Basic principle: Treatment of waste along with energy capture. Takes about 5-10 years for decomposition Tackles the environmental problems associated with landfilling. Biogas generation potential from MSW in India is estimated to be 3369 million m 3 year -1 Dr. Pooja Ghosh

33 Fig. Schematic diagram of open dump simulator Fig. Schematic diagram of anaerobic bioreactor landfill simulator

34 BIOREACTOR LANDFILL TECHNOLOGY Currently there are no full-scale bioreactor landfills operational in India due to design and operational challenges along with cost associated with full-scale landfill bioreactor operation. PROS INCREASED METHANE RECOVERY RAPID WASTE STABILIZATION RECOVERY OF LANDFILL AIR SPACE ON SITE LEACHATE MANAGEMENT CONS INCREASED COST FOR LANDFILL DESIGN AND OPERATION LIMITED LEACHATE QUANTITIES FOR RECIRCULATION IN DRYER CLIMATES Dr. Pooja Ghosh REDUCTION IN COST ASSOCIATED WITH LONG TERM MONITORING AND MAINTENANCE OF THE LANDFILL

35 INITIATIVES TAKEN BY THE GOVERNMENT Swachh Bharat Mission (SBM) A Paradigm Shift in Waste Management and Cleanliness in India The aim is to have door-to-door collection of garbage in all 81,000 urban wards in India. So far, 41,000 wards have been covered. However, waste processing into compost or energy remains a bigger challenge of the programme. When Swachh Bharat Mission started, the waste processing had reached a level of 16%. Three years on, it is at 22%. Total estimated capacity of production of compost from municipal waste is 54 lakh tonnes, but so far installed capacity of compost generation is just 15 lakh. At present, there are 145 compost plants in operation and 200 are under construction. About 150 waste-to-energy projects are under construction.

36 Solid Waste Management Rules 2016 Segregation Of Waste Is Important As per the new rules, all waste generators should start segregating their waste into three categories Biodegradables, Dry Waste (Plastic, Paper, metal, Wood) and Domestic Hazardous Waste (diapers, napkins, mosquito repellents, cleaning agents) before they hand it over to the collectors. Introduction Of New Things User Fees And Spot Fines Under the new rules, waste generators will have to pay some amount to the waste collectors for activities like collection, disposal, and processing of waste. The local body across India has the authority to decide the User Fees. The rules also stipulate zero tolerance for throwing, burning or burying the solid waste generated on streets, open public spaces, water bodies, etc. Spot Fines are also introduced under these new rules which means if someone is found littering or disobeying the guidelines, then local bodies have the authority to fine them. A Bin Is A Must For Street Vendors All street vendor should keep suitable containers or bins for storage of the waste generated by them such as food waste, disposable plates, cups, cans, wrappers, coconut shells, leftover food, vegetables, fruits etc. They are also responsible for their own waste and should deposit their waste at a waste storage depot or container or vehicle as notified by the local authority. Guidelines For The Over-growing Landfills No non-recyclable waste having calorific value of 1500 Kcal/kg or more shall be disposed in the landfills. That waste can either be utilized for generating energy or can be used for preparing refuse derived fuel. It can also be used for coprocessing in cement or thermal power plants. As per the new rules, the landfill site should be 100 metres away from a river, 200 metres from a pond, 500 metres away from highways, habitations, public parks and water supply wells and 20 km away from airports/airbase.

37 Solid Waste Management Rules 2016 (contd.) Waste Processing And Treatment Guidelines The new rules advise that the bio-degradable waste should be processed, treated and disposed of through composting or bio-methanation within the premises as far as possible and the residual waste shall be given to the waste collectors or agency as directed by the local authority. The developers of Special Economic Zone, industrial estate, industrial park will also have to earmark at least 5 percent of the total area of the plot or minimum 5 plots/ sheds for recovery and recycling facility. The rules have also mandated bio remediation or capping of old and abandoned dump sites within five years. Involvement of Ragpickers The new rules help in the integration of ragpickers, waste pickers and kabadiwalas from the informal sector to the formal sector by the state government. Guidelines for Municipal authorities All local bodies are required to set up few by-laws regarding waste management, segregation of waste within their society. They are also required to set up a system in place so as the process of waste segregation can be followed smoothly by all waste generators. They are also required to promote the idea of composting, waste segregation and waste management through different educative campaigns. The Process Of Monitoring The government has also established a Central Monitoring Committee under the chairmanship of Secretary, MoEF&CC to monitor the overall implementation of the rules effectively. It is advised that the committee comprising of various stakeholders from the central and state governments will meet once a year to discuss and monitor the implementation of these rules.

38 Sustainability is taken seriously in Sweden. Very little household waste is actually wasted in Sweden less than 1 percent. The other 99 percent is recycled into new products, raw materials, or incinerated and used for gas or heat. Renewable energy sources account for nearly half (48 per cent) of Swedish energy production. In 2015, Sweden imported 2.3 million tonnes of waste from, among others, Norway, the UK and Ireland.

39 Pune MCD s Biogas Initiative - Solution to food waste with the bonus of eco-fuel

40 Leadership n Governance

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