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Dr. Pooja GhoshDST Inspire FacultyCRDT, IIT-D
Energy recoveryfrom
Municipal solid 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.
How we define waste?
“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
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.
MSW
Organics (Kitchen waste,
Agro waste, Garden waste)
Inert (Sand, Pebbles, Gravel)
Recyclables (Plastic, Paper, Tin cans, Metal, Glass, Syringes)
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
2025.
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.
Waste Generation in India
India is growing; and so are themountains of waste its cities and villagesare generating.
CPCB Report, 2015:India produces approximately 52 milliontonnes of waste each year (0.144 milliontonnes per day).
Table 1 Major cities of India and per capita waste generation data (2010-2011)
Source: Census of India 2011, CPCB Report 2011.
Table 2 Waste generation per capita in Indian cities
Source: Kumar et al., 2017
9,000 TPD
17,000-
25,000 TPD
Delhi MSW
generation (2016)
Projected Delhi MSW
generation (2021)
The World Bank
estimates that by 2025
solid waste generation
in India will rise by 243
per cent.
Waste Composition in India
CPCB (2015)estimates
90 % Indian cities
dispose their waste
in landfills.
Methane
emissions
Leachate
discharge
Landfills in India Non-EngineeredNo BaselinersNo Leachate Collection SystemNo CH4 capture
Diagram of an Engineered landfill
LeachateCause of Concern!Ø Dissolved organic matter
Ø Inorganic macro components
Ø Heavy metals
Ø Xenobiotic organic
compounds
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. 22:9148-9158.
Does urban MSW affect rural areas?
Peri-urban or Intermediately Ruralareas are the new targets for dumpingsolid wastes. For eg. Landfill sites atMavallipura and Mandur villages nearBangalore.
September 11, 2014
So what is
the solution
for WM ?
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
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.
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.
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 eco-
friendly garbage management facilities.
NO MORE DUMPING IN UNENGINEERED LANDFILL SITES
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
MSW TO ENERGY TECHNOLOGIES
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.
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- 6.8-7.2
C/N Ratio: Desirable- 20-30:1
Bacterial population
Organic loading rate
Hydraulic Retention time
METHANE PRODUCTION POTENTIAL OF DIFFERENT MSW
Reference: Matsakas et al. (2017) Green conversion of municipal solid wastes into fuels and chemicals. Electronic Journal of Biotechnology 26, 69–83.
Pre-treatment
Co-digestion
Additives
INCINERATION
(Thermal conversion)
Involves complete combustion of solid waste at high temperature (700-1400 ˚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 80-90 %.
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 (600-1100 kcal/kg).
Incineration requires waste of atleast 1460 kcal/kg.
The first large scale MSW incineration plant came into operation in Timarpur in
1987. It was operational for only 6 months and closed due to its poor performance.
Timarpur-Okhla Waste Management Co Pvt Ltd (TOWMCL) started in 2010.
Environmental problems associated:
a) Release of pollutants like dioxins and furans (carcinogenic).
b) Left over waste needs to be landfilled.
GASIFICATION
(Thermo-chemical conversion)
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 800-1200 ˚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.
Applications of purified SYNGAS
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
Reference: Chen et al. (2014) Pyrolysis technologies for municipal solid waste: A review. 34: 2466-2486.
TOWARDS A TWENTY-FIRST CENTURY LANDFILL
BIOREACTOR LANDFILL TECHNOLOGY
Conventional Landfill Bioreactor Landfill
Basic principle: To
contain & store waste.
Takes about 30-50
years for
decomposition
Leachate generation &
release of landfill gas
pose long term
environmental risk.
Basic principle:
Treatment of waste
along with energy
capture.
Takes about 5-10
years for
decomposition
Tackles the
environmental
problems associated
with landfilling.
Dr. Pooja Ghosh
Biogas generation potential from MSW in
India is estimated to be 3369 million m3 year-1
Fig. Schematic diagram of open dump
simulatorFig. Schematic diagram of anaerobic
bioreactor landfill simulator
BIOREACTOR LANDFILL
TECHNOLOGY
PROS
INCREASED METHANE RECOVERY
RAPID WASTE STABILIZATION
RECOVERY OF LANDFILL AIR
SPACE
ON SITE LEACHATE MANAGEMENT
REDUCTION IN COST ASSOCIATED WITH LONG TERM MONITORING AND MAINTENANCE OF THE LANDFILL
CONS
INCREASED COST FOR LANDFILL DESIGN AND OPERATION
LIMITED LEACHATE QUANTITIES FOR
RECIRCULATION IN DRYER CLIMATES
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.
Dr. Pooja Ghosh
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.
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 co-
processing 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.
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.
Solid Waste Management Rules 2016 (contd.)
Sustainability is taken seriously in Sweden.Very little household waste is actuallywasted in Sweden — less than 1 percent.The other 99 percent is recycled into newproducts, raw materials, or incinerated andused for gas or heat. Renewable energysources account for nearly half (48 per cent)of Swedish energy production.In 2015, Sweden imported 2.3 million tonnesof waste from, among others, Norway, the UKand Ireland.
Pune MCD’s Biogas Initiative - Solution to food waste with the bonus of eco-fuel
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