Solid waste management

1. Lecture 13 – Solid Waste
Management
Dr. Stephen
Assistant Professor
Crop Physiology
School Of Agricultural Sciences,
Anurag University

2. Classification
1) Municipal Solid Wastes (MSW)
2) Industrial wastes
3) Hazardous wastes
4) Biomedical/Hospital wastes
5) Agricultural wastes

3. Municipal Solid Waste (MSW)

4. Municipal solid wastes (MSW)
 Non-hazardous solid waste from a city, town
or village that requires routine collection and
transport to a processing or disposal site
Sources
 Homes
 Commercial establishments and institutions

5. Composition
1) Wet Garbage
- Food waste (vegetable and meat)
2) Dry Garbage
- Paper, plastic, glass bottles, cardboard boxes,
aluminum foil, metal items, wood pieces

6. Degeneration time of domestic wastes
S.no. Common domestic wastes Approximate time for
degeneration
1) Organic kitchen waste
vegetables, fruits
1-2 weeks
2) Paper, cardboard paper 15 days – 1 month
3) Cotton clothes 2-5 months
4) Woolen clothes About a year
5) Metal cans, tin, aluminum 100-500 years
6) Plastics 1 million years

7. Components of municipal solid waste
management
1) Recycling
2) Composting
3) Land-filling
4) Waste-to-energy via incineration

8. Steps in MSW management
1) Generation
2) Collection
3) Sorting and Separation
4) Transfer
5) Disposal/Utilisation

9. Regeneration/Recycling
 Materials Recovery Facilities (MRF)

10. Sanitary Landfill
 It is an engineered facility used for disposing off
solid wastes on land without creating nuisances
or hazards to public health or safety

11. Energy Generation
 Cleaner and economical
Technologies for energy generation
1) Landfill gas capture
2) Combustion
3) Pyrolysis
4) Gasification
5) Plasma arc gasification

12. Constraints
 Administrative and institutional failure rather
than a technological one
Stakeholders
 Urban governments
 Citizens
 Institutions

13. Hazardous Wastes

14. Hazardous wastes
 These are wastes that can cause harm to human and the environment
Characteristics of hazardous wastes
1) Physical or chemical properties of toxicity
2) Reactivity
3) Ignitability
4) Corrosivity

15. Toxic wastes
 Poisonous in small or trace amounts
 Acute or immediate effect on human or animals
 Carcinogenic or mutagenic causing biological
changes in the children of exposed people and
animals
 Eg: Pesticides, heavy metals

16. Reactive wastes
 Tendency to react vigorously with air or water
 They are unstable to shock or heat
 Generate toxic gases
 Explode during routine management
 Eg: Gun powder, nitroglycerine

17. Ignitable wastes
 They burn at relatively low temperatures (< 60 °C)
 They are capable of spontaneous combustion
during storage, transport or disposal
 Eg: Gasoline, paint thinners and alcohol

18. Corrosive wastes
 They destroy materials and living tissues by
chemical reactions
 Eg: Acids and Bases

19. Infectious wastes
 Human tissues from surgery, used bandages
 Hypoderm needles, hospital wastes

20. Sources
 Chemical manufacturing companies
 Petroleum refineries
 Paper mills
 Smelters
 Plastic industries

21. Effects
 Contamination of groundwater
 Pesticide residues in soil wash into rivers and
streams
 The residues may persist as PCBs (Polychlorinated
Biphenyls) that are concentrated in kidneys and
liver causing their damage
 Inhalation, ingestion or skin contact result in chronic
or acute poisoning

22. Effects – Lead poisoning
 The heavy metal lead is accumulated in the
bones
 Lead affects red blood cells by reducing their
ability to carry oxygen and shortening their life
span
 It affects nervous tissues causing brain disease

23. Effects (cont.)
Mercury
 Mercury buildup in the body also results in brain
damage
 Minamata disease occurs due to mercury
poisoning
Plastic
 Exposure to vinyl chloride used in plastic
manufacture can cause deafness, vision
problem, circulation disorders and bone
deformities

24. Control
 Manufacturing industries should change their
protocols to generate less hazardous wastes
 Substitution of PCBs and vinyl chloride with
chemicals that are less toxic

25. Industrial Wastes

26. Industrial wastes
 They are very toxic and require special
treatment
Sources
1) Food processing industries
2) Metallurgical chemical units
3) Pharmaceutical units
4) Breweries
5) Sugar mills
6) Paper and pulp industries
7) Fertilizer and pesticide industries

27. Effects
 Health of people surrounding the dumping sites is
severely affected
 Exposure may cause disorders of nervous system,
genetic defects, skin diseases and even cancer
 The liquid effluents from the industries contain
organics and inorganic pollutants

28. Effects (Cont.)
 The effluents cause deterioration of water bodies
 Pollution of ground water, formation of
sediments, fish population
 Foul odours

29. Control
 Waste minimization technologies have to be
developed
 Source reduction, recycling, reuse of
materials need to be practiced on a large
scale
 Hazardous waste should not mix up with
general waste

30. Control (cont.)
 Source reduction involves altering the design,
manufacture or use of products & materials to
reduce the amount and toxicity of materials
that get thrown away
 Land-filling, incineration & composting
technologies to be followed

31. Case Study: Love Canal Tragedy

32. Agricultural Wastes

33. Sources
 Crops
Eg: Rice husk, degasses, groundnut shell, straw of shells
 Livestock
 Agro-based industries
Eg: rice milling, tea production, tobacco

34. Management
- Waste to Energy
1) Gasification
 Chemical decomposition of biomass in the
presence of oxygen
 The gas produced is used in engines to produce
electricity
 Eg: Rice husks, groundnut shells

36. 2) Pyralysis
 Chemical decomposition of biomass wastes in the
absence of oxygen at high temperatures
 The resulting gas is used for power generation

37. 3) Biogas production
 Animal wastes, food processing wastes and other
organic matter are decomposed to produce a gas
called biogas
 Biogas contains methane and CO2
 The byproduct in the process is slurry, which can
be used as manure

38. 4) Sustainable products
 Agricultural wastes like corn cobs, paddy husk,
bagasse of sugarcane, waste of wheat, rice and
other cereals, cotton stalks, coconut wastes, jute
waste
 Used in making paper and hardboard

39. 3 R’s principle of minimizing waste
production
1) Reduce
 Reduce the amount and toxicity of
garbage and trash that you discard
2) Reuse
 Reuse containers or materials
 Try to repair things that are broken
3) Recycle
 Recycle products wherever possible
 Buy recycled products