Module 1solid waste managment and mitigation.pptx

sources and types of solid waste

1. Module 1b Sources and types of solid waste Sampling and characterization Determination of composition of MSW Storage and handling of solid waste

2. Importance of waste characterization: It is necessary to monitor and control existing waste management systems and to make regulatory, financial, and institutional decisions.

3. Waste hierarchy Waste hierarchy refers to 3 Rs Reduce, Reuse, Recycle

4. Waste Minimizing solid waste Minimizing packaging Recycleable Paper, plastics, metals, glass, wood Reusable ? Textiles, leather, rubber, metals, wood Compostable Yard trimmings, food scraps (vegetable)

5. Basic terminologies used in Solid waste Management Ash : the non-combustible solid by-products of incineration or other burning process Bulky waste: large wastes such as appliances, furniture, and trees and branches, that cannot be handled by normal MSW processing methods Co-disposal : the disposal of different types of waste in one area of a landfill or dump. For instance, sewage sludges may be disposed of with regular solid wastes

6. Biodegradable material : any organic material that can be broken down by microorganisms into simpler, more stable compounds . Most organic wastes (e.g., food, paper) are biodegradable Compost : the material resulting from composting . also called humus, is a soil conditioner and in some instances is used as a fertilizer Composting : biological decomposition of solid organic materials by bacteria, fungi, and other organisms into a soil-like product . Putrescible : subject to decomposition or decay. Usually used in reference to food wastes and other organic wastes that decay quickly

7. Garbage : Putrescent organic matter such as kitchen or food scraps Rubbish/trash:  a broad category of dry goods including boxes, bottles, tin cans, or virtually anything made from wood, metal, glass, and cloth, could be transformed into new consumer products through a variety of reclamation methods Refuse : all kinds of wastes in solid state excepting excreta from residential, commercial and industrial area Refuse-derived fuel (RDF) : fuel produced from MSW that has undergone processing. Processing can include separation of recyclables and non-combustible materials, shredding, size reduction, and pelletizing

8. Disposal : the final handling of solid waste, following collection, processing, or incineration. Disposal most often means placement of wastes in a dump or a landfill Environmental impact assessment (EIA) : an evaluation designed to identify and predict the impact of an action or a project on the environment and human health and well-being. Can include risk assessment as a component, along with economic and land use assessment Environmental risk assessment ( EnRA ) : an evaluation of the interactions of agents, humans, and ecological resources. Comprised of human health risk assessment and ecological risk assessment , typically evaluating the probabilities and magnitudes of harm that could come from environmental contaminants.

9. Landfilling : the final disposal of solid waste by placing it in a controlled fashion in a place intended to be permanent. The Source Book uses this term for both controlled dumps and sanitary landfills Leachate : liquid that has seeped through a landfill or a compost pile and has accumulated bacteria and other possibly harmful dissolved or suspended materials MSW : municipal solid waste MSWM : municipal solid waste management

10. Waste-to-energy (WTE) plant : a facility that uses solid waste materials (processed or raw) to produce energy. WTE plants include incinerators that produce steam for district heating or industrial use, or that generate electricity ; they also include facilities that convert landfill gas to electricity

11. Waste sources and types There are eight major classifications of solid waste generators based on waste source: Residential Industrial Commercial Hospitals/ Institutions Construction and Demolition Municipal services Process Agricultural

12. Types of solid wastes Typical waste generators Source Food wastes, paper, cardboard, plastics, textiles, leather, yard wastes, wood, glass, metals, ashes, special wastes (e.g., bulky items, consumer electronics, white goods, batteries, oil, tires), and household hazardous wastes Single and multifamily dwellings Residential Housekeeping wastes, packaging, food wastes, construction and demolition materials, hazardous wastes, ashes, special wastes Light and heavy manufacturing, fabrication, construction sites, power and chemical plants Industrial All of the above should be included as “municipal solid waste.” Classification of Solid waste

13. Types of solid wastes Typical waste generators Source Paper, cardboard, plastics, wood, food wastes, glass, metals, special wastes, hazardous wastes Stores, hotels, restaurants, markets, office buildings, etc. Commercial Same as commercial Schools, hospitals, prisons, government centers Hospitals/Institutional Wood, steel, concrete, dirt, etc. New construction sites, road repair, renovation sites, demolition of buildings Construction and Demolition All of the above should be included as “municipal solid waste.”

14. Types of solid wastes Typical waste generators Source Street sweepings; landscape and tree trimmings; general wastes from parks, beaches, and other recreational areas; sludge Street cleaning, landscaping, parks, beaches, other recreational areas, water and wastewater treatment plants Municipal services Industrial process wastes, scrap materials, off-specification products, slag, tailings Heavy and light manufacturing, refineries, chemical plants, power plants, mineral extraction and processing Process All of the above should be included as “municipal solid waste.”

15. Spoiled food wastes, agricultural wastes, hazardous wastes (e.g., pesticides) Crops, orchards, vineyards, dairies, feedlots, farms Agriculture

16. Socioeconomic development Degree of industrialization Climate or seasons Geographical location\Collection frequency Population diversity Public attitude Legislation Factors Influence Waste Generation Rates

17. Greater the economic wealth and the higher percentage of urban population, the greater the amount of solid waste produced Low income countries have the lowest percentage of urban populations and the lowest waste generation rates,

18. Figure 1: Waste Composition of Low, Middle, and High Income Countries

19. Major deficiencies Littering of garbage due to unorganized primary collection Provision and operation of interim storage facilities unsatisfactory Irregular garbage lifting Transportation system not synchronize with storage facilities Processing / treatment of MSW not practiced Final disposal through dumping and not SLF

20. Composition of Solid waste In India Source: CPHEEO Manual on MSW, 2005

21. Composition of Solid waste in India The composition of municipal waste varies greatly from country to country and changes with time .

22. Characteristics of Solid waste Physical Specific weight, Moisture content, Particle size and size distribution, Field capacity, Compacted waste porosity (permeability) Chemical Important in evaluating alternative processes and recovery options Proximate analysis, Fusing point of ash, Ultimate analysis (major elements), Energy content Biological Important in considering organic fractions Corresponding to Biodegradability Production of odor

23. 24 Physical Properties Specific weight Weight of material per unit volume kg/m 3 , lb /yd 3 , etc. Sometime, referred as “density” Often reported as loose, compacted, non-compacted, as found in containers Depend on G eographic location Season of the year Length of time in storage For example, waste in compaction vehicle Typical range = 178 – 415 kg/m 3 Average = 297 kg/m 3

24. 25 Specific weight of MSW Components Condition Specific weight (kg/m 3 ) Aluminum cans Loose 30 - 44 Flattened 149 Corrugated cardboard Loose 208 Fines (dirt, etc.) Loose 321 - 950 Food waste Loose 131 - 481 Baled 594 - 712 Glass bottles Whole bottles 297-416 Crushed 1068 - 1602 Magazines Loose 475 Newsprint Loose 12 - 33 Baled 428 - 594 Office paper Loose 238 Baled 416 - 445

25. 26 Specific weight of MSW Components Condition Specific weight (kg/m 3 ) Plastics Mixed 42 - 131 PETE, whole 18 - 24 Baled 250 - 297 HDPE, loose 15 Flattened 39 Plastic film and bags Baled 297 - 475 Granulated 416 - 445 Steel cans Unflattened 89 Baled 505 Textiles Loose 42 - 101 Yard waste Mixed, loose 149 - 297 Leaves, loose 30 - 149 Grass, loose 208 - 297

26. Moisture Content Moisture content : expressed in Wet –weight methods Expressed as percentage of the wet weight of the material Dry-weight methods Expressed as percentage of the dry weight material Wet weight method is commonly used 100 M: moisture content, % w: initial weight of the sample, kg d: weight of sample after drying at 105 °C, kg  

27. Moisture content varies generally from 20 to 45% depending upon the climatic conditions and level of city (income group) etc. The increase of moisture content increases the weight and thus the cost of transportation and thus the storage section should take care of it.

28. 29 Moisture Content of MSW Component Moisture content, % Range Typical Residential Aluminum cans Cardboard Fines (dirt, etc.) Food waste Glass Grass Leather Leaves Paper Plastics Rubber Steel cans Textiles Wood Yard waste 2-4 4-8 6-12 50-80 1-4 40-80 8-12 20-40 4-10 1-4 1-4 2-4 6-15 15-40 30-80 3 5 8 70 2 60 10 30 6 2 2 3 10 20 60 Component Moisture content, % Range Typical Commercial Food waste Mixed Wood crates and pallets 50-80 10-25 10-30 70 15 20 Construction (mixed) 2-15 8

29. 30 Physical Properties- particle Size distribution Component Food waste Paper Cardboard Plastics Textiles Rubber Leather Yard wastes Wood Glass Tin cans Aluminum Other metal Dirt, ash, etc. Range and modal value Typical component size, in

30. 31 Physical Properties Field capacity Total amount of moisture that can be retained in a waste sample subject to downward pull of gravity Critical importance: Determining the formation of landfill leachate Water in excess will be released as leachate Depend on Applied pressure State of decomposition of waste Expressed as Percentage in volume e.g. 30% Permeability of compacted wastes Or “hydraulic conductivity” Important in governing the movement of gases and liquid in landfill site

31. 32 Chemical Properties Determining alternative processing + recovery options For example Combustion, composting, etc. To use MSW as fuel, it is to consider Major properties: Proximate analysis Fusing (melting) point of ash Ultimate analysis (major elements) Trace elements are important if MSW is recovered as feedstock Energy content

32. Chemical Properties Proximate analysis := Analysis for combustible components Moisture content Loss of moisture at 105 o C for 1 hr Volatile combustible matter Loss of weight on ignition at 950 o C in a covered crucible Fixed carbon Combustible residue left after removal of volatile matter Ash Weight of residue after combustion in an open crucible Solid Wastes Combustible Volatile combustible Fixed carbon Ash Non- combustible H 2 O

33. 34 Chemical Properties Type of waste Proximate analysis, % by weight Moisture Volatile matter Fixed carbon Non- combustible Food and food products Fats 2.0 95.3 2.5 0.2 Food wastes (mixed) 70.0 21.4 3.6 5.0 Fruit wastes 78.7 16.6 4.0 0.7 Meat wastes 38.8 56.4 1.8 3.1 Paper products Cardboard 5.2 77.5 12.3 5.0 Magazines 4.1 66.4 7.0 22.5 Newsprint 6.0 81.1 11.5 1.4 Paper (mixed) 10.2 75.9 8.4 5.4 Waxed cartons 3.4 90.9 4.5 1.2

34. 35 Chemical Properties Type of waste Proximate analysis, % by weight Moisture Volatile matter Fixed carbon Non- combustible Plastics Plastics (mixed) 0.2 95.8 2.0 2.0 Polyethylene 0.2 98.5 <0.1 1.2 Polystyrene 0.2 98.7 0.7 0.5 Polyurethane 0.2 87.1 8.3 4.4 Polyvinyl chloride 0.2 86.9 10.8 2.1 Textiles, rubber, leather Textiles 10.0 66.0 17.5 6.5 Rubber 1.2 83.9 4.9 9.9 Leather 10.0 68.5 12.5 9.0

35. 36 Chemical Properties Type of waste Proximate analysis, % by weight Moisture Volatile matter Fixed carbon Non- combustible Wood, trees, etc. Yard wastes 60.0 30.0 9.5 0.5 Wood (green timber) 50.0 42.3 7.3 0.4 Hardwood 12.0 75.1 12.4 0.5 Wood (mixed) 20.0 68.1 11.3 0.6 Glass, Metals, etc. Glass and mineral 2.0 - - 96-99+ Metal, tin cans 5.0 - - 94-99+ Metal, ferrous 2.0 - - 96-99+ Metal, nonferrous 2.0 - - 94-99+

36. 37 Chemical Properties Type of waste Proximate analysis, % by weight Moisture Volatile matter Fixed carbon Non- combustible Miscellaneous Office sweepings 3.2 20.5 6.3 70.0 Residential MSW 21.0 (15-40) 52.0 (40-60) 7.0 (4-15) 20.0 (10-30) Commercial MSW 15.0 (10-30) - - MSW 20.0 (10-30) - -

37. 38 Chemical Properties Fusing Point of Ash Temperature that cause ash (from burning wastes)  form a solid (clinker) by fusion and agglomeration Typical range = 1,100 – 1,200 o C May cause operational problems in incineration processes

38. 39 Chemical Properties Ultimate analysis To determine chemical composition C, H, O, N, S and ash Halogen group Cl, Br,... Data is used for Determine C/N ratio for composting or biological conversion processes Awareness of chlorinated compounds Dioxin, Furan, etc.

39. 40 Chemical Properties – Ultimate analysis Component Percent by weight (dry basis) Carbon Hydrogen Oxygen Nitrogen Sulfur Ash Organic Food wastes Paper Cardboard Plastics Textiles Rubber Leather Yard wastes Wood 48.0 43.5 44.0 60.0 55.0 78.0 60.0 47.8 49.5 6.4 6.0 5.9 7.2 6.6 10.0 8.0 6.0 6.0 37.6 44.0 44.6 22.8 31.2 - 11.6 38.0 42.7 2.6 0.3 0.3 - 4.6 2.0 10.0 3.4 0.2 0.4 0.2 0.2 - 0.15 - 0.4 0.3 0.1 5.0 6.0 5.0 10.0 2.5 10.0 10.0 4.5 1.5 Inorganic Glass Metals Dirt, ash, etc. 0.5 4.5 26.3 0.1 0.6 3.0 0.4 4.3 2.0 <0.1 <0.1 0.5 - - 0.2 98.9 90.5 68.0

40. 41 Chemical Properties Energy content Determined by Full-scale boiler as a calorimeter Laboratory bomb calorimeter Calculation of elemental composition ( Dulong Formula) Btu/ lb = 145C + 610(H 2 – 1/8O 2 ) + 40S + 10N E lement  percent by weight Btu/ lb ＝ 5/9 kcal/kg = 2.326 kJ/kg Trace elements K, Ca Mg, Zn, Mn , Cu, Co, Ni, etc. Important for the production of biological conversion products as the essential nutrient Contents of final products

41. 42 Chemical Properties – Energy contents Inert residue, percent Energy, Btu/lb Range Typical Range Typical Organic Food wastes Paper Cardboard Plastics Textiles Rubber Leather Yard wastes Wood 2-8 4-8 3-6 6-20 2-4 8-20 8-20 2-6 0.6-2 5.0 6.0 5.0 10.0 2.5 10.0 10.0 4.5 1.5 1,500-3,000 5,000-8,000 6,000-7,500 12,000-16,000 6,500-8,000 9,000-12,000 6,500-8,500 1,000-8,000 7,500-8,500 2,000 7,200 7,000 14,000 7,500 10,000 7,500 2,800 8,000 Inorganic Glass Tin cans Aluminum Other metals Dirt, ash, etc. 96-99+ 96-99+ 90-99+ 94-99+ 60-80 98.0 98.0 96.0 98.0 70.0 50-100 100-500 - 100-500 1,000-5,000 60 300 - 300 3,000 MSW 4,000-6,000 5,000 Btu/lb ＝ 5/9 kcal/kg = 2.326 kJ/kg

42. Calorific Value Calorific value is the amount of heat generated from combustion of a unit weight of a substance, expressed as kilo calorie per kilogram The calorific value is determined in the laboratory by Bomb Calorimeter.

43. 44 Biological Properties Organic fractions of MSW, excluding plastic, rubber, and leather Water-soluble constituents Sugars, starches, amino acid, organic acids, etc. Hemicellulose Cellulose Fats, oil, and waxes Lignin Lignocellulose Protein However, the important biological properties are to determine Biodegradability of organic fractions Production of odors, Breeding of flies

44. 45 Biological Properties Biodegradability of organic fractions Determined by volatile solid (VS) content Ignition at 550 o C But, may misinterpret for some components Newsprint  high VS but low biodegradability Food wastes  low VS but high biodegradability Consider percent of lignin in the VS BF = 0.83 – 0.028 LC BF = biodegradable fraction LC = lignin content of VS (% dry weight) Often, express in “rapidly” or “slowly” decomposable

45. 46 Biological Properties Production of odors Significant in a long storage and warm climate Resultant of anaerobic decomposition readily decomposable organic component SO 4 -2  reduced to sulfide (S 2- ) + combine with H  H 2 S Biochemical reduction of an organic compound containing with S radical Produce methyl mercaptan + aminobutyric acid  malodorous Methyl mercaptan  reduced + form H 2 S Breeding of flies Flies can develop after < 2week of egg laid Very important consideration but very difficult to control, especially in the tropical areas

46. 47 Applications of MSW Properties & Composition To determine Appropriate transformation processes Separation, reduction, combustion, composting, etc. Improving efficiencies transformation processes E.g. moisture content + C/N  composting reactions To design recovery methods Reuse + recycling materials Conversion products + energy

47. 48 Transformation process for MSW management Transformation processess Transformation means or methods Transformation or principal conversion products Physical Component separation Manual and/or mechanical separation Individual components found in commingled MSW Volume reduction Application of energy in the forms of force or pressure The original waste reduced in volume Size reduction Application of energy in the forms of shredding, grinding or milling The original waste components altered in form and reduced in size

48. 49 Transformation process for MSW management Transformation processes Transformation means or methods Transformation or principal conversion products Chemical Combustion Thermal oxidation CO 2 , SO 2 , other oxidation products, ash Pyrolysis Destructive distillation A gas stream containing a variety of gases, tar and/or oil, and a char Gasification Starved air combustion A low-energy gas, a char containing carbon and the inert originally in the fuel and oil

49. 50 Transformation process for MSW management Transf ormation processes Transformation means or methods Transformation or principal conversion products Biological Aerobic composting Aerobic biological conversion Compost (humus-like material used as a soil conditioners) Anaerobic digestion (low- or high-solids) Anaerobic biological conversion Methane (CH 4 ), CO 2 , trace gases, digested humus or sludge Anaerobic composting (normally occur in landfills) Anaerobic biological conversion Methane (CH 4 ), CO 2 , digested waste

50. 51 A typical solid waste management system in developing countries Storage Collection and transport Recycling Intermediate storage Disposal But, less Transformation Recovery Minimization Conversion to energy ( Adapted from Zurbrügg , 2003)

51. Problems Composition of MSW