Environmental Management Lecture 11: Waste Management

Environmental Management - Lecture 11: Solid Waste Management

• Solid waste is a resource in the wrong place at the wrong time. Proper use can make it a valuable resource.

• Jane Jacobs predicted urban waste could be a future gold mine.

• Poerbo (1991) highlights the importance of balancing health, environmental, and economic aspects of waste management.

• Global waste generation is projected to increase substantially by 2030 and 2050. North America, Latin America and the Caribbean, Middle East & North Africa, Sub-Saharan Africa, South Asia, and Europe and Central Asia show significant regional variations in waste generation. (Data shown in millions of US tons)

• The transition to disposable containers started before WWII and was finalized in the 1980s, beginning with soda/beer containers, extending to razors, diapers, pens, and cigarette lighters by the 1970s.

• In the past, milk, soda, and beer bottles were regularly returned and re-used.

• Grocery stores used brown paper bags that could be reused creatively, such as for school book covers. Babies’ diapers were washed. Clothes were dried on lines rather than energy-intensive machines.

• Fragile items were packaged with old newspapers, water was collected from fountains instead of plastic bottles, writing pens were refilled, and razor blades were replaced.

Types of Waste

• Liquid Waste: Waste in non-solid forms; includes storm water, wastewater, wash water from homes, industrial cleaning liquids, and waste detergents. Some solid waste can be converted to liquid waste for disposal.

• Solid Waste: Garbage and refuse, sludge from water/wastewater treatment plants and air pollution facilities, discarded materials (solid, liquid, semi-solid, or gaseous) from industrial, commercial, mining, agricultural and community activities. Hazardous or non-hazardous.

Municipal Solid Waste Source

• Municipal solid waste comes from residential, commercial, institutional and industrial sources.
  • Types include plastic, glass, metal, and tires

Composition of Municipal Solid Waste

• Municipal Solid Waste (MSW) contains varying percentages of materials:
  • Paper and paperboard (27%)
  • Yard trimmings (14%)
  • Food waste (13%)
  • Plastics (13%)
  • Metals (9%)
  • Rubber, leather and textiles (9%)
  • Wood (6%)
  • Glass (5%)

Solid Waste Characteristics

• Physical and chemical composition of solid waste varies depending on the sources.

• Landfill waste characteristics affect gas and leachate production and composition, factors such as degradable vs nondegradable components, moisture content, and the bio-degradable element.

• Waste composition impacts both bulk gases and trace components.

• Solid waste is complex multiphase mixtures whose composition analysis is not easy.

• Random sampling techniques are often used for determining composition.

• Waste is reduced to ~100 kg using standard coning and quartering procedures for analysis.

Waste Characteristics - Physical and Chemical

• Physical characteristics include density, moisture content, size distribution of components, color voids, shape of components, particle size, optical and magnetic properties, field capacity, and compacted waste porosity.

• Chemical characteristics include moisture content (water content), volatile matter, fixed carbon, fusing point of ash, calorific value (energy content), oxygen, sulphur and ash percentage.

Waste Characteristics - Biological

• The primary biological characteristic of MSW's organic fraction is its biodegradability (convert to gases and inert solids).
• Odors and fly breeding relate to the putrescible nature of organic materials like food waste.

Types of Waste - Hazardous

• Hazardous waste includes harmful or potentially harmful materials. This includes waste that is flammable, reactive, corrosive, and/or toxic. Examples include fire extinguishers, old propane tanks, pesticides, mercury containing equipment, thermostats, lamps (fluorescent bulbs) and batteries.

Types of Waste - Organic

• Organic waste comes from plants and animals. This typically includes food waste, fruit and vegetable peels, flower trimmings, and animal waste (e.g., dog poop).
• Organic waste is biodegradable.
• Many people compost organic waste for use in gardens.

Types of Waste - Recyclable

• Recyclable waste can be reprocessed into new materials. Examples include aluminum products, plastic materials, glass, paper products, and cardboard boxes.

Sources of Waste

• Municipal: Trash from households, schools, offices, markets, restaurants, and other public places (food waste, plastic bags, soda cans, plastic water bottles, broken furniture, grass clippings, packaging, broken appliances, and clothing)

• Medical/Clinical: Waste from healthcare facilities—hospitals, clinics, surgical theatres, veterinary hospitals, and labs (surgical items, pharmaceuticals, blood, body parts, wound dressing, needles, and syringes)

  • Different materials of waste have specific waste disposal procedures, for example, soilled anatomical and chemical liquid/cytotoxic waste.
  • Different waste sources are separated to appropriate disposal procedures.

• Agricultural: Waste generated by agriculture, including empty pesticide containers, old silage wrap, out-of-date medicines/wormers, used tires, surplus milk, cocoa pods, and corn husks.

• End-of-life automobiles: Old and broken cars, trucks, buses and rickshaws.

• Industrial: Waste created by industrial processes and production—glass, leather, textiles, food, electronics, plastics, and metals.

• Construction/Demolition: Waste from road and building construction and demolition, including concrete debris, wood, earth, large boxes, and plastics from building materials

• Electronic: Waste from electronic devices, also known as e-waste (TVs, computers, electronics). Contains lead, mercury, cadmium, and brominated flame retardants.

Effects of Waste & Poor Waste Disposal

• Environmental: Surface water, soil contamination
• Economic: Reduced municipal wellbeing (poor sanitation, lack of hygiene, negative impact from poor waste disposal) and decreased recycling revenue (lack of appropriate waste management systems = reduction in jobs, recycling, and composting operations)
• Social/Public Health: Pollution resulting from bad waste management can cause adverse respiratory problems and other health concerns as contaminants get absorbed into the body. Leachate (liquid from contaminated areas) is harmful; it is a mixture of chemicals that can lead to contamination of surface water, ground water, or soil.

This quiz covers the key concepts from Lecture 11 of Environmental Management, focusing on solid waste management. It explores the prediction of urban waste as a valuable resource, the historical context of waste generation, and the global variations in waste production. Additionally, it emphasizes the importance of balancing health, environmental, and economic factors in addressing waste issues.