Lesson 15 - Solid Wastes and Its Management

• Solid waste - Any discarded material that is abandoned by being disposed of, burned or incinerated, recycled or considered "waste-like".
• A solid waste can physically be a solid, liquid, semi-solid, or container of gaseous material.
• Organic waste: Kitchen waste, waste from food preparation, vegetables, flowers, leaves, fruits, and market places.
• Combustibles: Paper, wood, dried leaves, packaging for relief items etc. that are highly organic and having low moisture content.
• Ashes or Dust: Residue from fires that are used for cooking.
• Dead animals: Carcasses of dead livestock or other animals.
• Soiled waste: Hospital waste such as cloth soiled with blood and other body fluids.
• Solid waste management - Refers to the collecting, treating, and disposing of solid material that is discarded because it has served its purpose or is no longer useful.
• Improper disposal of municipal solid waste can create unsanitary conditions, and these conditions in turn can lead to pollution of the environment and to outbreaks of vector-borne disease —that is, diseases spread by rodents and insects.
• Modern landfills are designed in such a way that the bottom of the landfill is covered with an impervious liner, which is usually made of several layers of thick plastic and sand.
• Modern landfills are designed in such a way that the bottom of the landfill is covered with an impervious liner, which is usually made of several layers of thick plastic and sand.
• Sanitary Landfill - Modern landfills are designed in such a way that the bottom of the landfill is covered with an impervious liner, which is usually made of several layers of thick plastic and sand. This liner protects the groundwater from being contaminated because of leaching or percolation.  When the landfill is full, it is covered with layers of sand, clay, topsoil and gravel to prevent seepage of water. 
• Sanitary Landfill - Modern landfills are designed in such a way that the bottom of the landfill is covered with an impervious liner, which is usually made of several layers of thick plastic and sand. This liner protects the groundwater from being contaminated because of leaching or percolation.  When the landfill is full, it is covered with layers of sand, clay, topsoil and gravel to prevent seepage of water. 
• Incineration - This method involves the burning of solid wastes at high temperatures until the wastes are turned into ashes. Incinerators are made in such a way that they do not give off extreme amounts of heat when burning solid wastes.
• Recycling or recovery of resources is the process of taking useful but discarded items for the next use. Plastic bags, tins, glass and containers are often recycled automatically since, in many situations, they are likely to be scarce commodities.  Traditionally, these items are processed and cleaned before they are recycled.
• Recycling or recovery of resources is the process of taking useful but discarded items for the next use. Plastic bags, tins, glass and containers are often recycled automatically since, in many situations, they are likely to be scarce commodities.  Traditionally, these items are processed and cleaned before they are recycled.
• Recycling or recovery of resources is the process of taking useful but discarded items for the next use. Plastic bags, tins, glass and containers are often recycled automatically since, in many situations, they are likely to be scarce commodities.  Traditionally, these items are processed and cleaned before they are recycled.
• Composting - Due to a lack of adequate space for landfills, biodegradable yard waste is allowed to decompose in a medium designed for the purpose. Only biodegradable waste materials are used in composting.
• Composting - Due to a lack of adequate space for landfills, biodegradable yard waste is allowed to decompose in a medium designed for the purpose. Only biodegradable waste materials are used in composting.
• Composting - It is a biological process in which micro-organisms, specifically fungi and bacteria, convert degradable organic waste into substances like humus.
• Composting - It is a biological process in which micro-organisms, specifically fungi and bacteria, convert degradable organic waste into substances like humus.
• Pyrolysis - This is a method of solid waste management whereby solid wastes are chemically decomposed by heat without the presence of oxygen. It usually occurs under pressure and at temperatures of up to 430 degrees Celsius. The solid wastes are changed into gasses, solid residue of carbon and ash and small quantities of liquid. 
• Pyrolysis - This is a method of solid waste management whereby solid wastes are chemically decomposed by heat without the presence of oxygen. It usually occurs under pressure and at temperatures of up to 430 degrees Celsius. The solid wastes are changed into gasses, solid residue of carbon and ash and small quantities of liquid. 
• Climate change = All long-term changes in climate, including global warming and other effects.
• Substances that pollute bodies of water:

  • Pathogenic microorganisms
  • Putrescible organic waste
  • Plant nutrients
  • Toxic chemicals
  • Sediments
  • Heat
  • Petroleum (oil)
  • Radioactive substances
• Categories of wastes:

  • Organic waste
  • Combustibles
  • Non-combustibles
  • Toxic waste
  • Recyclables
  • Ashes or Dust
  • Construction waste
  • Hazardous waste
  • Dead animals
  • Bulky waste
  • Soiled waste
• Methods of solid waste management:

  • Sanitary Landfill
  • Incineration
  • Recovery and Recycling
  • Composting
  • Pyrolysis