ch6: solid waste

Question 1

What is waste?

Answer 1

• In biology, waste is any of the many unwanted substances or toxins that are expelled from living organisms, metabolic waste;
• Such as urea and sweat.
• Waste is unwanted or useless materials.
• also known as:
  
  • rubbish,
  • trash,
  • refuse,
  • garbage,
  • junk,
  • litter, and
  • ort

Question 2

Basel Convention Definition of Wastes

Answer 2

• substances or objects which are disposed of or are intended to be disposed of or are required to be disposed of by the provisions of the law

Question 3

Disposal means

Answer 3

• any operation which may lead to resource recovery, recycling, reclamation, direct re-use or alternative uses (Annex IVB of the Basel convention)

Question 4

Define solid waste:

Answer 4

• Solid wastes: wastes in solid forms, domestic, commercial and industrial wastes
• Examples: plastics, styrofoam containers, bottles, cans, papers, scrap iron, and other trash

Question 5

Define liquid wastes:

Answer 5

• Liquid Wastes: wastes in liquid form
• Examples: domestic washings, chemicals, oils, waste water from ponds, manufacturing industries and other sources

Question 6

According to EPA regulations, SOLID WASTE is

Answer 6

• Any garbage or refuse (Municipal Solid Waste)
• Sludge from a wastewater treatment plant, water supply treatment plant, or air pollution control facility
• Other discarded material
• Solid, semi-solid, or contained gaseous material from industrial, commercial, mining, and agricultural operations, and from community activities

Question 7

Classification of Wastes according to their Properties

Answer 7

• Bio-degradable:
  
  • can be degraded (paper, wood, fruits and others)
• Non-biodegradable:
  
  • cannot be degraded (plastics, bottles, old machines,cans, styrofoam containers and others)

Question 8

Classification of Wastes according to their Effects on Human Health and the Environment

Answer 8

• Hazardous wastes:
  
  • Substances unsafe to use commercially, industrially, agriculturally, or economically and have any of the following properties- ignitability, corrosivity, reactivity & toxicity.
• Non-hazardous :
  
  • Substances safe to use commercially, industrially, agriculturally, or economically and do not have any of those properties mentioned above. These substances usually create disposal problems.

Question 9

Classification of wastes according to their origin and type

Answer 9

• Municipal Solid wastes
• Bio-medical wastes
• Industrial wastes
• Agricultural wastes
• Fishery wastes
• Radioactive wastes
• E-wastes

Question 10

Define Municipal solid waste:

Answer 10

• Solid wastes that include household garbage, rubbish, construction & demolition debris, sanitation residues, packaging materials, trade refuges etc. are managed by any municipality.

Question 11

Define Bio-medical wastes:

Answer 11

• Solid or liquid wastes including containers, intermediate or end products generated during diagnosis, treatment & research activities of medical sciences.

Question 12

Define industrial wastes:

Answer 12

• Liquid and solid wastes that are generated by manufacturing & processing units of various industries like chemical, petroleum, coal, metal gas, sanitary & paper etc.

Question 13

Define agricultural wastes:

Answer 13

• Wastes generated from farming activities. These substances are mostly biodegradable

Question 14

Define fishery wastes:

Answer 14

• Wastes generated due to fishery activities. These are extensively found in coastal & estuarine areas.

Question 15

Define radioactive wastes:

Answer 15

• Waste containing radioactive materials. Usually these are byproducts of nuclear processes. Sometimes industries that are not directly involved in nuclear activities, may also produce some radioactive wastes, e.g. radio-isotopes, chemical sludge etc.

Question 16

Define E-wastes:

Answer 16

• Electronic wastes generated from any modern establishments. They may be described as discarded electrical or electronic devices. Some electronic scrap components, such as CRTs, may contain contaminants such as Pb, Cd, Be or brominated flame retardants.

Question 17

Sources of wastes:

Answer 17

• Households
• Commerce and industry

Question 18

Impacts of waste if not managed wisely:

Answer 18

• Affects our health
• Affects our socio-economic conditions
• Affects our coastal and marine environment
• Affects our climate
• GHGs are accumulating in Earth’s atmosphere as a result of human activities, causing global mean surface air temperature and subsurface ocean temperature to rise.
• Rising global temperatures are expected to raise sea levels and change precipitation and other local climate conditions.
• Changing regional climates could alter forests, crop yields, and water supplies.
• This could also affect human health, animals, and many types of ecosystems.
• Deserts might expand into existing rangelands, and features of some of our national parks might be permanently altered.
• Some countries are expected to become warmer, although sulfates might limit warming in some areas.
• Scientists are unable to determine which parts of those countries will become wetter or drier, but there is likely to be an overall trend toward increased precipitation and evaporation, more intense rainstorms, and drier soils.
• Whether rainfall increases or decreases cannot be reliably projected for specific areas.

Question 19

Activities that have altered the chemical composition of the atmosphere:

Answer 19

• Buildup of GHGs primarily carbon dioxide (CO2) methane (CH4), and nitrous oxide (N20).
• C02 is released to the atmosphere by the burning of fossil fuels, wood and wood products, and solid waste.
• CH4 is emitted from the decomposition of organic wastes in landfills, the raising of livestock, and the production and transport of coal, natural gas, and oil.
• N02 is emitted during agricultural and industrial activities, as well as during combustion of solid waste and fossil fuels. In 1977, the US emitted about one-fifth of total global GHGs.

Question 20

Exposures occur through:

Answer 20

• Ingestion of contaminated water or food
• Contact with disease vectors
• Inhalation
• Dermal

Question 21

Points of contact:

Answer 21

• Soil adsorption, storage and biodegrading
• Plant uptake
• Ventilation
• Runoff
• Leaching
• Insects, birds, rats, flies and animals
• Direct dumping of untreated waste in seas, rivers and lakes results in the plants and animals that feed on it

Question 22

Categories of waste disposal

Answer 22

• Dilute and disperse (attenuation) then through it in the river/ lake/ sea or burn it
  
  • Basically this involves spreading trash thinly over a large area to minimize its impact
  • Works for sewage, some waste chemicals, when land disposal is not available
  • Examples: plastic in pacific
• Concentrate and contain (isolation) then waste dumps, landfills
  
  • Historically, that’s how most of the solid waste gets treated

Question 23

The Advantages and Disadvantages of Burning or Burying Solid Waste

Answer 23

• Technologies for burning and burying solid wastes are well developed
  
  • However, burning contributes to air and water pollution and greenhouse gas emissions, and buried wastes eventually contribute to the pollution and degradation of land and water resources

Question 24

Burning Solid Waste Has Advantages and Disadvantages

Answer 24

• Waste-to-energy incinerators
  
  • To heat water or produce electricity
• Landfills emit more air pollutants than modern waste-to-energy incinerators
  
  • Toxic chemicals that are filtered must be disposed of or stored

Question 25

**Waste to energy incineration trade off:**

Answer 25

Question 26

**Burying Solid Waste Has Advantages and Disadvantages**

Answer 26

* Sanitary landfills * Compacted layers of waste between clay or foam * Bottom liners; containment systems * Open dumps * Widely used in less-developed countries * Rare in developed countries * Large pit * Sometimes garbage is burned

Question 27

**Sanitary Landfills tradeoff:**

Answer 27

Question 28

**Waste hierarchy**

Answer 28

* Waste hierarchy refers to 3 Rs Reduce, Reuse, Recycle * From most favoured option to least favoured option: * Prevention * Minimization * Reuse * Recycling * Energy recovery * Disposal

Question 29

**How to minimize solid waste:**

Answer 29

* Minimizing packaging * Recycleable * Paper, plastics, metals, glass, wood * Reusable ? * Textiles, leather, rubber, metals, wood * Compostable * Yard trimmings, food scraps (vegetable)

Question 30

**Primary, closed-loop recycling**

Answer 30

* Materials recycled into same type

Question 31

**Secondary recycling:**

Answer 31

* Materials converted to other products: tires

Question 32

**Types of wastes that can be recycled**

Answer 32

* Preconsumer, internal waste generated in manufacturing process * Postconsumer, external waste generated by product use

Question 33

**Recycling Paper**

Answer 33

* Production of paper versus recycled paper * Energy use – world’s fifth largest consumer * Water use * Pollution * Easy to recycle * Uses 64% less energy * Produces 35% less water pollution * Produces 74% less air pollution

Question 34

**Recycling Plastics**

Answer 34

* Plastics * Composed of resins created from oil and natural gas * Currently only 7% is recycled in the U.S. * Many types of plastic resins * Difficult to separate

Question 35

**Recycling Has Advantages and Disadvantages**

Answer 35

* Advantages * Net economic health * Environmental benefits * Disadvantages * Costly * Single-pickup system * No separation needed

Question 36

**Recycling trade off:**

Answer 36

Question 37

**Effects of waste on animals and aquatics life:**

Answer 37

* Increase in mercury level in fish due to disposal of mercury in the rivers. * Plastic found in oceans ingested by birds. * Resulted in high algal population in rivers and sea. * Degrades water and soil quality.

Question 38

**Impacts of waste on Environment**

Answer 38

* Waste breaks down in landfills to form methane, a potent greenhouse gas * Change in climate and destruction of ozone layer due to waste biodegradable * Littering, due to waste pollutions, illegal dumping, Leaching: is a process by which solid waste enter soil and ground water and contaminating them.

Question 39

**What should be done**

Answer 39

* Reduce Waste * Reduce office paper waste by implementing a formal policy to duplex all draft reports and by making training manuals and personnel information available electronically. * Improve product design to use less materials. * Redesign packaging to eliminate excess material while maintaining strength. * Work with customers to design and implement a packaging return program. * Switch to reusable transport containers. * Purchase products in bulk. * Reuse * Reuse corrugated moving boxes internally. * Reuse office furniture and supplies, such as interoffice envelopes, file folders, and paper. * Use durable towels, tablecloths, napkins, dishes, cups, and glasses. * Use incoming packaging materials for outgoing shipments. * Encourage employees to reuse office materials rather than purchase new ones. * Donate/ exchange * old books * old clothes * old computers * excess building materials * old equipment to local organizations

Question 40

Residents may be organized into small groups to carry out the following:

Answer 40

* construction of backyard compost pit * construction of storage bins where recyclable and reusable materials are stored by each household * construction of storage centers where recyclable and reusable materials collected by the street sweepers are stored prior to selling to junk dealers * maintenance of cleanliness in yards and streets * greening of their respective areas * encouraging others to join