CUE - Waste Flashcards
Incineration
Thermal treatment of waste (burning)
Industrialisation
The process by which an economy is transformed from primarily agricultural to one based oon manufacturing goods
Inorganic waste
Material that is non-biodegradable
Landfill
The disposal of waste material by burying it
Leachate
Toxic waste water containing contaminants leached from illegal dumps and landfill
MSW (Municipal Solid Waste)
Refuse or rubbish - composition varies between countries and changes over time
Organic waste
Material that is biodegradable
Recovery
The selective extraction of disposed materials for a specific next use
Recycling
When materials from which items are made are reprocessed into new products
Reuse
The action of using something again
Waste stream
The complete flow of waste from its source through to disposal, recovery or recycling
Globally waste increases by —% per year
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What are the 3 primary sources of waste in urban areas?
Industrial waste - produced by manufacturing processes or from industrial activity
Commercial waste - waste produced by businesses
Personal waste - waste produced in private homes
How do waste streams and components of waste depend on economic characteristics?
As people become richer, they tend to consume more goods
Most developing countries do not have formal recycling systems but many people collect recyclable goods from landfill and sell them to make a living
How do waste streams and components of waste depend on lifestyles?
People in urban areas generally produce more waste than in rural areas. Urban areas produce more manufactured waste while rural areas produce more organic waste
Diet impacts this as well as processed food produces more packaging than fruit and vegetables
How do waste streams and components of waste depend on attitudes?
Many developed countries have a ‘throw-away culture’ with electronics replaced regularly and clothing thrown away after a few wears resulting in high levels of waste
In some groups there is a movement towards decreasing consumption and waste e.g freegans forage for food, repair broken goods and give away things tthey dont need
What are the impacts of increasing waste generation?
Cities are running out of landfill space
Water, ground and air pollution
Costs of collecting and treating waste is high
What is unregulated waste disposal?
When waste is dumped in places that arent official disposal sites e.g solid waste left on the street
This can result in:
Waste damaging ecosystems
Contamination of groundwater or surface water by leachate
Waste becoming a breeding ground for insects, vermain and animals so the spread of disease occurs
What is recycling as a method of waste disposal?
Where waste is reprocessed into new products
This means that less waste is disposed of and the demand for raw materials is reduced (using less energy and less production of greenhouse gases)
What is incineration as a method of waste disposal?
When waste is burned —> releasing greenhouse gases into the atmopshere by combustion
This does reduce the amount of waste being sent to landfill (reducing the volume of waste by 90%). Energy recovery can also take place with electricity being generated
What is landfill as a method of waste disposal?
Waste is placed in disused mines, quarries or landfill sites and buried there (in lower income counttries they may use a hole in the ground)
In HICs, the regulations of waste disposal is much stricter with landfill sites lined with clay or plastic to prevent leaching of chemicals into the environment
In some countries e.g the UK the methane is collected for energy production - reducing the demand for fossil fuels and therefore the removal of the slow carbon lithospheric store
Issues of landfill ae:
Methane is produced by decomposition
Toxic chemicals can leach out and contaminate groundwater
What is submergance as a waste disposal waste?
Disposing of waste by dumping it into oceans (illegal method but is common in some areas)
Submerged wastte can release toxic or radioactive substances, damaging ocean ecosystems
What is trade as a waste disposal method?
Waste may be moved between countries - the global waste trade is the international trade of waste between countries for further treatment, disposal or recycling
HICs may pay LICs or NEEs to take their hazardous waste as they do not want to deal with it
There are less strict regulations of waste disposal in LICs and NEEs so the production of leachate and toxic gases can lead to ecosystem damage and health issues there
What are the advantages and disadvantages of incineration as a waste disposal method?
Advantages:
- Can reduce waste volume by up to 90%
- Energy recovery can occur by burning waste generating electricity —> reducing the use of fossil fuels
Disadvantages:
- Combustion is a fast flow of greenhouse gases containing carbon into the atmosphere
- Open burning that occurs in poorer countries causes air pollution
- Incinerator bottom ash left over needs to be disposed of
- Expensive to build sites
What are the advantages and disadvantages of using landfill as a waste disposal method?
Advantages:
- Energy recovery can occur with the methane released from the decomposition of waste being used as an energy source —> reducing the disruption of slow lithospheric carbon stores
- Revegetation of sealed waste disposal spaces can remove carbon from the atmosphere through photosynthesis and create recreational spaces
Disadvantages:
- If not sealed correctly, potential leaching of chemical can contaminate nearby soil and water supplies
- Decomposition of waste produces methane as a fast flow of carbon to the atmosphere (slower than the release of carbon by incineration) it is also an explosive gas
- May run out of space
- High transportation costs
Give some background information about Singapore
Small island nation in south-east Asia
Densely populated with 100% of people living in the urban area with a growing population so diminishing space
In 1965, Singapore gained independence from Malaysia so experienced strong economic growth and social stability
What is waste like in Singapore?
Between 1970 and 2000, waste production in Singapore has increased by over 6x
The state is running out of space rapidly so has shifted from landfill to incineration
The current approach is to avoid making waste in the first place with a public campaign by the government towards the three Rs
Cash-for-trash schemes encourage citizens to recycle with 60% of people in Singapore now recycling their waste
Energy is also generated by incinerating residual waste and dumping what is left in an environmentally acceptable way
How has waste in Singapore changed over time (1960/70s to 2000s)
1960s/70s
Most waste sent to landfill
Environmental degradation and lack of physical space forced government to take action
1970s
Late 70s Singapore government changed waste disposal strategy from landfill to incineration with energy recovery
First incineration plant constructed in 1979
2000s
Singapore begins to use one landfill site called Semakau which was built on reclaimed land offshore from the island
It is expected to be filled by 2040
What is waste disposal like in Singapore today?
There are 4 incineration plants around the city that provide 3% of the city’s energy needs
Singapore produced 52.5 million tonnes of carbon dioxide in 2017
each person creates 2lb of waste per day
Give the successes and limitations of waste disposal in Singapore
Successes
Heat produced during he incineration process is converted into electricity with 1,600 MWh of electricity produced every day
Last year 58% of waste of recycled and 2% was sent to landfill
The incinerators are fitted with pollution control systems to reduce the emission of greenhouse gases - they can reduce up to 90% of harmful nitrous oxides released
Limitations
Semakau is expected to be filled by 2040 so Singapore will have to find an alternative location for landfill
Although energy is being generated a lot of emissions are still being created with 52.5 million tonne of carbon dioxide released in 2017
Incinerators need to be replaced every 10 years so new plants will need to be built soon
