Urban waste

Question 1

Whats the definition of waste?

Answer 1

Waste is any unwanted and any unusable material.

• Global waste increasing due to population growth and increasing development, this also includes electrical use as people throw away old products as technology improves.

Question 2

What is the definition of municipal solid waste?

Answer 2

Refuse or rubbish produced and generated by households.

Question 3

What is the definition of recycling?

Answer 3

The process of breaking down old products and making new ones out of them.

Question 4

Southwark, London (Urban waste disposal case study):

Answer 4

Waste stream for recyclables:

• Residents put recyclables in blue bin.
• Collected kerbside and go to tipping hall at material recovery factory.
• Goes along belt, cardboard taken out it then enters tunnels and material separated.

Waste streams for incineration:

• Collected kerbside from green bin and waste sorted by machine which separates mixed waste and recyclables.
• Moisture removed and made into fuel blocks, sent to energy recovery factory and burnt.
• Acidic gas which is released is neutralised + removed

Progress to goal:
- Aim to recycle 50%, currently recycling 34%.

Reuse schemes:

• Community repaint schemes which saved 8.5 tonnes of paint
• Recycling bikes saved 1.86 tonnes
• Furniture etc collected and sold at British Heart foundation shops, made them £35,000.

Question 5

Advantages and disadvantages of the processes used in Southwark:

Answer 5

Landfill:

• Cheap solution which is easily managed
• Sealed once full and safe if well managed
• Methane produced can be used as fuel
• Attracts vermin due to smells
• Produces methane
• Toxins can leak into soil and water.

Recycling:

• Reduces landfill
• New products without using new materials, more sustainable approach
• Generates noise and litter
• If up to public separate materials its prone to error

Incineration:

• Long lasting and cost effective
• Doesn’t take up valuable space
• Safe disposal for hazardous waste
• Not all waste is combustable
• CO2 emissions and particular matter is produced.

Question 6

What do waste streams depend on?

Answer 6

1. Economic character:
   - As people get wealthier they consume more and developed countries produce more waste (2.1kg per day per person, 0.6kg in developing)
   - Components of the waste is also different in developed compared to developing, main component in developed is paper (31%) while in developing its organic matter (64%)
2. Lifestyles:
   - Amount of waste and type is dependant on whether people live in cities (more and commonly manufactured waste) or in rural areas (less and commonly organic waste)
   - More likely to recycle if the facilities are available to them and if they are encouraged by governments.
3. Attitudes:
   - Many devolving countries have a throw away culture and replace clothes and electronics, results in high complex waste.
   - High levels of food waste due to culture of best before dates etc.

Question 7

Mumbai case study (urban waste):

Answer 7

Mumbai produces 11,000 cubic metric metres tonnes of rubbish each day. They currently have no official refuge collection system.

• All waste is taken to landfill and an informal system of rag pickers collect all waste which can be recycled. This results in 80% of all of the cities waste being recycled.

Issues:

• Massive Impact upon ragpicker health due to the toxic waste that is released as well as needles etc leading to the spread of disease. Not socially sustainable.
• Many children also forced to become ragpickers so issues with child labour.
• Many landfill sites are still overflowing even with ragpickers.