Urban waste

Question 1

What is municipal solid waste

Answer 1

MSW
-2002 2.9 billion residents generated 0.64 kg
-2012 3 billion generated 1.2 kg
-2025 expected 4.3 billion generating 1.42 kg per day

Question 2

What are the sources of waste in urban areas ?

Answer 2

-Residential
-Industrial
-Commercial
-Institutional
-Construction
-Urban services

Question 3

What are the impacts of increasing waste generation ?

Answer 3

-Costs of collecting and treating waste is high (20-50% of urban authorities budget is spent on solid waste management)
-Waste is a large source of methane
-Untreated/uncollected waste can cause health issues
-Many authorities are struggling to collect increasing quantities of waste
-Cities are running out of landfill space

Question 4

Methods of waste management and disposal

Answer 4

Recycling and recovery
-Resource recovery is the selective extraction of disposed materials for a specific next use like composting or energy generation
-Recycling is carried out when materials from which the items are made can be reprocessed into new products
-Energy may be required, greenhouse gases produced
-Reduced quantities of disposed waste and return of materials to economy
Trade
-Global waste trade is the international trade of waste between countries for further treatment, disposal or recycling.
-Countries often don’t have safe recycling processes or facilities leading to contamination
Incineration
-Can reduce the volume of waste by up to 90%
-General waste can be safely burned at high temperatures and under controlled conditions produce heat and electric (waste to energy)
-High costs, pollution
Landfill
-The placement of waste in man-made or natural excavations, like pits or landfills
-Common final disposal site for waste from urban areas. LIC may be open dumping.
-In the UK most landfill sites now control and collect the gas that is released by the decomposing waste, often using it to generate electricity through turbines
-Greenhouse gases produced by rotting organic matter