Waste management

• Approaches to waste management:

  • The 3 R's ~ Reduce Reuse Recycle
• Steps of waste management:

  1. Reduce waste
  2. Reuse waste
  3. Recycle, if not possible then compost organic waste, if not possible then incineration and energy recovery
  4. Landfill
• The waste hierarchy:


  This consists of waste diversion which is:

  • Reduce
  • Reuse
  • Recycle

  And also waste disposal which is:

  • Energy recovery - incineration to produce electricity
  • Disposal - landfill

  This makes up the circular economy

  A) Waste diversion

  B) Waste disposal

  
• Environmental impacts of alternative approaches to waste disposal

  • In HICS - waste disposal typically landfill and incineration (with energy recovery)
  • In LICS - waste disposed of in open dumps and unreguated dumping > increase methane pollution > climate crisis
• Recycling:


  • Become very valuable global market > combined value of scrap metal and paper/ cardboard recycling annually is at least $30 billion.
  • In HICS recycling occurs via collected bins and sometime often monetary incentives
  • In LICS no systems or collected by hand and sold > informal economy
• Urban mining


  • The process of recovering compounds and elements from products, buildings and waste which otherwise would decompose in landfill.
  • Collection and salvage of valuable components to be recycled or reused reduced impact on landfill
  • E.g. producing aluminium from recycled aluminium used 95% less energy
• EXAMPLE: Urban mining in Nigeria, Lagos:


  • Releases toxic chemicals > pollution > kills fish in water > leaching > pollutes ground water > contaminates water supply > bioaccumulation > health impacts
  • Only handful of government facilities for recycling
  • Burn waste instead > plastic > toxic fumes > pollution
  • Refurbished technology > high demand for materials > Nigeria producing own e-waste > more waste
• The global waste trade

  • Waste transported within countries and between countries. Much toxic and hazardous waste often transported from HICS to LICS and NEES
  • Env consequence of this is dangerous waste to handle and trade e.g. nuclear and large carbon footprint of transportation
• EXAMPLE: E-waste in Guiyu, S China - World's largest dumping site for e-waste ~ how significant was the problem of e-waste + impacts?


  • Waste disposal on every street
  • Waste arrives by truckload
  • Metal picking to earn money (100,000) people

  Impacts:

  • Water & air pollution > contain mercury
  • Into food supply > bioaccumulates > farmers don't eat own crops
  • Dangerous
  • Contaminated soil
  • Decrease biodiversity > LT impact
• EXAMPLE: E-waste in Guiyu, S China - World's largest dumping site for e-waste ~ how it's been tackled:


  • Gov crackdown on burning plastic
  • Banned importing electronic waste
  • $233 million invested in industrial parks
  • Industrial park > air purification system and waste sewage water
  • Decreased income but better air quality
  • 2013 set up gov park to bring in 1200 former domestic workshops into 29 specific controlled workshops
  • Environment primary focus, profit secondary
• Incineration of waste:

  • In HICs ~ incineration reduces volume of disposed waste by up to 90%, in HICs, it occurs in form of controlled facilities e.g. controlled fires and then capture energy
  • In LICs ~ involves open uncontrolled burning > release toxic gases and fumes, no facilities with continuous fires that do not go out
• What is incineration?


  • Waste is burned but remaining ash needs to be disposed of
  • Burning can generate elec = energy recovery
  • Reduces use of fossil fuels but leads to toxic chemicals in air and water
  • Burn waste at high temp and heat released to convert water to steam
  • Steam sent to turbine generator to produce elec
  • Waste ash collected and taken to specialised landfill but ash may be contaminated which leach into env
  • Particulates captured by high-efficient filtering
• EU targets:


  • Recycle 65% of municipal waste by 2030
  • Recycle 75% of packaging waste by 2030
  • Reduce landfill to max 10% of municipal waste by 2030
• How does landfill work?

  1. Seal the base with clay and geomembrane > impermeable to stop leachate infiltrating into groundwater e.g. Bentonite
  2. Pipes redirect leachate and drain it, or transferred to leachate ponds to treat it and decrease env impact
  3. Layer and compact rubbish
  4. Methane produced as decomposition begins > either flarred off (burnt before entering atmosphere) or collected and used for energy recovery
  5. Closed landfill sites seal with clay
  6. Landscape and repurpose for industry or commercial e.g. golf course, housing
• EXAMPLE: Incineration - AEB Incineration Plant, Amsterdam:

  • Waste-to-energy (W2E) AEB incineration plant > produce 1mill MWH of elec/year
  • Plant also used to create heating > 300,000 gigajoules/yr > decrease energy cost
  • 1.4 mill tonnes of waste/yr brought to W2E, 64% of waste recycled
  • AEB plant installed processes of scrubbing flue gasses > avoids 438 kiloton of CO2 per year
• EXAMPLE: Incineration - AEB Incineration Plant, Amsterdam 2:


  • Next door Waternet water treatment plan > incineration plant provides energy and heat for water treatment and this plant injects sludge and biogas into incineration as another fuel source > synergy
  • If same amount of waste was in landfill the CO2 would be over 1000 kilotons
• Landfill advantages:


  • Facilities properly sites with necessary controls
  • Different waste types accepted
  • Can be repurposed
• Landfill disadvantages:


  • Unsightly
  • Attract vermin - disease
  • Lack of space
  • Potential leaching of chemicals threatens groundwater supply
  • Decomposing matter produces methane
  • Opposed by neighbouring residents
  • High transportation costs
• Incineration advantages:


  • Decrease volume of waste needed for disposal by 90%
  • Inactivate disease
  • Decrease toxicity of waste
  • Produce energy
  • Incinerator bottom ash recycled as secondary aggregate
• Incineration disadvantages:


  • Expensive
  • Not all waste combustible
  • Air pollution and incinerator bottom ash disposal
  • Capacity limitations
  • Unpopular with local residents
• EXAMPLE: London urban waste:

  • 61% recycled
  • 24% landfill
  • 8% other
  • 6% incineration
• EXAMPLE: London urban waste:
Why did most of the urban waste go to landfill


  • Space available historically before urban sprawl
  • Out of sight before major tourism and business districts
  • Along major transport routes

  Why is this no longer the case?

  • Increase 3Rs
  • Increase incineration
  • Increase env conscious
  • Residential development
• EXAMPLE: London urban waste - what is ReLondon?

  • A partnership of the Mayor of London and London's boroughs to increase waste/ resource management and accelerates transition into a low carbon circular economy
  • Decrease waste and increase 3Rs = global leader in sustainable living
• EXAMPLE: London urban waste - what is the circular economy?


  • One in which stuff is kept in use for as long as possible, delivering highest value it can, for as long as it can through reusing materials and products in many different forms
• EXAMPLE: London urban waste - the scale of the waste problem

  • 7m tonnes of waste produced/ yr - 3m from households
  • More than 1/4 household waste is food
  • 10% more packaging, 5% nappies/ sanitary products
• EXAMPLE: London urban waste - recycling rates, targets and examples of key challenges:


  Rates:

  • Current household recycling rates = 33%
  • Non-household similar

  Target:

  • 65% recycled by 2030
  • Get household recycling to 50% and non-household to 75

  Challenges:

  • Highly transient population (not lasting) > decrease home ownership and increase rented, ST housing
  • Increasing percentage of flats > challenges to residents and council collection teams
  • Daytime visitors (1 mill daily commuters) = extra waste
• EXAMPLE: London urban waste - energy recovery from incineration ~ SELCHP:


  • SELCHP = South East London Combined Heat and Power
  • It is an energy recovery facility that takes waste that can't be recycled and turns it into energy which is sold to National Grid
  • Capable of handling 420,000 tonnes of waste/yr
  • Produces enough elec to power approx 48,000 local homes