Alternative Approaches to Waste (AQA A Level Geography)

Alternative Waste Disposal

• There are many ways to manage urban waste

• Ultimately, effective management is essential to reduce the environmental impact of municipal solid waste (MSW)

• The most recognisable method are the 3Rs of reduce, reuse and recycle

  • This encompasses the principle of reducing consumption of products - not using single use plastics, buying only what is needed

  • Repurposing items - using plastic carrier bags as bin liners or cola bottles as cloches to protect new seedlings 

  • Recycling items such as paper, glass etc. 

  • The benefit is that waste is reprocessed into new products which reduces demand for raw materials and decreases the environmental impact. Also, less energy is used, reducing CO2 emissions

  • However, recycling does require new infrastructure of collecting and processing facilities, which do add to greenhouse emissions and air pollution

Incineration

• Waste is burnt, which reduces the volume of waste to landfill, but the remaining ash needs to be disposed of

• Burning waste can generate electricity in a process called energy recovery

• This reduces the use of fossil fuels, but can lead to the release of toxic chemicals into the air or water

• It involves burning waste at very high temperatures, and the heat released is used to convert water to steam

• The steam is sent to a turbine generator to produce electricity

• The waste ash is collected and taken to a specialised landfill

  • But the ash can be contaminated with toxins that can leach out into the environment

• Particulates are captured by high-efficient filtering

• Energy recovery incineration is better than simple incineration because:

  • It disposes of gas, liquid and solid waste

  • It is a practical method of disposing of certain hazardous waste materials (such as biological medical waste).

  • Waste ash can be repurposed in roads and concrete (depending on type of ash)

  • Waste ash can also be reprocessed to extract recyclable metals and glass

  • High-efficiency filters remove many of the emissions

  • It reduces the amount of landfill waste 

Landfill

• Landfill is the burial of waste in hollowed out land, where it is left to decompose over time

• Waste can also be buried in disused/abandoned mines and quarries

• In the past, landfill sites were unmanaged and prevention of environmental damage minimal or non-existent

• Modern landfill sites are lined to prevent leachate from running out of the site

• Leachate is collected in pipes and transferred to special leachate ponds, where it is treated to reduce environmental damage

• Methane is produced as decomposition begins, which is either flared off or collected and used to generate electricity (gas to energy process)

• Closed landfill sites are landscaped and used as golf courses or housing etc. However, many older landfill sites are still contaminated and releasing methane into the atmosphere

• Landfill sites are 'smelly' and attract vermin and rainwater can surface wash chemicals into rivers

• In the UK, there is a general lack of space for any new landfill sites

Impact of Alternative Waste Disposal

Impacts of the Methods of Waste Disposal