8.3 Solid Domestic Waste

The Big Picture

• Waste is diverse and increasing in volume as we gain more stuff and as the population grows

• Domestic waste = household waste 

• Increase in e-waste

• Increase in recycling efforts and composting 

• Waste needs to be managed

Solid Domestic Waste (SDW) (trash)

• Industry & urbanization increased the amount of SDW due to:

  • Increase in waste creation → more ppl buy more stuff

  • Decrease in quality of life in cities → due to more trash

  • Increase in waste led to unsanitary conditions & disease outbreaks (like cholera)

Case Study: London

• 1846- Nuisance Removal & Disease Prevention Act (initial regulation of waste management)

• 1874- first incinerators

• 1875- Public Health Act (waste bins & waste collection by open trucks)

  • open trucks = problem bc waste can fall out

• 1920s- closed trucks for collection

• 1938- modern hydraulic compactors 

• As waste increased, management of it improved 

Types of SDW

• Organic material (food waste, clothing)

• Paper, plastic, metal, glass (medical waste, batteries, e-waste, paint, household chemicals, etc.)

• Hazardous waste

• Other waste (ceramic, rock, ash, soil)

Linear v.s. Circular Economies

Linear

Make smth → use it → dispose of it → wasteful + damaging

Circular

Goods are designed to reenter the system naturally, be recycled, or used again. 

Restorative.

• Biological nutrients (compost)

• Technical nutrients (recycling e-waste)

Bad SDW

Non-biodegradable waste 

• Doesn’t break down

• Plastic: made from crude oil

Toxic Waste

• Batteries & e-waste

• E-waste can be recycled to an extent

Landfills

• Must be lined to avoid leaching 

• Smaller is more easily monitored

• Waste must be compacted to reduce volume

• Needs to be covered to reduce smell, vermin, litter dispersal

• Dumps have a lifespan

  • Dependent on: compressibility of waste, thickness of the layers, frequency of compaction, amount added each day

Advantages

• mass disposal (easy)

• lower cost

• create jobs

Disadvantages

• can negatively affect communities

• methane creation

• takes up space

• limited storage/life

Waste to Energy

• Landfills create methane when waste breaks down

• Methane is often burned off through flares → creates more pollution

• Methane can be captured (thru wells) and used to generate electricity (advantage)

Incineration

• Burns waste 

• Creates ash, flue gas (which contains PM + pollutants), and heat

• Electricity can be generated from the heat 

• Helpful when space for landfills is limited 

• Advantages and disadvantages?

Adv.

• less space than landfills

• create jobs

• can create energy

• may last longer than a landfill

Disadv

• to build them

• create pollution (scrubbers to reduce)
  need to dispose of ash

Recycling

The 3 Rs

1. Reduce

2. Reuse

3. Recycle

Design Phase

• less use of raw materials → less waste

• lower energy consumption

Reuse, repurpose, donate

Transform original product into something new

Recycling is far from perfect

Need infrastructure to process materials

Indefinite recyclability: glass, metals

Limited recyclability: paper/cardboard (5-7 times)

Nor really recyclable: plastic (only 1-2 times)

Composting

• Food waste can generate a lot of methane in landfills

• Composting keeps the food waste out of landfills

• When composting, need to control amounts of C & N, monitor moisture, control pests, ensure heat to speed up breakdown process 

• Combines the 3 R’s

• Aerobic decomposition (uses O2 — does not release CH4)

Dealing with Pollution

• All of the strategies discussed are for managing pollution

• The strategy used depends on the localities culture, economic status, available technology, and the local politics

• Educate (cheap) → Legislate (laws about…) → Remediate (most costly: clean up the mess)

• educate abt how to separate trash

  • ex: rinse ur recyclables, sustainable purchasing, how to compost

The Circular Economy Model

• Ellen MacArthur (see page 10) sailed around the world and likened Earth to a boat

• Linear economy: take → make → use → dispose

• Circular economy: take, make, use → reuse, repair, remake, remove waste, regenerate natural resources

3 Principles

1. Eliminate waste & pollution 

   1. Linear economy is wasteful; resources are finite

   2. Product design allows for resources to re-enter the economy 

2. Circulate products & materials 

   1. Technical cycle: maintain/ reuse entire products (they can have a life after you’re done with it) 

   2. Biological cycle: food by-products can be composted or anaerobically digested; use waste to replenish soil to grow more food

3. Regenerate nature

   1. Shift focus from extraction to regeneration 

      1. Regenerative agriculture: crop growth to enhance soil health, ranching in harmony with grasslands

Uses of circular economy model (strengths)

• Regenerate natural systems 

• Reduce GHG emissions

• Improve local food networks/ support local communities

• Extend life of products to reduce waste

• (Educate) consumers to change habits 

Limitations of circular econ. model

• Lack of environmental awareness by consumers & companies

• Lack of political will to push education of circular use

• Lack of regulations for recycling of products 

• Not all waste is recyclable/ reusable

• Lack of finances to support recycling of goods

• Push edu of circular use