Sustainability / Separations / Recycling

What are the stages of the waste hierarchy?

1. Reduce

2. Reuse

3. Recycling

4. Recovery

5. Disposal

Explain ‘reduce’ in the Waste Hierarchy and give an example

• Prevention of waste at source

• E.g. efficient use of raw materials, purchase items with less packaging, increase process efficiency

Explain ‘reuse’ in the Waste Hierarchy and give an example

• Any operation by which waste or its components are used for the same purpose for which they were conceived

• Including the continued use of equipment or components which are returned to collection points, distributors, recyclers or manufacturers

• E.g. reuse packaging, use both sides of paper, reuse containers, send containers back for refilling

Explain ‘recycling’ in the Waste Hierarchy and give an example

• Any reprocessing of material in a production process that diverts it from the waste stream, except reuse as fuel.

• Both reprocessing as the same type of product, and for different purposes

• E.g. segregation of wastes for processing, paper to newsprint, cars to new steel

Explain ‘recovery’ in the Waste Hierarchy and give an example

• Any waste management operation that diverts a waste material from the waste stream making product with a potential economic or ecological benefit

• E.g. municipal waste incineration with energy recovery

Explain ‘disposal’ in the Waste Hierarchy and give an example

• Any waste management operation carrying out the final treatment and disposal of waste

• E.g. deposit into or onto land (e.g. landfill), deep injection, surface impoundment release into water bodies, permanent storage

Identify four potential risks in terms of contaminants and source, pathway and receptor relationships

Describe linear economy

• Take, make, use, dispose

• Technical and biological materials mixed up

• Energy from finite sources

Describe circular economy

• Cycling of materials

• Technical and biological materials in separate cycles

• Energy from renewable sources

What are the main drivers for sustainable resource use?

• declining reserves

• increasing demand

• security / location of supply

How is waste defined?

Any substance or object which the holder discards or intends or is required to discard

What is the material balance for a binary separator?

What are the equations involved for the material balance for the binary separator?

Describe the principle of operation of three physical separation processes that can be used to separate different fractions of the MSW