Chapter 5 - Materials and Waste Flashcards
Comment on the resource consumptions trends for metals, steel and wood.
Metals - exponential growth in consumption leading to lower quality ores being used.
Steel - Reduced rate of growth due to recycling but still growing.
Wood - continuous growth leading to deforestation.
What materials does the UK consume the most and which have the highest environmental impact?
We consume aggregates and concrete products the most.
Aggregates have the most significant environmental impact/opportunity for change despite it being a very recycled resource.
What are some of the hidden impacts of material use?
Transportation of materials, using land to obtain the materials, energy/water to process materials, waste disposal etc.
What are some of the positive and negative impacts of the construction industry?
Positive - Infrastructure, jobs, restoration of historic buildings.
Negatives - land use, traffic, noise pollutions.
How does the UK rank amongst Europe in terms of recycling materials?
We are the best (GOD SAVE THE QUEEN). We have the highest recycled and secondary materials in Europe.
Give examples of technical barriers that prevent recycling.
Design specification - they give limited guidance/standards on the quality of recycled materials.
Knowledge & experience - when people don’t know how to use or source recycled materials.
Give examples of non-technical barriers that prevent recycling.
Planning permission & investment - to build infrastructure associated with recycling.
Supply - the availability and location of recycling facilities.
What standards exist about recycled materials and which are being made?
British standard has guidance about requirements for recycled aggregates and crushed concrete aggregates but nothing other than this.
Standards being made about the processing of recycled aggregates.
What is the waste hierarchy (preferred methods of dealing with used materials) from best to worst?
- Prevention - reduce the generation of waste.
- Re-use - for the same or different purpose.
- Recycle - recover resources from the waste.
- Recovery - use the waste for non-material purposes like burning for fuel.
- Disposal
How have waste policies changed to encourage recycling?
They now include plans for re-use and recycling as well as the need to monitor and report levels or recycling and re-use at these sites.
What is a site waste management plan?
a ‘living’ plan that details the amount and type of waste estimated and actually produced on a construction site and a plan for how it will be reused, recycled or disposed of.
Why are site waste management plans used?
To prevent illegal waste dumping, to handle it in a responsible way and improve material resource efficiency.
What is a linear economy model?
An economic model where virgin materials are taken from nature, used to make products which are consumed and then disposed of.
What is a circular economy model?
An economic model that aims to decouple economic growth and development from the consumption of finite resources. It aims to keep products and components useful and high value for as logn as possible.
What are some of the challenges for engineers regarding reuse and recycling?
Lack of knowledge and information. Designing for disassembly and refurbishment. Storage spaces for the material while awaiting processing. Quality control.
