Recycling ferrous metals, such as scrap iron and steel, can save up to 75 percent of the energy needed to make products from raw materials.
Ferrous metals are metals that contain iron, including wrought iron, cast iron, steel and stainless steel. Common sources include old cars, household appliances, steel beams, railroad tracks, ships, food tins, bottle tops, paint cans and aerosols.
Recycling ferrous metals has many financial and environmental benefits. It diverts them from landfill, reduces the need to extract and manufacture raw materials and contributes to significant savings in greenhouse gas emissions. Recycling steel, for example, uses 75% less energy than making steel from raw materials. All types of steel are 100% recyclable and can be recycled an infinite amount of times.
South Australians recycled 282 thousand tonnes of commercial steel in 2006-071. That's the equivalent "everyday" savings of around 1.2 million household's energy use for a month.
"Everyday" and unit savings per tonne of steel2 recycled:
|2,130 km driven3|
|0.4 tonnes CO2e|
|4.4 houses' energy for a month4|
|7.94 GJ LHV (2,207kWh)|
|-13 bath tubs5|
|-2.36 kL water|
|18 wheelie bins6|
For an explanation of key terms used, please visit our Glossary.
There are many scrap metal companies who offer a combination of drop-off, pick-up and on-site collection bin services for ferrous scrap. Some companies offer payment for your scrap and some may offer free pick-up and/or drop-off. Some on-site bin and collection services may incur a fee.
Many recycling facilities accept both ferrous and non-ferrous scrap. The scrap is fed into large shredders or crushers which break the scrap into smaller pieces. Ferrous scrap is separated from non-ferrous scrap and other materials using magnetic separators.
Steel is an alloy of iron plus a variety of other ingredients such as coke, limestone, manganese, aluminium and nickel, depending on the alloy's use. Pieces of steel scrap are chemically analysed to determine their alloy composition, and sorted by type.
Scraps are then melted down for reuse in the production of new iron and steel production.
1. Hyder Consulting (2009) Waste and Recycling in Australia: Amended report. Hyder Consulting, Melbourne, p. 134
2. Data for steel (Commercial & Industrial and Construction & Demolition recycling only) contained in Table 4 (p.14) Department of Environment, Climate Change and Water NSW (2010) Environmental Benefits of Recycling, DECCW, Sydney South
3. “Everyday” greenhouse gas emission savings expressed as number of kilometers driven by an average new passenger and light commercial vehicle (206.6g CO2e / km). National Transport Commission (2012) Carbon Dioxide Emissions from New Australian Vehicles 2011 Information Paper
4. “Everyday” cumulative energy demand savings expressed as average household monthly electricity requirements (500 kWh). 1GJ LHV = 278kWh (GJ LHV = Giga-joules of fossil energy (low heating value); kWh = Kilowatt hour)
5. “Everyday” water savings corresponding to average sized bath tubs (0.175 kL capacity). Steel recycling generates a small water impact. This impact is due to steel production from virgin sources generating blast furnace slag which in turn is used in concrete production as a substitute for cement. When recycling is undertaken, this process no longer occurs, so concrete production must revert to cement in place of blast furnace slag. Relatively, cement production is a water intensive process, so this results in recycling actually increasing water use in the concrete industry. Although technically adequate from a Life Cycle Assessment perspective, further investigation may be required to confirm that this would indeed be the result.
6. “Everyday” solid waste savings represented by number of average sized wheelie bins (55kg capacity)