Recycling Rates of Metals Must Increase to Reach Sustainability

Mass of aluminium cans being processed at a recycling plant.
••• Mint Images - Paul Edmondson / Getty Images

"Recycling Rates of Metals: A Status Report," says that recycling rates of metals are in many cases is discouragingly low. The report issued by the United Nations Environment Programme (UNEP) states that fewer than one-third of 60 metals studied have an end-of-life recycling rate above 50 percent and 34 elements have a recycling rate of less than one percent. Many of these metals, however, are crucial to clean technologies such as batteries for hybrid cars to the magnets in wind turbines, according to the authors of the study.

“In spite of significant efforts in a number of countries and regions, many metal recycling rates are discouragingly low, and a ‘recycling society’ appears no more than a distant hope,” states the report. It notes that unlike some other resources, metals are “inherently recyclable,” which makes the poor performance all the more frustrating.

With efficient recycling, metals can be used over and over again, minimizing the need to mine and process virgin materials while decreasing energy and water requirements. Success in raising levels of recycling worldwide would benefit the transition to a low carbon, resource efficient Green Economy while assisting in the creation of green jobs.

Some studies suggest that recycling metals are between two and 10 times more energy efficient than smelting the metals from virgin ore. At the same time, extraction alone currently accounts for seven percent of the world’s energy consumption, with emissions contributing significantly to climate change.

Recycling Rates Vary

The report indicates lead as the most widely recycled metal, with nearly 80 percent of products containing lead – mainly batteries – being recycled at the end of their useful life. Iron and other main components of steel and stainless steel, as well as platinum, gold, silver and most other precious metals, all have recycling rates above 50 percent.

There are, however, significant variations in recovery by the material stream. While 70 to 90 percent of gold in industrial applications is recycled, for example, only 10 to 15 percent of gold is recycled from electronic goods.

For many other metals, the recovery rate is very low. Thirty-four out of sixty elements included in the study had recycling rates of less than 1 percent.

“In principle, the amount of recycling of metal offsets the same amount of metals that need to be mined,” says Guido Sonnemann of UNEP, an innovation and product lifecycle management expert. “Because demand for metals overall is increasing, recycling can’t offset all mining but can contribute to a more sustainable mining industry.”

Recommendations Towards Improving Recovery

The study offers recommendations on how recycling could be increased worldwide. These suggestions include:

Also recommended is the ongoing improvement of recycling technologies and collection systems to keep pace with “ever more complex products created with an increasingly diverse range of metals and alloys.”

Recycling Rates

Of the 60 elements studied, only 18 had greater than 50 percent recovery, with three items in the 25-50 percent recovery, three elements in the 10-25 percent category, two elements at 1-10 percent, 34 elements less than 1 percent.

Top Ten Metals Recovered

  1. Lead (main use: batteries)
  2. Gold (main uses: jewelry, electronics)
  3. Silver (main uses: electronics, industrial applications (catalysts, batteries, glass/mirrors), jewelry);
  4. Aluminum (main uses: in construction and transportation)
  5. Tin (main uses: cans and solder)
  6. Copper (main uses: conducting electricity and heat)
  7. Chromium (main use: stainless steels)
  8. Nickel (main uses: stainless steels and superalloys)
  9. Niobium (main uses: high strength / low alloy steels and superalloys)
  10. Manganese (main use: steel)