A Guide to Metal Recycling
All metals can be recycled again and again without their integral properties being altered and this includes steel, copper, aluminium, silver, gold and brass, metals that we all see and use in everyday life.
Because scrap metals such as these therefore have a value, there will always be people who are willing collect them to then sell to recycling operations as a source of income. However, what is even more important is that as well as there being a financial incentive to make sure metal is recycled, there is also a sound environmental reason. Recycling metals means that not only are natural resources preserved, it also takes a lot less energy to process and then reuse rather than manufacturing new goods and products using raw material. Furthermore, the recycling process emits far less harmful gases such as carbon dioxide into the atmosphere leading to less pollution and a lower contribution to the effects of climate change.
Before we take a look at the entire recycling process, there are some interesting facts about metal and its use and reuse.
- In 2019, 32% of the crude steel that was produced worldwide was made by using recycled metal which means there is still a long way to go to making sure natural resources are preserved.
- Of everything that is recycled, steel and iron are the most recycled materials because not only are they easy to reprocess but it often involves the recovery of large structures rather than smaller individual pieces of metal thereby making it a more efficient and less time consuming process
- By using magnets, recyclers can easily sort metal from all other materials in the waste disposal process before that waste passes to other recycling facilities that would be unable to process metal
- The containers that are recycled the most throughout the world are aluminium cans so it’s worth remembering to always recycle those that you use
- Recycling just one aluminium can means that sufficient energy is saved that would power one 100 watt light bulb for almost 4 hours or a computer or television for 30 minutes
Metals that can be recycled
Metals fall into two categories – ferrous and non-ferrous. Ferrous refers to metals that contain iron while non-ferrous metals contain no iron at all. The most common types of ferrous metals are alloy steel, carbon steel, cast iron and wrought iron and the most used non-ferrous metals include copper, zinc, lead, tin and aluminium. Precious metals such as gold, silver, platinum, palladium and iridium fall into the non-ferrous category too since obviously these are pure metals and therefore contain no iron.
The process of metal recycling
Stage 1 – Collecting the metal
Because scrap metal has a higher value than other waste materials, it tends to be collected differently and then sold to scrapyards. In the USA, scrapped vehicles are the biggest source of ferrous metal for recycling but throughout the world other massive structures made of steel, ships, farm vehicles and equipment, railway tracks and household scrap metal can all be processed and recycled.
Stage 2 – Sorting the metal
After reaching a recycling facility, the scrap metals are sorted either manually or by using magnets or sensors in a purpose built machine. Even without sophisticated recycling equipment, it would be fairly easy for an entrepreneurial scrap merchant to sort metal by either using a magnet or by sorting the metal according to its colour and weight. As an example, aluminium will be light in weight and silver in colour and brass will be yellow and heavier. The value of any scrap metal can be enhanced by ensuring clean metals are separated from dirty metals prior to being processed.
Stage 3 – Processing the metal
So that metal can be processed efficiently, it first needs to be shredded which will aid the process of melting due to the shredded metal having a larger surface/volume ration. This is also important as it means the melting process uses less energy.
Stage 4 – Melting the metal
This stage involves each different type of metal being melted in a specific furnace that has been designed for that itl. Although this stage involves a great deal of energy being used, it is still considerably less than using raw material to produce metal. Depending on the size of the furnace and the amount of metal to be melted, this process can take anything from a few minutes to many hours.
Stage 5 – Purifying the metal
After the metal has been melted, it then needs to be purified to make sure it is free from contaminants and is therefore of a high quality. The most used method for this purification stage is electrolysis.
Stage 6 – Solidifying the metal
Once the melted metal has been purified, it is then put on a conveyor belt where it will cool and then solidify. It is at this stage that the metal is cast into certain shapes such as bars and blocks that are easy to use in the manufacture of other metal goods.
Stage 7 – Transporting the metal
Having been solidified, the metal is now ready to be used again and is transported to the factories and manufacturing plants to be used as the raw material to produce new products which, when they come to the end of their own useful life, will then enter the metal recycling process once again. Overall, the current metal recycling rate stands at 34% which is pretty poor when you consider that almost every type of metal is capable of being recycled. The challenge therefore remains as to how more scrap metal can be captured to then be recycled and this should involve raising public awareness and making community recycling facilities more accessible.
To help more people, especially businesses, to recycle more metal, we have developed The Green Alchemist which is a business tool that will help you to increase your revenue, save time and help you contribute to the zero waste economy and fight climate change.
Register on The Green Alchemist today.