Almost all types of ferrous metals can – and should – be recycled. The process serves to reduce not only landfill waste, but also manufacturing costs and the labor and energy required to extract additional raw materials. Fortunately, this recycling can even be done without compromising the strength and integrity of the reclaimed product. To see how, let’s run through an example with steel – the most recycled metal in the world, and easily the most widely used and versatile, with applications from the creation of common household items to the building of massive skyscrapers.
How is Steel Manufactured?
The creation of steel solely from raw components requires the combination of iron ore, limestone, and coke (a coal-based fuel) in a furnace, where it is smelted down to remove impurities and add carbon. Today, much of the steel we use is produced by recycling existing materials – for each ton of reused steel, we’re able to save 120 pounds of limestone, 1,400 pounds of coke, and 2,500 pounds of iron ore, according to the American Iron and Steel Institute
There are two primary methods of creating steel with reclaimed scrap: through an EAF (Electric Arc Furnace) or BOF (Basic Oxygen Furnace).
In the EAF process, the raw material is almost entirely scrap steel. High-powered electric arcs quickly melt the material down to liquid crude steel, after which it is refined further in secondary steelmaking processes. Much of the steel used in construction, such as reinforcement bars, steel plates, and structural beams, is made through the EAF process, since the end result produced is incredibly strong.
The BOF process, on the other hand, uses only about 30% recovered steel at most. Here, molten iron is combined with pure oxygen to blow out impurities. The steel produced by this method is used to make industrial drums, pails, cans, refrigerator encasements, and automobile fenders.
What Type of Scrap Metal can be used?
Thanks to steel’s versatility and popularity, there is a huge supply of scrap available cheaply. Common sources for recycled steel components include:
- Bodies of old vehicles
- Old machinery, engine blocks, pipes, and iron baths
- Domestic scrap, such as old appliances, cans, water tanks, roofing sheets, etc.
- Factory waste that remains after shaping or drilling metal
- Industrial waste and commercial scrap such as old columns, beams, channels, plates, implements and more
How is this Material Recovered?
Since iron and steel have magnetic properties, they can be easily separated from other waste. Once segregated, these metals are kept in scrapyards and by heavy machinery, for ease of transport and to reduce necessary space on the conveyer belts that feed blast furnaces.