The most recycled material in the world, steel is present in our daily lives in the form of cars, refrigerators and packaging, for example. More than 385 million tons are recycled on the planet per year, in Brazil alone around 200 thousand tons of post-consumer steel cans return for the recycling process.
In Brazil, as in the rest of the world, the steel scrap market is very solid, as the steel industries use the material to make new steel, that is, each steel plant is a recycling plant. Steel for recycling does not need to be completely free of contaminants, as steel mills have developed processes capable of eliminating them.
In European countries, such as Germany and Belgium, the recycling rate of post-consumer steel cans is above 95%. In Brazil, 47% of the total steel cans consumed are recycled, including food packaging, such as peas, corn and sardines, beverages, as well as cans of paint, spackling and chemical products. This index has been increasing thanks to the expansion of selective collection and environmental education programs. But how are steel cans recycled?
What is the steel can recycling process like?
To recycle steel food cans, just wash them and separate them from organic waste. It is recommended to make the most of the product until the can is completely empty, to avoid wasting food. As for paint cans, it is not necessary to wash them. The paint film that remains on the inner surface usually dries in about 24 hours and does not interfere with recycling.
All steel cans can be delivered to the municipal selective collection or forwarded to Prolata (a non-profit association that encourages the recycling of post-consumer steel cans), to collectors' cooperatives or to voluntary delivery points (PEVs). According to Juliana da Silva, vice-president of the Vitória do Belém cooperative, in São Paulo (SP), most of the steel cans received come from condominiums and houses. In 2020, Vitória do Belém has already received around seven tons of steel packaging. The steel cans are separated manually or using electromagnetic separators and then pass through sieves to remove contaminants.
Next, the steel packages are pressed into bales to facilitate transport by trucks to the recycling industries, that is, the steel mills. Upon arrival at the steel plant, the scrap is processed before going to electric or oxygen furnaces, heated to an average of 1550 °C. After reaching the melting point and reaching the liquid state, the material is molded into billets and metallic plates. The scrap takes just one day to be reprocessed and transformed back into steel blades used by various industrial sectors – from car assemblers to can factories. The material can be recycled infinitely, without causing mechanical losses (such as hardness and strength) or impairing quality.
“At Gerdau, thousands of tons of ferrous scrap are transformed into new products every day”, comments Carlos Vieira da Silva, Director of Raw Materials and Forestry at Gerdau. The use of recyclable raw materials is becoming more and more important. In 2019, Gerdau recycled more than 11 million tons of scrap at its plants in Brazil and the Americas. That is, 73% of the steel produced by it has ferrous scrap as its main raw material. “Steel can be recycled several times without losing quality, contributing to the preservation of natural resources”, says the executive. Gerdau's steel is consumed by several sectors, with emphasis on construction, infrastructure, industry, agribusiness and energy.
