Many economists expect President Donald Trump's tariffs on imported steel and aluminum to increase what American companies and consumers pay for those metals and the goods made from them.
Dozens of companies have already said they will have to fire workers or even go out of business. And, as the retaliatory tariffs Canada, Japan, Mexico and other countries have announced underscore, the US is heading for a trade war with the nation’s closest allies.
But having spent the last eight years researching how to make the steel and aluminum industries more efficient, I believe it’s possible for the US to slash imports of these metals not by imposing duties but by boosting the reuse and recycling of old metal products.
Making far more of the nation’s discarded steel and aluminum scrap as good as new would have many advantages aside from its diplomatic dividends, such as cutting pollution and energy consumption.
The US made 82 million metric tonnes of steel in 2017, enough to form a continuous steel beam that could circle the globe eight times. Some 68% of that steel was made from scrap metal.
The 4.4 million metric tonnes of aluminum the US made in 2017 could be turned into a stack of soda cans tall enough to reach Mars. Some 83% of that aluminum was from recycled metal.
Regardless of whether those assertions are reasonable, I believe that these imports, nearly two-thirds of the aluminum and about one-third of the steel the US consumed in 2017, could be nearly entirely displaced if America were to step up its reuse of scrap metal.
Making steel from ore requires making iron first using coke, a high-carbon fuel made by baking coal at over 1,000 degrees Celsius. Coke removes oxygen from the iron oxide in the ore, producing iron but inevitably creating carbon dioxide, a greenhouse gas then released to the atmosphere.
Between the bauxite mining, refining, smelting and casting processes, the aluminum industry is among the world’s most energy-intensive. Despite some promising technological breakthroughs, the simplest way to make this flexible, durable and strong metal with less power and fewer emissions is by recycling the metal.
So recyclers will try to separate discarded old products into piles of different metals before adding any to their furnaces. For example, they shred old cars into small pieces with large mechanical shears before ferreting out the steel they want to recycle with magnets.
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