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Comment by simplotek | Hacker News Reader

> (...) brought to the USA, melted in an arc furnace, and suddenly it's "made in USA"!

I don't think this assertion makes sense. Making steel is way more than getting iron and mixing it up with some carbon. You need special manufacturing processes to get specific alloys and treatments to get the properties and reliability you expect. Recycling and importing steel is like importing a raw material.

Your comment reads like "This let's them do things like claim burger made in USA when in fact the burger buns were made with corn from Ukraine and meat from Argentina".

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I'm guessing the implication is that it allows concealment of CO2-intensive new steel production.

If you take "raw" steel and process it, you can look green from your operations...

... just ignore the upstream producers using the lowest-cost but carbon-dirty processes.

Recycling steel in an arc furnace is cheaper and uses less power than making new steel. The only reason we’re not on 100% recycled steel is because demand outstrips supply. Those upstrram processes are more expensive!

I don't think anyone is arguing against recycling steel. The argument is against producing new steel, shipping it across the world, and then immediately scrapping and recycling it, as a way to claim it is both green and locally produced.

Does this actually happen, or it's just a hypothetical? (in other words, do you have some links?)

But if the recycled steel is cheaper, who would spend a bunch of money to take an expensive input, and create a cheap output? It doesn’t economically make sense

Absolutely no one does that.

Even the cheapest, dirtiest iron ore from Brazil or Australia can't compete with steel scrap in the US or EU because recycling uses less than quarter of the total power and produces a fifth of the emissions that producing virgin steel does. You can't greenwash something when the green version costs way less than the polluting one. It'll be written on the price tag!

But as you said, demand outstrips supply.

> and then immediately scrapping and recycling it

You seem to be confused. Using steel as a raw material is not "scrapping and recycling". The value of steel in engineering applications is that you can trust that the properties of a particular alloy used to make a particular part will comply with the specs. Steel from China is renowned for being unreliable and failing to comply with standardized properties.

https://www.cdmg.com/building-faqs/why-using-cheap-steel-is-...

You avoid that risk by importing steel as a raw material and use that to actually produce reliable steel. If low-quality steel is cheap enough so that after recycling it you can still make a profit then it's a sound business decision and the whole economy benefits.

Is that lifecycle or at-plant to output?

My impression was most of the recycling energy inputs were in collection, sorting, and shipping.

Lifecycle. The amount of energy required to melt metals and/or extract them from ore via electrolysis will always dominate the overall numbers whether it's recycled or produced new.

Do you have any links? Would love to learn more.

See the Department of Energy's report "Theoretical Minimum Energies To Produce Steel for Selected Conditions" [1] and compare with the numbers in the wikipedia article on energy efficiency in transportation [2].

The table on page 15 lists the megajoules per ton required to produce steel with various amounts of scrap content. When made with 100% recycled scrap, steel requires "only" 1,289 megajoules per ton. Based on that wiki page rail requires 150 kilojoules per metric ton kilometer so a ton of steel costs only about 75 megajoules to transport a thousand km.

Large container ships use half that much energy so even if the steel scrap must be shipped overseas and back ten thousand km, it'd still be under 400 megajoules for transportation versus over 1,200 megajoules for recycling. The rest of the costs like sorting are negligible.

In practice it takes at least 2,500-3,000 megajoules per ton of steel since the scrap has to be mixed with other sources of iron when there's not enough scrap to go around. The number for aluminum are a lot worse, on the order of ten times more megajoules per ton to extract alumina from ore via electrolysis versus smelting aluminum scrap, which already requires 10x the energy of steel.

[1] https://www.energy.gov/eere/amo/articles/itp-steel-theoretic...

[2] https://en.wikipedia.org/wiki/Energy_efficiency_in_transport

> If you take "raw" steel and process it, you can look green from your operations...

I'm not sure the people complaining about Chinese steel imports are thinking about environmental footprint. It's all a chain of simplistic economic reasoning to complain that they import a product instead of producing it.

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