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Comment by nandomrumber | Hacker News Reader

It's entirely possibly to make steel with an electric arc furnace powered by your choice of energy input.

And steel is 100% recyclable, indefinitely.

Hard to beat.

“your choice of energy input” is carrying a lot of weight in your statement. producing steel from iron ore is extremely energy intensive. it’s true that once produced, recycling steel is less expensive.

but steel doesn’t store carbon (except the small carbon input used to turn iron to steel)

wood, on the other hand, is a carbon sink.

Remember to factor in all the trees that will need to be cut down in order to provide the wood.

Of course, over time we can increase the amount of industrial forest, but that will take 40-50 years.

That's the whole point, to remove trees from the land, so new trees can grow and extract carbon from the atmosphere.

no, wood is not a carbon sink. its gets turned back into co2 as it decomposes.

Sure but the infrastructure required to do that is probably (my guess) more extensive than a wood press and some chemicals

> > a more carbon friendly alternative to steel.

> Hard to beat.

Since wood is actually carbon negative, it still manages to beat steel.

actually recycling steel is not 100% lossless in that everytime you decrease purity which leads to a point where the still can only be used in low grade products. building materials is usually one of the low tiers though.

Iron ore is contaminated with all sorts of crap, far worse than scrap steel. If what you are saying were true, it would be impossible to make high-grade steel from iron ore.

Impossible in an electric furnace (which could be powered by renewable sources).

Virgin steel requires the higher temperatures of a coke-fed blast furnace.

It does require a reducing gas such as the CO produced by coke, but an electric arc furnace can of course reach higher temperatures. Iron can be smelted successfully from ore even without a high enough temperature to melt it, as in bloomery smelts, but the quality of the resulting metal is quite uneven.

then again we have hundreds of years of economies of scale in place for that process, and (presumably) far less for repurifying steel. I'm not saying it's not possible, of course it's not, but is it financially viable with current infrastructure? I'm genuinely asking, I don't know anything about this.

I'm no expert either but I think you can use the same process, though most steel recycling is instead done more cheaply done in EAFs.

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