Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel
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Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel
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Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel
#2I don’t get this. We already use direct reduction using about half hydrogen, and that can be increased to over 90%. Producing ammonia via the Haber process means losing 40% or so of the energy (and potentially more as you convert it back), so why not just use hydrogen directly? Simply because moving hydrogen is harder than ammonia? I think it makes way more sense to just make and use the hydrogen on-site.
Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel
#3I don’t get this. We already use direct reduction using about half hydrogen, and that can be increased to over 90%. Producing ammonia via the Haber process means losing 40% or so of the energy (and potentially more as you convert it back), so why not just use hydrogen directly? Simply because moving hydrogen is harder than ammonia? I think it makes way more sense to just make and use the hydrogen on-site.
You said it: transporting, storing, and otherwise handling ammonia is easier than H2. Amd handling a lump of coke is even easier, which is why we started there.
Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel
#4I don’t get this. We already use direct reduction using about half hydrogen, and that can be increased to over 90%. Producing ammonia via the Haber process means losing 40% or so of the energy (and potentially more as you convert it back), so why not just use hydrogen directly? Simply because moving hydrogen is harder than ammonia? I think it makes way more sense to just make and use the hydrogen on-site.
i think the question is how far you are shipping the hydrogen. If, say, people are making hydrogen in (say) the Middle East and shipping it to (say) Europe then the overhead of liquifying or compressing H2 is on the same order as converting to ammonia. In that paper they demonstrate that you can just use the ammonia directly to reduce iron and not have a separate system to convert it back.
If you have a big wind power or solar complex like the ones being built in the North Sea or Australia you might be better off using hydrogen directly.
Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel
#5I don’t get this. We already use direct reduction using about half hydrogen, and that can be increased to over 90%. Producing ammonia via the Haber process means losing 40% or so of the energy (and potentially more as you convert it back), so why not just use hydrogen directly? Simply because moving hydrogen is harder than ammonia? I think it makes way more sense to just make and use the hydrogen on-site.
This isn't using ammonia to transport hydrogen; the nitrogen is what's reacting with the iron.
And yes, ease of transportation and reactivity is a big motivator.
From the abstract:
"Ammonia is an annually 180 million ton traded chemical energy carrier, with established transcontinental logistics and low liquefaction costs. It can be synthesized with green hydrogen and release hydrogen again through the reduction reaction."
Also: "The authors show that ammonia-based reduction of iron oxide proceeds through an autocatalytic reaction, is kinetically as effective as hydrogen-based direct reduction, yields the same metallization, and can be industrially realized with existing technologies."
Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel
#6I don’t get this. We already use direct reduction using about half hydrogen, and that can be increased to over 90%. Producing ammonia via the Haber process means losing 40% or so of the energy (and potentially more as you convert it back), so why not just use hydrogen directly? Simply because moving hydrogen is harder than ammonia? I think it makes way more sense to just make and use the hydrogen on-site.
i think the question is how far you are shipping the hydrogen. If, say, people are making hydrogen in (say) the Middle East and shipping it to (say) Europe then the overhead of liquifying or compressing H2 is on the same order as converting to ammonia. In that paper they demonstrate that you can just use the ammonia directly to reduce iron and not have a separate system to convert it back. If you have a big wind powe…
I would guess that even better than shipping ammonia or hydrogen to European steel plants would be to build new steel plants near the hydrogen producers, wherever they may be, and shipping iron ore there while shipping steel back out. Since iron ore and steel are much denser than either ammonia or hydrogen and do not need pressure vessels or chilling they can be shipped at lower speeds (save transport energy consumption) and save money too.
Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel
#7Earlier quoted context omitted.
i think the question is how far you are shipping the hydrogen. If, say, people are making hydrogen in (say) the Middle East and shipping it to (say) Europe then the overhead of liquifying or compressing H2 is on the same order as converting to ammonia. In that paper they demonstrate that you can just use the ammonia directly to reduce iron and not have a separate system to convert it back. If you have a big wind powe…
I would guess that even better than shipping ammonia or hydrogen to European steel plants would be to build new steel plants near the hydrogen producers, wherever they may be, and shipping iron ore there while shipping steel back out. Since iron ore and steel are much denser than either ammonia or hydrogen and do not need pressure vessels or chilling they can be shipped at lower speeds (save transport energy consumpt…
I'm asking this 100% from a place of curiosity because I don't know the answer. From iron ore to steel, how much waste is there? If the waste fraction is large, people might balk at the idea of either leaving that waste behind in the hydrogen-host country or burning fossil fuels to ship it around to have a carbon-free extraction process.
Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel
#8I don’t get this. We already use direct reduction using about half hydrogen, and that can be increased to over 90%. Producing ammonia via the Haber process means losing 40% or so of the energy (and potentially more as you convert it back), so why not just use hydrogen directly? Simply because moving hydrogen is harder than ammonia? I think it makes way more sense to just make and use the hydrogen on-site.
i think the question is how far you are shipping the hydrogen. If, say, people are making hydrogen in (say) the Middle East and shipping it to (say) Europe then the overhead of liquifying or compressing H2 is on the same order as converting to ammonia. In that paper they demonstrate that you can just use the ammonia directly to reduce iron and not have a separate system to convert it back. If you have a big wind powe…
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Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel
#9Earlier quoted context omitted.
i think the question is how far you are shipping the hydrogen. If, say, people are making hydrogen in (say) the Middle East and shipping it to (say) Europe then the overhead of liquifying or compressing H2 is on the same order as converting to ammonia. In that paper they demonstrate that you can just use the ammonia directly to reduce iron and not have a separate system to convert it back. If you have a big wind powe…
I would guess that even better than shipping ammonia or hydrogen to European steel plants would be to build new steel plants near the hydrogen producers, wherever they may be, and shipping iron ore there while shipping steel back out. Since iron ore and steel are much denser than either ammonia or hydrogen and do not need pressure vessels or chilling they can be shipped at lower speeds (save transport energy consumpt…
This is how Iceland exports the bulk of its hydroelectric energy, but they use aluminum
Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel
#10I don’t get this. We already use direct reduction using about half hydrogen, and that can be increased to over 90%. Producing ammonia via the Haber process means losing 40% or so of the energy (and potentially more as you convert it back), so why not just use hydrogen directly? Simply because moving hydrogen is harder than ammonia? I think it makes way more sense to just make and use the hydrogen on-site.
> Producing ammonia via the Haber process means losing 40% or so of the energy
This seems wrong. I believe that green HB process would be 80%-90% efficient since the heat is re-used? I have read conflicting papers.
Of course, HB is still a capex-heavy process.
Maybe the 40% number is for fossil methane to ammonia?