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Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

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61–70 of 86 posts

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#61
post #53

Earlier quoted context omitted.

Sure. But we also can synthesize methane from captured carbon dioxide and green hydrogen. It's still more expensive than fossil methane, but it's getting cheaper. But we can start transitioning factories to use methane right now, starting from fossil methane and slowly moving to greener sources.

You're suggesting unworkable processes that would take an absolute crapton of energy and be very expense.

Uhm... Which one? Reduction of iron ore with methane is energetically as good as anything else.

Synthetic methane is estimated right now to be about 2.5x the cost of fossil one when deployed at scale: https://www.sciencedirect.com/science/article/pii/S187551002...

This is pretty reasonable.

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#62

Earlier quoted context omitted.

Exactly, I struggle to see any situation, barring mismanagement or disaster, where you should be shipping tankers full of hydrogen byproducts like ammonia and losing most of the energy in the process. We are currently importing all the natural gas in Europe, and both the price and carbon footrpint are more than double of what pipeline delivered from Russia. You could build a pipeline from the middle east to Europe fo…

Hydrogen, being so small, penetrates directly through the molecular structure of steel and in the process causes embrittlement of the steel. Is a long distance H2 pipeline a solved problem using alternate materials?

It is not. Thankfully the electricity required for hydrolysis can either be moved around or created sufficiently close to a steel plant.

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#63
post #50
post #3

Earlier quoted context omitted.

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.

If hydrogen is electrolytic you can as well make it on site. Steel mills are continuous operations and there is not much need to pool/smooth demand.

Shifting electric prices due to wind power is a strong motivation to pool it though.

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#64
post #18

Reduction of iron ore with carbon monoxid in closed loop: • Decarbonisation of BF-BOF through thermochemical closed carbon looping. • Demonstration of mass and energy flows of thermochemical BF-BOF system. • 88% emissions reduction of UK steel industry through £720 million investment. • Decarbonisation without retiring of existing BF-BOF, reducing stranded assets. • After 5 years, £1.28 billion savings and total UK-w…

>In conclusion, this paper aims to demonstrate the first principal calculations of coupling a thermochemical carbon dioxide splitting cycle with a steel production facility for cost-effective steel decarbonisation.

It's an interesting idea. But let's be clear: it's an idea. The scientific literature contains a lot of good ideas.

By contrast the OP paper is actually an experimental demonstration of reduction with ammonia. A bird in the hand is worth two in the bush.

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#65

Lots of refs here to the Haber-Bosch process in creating the ammonia... for those interested in a break down of what it is - https://www.carbonbrief.org/qa-what-does-the-worlds-reliance... ...sort of feels like kicking the can down the road if this is how the ammonia is generated for "Green Steel".

From article: " Currently, ammonia is synthesized through the Haber–Bosch process by converting hydrogen and nitrogen into ammonia. In this process, hydrogen is mainly produced via steam methane reforming. This fact makes the process of fossil-fuel-based ammonia synthesis very carbon dioxide intensive, accounting for ≈1% of the global carbon dioxide emissions.[11, 16] Yet more sustainable ammonia synthesis pathways a…

Haber-Bosch seems to be only feasible at large scale. It would be great to make this scale down and be more efficient.

It's the secret to a whole lot of ways to combat rising carbon.

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#66
post #49

There is already direct hydrogen reduction, why bother with ammonia? At least hydrogen can be from solar electricity, not so much for ammonia.

Regarding your second sentence in particular, the Haber Bosch process already make ammonia out of hydrogen. That it usually take hydrogen produced out of methane is something that can be changed.

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#67

Earlier quoted context omitted.

Exactly, I struggle to see any situation, barring mismanagement or disaster, where you should be shipping tankers full of hydrogen byproducts like ammonia and losing most of the energy in the process. We are currently importing all the natural gas in Europe, and both the price and carbon footrpint are more than double of what pipeline delivered from Russia. You could build a pipeline from the middle east to Europe fo…

Hydrogen, being so small, penetrates directly through the molecular structure of steel and in the process causes embrittlement of the steel. Is a long distance H2 pipeline a solved problem using alternate materials?

thats one reason why ammonia is a good choice. the storage requirements are much kinder to the transporter

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#68
post #56

Earlier quoted context omitted.

The ammonia has a purpose on its own, as fertilizer. The nitrogen used to make it, is also freely pulled from the atmosphere

It’s also great for making explosives. What?

A knife is great for spreading butter on toast.. also really good for stabbing as well.

your point is kinda silly, if thats the point you were trying to make.

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#69
post #45

Earlier quoted context omitted.

From article: " Currently, ammonia is synthesized through the Haber–Bosch process by converting hydrogen and nitrogen into ammonia. In this process, hydrogen is mainly produced via steam methane reforming. This fact makes the process of fossil-fuel-based ammonia synthesis very carbon dioxide intensive, accounting for ≈1% of the global carbon dioxide emissions.[11, 16] Yet more sustainable ammonia synthesis pathways a…

I work at a company that is creating better electrolyzers for this process. Ammonia producers are clamoring for this technology. It works, and it is happening!

Could ammonia be used for stable seasonal storage of energy?

The abstract suggests that ammonia is much nicer to transport and store than hydrogen. If we can use it to store summer solar to run winter heat-pumps with a low roundtrip efficiency but even lower costs per kWH of capacity it could really help.

Re: Reducing Iron Oxide with Ammonia: A Sustainable Path to Green Steel

#70
post #63
post #50

Earlier quoted context omitted.

If hydrogen is electrolytic you can as well make it on site. Steel mills are continuous operations and there is not much need to pool/smooth demand.

Shifting electric prices due to wind power is a strong motivation to pool it though.

So far it's easier and more efficient to reserve/contract some hydro (dam) storage than store/pool hydrogen for continuous operations.
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