Is There a Greener Way to Produce Iron? (scitechdaily.com) 37
"Using electrochemistry, University of Oregon researchers have developed a way to make iron metal for steel production without burning fossil fuels..." the University of Oregon wrote last year. "Decarbonizing this step would do roughly as much to reduce greenhouse gas emissions as converting every gas-guzzling vehicle on the roads to electric... If scaled up, the process could help decarbonize one of the largest and most emissions-intensive industries worldwide," replacing carbon-spewing industrial blast furnaces.
Paul Kempler, their research assistant chemistry professor, added "The reason we got excited about this chemistry, is that our reactants are two things that are very cheap: saltwater and iron oxide." And this week he announced that "We actually have a chemical principle, a sort of guiding design rule, that will teach us how to identify low-cost iron oxides that we could use in these reactors."
"Those reactions conveniently also produce chlorine, a commercially valuable byproduct," writes SciTechDaily, in a new follow-up report this week: In their latest study, the researchers focused on improving the process by identifying which types of iron oxides make the reaction more cost-effective, an essential step toward scaling the method for industrial use.... In lab tests, the difference was striking: "With the really porous particles, we can make iron really quickly on a small area," Goldman said. "The dense particles just can't achieve the same rate, so we're limited in how much iron we can make per square meter of electrodes...."
To take their process beyond the lab, Kempler's lab is working with researchers in other fields. A collaboration with civil engineers at Oregon State University is helping them better understand what's needed for the product to work in real-world applications. And collaboration with an electrode manufacturing company is helping them address the logistical and scientific challenges of scaling up an electrochemical process. "I think what this work shows is that technology can meet the needs of an industrial society without being environmentally devastating," Goldman said.
"We haven't solved all the problems yet, of course, but I think it's an example that serves as a nucleation point for a different way of thinking about what solutions look like. We can continue to have industry and technology and medicine, and we can do it in a way that's clean — and that's awesome!"
Paul Kempler, their research assistant chemistry professor, added "The reason we got excited about this chemistry, is that our reactants are two things that are very cheap: saltwater and iron oxide." And this week he announced that "We actually have a chemical principle, a sort of guiding design rule, that will teach us how to identify low-cost iron oxides that we could use in these reactors."
"Those reactions conveniently also produce chlorine, a commercially valuable byproduct," writes SciTechDaily, in a new follow-up report this week: In their latest study, the researchers focused on improving the process by identifying which types of iron oxides make the reaction more cost-effective, an essential step toward scaling the method for industrial use.... In lab tests, the difference was striking: "With the really porous particles, we can make iron really quickly on a small area," Goldman said. "The dense particles just can't achieve the same rate, so we're limited in how much iron we can make per square meter of electrodes...."
To take their process beyond the lab, Kempler's lab is working with researchers in other fields. A collaboration with civil engineers at Oregon State University is helping them better understand what's needed for the product to work in real-world applications. And collaboration with an electrode manufacturing company is helping them address the logistical and scientific challenges of scaling up an electrochemical process. "I think what this work shows is that technology can meet the needs of an industrial society without being environmentally devastating," Goldman said.
"We haven't solved all the problems yet, of course, but I think it's an example that serves as a nucleation point for a different way of thinking about what solutions look like. We can continue to have industry and technology and medicine, and we can do it in a way that's clean — and that's awesome!"
Solar sails and solar mirrors mining asteroids (Score:2)
There is plenty of iron, and untouched rare earths, shown in spectrographic analysis of asteroids. Mine them in space, pay some attention to tailings and exudates, and mining should be safe for thousands or even millions of years depending on the amount needed. Use the results directly in space for space construction, mine Saturn's rings for ice for life support and reaction mass, and we could have a real space industry.
Re:Solar sails and solar mirrors mining asteroids (Score:5, Interesting)
You'd need to decarbonize the rocket fuel too to have a net savings.
For processing pig iron and scrap, we can reduce the use of coke in a cupola furnace by mostly switching iron production over to electric arc furnace or induction furnace. (there's a few other options as well). This transition has partially occurred already, but we still burn a lot of coke for iron in the world.
Re: (Score:3)
Because iron needs carbon to become steel.
Re:Solar sails and solar mirrors mining asteroids (Score:5, Interesting)
Sure, but you add it with pig iron. Burning most of the carbon by heating your iron with coke is not an efficient use of your carbon.
Disclaimer: I used to work in an iron foundry 25 years ago, gray iron green sand casting with a coke cupola and two disamatic lines. So perhaps my information is very out of date.
Re:Solar sails and solar mirrors mining asteroids (Score:5, Informative)
Considering how old blast furnace technology is at this point, the age of Bessemer and cupola furnaces, etc..
Your information does not seem out of date. It'd only be out of date once most places have switched to different steel making processes such as the electrochemical mentioned here, hydrogen, etc...
Basically, blast furnace produces pig iron. Pig iron has too much carbon for most uses. Around double what is good for steel.
A Bessemer/open-hearth/cupola furnace is used after the blast furnace to burn away the excess carbon (stuff is commonly added to help with this, like limestone). Wrought iron is made by literally heating the metal to glowing and beating on it to drive out the carbon.
But consider - this means heating the iron past the melting point TWICE. That's a lot of energy, which only makes sense when you have access to cheap coke.
Using an electrochemical process like described here allows you to fulfill the function of both the blast furnace and cupola in one step, because it results in low-carbon iron the first time around. It doesn't even require healing the iron to the melting point.
This way you only need to melt it once, not 2 or even 3 times, to get the alloy you want. You take the low carbon iron you want and melt it once with the alloying compounds you want (which can include carbon) in an electric furnace of some sort (arc or induction). Much more energy efficient.
I'll note that I'm aware that there are 'continuous processes' today where they do everything without letting the iron cool too much, but that isn't universal. Also complicating matters is the routine recycling of iron and steel, because that's a lot more efficient than trying to make all new steel, and it's often a complicated mix of recycled steel, new iron, and proprietary testing so they know what to chuck into the mix to get the right alloy out.
I still remember bits of the "dirty jobs" episode where they had Mike chucking bags of materials into the molten iron to get the alloy right. Didn't bother opening the bags - the iron just basically disintegrated the bags instantly, making for only an insignificant addition of carbon.
Re: (Score:3)
Iron needs very little carbon to become steel, and the carbon is sequestered within the metal. It's a carbon sink.
Current iron production emits lots of CO2 because of the fuel used to provide the required heat to split the iron from the oxygen, and the use of carbon as a convenient reactant to soak up the liberated oxygen. Both are addressable.
Re: (Score:3)
Electric arc furnace (EAF) steel made from scrap tends to have higher levels of certain residual contaminants compared to virgin steel made from ore via blast furnace (BOF).
Key differences:
More common in EAF/scrap steel:
Copper (Cu) – from wires, motors, plumbing
Tin (Sn) – from food cans, coatings
Chromium (Cr), Nickel (Ni), Molybdenum (Mo) – from stainless/alloy scrap
Phosphorus (P) and Sulfur (S) – vary by scrap quality, harder to control
Lead (Pb), Zinc (Zn) – from coatings, bat
Re: (Score:3)
You'd need to decarbonize the rocket fuel too to have a net savings.
Where the carbon in burning H2 and O2? :-)
Also, the rocket fuel will largely be produced in space too. There's water up there too.
Re: (Score:1)
Most of the H2 produced today is from methane (which is really just another name for natural gas), the carbon is "burned off" before the rocket reaches the launch pad.
Because liquid H2 is not fun to deal with most rockets today are using methane or RP-1 as fuel in spite of the hit to efficiency of the rocket. If the H2 they'd use otherwise comes from methane anyway then by using methane they are likely emitting less carbon into the air because that energy in the carbon bonds helps in getting the rocket to
Re: (Score:2)
Most of the H2 produced today is from methane (which is really just another name for natural gas), the carbon is "burned off" before the rocket reaches the launch pad.
I think you a missing the detail that we are talking about rocket fuel being used in space. If we are mining asteroids for metals we can also be mining them for fuel. And returning things to earth doesn't really require fuel. For example, the Space Shuttle was a glider on return.
Because liquid H2 is not fun to deal with most rockets today are using methane or RP-1 as fuel ...
Asteroids can contain methane too.
Re: (Score:2)
Re: (Score:2)
Yep, and then they rebel and make giant green monoeyed robots with plasma axes and australia gets wiped out of the map.
Also some bad things may happen as well.
Re: (Score:2, Interesting)
Humans can't live in space. What your describing has other problems too but, even if it did work, it wouldn't solve the problem of needing iron on earth without destroying the planet.
Globally, we produce billions of tons of iron every year. You can't dump billions of tons of material from orbit and not decimate the planet, so that leaves you trying to build enough rockets to land billions of tons of iron every year. The environmental damage just from all the rocket exhaust would be enough to wipe out hum
Re: (Score:1)
You wouldn't need rockets to land materials. A parachute works for that sort of stuff. I'd tend to think that a properly shaped iron projectile that is aimed in a particular way could be dropped into the ocean in a safe and predictable manner without needing anything special.
That said, it's probably still cheaper to make the iron and steel here on earth for local needs for the foreseeable future.
Especially with processes like this drastically reducing the energy required.
Re: (Score:2)
I'd tend to think that a properly shaped iron projectile that is aimed in a particular way could be dropped into the ocean in a safe and predictable manner without needing anything special.
Except, you know, something to stop it sinking.
Re: (Score:2)
You wouldn't need to stop it from sinking, just drop it into a fairly shallow bit of ocean. Then you can hook onto it with cables and floatation packs and haul it where you need it. Maybe a void in the center at a vacuum?
That said, I'm really curious about the flamebait mod. Not needing a rocket just seems common sense.
The iron/steel would get really hot during re-entry, but unlike, say aluminum, steel can withstand a huge amount of heat. Especially if your willing to allow a few percent to ablate away.
Re: (Score:2)
Billions of tons of flaming hot steel slamming into the shallow parts of the ocean (which happens to be where the majority of marine life lives).
Great plan. What will we do when we've killed everything?
Re: (Score:2)
And what, pray tell, will the parachutes be made of? Nylon isn't easy to come by in space.
Rockets are for ascent. Gravity is for descent. (Score:2)
You can't dump billions of tons of material from orbit and not decimate the planet, so that leaves you trying to build enough rockets to land billions of tons of iron every year.
Uh, no. Squishing humans land in an uncontrolled metal box with a parachute. Refined metals can be returned in a far simpler box. A recyclable metal box, part of the delivery. Parachutes, an unmanned glider (a box with wings, all recyclable metal), ... we just need to make the impact "gentle" in the asteroid impact sense, which can be far more violent than the squishy human landing sense.
The environmental damage just from all the rocket exhaust would be enough to wipe out human civilization.
Rockets are for ascent. Gravity is for descent.
Re: Solar sails and solar mirrors mining asteroids (Score:1)
The best way to become a space millionaire is to start as a billionaire. Do you think there's a reason these space fantasies never happen despite decades of predictions like yours?
If you still think it's so easy, go on Shark Tank or propose it to your bank.
After the laughter stops, brush up on high school physics.
Energy (Score:2)
There is plenty of iron, and untouched rare earths, shown in spectrographic analysis of asteroids.
Yes there is, the problem as always is energy. The energy costs to get mining equipment to orbit are huge and then there are the costs to land the materials back on Earth again. You cannot simply launch them at Earth since a huge amount would burn up in the atmosphere causing pollution and what landed would have to be dug up again and, if large enough or frequent enough, would also cause more pollution as well as devastating areas. So you also have to use fuel to transport the minerals to Earth and to then
A valid case for hydrogen (Score:5, Informative)
Traditional Iron/Steel making uses coke, which is basically highly purified coal.
This is because most iron out there is oxidized, rust basically. So, you need to reduce it (remove the bonded oxygen). Traditionally, basically heat the iron up (using coke as fuel) to the point that the molecular bond with the iron is weakened, then it transfers over to the carbon to form carbon monoxide and dioxide.
However, there are alternative ways, such as using hydrogen.
https://www.sciencedirect.com/... [sciencedirect.com]
The benefits of doing an electrochemical method, from this article and previous I've read on the subject, is that you don't need to melt the metal in the process. Avoiding having to use that much heat drastically reduces the energy cost of the process, making using green electricity to do it a lot more attractive than having to heat it up to around 3,000 F/1,600 C
From previous readings on the topic, the traditional problem with blast furnace reduction using coke is that the resulting iron is normally "pig iron", having way too much carbon. 3.5-4.5% carbon. Generally, too brittle to use.
Cast Iron has lower carbon content on average, 2-4%.
Wrought iron is made by reheating pig iron and essentially beating the carbon out of it. 0.8%.
Steels are normally under 2.1% carbon. Low carbon steels can be under 0.05%
When you make iron using hydrogen reduction methods, you get very close to 0% carbon. If you need more carbon, tossing some pig iron into the mix isn't difficult, or just add only the alloying amount necessary in coke or even purified charcoal if you want to be "renewable".
Re: (Score:3)
We don't beat iron nowadays to get carbon out of it. We push oxygen into molten iron so that oxygen combines with carbon and leaves the process as CO or CO2 gasses.
Problem with the electrochemical process is, that the end result is iron, but what we really need is steel. So we need to get carbon into it. And currently this process requires melting of the iron. So this process does not eliminate the need for melting, but it does remove the need for eliminating extra carbon.
I am a bit curious about how they a
Re: (Score:2)
Removing most of the carbon is done in open air furnaces most commonly, yes.
But as a result, you can end up having to melt the iron 2-3 times. First they make pig iron, then they remove the excess carbon, then they finally form it into the final product.
I'm sure there are processes that do it all in one step, but from reading, it's still commonly done in multiple steps with the metal allowed to cool between steps.
Indeed, with some processes they regularly overshoot on carbon removal, and thus need to add i
Re: (Score:2)
Hybrit (Score:2)
H2 Green Steel will be a large-scale steel producer based on a fossil-free manufacturing process targeting large European OEMs. ... The project includes a giga-scale green hydrogen plant as an integrated part of the steel production facility. Production will begin in 2025 and by 2030, H2 Green Steel will have annual production capacity of five million tons of high-quality steel.
- https://stegra.com/news-and-st... [stegra.com]
It is based on Hybrit, world’s first fossil-free steel production, completed in 2020. It used hydrogen, which is split from water in electrolysis.
Re: (Score:2)
The complete Hybrit should be completed 2026, and if successful could reduce Sweden's CO2 emissions by about 10 percent.
Trump will not like this (Score:2)
surface area (Score:3)
"The porous nanoparticles had much more surface area for the reaction to take place, making the reaction run faster", which makes sense. But this presumably means the iron ore has to be milled down to a finely pulverized dust in order to be appropriate feedstock for their reactor. That's energy-intensive, and I am curious to know what the post-processing steps are once you have your iron nanoparticles (plus whatever leftover waste materials) in solution.
Re: (Score:2)
Fortunately, iron ore is mostly ferrous oxide, which is actually very brittle. Consider the energy demands of heating it up to ~1600C. Compared to that, running it through a few crushing machines would be cheap.
What might be more expensive is that they're looking at using specific forms of iron oxide - FeO, Fe2O3, Fe3O4, etc... Separating those would add expense as well.
A process you can chuck any form of iron oxide into and get acceptable results would be superior. Even if you have to add computerized
Re: (Score:2)
Interesting! Thanks for that info.
Chlorine gas... (Score:2)
Re: (Score:2)
We do enough bulk processing of chlorine and lye that I suspect that answers to that part are already known.
Re: (Score:2)
In the U.S.? Guessing ... (Score:3)
Is There a Greener Way to Produce Iron?
Probably not for another 3.75 years. Unless it can be done with "beautiful, clean" coal. (*sigh*)
move the whole works (Score:2)
Re: (Score:3)
to an active volcano like Hawaii since it is already hot enough to melt iron and iron ore
It actually is not! Iron smelting needs temperatures above 1500C, while lava tops out at around 1200C.
Is the proces interruptible? (Score:2)
I ask if the process is interruptible because then it could be a good use for solar energy. Process the iron ore when the sun is up and electricity is cheap, and shutdown when it's not.
You'll need a relatively minimal amount of battery/storage to keep the lights on at night, but not so much as trying to run 7/24.