[HN Gopher] Making Steel with Electricity
___________________________________________________________________
Making Steel with Electricity
Author : hannob
Score : 126 points
Date : 2023-03-25 07:50 UTC (15 hours ago)
(HTM) web link (industrydecarbonization.com)
(TXT) w3m dump (industrydecarbonization.com)
| pjc50 wrote:
| A bit of digging found what I think is the right technical data
| for the "siderwin" process based on "ulcowin":
| https://energy.nl/media/data/Ulcowin-Technology-Factsheet_08...
|
| A couple of other side features to raise the feasibility: using
| waste as input "the most promising material tested was mill
| scale, a waste product from steel processing" and "Part of the
| Siderwin concept is the idea that the technology can be used as a
| flexibility option in the electricity market."
|
| (i.e. get demand-flexibility payments from being able to turn off
| a large electricity sink easily)
| londons_explore wrote:
| Mill scale is easily recycled in blast furnaces or direct
| reduction furnaces today... It isn't a way to turn a useless
| waste product into something valuable that it sounds like.
| ZeroGravitas wrote:
| The point is to reduce carbon emissions. If there's something
| that is currently being done with carbon outputs, than can be
| done without, then that's a good thing.
| photochemsyn wrote:
| As far as fossil-fuel-free steel goes, this technology is a
| competitor to direct hydrogen reduction. A side-by-side
| comparison would be interesting (i.e. is it cheaper to use
| electricity to make hydrogen to feed into DHR, or just use the
| electricity directly in this manner?):
|
| https://industrydecarbonization.com/news/the-path-to-green-s...
| BiteCode_dev wrote:
| That's really a good field for research right now, because like
| Jancovici notes in his conf
| (https://www.youtube.com/watch?v=KtQBPhKSWu0&list=PLMDQXkItOZ...)
| that we currently price renewable energy in a world where oil is
| abundant.
|
| But once you have to create your wind turbine, solar panels and
| battery with electricity from wind turbines and solar panels, the
| price gets very different.
| u320 wrote:
| Yes it gets more expensive.
| ZeroGravitas wrote:
| How does that add up if he's a proponent of replacing fossil
| fuels with nuclear power?
|
| Won't that get more expensive too?
|
| He's a weird one, as he's generally on board with consensus
| climate change, but he's always had a bee in his bonnet about
| renewables, making lots of claims that haven't came true.
|
| Could we live as today with just renewable energy? (2005)
|
| https://jancovici.com/en/energy-transition/renewables/could-...
| BiteCode_dev wrote:
| > How does that add up if he's a proponent of replacing
| fossil fuels with nuclear power?
|
| > Won't that get more expensive too?
|
| Yes, that's the whole point of the conference. Fossil fuels
| are magical. And at some point, we won't have them anymore.
|
| > He's a weird one, as he's generally on board with consensus
| climate change, but he's always had a bee in his bonnet about
| renewables, making lots of claims that haven't came true.
|
| Jancovici doens't make timed predictions, so I can't see how
| this can be true. A makes statements about how things are,
| starting from first principles.
|
| The only thing he did insist on some time period was the fact
| we will cross the +2Cdeg, at some point in the next decades.
|
| We are well on track for that.
| zeristor wrote:
| My understanding is that Donald Safeway was investigating (2005)
| this as a way of producing metals in space where one can't really
| vent gases into the local atmosphere, or have copious amounts of
| carbon for reduction:
|
| https://www.nasa.gov/sites/default/files/atoms/files/sadoway...
|
| I could be wrong, but couldn't this be counted as one of the
| benefits for NASA and research into space?
| hannob wrote:
| Sadoway is one of the founders of Boston Metal. Boston Metal is
| mentioned later in the article. It is also an iron oxide
| electrolysis technology, but a quite different one (high
| temperature vs. low temperature).
| willis936 wrote:
| I was first introduced to many real industrial concepts through a
| minecraft mod. While not perfect, it did a decent job of exposing
| the player to system dynamics, growth maximization, and real
| technologies.
|
| https://ftb.fandom.com/wiki/Electric_Blast_Furnace_(GregTech...
|
| https://ftb.fandom.com/wiki/Electrolyzer_(GregTech_5)
|
| https://ftb.fandom.com/wiki/Arc_Furnace_(GregTech_5)
| sandworm101 wrote:
| An I was introduced to the principals of alchemy vie the EE
| minecraft mod. Then I learned to plug the alchemy blocks into
| the more industrial mods to prototype some new physics that my
| current startup is currently pitching to people looking to re-
| invest their crypto profits.
|
| https://technicpack.fandom.com/wiki/Category:Equivalent_Exch...
| jimmcslim wrote:
| Meanwhile here in Australia many of us are under the impression
| that while we may run out of buyers for our thermal coal we will
| still have a market for our metallurgical coal... "the lucky
| country" indeed
| anonylizard wrote:
| You know Australia has the highest % of power generated by
| solar of any country?
|
| You know Australia is the biggest lithium exporter? You know
| Australia has copper, rare earths, all required for renewable
| energy?
|
| You know Australia also exports the most IRON, a necessary
| ingredient for steel, right?
|
| Where does this delusion that Australia isn't lucky come from?
| ZeroGravitas wrote:
| Well, one unlucky aspect is the lack of any succesful
| politician that can absorb that widely available info and
| combine it to make Australia into an exporter of high value,
| green products from higher up the supply chain.
|
| Bit of a "resource curse" thing at the moment, where you can
| dig up the wealth and ship it out the country without
| necessarily enriching the wider population as much as you'd
| think.
| alwayslikethis wrote:
| The same also goes for Russia. Despite exporting tons of
| fossil fuels their own electric grid is relatively green
| mostly due to nuclear power. They also are a major exporter
| of nuclear tech, which was not sanctioned at all.
| mkj wrote:
| I'm not sure the iron ore mining companies themselves are
| following that thought train. As a recent example
| https://www.afr.com/companies/mining/fortescue-lab-succeeds-...
| femto wrote:
| Others aren't under that impression though:
|
| https://www.pv-magazine-australia.com/2022/02/23/australias-...
|
| It's an opportunity for Australia. We have the iron ore and we
| have the solar energy to make electricity and hydrogen. If the
| world is going have to rebuild its steel making capacity it's a
| chance to capture some of that.
| 462436347 wrote:
| Over 70% of steel produced in the US is already produced from
| scrap and electricity with Electric Arc Furnances (EAFs):
|
| https://www.steel.org/steel-technology/steel-production/
| londons_explore wrote:
| This demonstrates that the tech is near to being usable at scale.
|
| The thing that doesn't add up is the price... While coal is still
| usable as an energy source for making steel, it doesn't make
| sense to use electricity.
|
| And if one country outlaws using coal for steelmaking, then
| steelmakers will just move to another country - steelmaking is
| ferociously competitive, and lots of countries subsidise
| steelmaking because it is strategically important.
|
| This tech will remain on the sidelines for 'green' projects only
| until there is some kind of worldwide carbon tax/cap/quota
| system.
| awestroke wrote:
| There is massive investment happening in green steel
| production. There is a high demand for green steel from car
| manufacturers among others.
|
| It's easy to dismiss anything out of ignorance, but it only
| amounts to misinformation
| londons_explore wrote:
| Car manufacturers at the moment are happy with "100% recycled
| with carbon free processes" for their steel.
|
| That means you take scrap steel, put it in an electric arc
| furnace, and power that furnace with matching wind/solar
| contracts.
|
| So far, carmaking uses less steel than comes into recycling
| plants, so it hasn't really caused any change in the market.
| Danieru wrote:
| Are you basing this on real knowledge or a guess?
|
| My understanding, from when I lightly researched Japan
| Steel as a stock, was that car makers want fresh steel with
| higher guaranteed performance. Thus they can use less steel
| and reduce weight.
|
| Since vehicles are mobile the reduced weight will have a
| much bigger carbon reduction than from using recycled
| steel.
| steve76 wrote:
| [dead]
| _trampeltier wrote:
| We make welded steel tubes primary for car industry, and
| as far I know, we also use just "new" steel. Still, since
| 2 years or so, in all our mail signatures is something
| about an green steel award we won.
|
| But they just anounced, our factory will be closed by end
| of 2023.
| jillesvangurp wrote:
| Actually cost is why companies are doing research into things
| like this. Carbon emissions are a problem for heavy industries
| in the sense that it will raise their cost and this is
| something they have to address mid to long term.
|
| Meanwhile electricity prices are not a constant and trending
| down. It might be too expensive now but at some point it might
| actually become the cheaper option if cost continues to drop.
| Also, large energy users, like steel plants, would probably end
| up investing in their own energy generation. Wind, solar, maybe
| even nuclear. That turns electricity from a variable cost into
| a fixed cost for them. So, it's not as clear cut that
| electrifying their processes is long term more expensive. It
| might actually turn around and become the cheaper option.
| Carbon taxes of course might make this attractive sooner.
|
| But even if it were more expensive, another reason for
| investing in de-carbonizing steel would be that there is
| actually a growing demand for companies to source their
| materials from companies that have lower carbon emissions.
| Steel is used by a lot of companies and those companies too are
| looking to clean up their supply lines.
|
| And of course because some companies are researching and trying
| different options here, other companies now need to worry about
| having a plan when their competitors start producing cleaner
| and cheaper steel.
|
| All good reasons for companies to be investing in this now
| rather than in 30 years.
| ethbr0 wrote:
| My naive impression is that heavy industry is (and has been)
| doing a lot of research into aligning their processes with
| more intermittent future energy characteristics.
|
| I.e. moving from a "we want to run the plant at optimal
| efficiency, damn the load pattern" to "we want to be able to
| optimize by following energy costs, even if that means we
| need to idle sometimes"
|
| Processes were very well optimized for the former, hence the
| greenfield for research into the latter.
| fbdab103 wrote:
| >even if that means we need to idle sometimes
|
| Is that even possible? For a huge industrial process like a
| steel mill, I think the capital and operational costs are
| so massive you want to run them continuously. Even "turning
| the plant on" could take many hours to get everything to
| temperature and stable.
| ethbr0 wrote:
| That's where the temperature requirements come in. Afaik,
| they're the prime driver of intermittent-tolerance.
| hectormalot wrote:
| Correct. This is a place where regulation could play a role if
| the market is large enough. For example: If the Netherlands
| would prohibit coal for steelmaking, it would just bankrupt the
| 1 steel mill they have. If however, the EU would prohibit coal
| for steelmaking, _and_ introduce a carbon tariff/tax on
| imported steel that was made with coal, it would be a
| significant enough market for companies to still compete for.
|
| It would likely kill the export market for basic steel from the
| EU, as well as raise steel prices across the continent. Long
| term benefit might be that the EU could position itself as a
| technological leader on coal-free steel.
|
| No easy options I suppose.
| fwungy wrote:
| China and India are going to consume any excess fossils at
| decreased costs. Decarbonization is tricky.
|
| We should be thinking more about next gen nuclear and
| mitigation strategies.
| ben_w wrote:
| This is probably a dumb question but:
|
| Given how cheap steel appears to be, would it cause any
| significant damage _to the rest of the economy_ if steel
| prices went up because of this?
| ZeroGravitas wrote:
| This is similar to carbon taxes for airplane fuel. From all
| the fuss you'd assume plane ticket prices would be tripling
| or something, but some estimates are like 8% total price
| increases, since you still have to pay pilots and ground
| staff etc. so fuel is a major cost, but not the only cost.
| throwaway4aday wrote:
| Someone else mentioned that prices in general would go up,
| this is correct but there is also another factor. Steel is
| the primary material used to build manufacturing equipment
| and there aren't any good replacements when you need
| something big, heavy and cheap enough to finance that can
| be used to mass produce other goods. This equipment has to
| be durable, have well known properties and you need to be
| able to make it using existing machine tools and processes.
| So if steel becomes much more expensive not only will
| _everything_ become a lot more expensive, you will also
| negatively impact the creation of new businesses and
| innovation in manufacturing.
|
| This is one of the major second order effects that always
| springs to mind when people just float the idea of
| increasing the cost of some material that produces CO2 as a
| byproduct as if just pulling a lever or adding a tax will
| solve the problem. The economy is a giant Jenga tower where
| all of the lower blocks are fossil fuel based processes. We
| sit way up on top where we can't see the bottom of the
| tower and we think "wow look at all this new stuff we've
| made, we sure are great! We should get rid of all that old
| junk so we can build more new stuff up here!" and maybe you
| can knock out a few of the pieces on the bottom without
| causing a disaster but eventually if you take out enough of
| them the whole thing will come crashing down.
|
| If you want to build a carbon free economy then you need to
| start a new tower and you need to solve all of the
| fundamental problems in a new way with new technology that
| doesn't use fossil fuels and it needs to be as cheap or
| cheaper than what we can do now. That's a monumental task.
| And no, you can't knock over the first tower before
| starting the new one unless you want billions of people to
| die, most likely including you as well.
| zopa wrote:
| > The economy is a giant Jenga tower [...]
|
| A Jenga tower is in unstable equilibrium. Push it a
| little bit away from its resting configuration and it
| collapses.
|
| The economy is in stable equilibrium, mostly, more or
| less. Push it by increasing the price of some commodity,
| which happens all the time, and buyers look for
| alternatives and efficiencies, which dampens the effect
| of the push. In all likelihood things settle in a new
| equilibrium not far at all from the first.
|
| It's a much more resilient system than you're giving it
| credit for. Totally different dynamics than the party
| game.
| vegetablepotpie wrote:
| Right, and that CO2 will also impose a cost that we'll
| also have to pay for. Higher global temperatures means
| fewer glaciers. Nearly two billion people in the world
| depend on glacial run off for their water [1], which a
| lot of will be gone in a few decades.
|
| Rising global temperatures will also mean melting ice and
| rising sea levels. Low level agricultural areas, such as
| those in Southeast Asia will, will see the ocean encroach
| 30-40 kilometers onto productive rice paddies with just a
| few feet of sea level rise [2].
|
| It might be fine if these people just move, but we're
| talking about displacing hundreds of millions to
| billions. Migrations like those of Syrians moving into
| Europe will seem small by comparison.
|
| I'm not going to mention the retarding economic effects
| of more stable regions having many more hotter days, or
| the impacts of more erratic weather due to arctic
| amplification and a more erratic jet stream. We may have
| to move or build new equipment someplace else.
|
| All of this means that we will have to build a new tower
| anyways, but we'll have to do it with less resources,
| less time, and on a table that's shaking constantly.
|
| Perhaps putting a tax or price on carbon will retard
| economic advancement, but so will unchecked climate
| change. The benefit of taxing carbon is that we don't
| have governments directing how to decarbonize. Businesses
| can still innovate to be competitive, we will be pricing
| in an externality that we'll just pay for in other ways,
| at a higher price, later on.
|
| [1] https://www.washingtonpost.com/climate-
| environment/2023/01/0...
|
| [2] https://vlscop.vermontlaw.edu/2019/11/07/sea-level-
| rise-food...
| marcosdumay wrote:
| If you are concerned about the costs of raising CO2, I
| would suggest looking first at the places where it can be
| cut with the smallest investment and smallest economical
| impact that add to more than 80% of the CO2 emissions,
| like transportation and electricity generation.
|
| The places that require the highest investment, could
| completely ruin the life of most people, and add up to a
| single digit percentage of the problem (or less) are
| better left to research.
|
| Carbon taxes would indeed help. More because it will let
| people do the calculation above than for any other
| reason. But trying to hijack a discussion about carbon
| substitution in steel making into a "we must act because
| the sky is falling" is in very bad taste.
| [deleted]
| HPsquared wrote:
| Diamond/water paradox comes to mind.
| apexalpha wrote:
| >Given how cheap steel appears to be, would it cause any
| significant damage to the rest of the economy if steel
| prices went up because of this?
|
| Yes but most likely way less than the damage of climate
| change.
| londons_explore wrote:
| The price of steel feeds into the price of lots of other
| things. Cars, buildings, bridges, etc.
|
| If steel is more expensive, then the quality of life of
| most people will go down, even if people don't walk into
| walmart and think "today I'll buy some steel".
| ben_w wrote:
| Feeds in yes, but how significant is it as an input cost?
| Would doubling the price of steel increase general
| inflation 0.1% or 10%?
|
| (Even as a vague number; economics is never going to be
| my job).
| roenxi wrote:
| In theory, either the price will go up so much that
| people use less steel or other goods will stop being
| produced to free up more energy for steel production so
| that it stays level. Possibly some combination. If
| governments make steel production harder there aren't a
| lot of other ways the story would end. It is impossible
| for the process to be less efficient without prices
| moving enough to change behaviour. Something has to give.
| mschuster91 wrote:
| > This tech will remain on the sidelines for 'green' projects
| only until there is some kind of worldwide carbon tax/cap/quota
| system.
|
| Doesn't need to be worldwide. The EU and US are large enough
| markets that can put up import tariffs on carbon.
|
| In any case, the production of coal is going to go down rather
| sooner than later... steelmaking should prepare for this.
| nonethewiser wrote:
| The article says the steel industry accounts for 7% of all
| emissions, which is quite a bit. Did not realize that.
|
| How much of the steel industry is in China? My impression was a
| very large percentage of it. I wonder if this process would be
| utilized there. The game there seems to be the cheapest possible
| steel... not sure this fits into that.
| hannob wrote:
| It's actually even worse. The _direct_ emissions are 7%, the
| whole are 12%. That includes things like the footprint
| electricity that steelmaking uses.
|
| I used the lower 7% number in that article, because that's the
| emissions one talks about when tackling process / blast furnace
| emissions, so I thought using the higher number would be
| misleading in that context. (I have mentioned both numbers in
| an earlier text that is also linked:
| https://industrydecarbonization.com/news/the-path-to-green-s...
| )
| c54 wrote:
| Part of the story is that solar electricity will soon become
| (indeed, in many places already is) cheaper than coal or
| natural gas.
|
| China in particular depends on long fragile trade routes from
| the Middle East for crude oil, and is already the world's
| largest producer of solar panels.
|
| Technology like this will get to enjoy the plunging cost of
| solar and wind power.
| ethbr0 wrote:
| Was curious about the currently installed amounts:
| https://www.visualcapitalist.com/mapped-solar-power-by-
| count... (2021)
|
| You can definitely see a divergence between countries that
| have made it a priority and those that haven't, even per
| capita.
|
| Now that we've had larger deployments for awhile, are there
| any good number on capacity deterioration over time?
|
| Curious what the effective install longevity is.
| pjc50 wrote:
| https://news.energysage.com/longevity-of-solar/ : 0.7
| percent degradation per year. That works out at over 80%
| after 25 years. The inverters need slightly more frequent
| replacement.
|
| The compounding effects on this are going to be dramatic.
| Everyone who borrowed money at sub-5% rates and then saw
| retail electricity going up by 50% made a great decision.
| ethbr0 wrote:
| My thinking, isn't the effective end state that power
| stabilizes at much lower and without capacity cap solar
| rates?
|
| Previously, worldwide supply expansion = increasing fuel
| costs in the global market
|
| In a post-fuel / solar world, you can keep increasing
| supply capacity as long as you want. Which would upend a
| lot of assumptions about power. E.g. free or negative
| power cost at peak supply times, simply because people
| keep building capacity
| danhor wrote:
| > free or negative power cost at peak supply times,
|
| The electricity price already turns negative in quite a
| few countries with larger shares of renewables at peak
| times, but isn't really being exploited right now due to
| the high capital cost and low usage for most things that
| need electricity.
| ethbr0 wrote:
| I guess my perspective is "When will people stop building
| solar capacity?"
|
| Which is another way of asking "When will people stop
| consuming more power?"
|
| Previously, we had finite energy resources that were
| limited by the fuel (oil, coal, gas) or regulation
| (nuclear).
|
| Suddenly, there is no limit. You _could_ build as much
| solar as you had panels + installers for.
|
| Which really turns future energy on its head. Why not
| build more forever? And if there's excess, build more
| energy consumptive industry...
| tonmoy wrote:
| Steel and concrete account for a large percentage of carbon
| emissions and we don't really have any viable technology to
| replace this in the near future.
| denton-scratch wrote:
| > In the Siderwin plant, the iron oxide is dissolved in a
| solution between a nickel anode and a carbon cathode.
|
| Dissolved in what solution? That's got to be an aggressive
| solvent, so what is the waste this process produces?
| bell-cot wrote:
| > ... In other words: Pure electricity is used to split iron
| oxide into its elements. ...
|
| > ...the iron oxide is dissolved in a solution between a nickel
| anode and a carbon cathode. ...
|
| > ...operates on relatively low temperatures of around 110 degC.
| ...
|
| IANACE (Not A Chemical Engineer), but dissolving iron oxide at
| 110 degC sounds to me like they'll be using some fairly nasty
| chemicals, at scale. Which chemicals will have their own
| environmental & safety issues, etc.
| burnished wrote:
| Sodium hydroxide in water.
| bell-cot wrote:
| So pretty harmless ( _in context_ ) itself. Might you have
| any sense for the waste product stream (from the NaOH and
| impurities in the real-world iron ore), and its major issues?
| pjc50 wrote:
| NaOH is the classic drain cleaner. You wouldn't want to
| just dump it in the river, but it's dilutable/neutralizable
| to harmlessness. Handily, it also reacts (slowly) with CO2
| directly out of the air to harmless sodium carbonate.
|
| https://www.sciencedirect.com/science/article/pii/S24056561
| 1...
|
| The rest of the waste stream is just slag. That's just
| dumped in big piles in the open air
| https://www.usgs.gov/news/science-snippet/slag-what-it-good
| , although occasionally someone proposes going through it
| again for different minerals such as rare earths.
| riedel wrote:
| The headline is a bit misleading since 42% of steel production
| [1] in Europe is already done using an electric arc furnace (i.e.
| electricity) . However, this is mostly recycling [2]
|
| [1]
| http://www.eurofer.org/201605-ESF.pdf?wtd=YC9cwLHyOWxX6JJD&r...
|
| [2]
| https://wikiless.tiekoetter.com/wiki/Electric_arc_furnace?la...
| londons_explore wrote:
| In my view, the steel industry deliberately confuses arc
| furnaces (mostly used for recycling steel - effectively just
| melting it down) with making new steel in blast furnaces.
|
| This lets them do things like claim "steel made in USA" when in
| fact the steel was made in China, then brought to the USA,
| melted in an arc furnace, and suddenly it's "made in USA"!
|
| I suspect there are people chucking brand new steel into an arc
| furnace simply to change its origin country, and to take
| government subsidies for setting up new 'steel factories'. It
| also conveniently works around steel import tariffs - because
| you actually import 'scrap' steel, tariff free.
| simplotek wrote:
| > (...) 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".
| ethbr0 wrote:
| 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.
| akiselev wrote:
| 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!
| ethbr0 wrote:
| Is that lifecycle or at-plant to output?
|
| My impression was most of the recycling energy inputs
| were in collection, sorting, and shipping.
| akiselev wrote:
| 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.
| ethbr0 wrote:
| Do you have any links? Would love to learn more.
| akiselev wrote:
| 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 _kilo_ joules 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_tr
| ansport
| londons_explore wrote:
| 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.
| akiselev wrote:
| 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!
| TheSoftwareGuy wrote:
| 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
| credit_guy wrote:
| Does this actually happen, or it's just a hypothetical?
| (in other words, do you have some links?)
| simplotek wrote:
| > 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.
| simplotek wrote:
| > 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.
| Animats wrote:
| That's about right for the US, too. Once a country is
| developed, the amount of steel in active use seems to be
| roughly constant. It's easy to extract from trash and
| recycling. That's how Nucor, which is mostly a recycler, became
| the US's largest steel company. (15th in the world, though. The
| top 14 are in China, Japan, S. Korea, and India. Except for
| ArcelorMittal, which is nominally in Luxembourg but is a
| holding company which buys up old steel mills and restarts
| them.)
| mannykannot wrote:
| This is actually about extracting iron from ores and other
| sources of its oxide, as opposed to making steel from metallic
| iron and scrap steel.
| photochemsyn wrote:
| A direct reduction system (whether powered by hydrogen or this
| electrolysis method) would be upstream of the electric arc
| furnace, see this graphic:
|
| https://www.steel.org/steel-technology/steel-production/
|
| It's iron ore -> direct reduction (iron) -> electric arc
| (steel) with carbon being added to the iron in the furnace.
| This is a replacement for the older pipeline of iron ore ->
| blast furnace -> basic oxygen furnace.
| ginko wrote:
| Those still add coke or coal as a reducing agent though so it's
| not carbon neutral.
| scythe wrote:
| The key to allowing this process to be performed at low
| temperature appears to be the use of sodium hydroxide as the
| electrolyte:
|
| https://iopscience.iop.org/article/10.1149/MA2020-02191562mt...
|
| The more well-known approach, performed by Boston Metal which the
| article mentions, was to use molten iron oxide.
|
| I would figure the major question is whether the cost and
| handling difficulties of NaOH can be overcome. Google shows a
| bulk price of around $500/ton for NaOH, though its price has
| spiked recently. This is roughly double the price of pig iron
| (the first reduction product). So to make this process
| economical, you need to do a good job of not contaminating (hence
| replacing) your electrolyte. That's probably why they needed to
| work with particular grades of iron oxide. NaOH is contaminated
| by such mundane things as carbon dioxide, silicates, alumina,
| etc. Hopefully they can figure this out.
| pjc50 wrote:
| > NaOH is contaminated by such mundane things as carbon
| dioxide, silicates, alumina
|
| .. all of which you might find in iron ore, unfortunately. I
| guess that's why they're using it to recycle rather than from
| ores.
| ChrisMarshallNY wrote:
| The one thing that raised an eyebrow for me, is the production of
| pure oxygen, as a by-product.
|
| Pure oxygen is dangerous stuff.
|
| Otherwise, cool. Of course, whenever we electrify something,
| we're just kicking the "carbon cost" down the road, and the means
| of electrical production become a focus.
|
| That said, if we can distill energy to centralized electrical
| plants, we can apply fairly massive carbon mitigation, at a
| single point.
| jillesvangurp wrote:
| We're talking about steel plants here. They are dealing with a
| lot of dangerous stuff there. Like tonnes of extremely hot
| metal in liquid form. A little bit of oxygen is not going to be
| something that is much of a concern relative to that.
| hutzlibu wrote:
| "A little bit of oxygen is not going to be something that is
| much of a concern relative to that."
|
| It is a concern, exactly because there are so many other hot
| and dangerous things around in steel production. Blow some
| oxygen on a fire and see what happens...
| WJW wrote:
| This would be a way better argument if modern steelmaking
| processes didn't quite literally involve blowing oxygen
| through the molten steel. :)
|
| (They do this in order to reduce the carbon content. See
| https://en.wikipedia.org/wiki/Basic_oxygen_steelmaking for
| details if you want to know more, it has a fascinating
| history)
| MisterTea wrote:
| I never get the hand waving types. I think knowing the
| danger of something is the only bit of knowledge they
| have on a subject. So prove they understand it they go
| about lecturing people on how dangerous it is instead of
| actually understanding the subject. Otherwise they would
| understand that while dangerous in an uncontrolled
| environment we understand how to mitigate danger and
| design/build/use something responsibly. This is why we
| cant have nice things. Know-it-all danger rangers just
| ruin it with paranoia and ignorance.
| hutzlibu wrote:
| "This would be a way better argument if modern
| steelmaking processes didn't quite literally involve
| blowing oxygen through the molten steel"
|
| But molten steel is not a fire. But you know what will be
| a fire, at certain oxygen levels? The human body for
| example, despite that it is made of 80% water.
|
| So sure, the steel makers will be able to handle it. But
| only because they take this stuff seriously.
| WJW wrote:
| Pure oxygen is quite reactive, but in the grand scheme of
| industrial chemicals it is relatively benign. You could just
| mix it with outside air using a big fan, if there are no better
| uses found for it. Oxygen has a huge amount of industrial uses
| though, so depending on the purity it might even be worthwhile
| to capture the waste stream and sell it.
| DeathArrow wrote:
| What about the costs of the process? How do they compare with the
| classical process?
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