9 ms·

Metal Without Mining

80 points by sctgrhm 4y ago

proee 4y ago
Isn't Magnesium highly flammable/explosive? How do you protect parts made from this metal?
- TheDudeMan 4y ago
  https://en.wikipedia.org/wiki/Magnesium_wheels#Common_issues https://en.wikipedia.org/wiki/Magnesium_wheels#Common_issues
  - omnicognate 4y ago
    I've seen this assurance before that magnesium flammability isn't a practical concern, usually just saying fires are "rare", but never any real information as to why. From that link it sounds like there are alloys that maybe preserve the desirable properties of the metal but aren't as flammable as elemental magnesium. Anybody know more about that? Why it works? How well?
    - nwiswell 4y ago
      > From that link it sounds like there are alloys that maybe preserve the desirable properties of the metal but aren't as flammable as elemental magnesium. Anybody know more about that? Why it works? How well? It's been a long time since my metallurgy courses, but in general there are three major ways that properties are altered at the mesoscale due to alloying: 1) a different solid phase of the dominant metal is formed due to the solid solution of the minor alloy components 2) covalently bonded compounds are formed between the base metal and minor components ("intermetallics") 3) the microstructure is changed (think e.g. alternating layers of intermetallics and metal grains) Because the thermodynamic driving forces are basically identical regardless of the solid phase, #1 is probably not helpful here (also, it's flammable in liquid form -- I checked). But the intermetallics may not be flammable. So then your fire resistance comes from a combination of #2 and #3: if you form a lamellar structure of the non-flammable intermetallics separating the regions of the flammable majority phase, then that may produce macroscopic fire resistance. I can't comment on how well it works, of course. But if you have some "secret sauce", maybe a sintering process or special heat treatment, you might be able to manipulate the lamellar structure in a desirable way and end up with a very fire-resistant alloy. The catch is that this might be pretty expensive. ETA: because this fire resistance is dependent on the microstructure and presence of intermetallics, if the alloy is heated back to a temperature where those intermetallics dissolve into solid solution (or, obviously, if it melts), then it's going to be flammable again. So my educated guess is that while you can't actually light these special alloys on fire, if you were to throw some into an ongoing inferno, it would heat up and then combust. So in an otherwise flammable environment cough hydrogen airship cough, maybe not the greatest idea.
      - TheDudeMan 4y ago
        Bad conclusion. If your airship has become hot enough to burn magnesium alloy, your airship is already dead (as is whatever it landed on).
        nwiswell 4y ago
        For an airship of the size proposed in that post, I don't think I agree. Presumably there would be some measure of compartmentalization, ventilation, and fire suppression so that even if a portion of the craft was stricken, the entire vessel would not be doomed. But even so, there's going to be a point where there's just too much fuel to keep the fire under control despite best efforts, and the fire-resistant magnesium could certainly contribute to reaching that threshold once you cross a certain temperature. And you cannot simply vent combusting magnesium the way you can vent combusting hydrogen (hypothetically, anyway).
- umvi 4y ago
  Mainly in elemental form. When properly alloyed its explosive/flammable properties can be mitigated.
- 83 4y ago
  Magnesium parts are already in widespread use. The covers you see on the sides of motorcycle engines/transmissions are often magnesium. In solid form the risk is mitigated because there isn't enough surface area for the reaction with oxygen, it's the powder/shavings that are a concern. You can actually weld magnesium parts without it igniting. Reading up on it a little more - it seems with enough heat solid magnesium can start a self-sustaining burn without oxygen. I wish I could find a laymans explanation of the difference between oxygen fueled magnesium powder fire and self sustaining. Must take an awful lot of heat if a welding arc isn't hot enough to cause this. Edit: Also think of steel wool and how well it burns, but a block of steel not so much.
  - forgotusername6 4y ago
    I used to have a flowerpot furnace and cast small objects. I once stumbled upon a car that had been burnt out. The engine block had dripped down the road and I was able to collect some of the melted pieces. It would pop and spit when poked once cast, very different to the aluminium I often used, and I wondered at the time whether it was the magnesium in the block that was doing it.
  - BurningFrog 4y ago
    If the magnesium is not reacting with oxygen, it must react with something else to produce more heat than is put in. I discount the possibility of nuclear reactions :)
  - lazide 4y ago
    Welding arcs definitely can cause magnesium fires. Generally the shielding gas used to protect from oxidation prevents it, but it's easy to screw up. It's a tricky metal to weld because of it. Generally you also need to preheat it so you don't get cracking, which makes it even more of an issue. There is a passivated oxide layer that forms (similar to aluminum) which generally reduces the risk, but if it's compromised (like from cleaning the weld area)....
  - GravitasFailure 4y ago
    Magnesium can't burn without oxygen, but it will happily rip the oxygen out of water and sand, making it exceptionally annoying to put out.
- deleted 4y ago
  [deleted]
- klyrs 4y ago
  Old timers recall the infamous case of the NeXT Cube... https://web.archive.org/web/20000817013818/http://simson.net/photos/hacks/cubefire.html https://web.archive.org/web/20000817013818/http://simson.net...
  - reaperducer 4y ago
    "This is so NeXT," I told Sally. "Everything works great in the tests, then when you try to make it work for real, in the field, nothing works. They build a computer out of magnesium, and it doesn't even burn!"
  - dzuc 4y ago
    https://www.flickr.com/photos/nitroba/albums/72157594435480450 https://www.flickr.com/photos/nitroba/albums/721575944354804...
  - umvi 4y ago
    Wow, that story is a great example of "it's better to ask for forgiveness than permission". Just drive to the desert and burn it, don't waste 100 hours trying to get permission from the state of California to burn it.
    - klyrs 4y ago
      Is it though? They got a bunch of assistance from the folks at Lawrence Livermore, and the photographer was happy to not take pictures of fire in direct sun. Asking permission likely got a much better outcome; the author sounded pretty unprepared to ignite the thing without the help he got.
- dbcurtis 4y ago
  Magnesium metal will burn very violently once it gets going. Among the biggest trouble I got into in high school was when my chem lab partner and I decided it would be entertaining to burn a small piece of magnesium metal. It was rather spectacular, and indeed entertaining. Well worth the Very Stern Lecture. Some aircraft historian will have to fill in the gaps in this story (what aircraft?), but back during the Korean War era, the USAF had a multi-engine piston-driven plane that was either a transport or a cargo aircraft -- not sure which, but the engine blocks were magnesium to save weight. One of the biggest brown-factor events that you could have was an engine fire, because once it got started, your day was going in a bad direction very fast. A friend's dad was pilot-in-command of a plane fresh out of maintenance. An engine caught fire on climb out. He ordered the rest of the crew to hit the silk and he tried to get back to the field. He did, but the landing was not pretty, and he suffered a nasty leg injury. No more combat rating for him, and he finished is USAF career flying transports, and later had a career as a commercial airline pilot. He was luck to survive that engine fire event.
  - deleted 4y ago
    [deleted]
- londons_explore 4y ago
  Oddly, tiny chunks/slivers of magnesium are very flammable, but a big chunk of it is pretty much impossible to set fire to. Source: I was disappointed to buy a few lbs of magnesium to burn on the bonfire, only to find that chucking a lump of it on the bonfire doesn't even burn. Shavings did though.
not-my-account 4y ago
Magnesium reacts with water, so I assume that another metal would be used to make some stable alloy?
- deleted 4y ago
  [deleted]
- s0rce 4y ago
  Magnesium is protected by a passive oxide layer and isn't particularly water reactive (unlike sodium and potassium which will react with water more readily). You can toss a chunk of magnesium and water and nothing happens.
v8xi 4y ago
I love ideas around extracting minerals from seawater since there is just so much. e.g. estimated 4.5B tons of uranium in seawater, ~1000x higher than land sources. Pretty much everything is dissolved in there, but the energy requirements are insane
amiga-workbench 4y ago
There used to be a plant near me which did something similar (extract magnesium oxide from seawater), it finally got demolished in 2012 and they're building houses on the land. https://hhtandn.org/venues/287/steetley https://hhtandn.org/venues/287/steetley https://co-curate.ncl.ac.uk/hartlepool-magnesia-works/ https://co-curate.ncl.ac.uk/hartlepool-magnesia-works/
macinjosh 4y ago
Ok, hear me out. If stripping these minerals from the land had a negative impact wouldn’t stripping them from ocean water (which is the medium containing life, unlike ore) may also have negative consequences?? Seems to me like a pretty drastic alteration of ocean water chemistry in the long term. What if animal biology expects the magnesium to be available?
- danans 4y ago
  That's true if the minerals extracted are consumed completely. Metals however, are often the most recyclable materials we use, because unlike carbon-based materials like plastics, metals often have useful properties in their elemental state, or as alloys that can be melted down and reused without the loss of those properties or of much material. Most aluminum, for example is recycled, because the cost of recycling it is lower than the cost of mining new material.
  - throwaway4aday 4y ago
    The concern isn't that we'll completely deplete the ocean, that would be a monumental task. The worry is about what happens at the "mining" sites. Those are going to be in continuous operation for a long time.
    - danans 4y ago
      Assuming that the magnesium is coming from the seawater and not the seabed, would we not expect currents to re-balance the concentration? In fact, we would design the facilities to ensure that it happened.
- jillesvangurp 4y ago
  Eh no. Oceans are big. Really big. Unbelievably big even. We're talking about filtering tiny fractions of ocean water, and nowhere close to all of it. Literally a drop in the ocean in comparison. So, no. This is not a serious concern.
  - 4y ago
ChuckMcM 4y ago
If you are wondering "how" they are doing this, I believe this company is the externalization of this research: https://www.innovationnewsnetwork.com/new-method-extract-magnesium-from-seawater/25685/ https://www.innovationnewsnetwork.com/new-method-extract-mag... (Kind of hard to pin down exactly since they don't say a lot about how they are doing it, but a quick check suggests this is the only "new" thing in extracting magnesium recently and Magrathea is a young company[1]) [1] https://www.crunchbase.com/organization/magrathea-metals https://www.crunchbase.com/organization/magrathea-metals
- whatshisface 4y ago
  Externalization? Do you mean commercialization?
  - ChuckMcM 4y ago
    Effectively yes. I tend to think of research to product in two phases, phase one is "externalization" which involves taking something done in the lab and reproducing it in a scalable process, step two is "commercialization" which is to capture market share. I use two phases because each phase captures very different risk profiles relative to the technology.
- avernon 4y ago
  They mention that they are doing electrochemistry. A huge portion of historical magnesium production is from electrolysis, including the only operating plant in the US. Past methods have used lime to precipitate magnesium (Dow) or evaporation ponds to concentrate it (the current Utah plant). Probably the new thing they are doing is using something like Chlor-Alkali to make base that precipitates the magnesium instead of using lime. Then the electrolysis of molten magnesium salts would be similar to products of today. There is some chance they have improvements in these areas, but there are really only so many options. The job descriptions they've posted support this hypothesis. Recently most magnesium comes from China. They mine ore, throw it in a coal-fired furnace along with some reducing agents, then collect pure magnesium vapor. This process is more labor and energy intensive, but has significantly less CAPEX. Works for China. Chlor-alkali is more expensive than lime and the back-end electrolysis is more expensive than thermal reduction. So I'd be skeptical they are going to lower costs without some kind of CAPEX reducing magic for molten salt electrolysis.
speed_spread 4y ago
Of similar interest, magnesium production from accumulated mine tailings : https://alliancemagnesium.com/en/products/primary-magnesium/ https://alliancemagnesium.com/en/products/primary-magnesium/
- thepangolino 4y ago
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stevespang 4y ago
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UberFly 4y ago
That website is really lacking any worthwhile details. Are they just fishing for venture capital at this point?
- EarlKing 4y ago
  Well, you must understand that they only just awoke from a few million years of sleep to discover their entire cleaning staff is dead. Who's going to pick up the bodies? That's what nobody seems to have an answer to...
gdsdfe 4y ago
it looks like somebody's school homework
philipkglass 4y ago
There are two major ways of producing magnesium [1]: 1) Electrolytic production from anhydrous magnesium chloride, similar to the electrolytic production of aluminum. 2) The Pidgeon process, which currently dominates Chinese (and world) magnesium production. It distills magnesium vapor under vacuum from a heated mixture of ferrosilicon and magnesium-calcium oxide (calcined dolomite). The Pidgeon process has a high global warming potential because of the coal used to produce the ferrosilicon input and to heat the retorts. The electrolytic process has a lower global warming potential, especially if using low-carbon electricity, but historically sulfur hexafluoride has been used as a protective cover gas for the metal during electrolytic production. This gas has a staggering global warming potential 23,900 times that of CO2 [2] so incidental leakage of even small quantities can have a high climate impact. The "without mining" part is not novel. Dow Chemical produced electrolytic magnesium from seawater without mining at Freeport, Texas from 1941-1998, until lower cost foreign magnesium made it uneconomical: https://www.chemicalonline.com/doc/dow-to-exit-magnesium-business-0001 https://www.chemicalonline.com/doc/dow-to-exit-magnesium-bus... Reading the company's rather sparse public info, it looks like this is a revival of the same basic kind of process as Dow used. But since it's focused on certifying a low GWP for its magnesium, the company will not use sulfur hexafluoride. ("We’re piloting a new generation of electrolytic production technology that is inherently carbon neutral, removing the need for coal and carbon-intense reagents like FeSi and SF6.") They don't say it directly but they also must be using clean electricity for the electrolysis, otherwise the metal would still be fairly CO2-intensive. Unfortunately, the latest news item from their news page is about a threat to their business: "State of Utah denies US Magnesium’s request to extend canals into the Great Salt Lake threatening shutdown of the only American magnesium producer" https://sltrib.pressreader.com/article/6830844853434424 https://sltrib.pressreader.com/article/6830844853434424 [1] https://ro.uow.edu.au/cgi/viewcontent.cgi?article=2295&context=engpapers https://ro.uow.edu.au/cgi/viewcontent.cgi?article=2295&conte... [2] https://en.wikipedia.org/wiki/Sulfur_hexafluoride#Greenhouse_gas https://en.wikipedia.org/wiki/Sulfur_hexafluoride#Greenhouse...
jacquesm 4y ago
If you're wondering about where the name Magrathea comes from: https://hitchhikers.fandom.com/wiki/Magrathea https://hitchhikers.fandom.com/wiki/Magrathea
- dunham 4y ago
  I knew it was from the book, but I'd forgotten exactly what Magrathea was, so I started reading the article. Halfway through I got a kernel panic (macos 12.6.2 / intel).
  - jacquesm 4y ago
    Probably just some old cyber defense systems taking the occasional potshot to relieve the monotony ;)
    - mrlonglong 4y ago
      Marvin most likely
ummonk 4y ago
It's not "impossible" to decarbonize the production of aluminum without driving up cost, as the page claims. Once green electricity and hydrogen is cheaper than CO2-emitting energy, this will be possible and even profitable.
- tekno45 4y ago
  Isn't new renewable power cheaper than new C02 power?
  - garettmd 4y ago
    From what I understand, it is cheaper. However, that's just with new power. Most of the power available now is from existing installations, making existing fossil fuel power cheaper than any new installations.
  - marcusverus 4y ago
    I've yet to hear about renewables that put out consistent power cheaper than gas. You'll see the occasional article about new solar that's claimed to be cheaper than gas, but they never have sufficient storage to actually stand on their own two feet. The last one that was posted here on HN was claimed to be cheaper than gas, but it only had enough storage to output 1/2 of its daytime production overnight. In other words, it was cheaper than gas... as long as you've got redundant gas plants to provide power overnight. Always read the fine print when folks are pitching "cheap renewables".
  - Taniwha 4y ago
    The Hall–Héroult process (electrolysis of alumina to make aluminium) uses a sacrificial carbon anode - every 2 atoms of Al you produce results in 3 CO2 molecules - so for every kg of Al you make ~2.4 kg of CO2
- hannob 4y ago
  The problem with decarbonizing is not being solved with green electricity and hydrogen. The (direct) emissions come from the carbon anodes that are consumed in the process. They are usually made from petroleum coke, aka they're fossil fuels. Alternatives are being developed, but have a somewhat troubled history. Alcoa announced in the early 2000s that they are only months away from deploying inert anode technology. They're still not there (though still working on it in a project called elysis).
geuis 4y ago
This entire website and company reads like a penny pink sheets stock scam. "Magrathea sells metal using multi-year supply agreements in countries with enforceable contract law. Supply agreements allow our partners to build in magnesium with confidence. We prevent price instability from Chinese trade manipulation so the innovative products of our partners can succeed in the market." There's absolutely no information on the site detailing their tech. Just a lot of buzzwords. Under the News section, it's the typical list headline articles cherry picked to make the company sound better.
- EarlKing 4y ago
  "Greetings to you. This is a recorded announcement as I am afraid we are all out at the moment. The commercial council of Magrathea thanks you for your esteemed visit but regrets that the entire planet is temporairly closed for business. If you would like to leave your name and the address of a planet where you can be contacted kindly speak when you hear the tone... *BEEEEEEEP*."
- marcosdumay 4y ago
  Somehow we should expect them to be able to purify magnesium from brine, and yet not be on the market selling lithium. That's extremely odd. Edit: Turns out that no, it's simpler to separate magnesium and calcium than lithium, even those existing in much smaller amounts. Those metals form many solid ionic compounds, with anions that would keep sodium and lithium soluble.
  - runnerup 4y ago
    The majority of the magnesium used for WW2 explosives was produced from brine near Freeport, TX. (I think? need to double-check this) Edit: During WW2 additional production facilities around the USA were brought online. Before and after WW2, except for a moment during the Korean War, Dow's facility in Freeport, TX was the only producer of magnesium in the USA. It peaked in capacity in the 1970's. There were several other endeavors by other companies to produce magnesium over time with different technologies. Most magnesium production in the USA has been eliminated for economic reasons.
- 4y ago
sbierwagen 4y ago
Brine mining isn't new, of course. Table salt is the canonical example of a metal compound extracted by evaporating brine, but there's a dozen other elements that are harvested at scale for profit from various brines: https://en.wikipedia.org/wiki/Brine_mining https://en.wikipedia.org/wiki/Brine_mining including Magnesium https://en.wikipedia.org/wiki/Brine_mining#Magnesium_and_magnesium_compounds https://en.wikipedia.org/wiki/Brine_mining#Magnesium_and_mag... If you're in the bay area, you've seen a brine mine dozens of times: https://en.wikipedia.org/wiki/San_Francisco_Bay_Salt_Ponds https://en.wikipedia.org/wiki/San_Francisco_Bay_Salt_Ponds
- culi 4y ago
  I've wondered about these salt evaporation ponds a lot. It's the traditional way sea salt has been harvested in Japan from the sea and also in the mountains of the Andes from mountain deposits of salt water. And it is still harvested industrially like that on some islands. The thing I'm really curious about is this is happening on a large enough scale does it begin to affect the amount of precipitation that can occur? I'm wondering if it can be utilized to increase rainfall during times of drought Maybe even long canals to transport the ocean water far inland in very shallow streams that are meant to be evaporated by the sun over time. This uses almost no energy on our part, produces salt, and might possibly help increase rainfall?
  - AndrewDucker 4y ago
    Remembering that water flows downhill, and places a long way inland are likely to be significantly higher than sea level, I'm not sure how feasible digging long canals many miles inland will be. Particularly if they will then fill up with salt.
  - temporary22 4y ago
    Salt kills most plants. Bringing it inland would basically stop agriculture for hundreds of meters surrounding the canal. If it goes into the aquifer it's even worse. Also, inland is usually higher than sea level (where it's lower you get lakes / ponds / swamps, unless it's actively managed), so you would be creating ditches a hundred meters deep if not more. I'm also not sure that local water would increase rainfall, any amount of wind would sweep moisture off immediately. The most it can do is to increase the humidity of the surrounding area when windless.
ctoth 4y ago
I checked Linkedin and couldn't find a Slartibartfast, are we sure this company is legit?
pstuart 4y ago
If this is mining brine, then it would be a perfect pairing with a desalinization plant.

80 points by sctgrhm 4y ago

proee 4y ago

Isn't Magnesium highly flammable/explosive? How do you protect parts made from this metal?

TheDudeMan 4y ago
https://en.wikipedia.org/wiki/Magnesium_wheels#Common_issues https://en.wikipedia.org/wiki/Magnesium_wheels#Common_issues
- omnicognate 4y ago
  I've seen this assurance before that magnesium flammability isn't a practical concern, usually just saying fires are "rare", but never any real information as to why. From that link it sounds like there are alloys that maybe preserve the desirable properties of the metal but aren't as flammable as elemental magnesium. Anybody know more about that? Why it works? How well?
  - nwiswell 4y ago
    > From that link it sounds like there are alloys that maybe preserve the desirable properties of the metal but aren't as flammable as elemental magnesium. Anybody know more about that? Why it works? How well? It's been a long time since my metallurgy courses, but in general there are three major ways that properties are altered at the mesoscale due to alloying: 1) a different solid phase of the dominant metal is formed due to the solid solution of the minor alloy components 2) covalently bonded compounds are formed between the base metal and minor components ("intermetallics") 3) the microstructure is changed (think e.g. alternating layers of intermetallics and metal grains) Because the thermodynamic driving forces are basically identical regardless of the solid phase, #1 is probably not helpful here (also, it's flammable in liquid form -- I checked). But the intermetallics may not be flammable. So then your fire resistance comes from a combination of #2 and #3: if you form a lamellar structure of the non-flammable intermetallics separating the regions of the flammable majority phase, then that may produce macroscopic fire resistance. I can't comment on how well it works, of course. But if you have some "secret sauce", maybe a sintering process or special heat treatment, you might be able to manipulate the lamellar structure in a desirable way and end up with a very fire-resistant alloy. The catch is that this might be pretty expensive. ETA: because this fire resistance is dependent on the microstructure and presence of intermetallics, if the alloy is heated back to a temperature where those intermetallics dissolve into solid solution (or, obviously, if it melts), then it's going to be flammable again. So my educated guess is that while you can't actually light these special alloys on fire, if you were to throw some into an ongoing inferno, it would heat up and then combust. So in an otherwise flammable environment cough hydrogen airship cough, maybe not the greatest idea.
    - TheDudeMan 4y ago
      Bad conclusion. If your airship has become hot enough to burn magnesium alloy, your airship is already dead (as is whatever it landed on).
      - nwiswell 4y ago
        For an airship of the size proposed in that post, I don't think I agree. Presumably there would be some measure of compartmentalization, ventilation, and fire suppression so that even if a portion of the craft was stricken, the entire vessel would not be doomed. But even so, there's going to be a point where there's just too much fuel to keep the fire under control despite best efforts, and the fire-resistant magnesium could certainly contribute to reaching that threshold once you cross a certain temperature. And you cannot simply vent combusting magnesium the way you can vent combusting hydrogen (hypothetically, anyway).
umvi 4y ago
Mainly in elemental form. When properly alloyed its explosive/flammable properties can be mitigated.
83 4y ago
Magnesium parts are already in widespread use. The covers you see on the sides of motorcycle engines/transmissions are often magnesium. In solid form the risk is mitigated because there isn't enough surface area for the reaction with oxygen, it's the powder/shavings that are a concern. You can actually weld magnesium parts without it igniting. Reading up on it a little more - it seems with enough heat solid magnesium can start a self-sustaining burn without oxygen. I wish I could find a laymans explanation of the difference between oxygen fueled magnesium powder fire and self sustaining. Must take an awful lot of heat if a welding arc isn't hot enough to cause this. Edit: Also think of steel wool and how well it burns, but a block of steel not so much.
- forgotusername6 4y ago
  I used to have a flowerpot furnace and cast small objects. I once stumbled upon a car that had been burnt out. The engine block had dripped down the road and I was able to collect some of the melted pieces. It would pop and spit when poked once cast, very different to the aluminium I often used, and I wondered at the time whether it was the magnesium in the block that was doing it.
- BurningFrog 4y ago
  If the magnesium is not reacting with oxygen, it must react with something else to produce more heat than is put in. I discount the possibility of nuclear reactions :)
- lazide 4y ago
  Welding arcs definitely can cause magnesium fires. Generally the shielding gas used to protect from oxidation prevents it, but it's easy to screw up. It's a tricky metal to weld because of it. Generally you also need to preheat it so you don't get cracking, which makes it even more of an issue. There is a passivated oxide layer that forms (similar to aluminum) which generally reduces the risk, but if it's compromised (like from cleaning the weld area)....
- GravitasFailure 4y ago
  Magnesium can't burn without oxygen, but it will happily rip the oxygen out of water and sand, making it exceptionally annoying to put out.
deleted 4y ago
[deleted]
klyrs 4y ago
Old timers recall the infamous case of the NeXT Cube... https://web.archive.org/web/20000817013818/http://simson.net/photos/hacks/cubefire.html https://web.archive.org/web/20000817013818/http://simson.net...
- reaperducer 4y ago
  "This is so NeXT," I told Sally. "Everything works great in the tests, then when you try to make it work for real, in the field, nothing works. They build a computer out of magnesium, and it doesn't even burn!"
- dzuc 4y ago
  https://www.flickr.com/photos/nitroba/albums/72157594435480450 https://www.flickr.com/photos/nitroba/albums/721575944354804...
- umvi 4y ago
  Wow, that story is a great example of "it's better to ask for forgiveness than permission". Just drive to the desert and burn it, don't waste 100 hours trying to get permission from the state of California to burn it.
  - klyrs 4y ago
    Is it though? They got a bunch of assistance from the folks at Lawrence Livermore, and the photographer was happy to not take pictures of fire in direct sun. Asking permission likely got a much better outcome; the author sounded pretty unprepared to ignite the thing without the help he got.
dbcurtis 4y ago
Magnesium metal will burn very violently once it gets going. Among the biggest trouble I got into in high school was when my chem lab partner and I decided it would be entertaining to burn a small piece of magnesium metal. It was rather spectacular, and indeed entertaining. Well worth the Very Stern Lecture. Some aircraft historian will have to fill in the gaps in this story (what aircraft?), but back during the Korean War era, the USAF had a multi-engine piston-driven plane that was either a transport or a cargo aircraft -- not sure which, but the engine blocks were magnesium to save weight. One of the biggest brown-factor events that you could have was an engine fire, because once it got started, your day was going in a bad direction very fast. A friend's dad was pilot-in-command of a plane fresh out of maintenance. An engine caught fire on climb out. He ordered the rest of the crew to hit the silk and he tried to get back to the field. He did, but the landing was not pretty, and he suffered a nasty leg injury. No more combat rating for him, and he finished is USAF career flying transports, and later had a career as a commercial airline pilot. He was luck to survive that engine fire event.
- deleted 4y ago
  [deleted]
londons_explore 4y ago
Oddly, tiny chunks/slivers of magnesium are very flammable, but a big chunk of it is pretty much impossible to set fire to. Source: I was disappointed to buy a few lbs of magnesium to burn on the bonfire, only to find that chucking a lump of it on the bonfire doesn't even burn. Shavings did though.

not-my-account 4y ago

Magnesium reacts with water, so I assume that another metal would be used to make some stable alloy?

deleted 4y ago
[deleted]
s0rce 4y ago
Magnesium is protected by a passive oxide layer and isn't particularly water reactive (unlike sodium and potassium which will react with water more readily). You can toss a chunk of magnesium and water and nothing happens.

v8xi 4y ago

I love ideas around extracting minerals from seawater since there is just so much. e.g. estimated 4.5B tons of uranium in seawater, ~1000x higher than land sources. Pretty much everything is dissolved in there, but the energy requirements are insane

amiga-workbench 4y ago

There used to be a plant near me which did something similar (extract magnesium oxide from seawater), it finally got demolished in 2012 and they're building houses on the land. https://hhtandn.org/venues/287/steetley https://hhtandn.org/venues/287/steetley https://co-curate.ncl.ac.uk/hartlepool-magnesia-works/ https://co-curate.ncl.ac.uk/hartlepool-magnesia-works/

macinjosh 4y ago

Ok, hear me out. If stripping these minerals from the land had a negative impact wouldn’t stripping them from ocean water (which is the medium containing life, unlike ore) may also have negative consequences?? Seems to me like a pretty drastic alteration of ocean water chemistry in the long term. What if animal biology expects the magnesium to be available?

danans 4y ago
That's true if the minerals extracted are consumed completely. Metals however, are often the most recyclable materials we use, because unlike carbon-based materials like plastics, metals often have useful properties in their elemental state, or as alloys that can be melted down and reused without the loss of those properties or of much material. Most aluminum, for example is recycled, because the cost of recycling it is lower than the cost of mining new material.
- throwaway4aday 4y ago
  The concern isn't that we'll completely deplete the ocean, that would be a monumental task. The worry is about what happens at the "mining" sites. Those are going to be in continuous operation for a long time.
  - danans 4y ago
    Assuming that the magnesium is coming from the seawater and not the seabed, would we not expect currents to re-balance the concentration? In fact, we would design the facilities to ensure that it happened.
jillesvangurp 4y ago
Eh no. Oceans are big. Really big. Unbelievably big even. We're talking about filtering tiny fractions of ocean water, and nowhere close to all of it. Literally a drop in the ocean in comparison. So, no. This is not a serious concern.
- 4y ago

ChuckMcM 4y ago

If you are wondering "how" they are doing this, I believe this company is the externalization of this research: https://www.innovationnewsnetwork.com/new-method-extract-magnesium-from-seawater/25685/ https://www.innovationnewsnetwork.com/new-method-extract-mag... (Kind of hard to pin down exactly since they don't say a lot about how they are doing it, but a quick check suggests this is the only "new" thing in extracting magnesium recently and Magrathea is a young company[1]) [1] https://www.crunchbase.com/organization/magrathea-metals https://www.crunchbase.com/organization/magrathea-metals

whatshisface 4y ago
Externalization? Do you mean commercialization?
- ChuckMcM 4y ago
  Effectively yes. I tend to think of research to product in two phases, phase one is "externalization" which involves taking something done in the lab and reproducing it in a scalable process, step two is "commercialization" which is to capture market share. I use two phases because each phase captures very different risk profiles relative to the technology.
avernon 4y ago
They mention that they are doing electrochemistry. A huge portion of historical magnesium production is from electrolysis, including the only operating plant in the US. Past methods have used lime to precipitate magnesium (Dow) or evaporation ponds to concentrate it (the current Utah plant). Probably the new thing they are doing is using something like Chlor-Alkali to make base that precipitates the magnesium instead of using lime. Then the electrolysis of molten magnesium salts would be similar to products of today. There is some chance they have improvements in these areas, but there are really only so many options. The job descriptions they've posted support this hypothesis. Recently most magnesium comes from China. They mine ore, throw it in a coal-fired furnace along with some reducing agents, then collect pure magnesium vapor. This process is more labor and energy intensive, but has significantly less CAPEX. Works for China. Chlor-alkali is more expensive than lime and the back-end electrolysis is more expensive than thermal reduction. So I'd be skeptical they are going to lower costs without some kind of CAPEX reducing magic for molten salt electrolysis.

speed_spread 4y ago

Of similar interest, magnesium production from accumulated mine tailings : https://alliancemagnesium.com/en/products/primary-magnesium/ https://alliancemagnesium.com/en/products/primary-magnesium/

thepangolino 4y ago
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stevespang 4y ago

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UberFly 4y ago

That website is really lacking any worthwhile details. Are they just fishing for venture capital at this point?

EarlKing 4y ago
Well, you must understand that they only just awoke from a few million years of sleep to discover their entire cleaning staff is dead. Who's going to pick up the bodies? That's what nobody seems to have an answer to...

gdsdfe 4y ago

it looks like somebody's school homework

philipkglass 4y ago

There are two major ways of producing magnesium [1]: 1) Electrolytic production from anhydrous magnesium chloride, similar to the electrolytic production of aluminum. 2) The Pidgeon process, which currently dominates Chinese (and world) magnesium production. It distills magnesium vapor under vacuum from a heated mixture of ferrosilicon and magnesium-calcium oxide (calcined dolomite). The Pidgeon process has a high global warming potential because of the coal used to produce the ferrosilicon input and to heat the retorts. The electrolytic process has a lower global warming potential, especially if using low-carbon electricity, but historically sulfur hexafluoride has been used as a protective cover gas for the metal during electrolytic production. This gas has a staggering global warming potential 23,900 times that of CO2 [2] so incidental leakage of even small quantities can have a high climate impact. The "without mining" part is not novel. Dow Chemical produced electrolytic magnesium from seawater without mining at Freeport, Texas from 1941-1998, until lower cost foreign magnesium made it uneconomical: https://www.chemicalonline.com/doc/dow-to-exit-magnesium-business-0001 https://www.chemicalonline.com/doc/dow-to-exit-magnesium-bus... Reading the company's rather sparse public info, it looks like this is a revival of the same basic kind of process as Dow used. But since it's focused on certifying a low GWP for its magnesium, the company will not use sulfur hexafluoride. ("We’re piloting a new generation of electrolytic production technology that is inherently carbon neutral, removing the need for coal and carbon-intense reagents like FeSi and SF6.") They don't say it directly but they also must be using clean electricity for the electrolysis, otherwise the metal would still be fairly CO2-intensive. Unfortunately, the latest news item from their news page is about a threat to their business: "State of Utah denies US Magnesium’s request to extend canals into the Great Salt Lake threatening shutdown of the only American magnesium producer" https://sltrib.pressreader.com/article/6830844853434424 https://sltrib.pressreader.com/article/6830844853434424 [1] https://ro.uow.edu.au/cgi/viewcontent.cgi?article=2295&context=engpapers https://ro.uow.edu.au/cgi/viewcontent.cgi?article=2295&conte... [2] https://en.wikipedia.org/wiki/Sulfur_hexafluoride#Greenhouse_gas https://en.wikipedia.org/wiki/Sulfur_hexafluoride#Greenhouse...

jacquesm 4y ago

If you're wondering about where the name Magrathea comes from: https://hitchhikers.fandom.com/wiki/Magrathea https://hitchhikers.fandom.com/wiki/Magrathea

dunham 4y ago
I knew it was from the book, but I'd forgotten exactly what Magrathea was, so I started reading the article. Halfway through I got a kernel panic (macos 12.6.2 / intel).
- jacquesm 4y ago
  Probably just some old cyber defense systems taking the occasional potshot to relieve the monotony ;)
  - mrlonglong 4y ago
    Marvin most likely

ummonk 4y ago

It's not "impossible" to decarbonize the production of aluminum without driving up cost, as the page claims. Once green electricity and hydrogen is cheaper than CO2-emitting energy, this will be possible and even profitable.

tekno45 4y ago
Isn't new renewable power cheaper than new C02 power?
- garettmd 4y ago
  From what I understand, it is cheaper. However, that's just with new power. Most of the power available now is from existing installations, making existing fossil fuel power cheaper than any new installations.
- marcusverus 4y ago
  I've yet to hear about renewables that put out consistent power cheaper than gas. You'll see the occasional article about new solar that's claimed to be cheaper than gas, but they never have sufficient storage to actually stand on their own two feet. The last one that was posted here on HN was claimed to be cheaper than gas, but it only had enough storage to output 1/2 of its daytime production overnight. In other words, it was cheaper than gas... as long as you've got redundant gas plants to provide power overnight. Always read the fine print when folks are pitching "cheap renewables".
- Taniwha 4y ago
  The Hall–Héroult process (electrolysis of alumina to make aluminium) uses a sacrificial carbon anode - every 2 atoms of Al you produce results in 3 CO2 molecules - so for every kg of Al you make ~2.4 kg of CO2
hannob 4y ago
The problem with decarbonizing is not being solved with green electricity and hydrogen. The (direct) emissions come from the carbon anodes that are consumed in the process. They are usually made from petroleum coke, aka they're fossil fuels. Alternatives are being developed, but have a somewhat troubled history. Alcoa announced in the early 2000s that they are only months away from deploying inert anode technology. They're still not there (though still working on it in a project called elysis).

geuis 4y ago

This entire website and company reads like a penny pink sheets stock scam. "Magrathea sells metal using multi-year supply agreements in countries with enforceable contract law. Supply agreements allow our partners to build in magnesium with confidence. We prevent price instability from Chinese trade manipulation so the innovative products of our partners can succeed in the market." There's absolutely no information on the site detailing their tech. Just a lot of buzzwords. Under the News section, it's the typical list headline articles cherry picked to make the company sound better.

EarlKing 4y ago
"Greetings to you. This is a recorded announcement as I am afraid we are all out at the moment. The commercial council of Magrathea thanks you for your esteemed visit but regrets that the entire planet is temporairly closed for business. If you would like to leave your name and the address of a planet where you can be contacted kindly speak when you hear the tone... *BEEEEEEEP*."
marcosdumay 4y ago
Somehow we should expect them to be able to purify magnesium from brine, and yet not be on the market selling lithium. That's extremely odd. Edit: Turns out that no, it's simpler to separate magnesium and calcium than lithium, even those existing in much smaller amounts. Those metals form many solid ionic compounds, with anions that would keep sodium and lithium soluble.
- runnerup 4y ago
  The majority of the magnesium used for WW2 explosives was produced from brine near Freeport, TX. (I think? need to double-check this) Edit: During WW2 additional production facilities around the USA were brought online. Before and after WW2, except for a moment during the Korean War, Dow's facility in Freeport, TX was the only producer of magnesium in the USA. It peaked in capacity in the 1970's. There were several other endeavors by other companies to produce magnesium over time with different technologies. Most magnesium production in the USA has been eliminated for economic reasons.
4y ago

sbierwagen 4y ago

Brine mining isn't new, of course. Table salt is the canonical example of a metal compound extracted by evaporating brine, but there's a dozen other elements that are harvested at scale for profit from various brines: https://en.wikipedia.org/wiki/Brine_mining https://en.wikipedia.org/wiki/Brine_mining including Magnesium https://en.wikipedia.org/wiki/Brine_mining#Magnesium_and_magnesium_compounds https://en.wikipedia.org/wiki/Brine_mining#Magnesium_and_mag... If you're in the bay area, you've seen a brine mine dozens of times: https://en.wikipedia.org/wiki/San_Francisco_Bay_Salt_Ponds https://en.wikipedia.org/wiki/San_Francisco_Bay_Salt_Ponds

culi 4y ago
I've wondered about these salt evaporation ponds a lot. It's the traditional way sea salt has been harvested in Japan from the sea and also in the mountains of the Andes from mountain deposits of salt water. And it is still harvested industrially like that on some islands. The thing I'm really curious about is this is happening on a large enough scale does it begin to affect the amount of precipitation that can occur? I'm wondering if it can be utilized to increase rainfall during times of drought Maybe even long canals to transport the ocean water far inland in very shallow streams that are meant to be evaporated by the sun over time. This uses almost no energy on our part, produces salt, and might possibly help increase rainfall?
- AndrewDucker 4y ago
  Remembering that water flows downhill, and places a long way inland are likely to be significantly higher than sea level, I'm not sure how feasible digging long canals many miles inland will be. Particularly if they will then fill up with salt.
- temporary22 4y ago
  Salt kills most plants. Bringing it inland would basically stop agriculture for hundreds of meters surrounding the canal. If it goes into the aquifer it's even worse. Also, inland is usually higher than sea level (where it's lower you get lakes / ponds / swamps, unless it's actively managed), so you would be creating ditches a hundred meters deep if not more. I'm also not sure that local water would increase rainfall, any amount of wind would sweep moisture off immediately. The most it can do is to increase the humidity of the surrounding area when windless.

ctoth 4y ago

I checked Linkedin and couldn't find a Slartibartfast, are we sure this company is legit?

pstuart 4y ago

If this is mining brine, then it would be a perfect pairing with a desalinization plant.