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Metal Without Mining

magratheametals.com

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Re: Metal Without Mining

#71

Post by yellowapple »

throwaway4aday wrote: post #39
yellowapple wrote: post #25

Earlier quoted context omitted.

My idea is to combine this with desalination. California could permanently end its droughts and become a major magnesium supplier in one swell foop.

You'd also need to think up good uses for the sodium chloride or dump it somewhere. The sulfate, potassium and calcium would probably be useful if they could be easily separated but the sodium and chloride ions are by far the majority and are not going to be profitable in comparison to the current operations we use to obtain them.

> You'd also need to think up good uses for the sodium chloride or dump it somewhere.

Okay, so California ends its drought permanently and becomes a major supplier of magnesium and table salt.

Slightly-less-facetiously: sodium chloride has all sorts of industrial uses (on top of its culinary uses). The good uses are, in other words, already thought up in droves.

Further, most salt production already entails taking seawater and pulling out the water. Ain't too much of a stretch to, you know, actually keep the water instead of letting it evaporate into the atmosphere.

Re: Metal Without Mining

#72

Post by [deleted] »

justinator wrote: post #61
jillesvangurp wrote: post #15

Earlier quoted context omitted.

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.

Every time there's a natural resource humans want to exploit, this is almost always been an argument, and it's almost always been wrong. "look how many fishes are in the river! You can walk across the river by standing on the fishes!" "Look how trees are in this forest! You can't see the end!" Not to get all Derrick Jensen on this, but a red flag has been raised in my mind, as has my left eyebrow.

[deleted]

Re: Metal Without Mining

#73

Post by danans »

throwaway4aday wrote: post #20
danans wrote: post #14

Earlier quoted context omitted.

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…

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.

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.

Re: Metal Without Mining

#74

Post by umvi »

klyrs wrote: post #19
proee wrote: post #2

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

Old timers recall the infamous case of the NeXT Cube... https://web.archive.org/web/20000817013818/http://simson.net...

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.

Re: Metal Without Mining

#75

Post by klyrs »

umvi wrote: post #74
klyrs wrote: post #19

Earlier quoted context omitted.

Old timers recall the infamous case of the NeXT Cube... https://web.archive.org/web/20000817013818/http://simson.net...

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.

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.

Re: Metal Without Mining

#77

Post by avernon »

ChuckMcM wrote: post #65
avernon wrote: post #33

Earlier quoted context omitted.

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…

Not to be too snarky here, did you read the link to the research? It too uses electro-chemistry with the defining feature: "This new process produces pure magnesium hydroxide, allowing researchers to skip energy-intensive and expensive purification steps." My reasoning was to note that the Magrathea collateral is pushing "low energy" to make the connection. I am NOT saying I KNOW that this how they are doing it. It i…

Yes, I read the underlying paper a while back. It only looks at the very first step of a Dow-like process, before any electrochemistry happens. Instead of dumping hydroxide in a tank, they expose it to hydroxide in a serpentine flow path. When I was reading into this before calcium didn't seem to be too big of a problem for the Dow process because the calcium compounds are more soluble than magnesium hydroxide. They were actually adding more calcium with the lime. So their comparison may be to a different method than the Dow Process. It didn't seem particularly useful.

Then you neutralize the magnesium hydroxide with hydrochloric acid to make Magnesium chloride and do molten salt electrolysis on it to make pure magnesium and chlorine.

Re: Metal Without Mining

#78

Post by TheDudeMan »

nwiswell wrote: post #30
omnicognate wrote: post #7

Earlier quoted context omitted.

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?

> 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 form…

Bad conclusion. If your airship has become hot enough to burn magnesium alloy, your airship is already dead (as is whatever it landed on).

Re: Metal Without Mining

#79

Post by nwiswell »

TheDudeMan wrote: post #78
nwiswell wrote: post #30

Earlier quoted context omitted.

> 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 form…

Bad conclusion. If your airship has become hot enough to burn magnesium alloy, your airship is already dead (as is whatever it landed on).

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).

Re: Metal Without Mining

#80

Post by mrlonglong »

jacquesm wrote: post #52
dunham wrote: post #45

Earlier quoted context omitted.

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).

Probably just some old cyber defense systems taking the occasional potshot to relieve the monotony ;)

Marvin most likely
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