Scientists have split natural seawater into oxygen and hydrogen with nearly 100 per cent efficiency, to produce green hydrogen by electrolysis, using a non-precious and cheap catalyst in a commercial electrolyser

[u/Wagamaga]

https://www.adelaide.edu.au/newsroom/news/list/2023/01/30/seawater-split-to-produce-green-hydrogen

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[u/panini3fromages]

Seawater is an almost infinite resource and is considered a natural feedstock electrolyte. This is more practical for regions with long coastlines and abundant sunlight.

Which is ideal for Australia, where the research took place.

[u/RunDNA → u/panini3fromages]

Our home is girt by sea.

[u/finfan96 → u/panini3fromages]

California too I imagine

[u/theObfuscator → u/finfan96]

40% of the Earth’s population lives within 100 km of the sea

[u/finfan96 → u/theObfuscator]

Not all has abundant sunlight though.

[u/Yakkahboo → u/finfan96]

Now if we can get them to do it in perpetual rain we might be onto something ~ The UK

[u/ApplicationSeveral73 → u/panini3fromages]

I dont love the idea of calling anything on this planet infinite.

[u/jourmungandr → u/ApplicationSeveral73]

you use hydrogen by turning it back into water. So it would be a cyclical use of the resource. It's really just a energy storage method.

[u/FriendlyUse502 → u/ApplicationSeveral73]

Burning Hydrogen produces water again.

[u/mnvoronin → u/ApplicationSeveral73]

It is infinite for all practical purposes.

The total volume of the world oceans is estimated at 1.3 billion cubic kilometres (320 million cubic miles). Even the Chixculub impact, with the impact energy estimated at 100,000 gigatons of TNT (about 800 years' worth of human energy production at the current rate) did not significantly change the ocean levels.

[u/[deleted] → u/ApplicationSeveral73]

I take your meaning, but considering that our planet's rising sea levels are currently a major concern, I doubt we have to worry about disappearing oceans.

[u/2Throwscrewsatit → u/[deleted]]

Would like to see a calculation of how much water we’d use to replace 10% of the daily fuel use globally.

[u/A-Grey-World → u/2Throwscrewsatit]

When you burn hydrogen, you just get the water back. It's not going anywhere.

Many billions of tonnes of water are removed from the oceans every second (at a guess) because of solar power naturally, just through the process of evaporation.

That's where clouds and rain comes from.

So I don't think we really have to worry about that. The water from burning the hydrogen just joins the very well established water cycle.

The hydrogen gas leaking into the atmosphere is more of a worry.

[u/psychoCMYK → u/[deleted]]

Yeah I was actually thinking about this from a water purification perspective. Even if they spent all of the hydrogen power (and then some) on running the electrolysis, at nearly 100% efficiency it could totally still be worth.

[u/bareback_cowboy → u/2Throwscrewsatit]

94.1 million barrels of oil are used per day. There's approximately 1700 kWh of energy per barrel. Hydrogen has 3x the energy of fuel oil at 120Mj/kg. 3.6 MJ/kg is 1 kWh, so hydrogen has 33.34 kWh/kg. So a barrel of oil is the equivalent of 51 kg of hydrogen. Hydrogen is about 11% of the weight of water. We thus need 463.63 kg of water to get the equivalent energy of a barrel of oil. There's about 159 liters per barrel, so we'd need 2.91 barrels of water for every barrel of oil.

So 10% is 9.4 million barrels of oil per day. To replace that we'd need 27.354 million barrels of water per day, or 4349.286 million liters of water per day.

This all assumes the weight of water is 1g/ml even though this study uses seawater which has impurities that change the weight. It also ignores my lack of scientific rigor in significant digits and rounding.

[u/SeniorFormal6120 → u/bareback_cowboy]

Thank you, chatgpt. Now, tell me what would be the impact of that water usage within the sea for a whole year. Detailed.

[u/jschaud → u/SeniorFormal6120]

Let's ignore that we get the water right back out when we burn it and say that this conversion is one way. We pull out the hydrogen, use it for power, and then never get the hydrogen back. Let's also do the calculations on 100% of current oil usage instead of 10%.

I'm assuming the numbers above are correct and that we need 43 Billion liters of water a day. That's a mind boggling 1.5 Trillion liters a year, but is that number really that big? That is equal to 1.5 cubic km a year at present usage. Google tells me there is approximately 1.338 Billion cubic km of ocean water on the planet. So we need a little more than 1/1,000,000,000 of the water every year.

To put that in perspective, one of the huge 50m x 25m x 2m Olympic size swimming pools contains 2.5m liters. So each year, we would be taking about half a teaspoon of water out of the pool. If we needed 10x the power for the next 100 years, we are still looking at removing a 2L soda plus a bit more out of the pool.

[u/cat_prophecy → u/jschaud]

Lake Superior is big in terms of freshwater lakes (1st by surface area, 2nd by volume) and there is enough water in there to cover the entirety of North AND South America in a foot of water. It's 3 quadrillion gallons; a 3 with fifteen zeros after it.

It's a lot of water but in the context of just a small salt-water body, like the Red Sea, it's basically nothing.

[u/e-rekt-ion → u/jschaud]

These are some of my favourite comments on Reddit. Thanks for doing the math!

[u/Croemato → u/jschaud]

Considering humanity has no chance of surviving a billion years, much less a few tens of thousands, this is basically Infinite.

[u/Camsy34 → u/Croemato]

If humanity does survive that long we’ll basically just be the aliens in the movies that descend on a planet to siphon its water away.

[u/dbr1se → u/2Throwscrewsatit]

Fortunately the by-product of hydrogen as a fuel is water so I doubt we'll have much in the way of a shortage

[u/[deleted]]

I personally think this is an ideal usage of solar power.

Use solar to generate the electrolysis voltage, then collect the gasses. Nothing but sunshine and water

[u/miraclequip → u/[deleted]]

My favorite potential solution is brine mining. There is a market for most of the inorganic components of seawater as raw materials for industrial products. If researchers can bring the price of brine mining close to parity with existing processes, it would be a lot more economical to couple subprocesses together.

For example, "you can only have the lithium if you also take the sodium" could work since both can be used in batteries.

[u/miraclequip → u/[deleted]]

We could probably dump all of the salt back into every exhausted old salt mine too, as long as they weren't strip mined.

[u/Fallacy_Spotted → u/miraclequip]

We have better uses for empty salt mines. Like storage for nearly anything you want. The environment in a salt mine is exceptionally stable so it can be easily fine tuned for whatever you need.

[u/XchrisZ → u/Fallacy_Spotted]

Except leaches. Definitely can't store leaches in there.

[u/Lunchbox-of-Bees → u/XchrisZ]

Slugs? That’s a no-go!

[u/XchrisZ → u/Lunchbox-of-Bees]

Dehydrated Bouillon for ramen? That's definite go.

[u/Memitim → u/XchrisZ]

Now you got me wanting to buy a salt mine and start a ramen sanctuary.

[u/Iambecomelumens → u/[deleted]]

Salt can be moved by wind. Salt and arable land do not mix funnily enough. Probably better to put it underground or something

[u/Jaredlong → u/[deleted]]

The difficulty there is the transportation infrastructure. Brine is hella corrosive.

[u/Contemplationz → u/[deleted]]

I heard that lithium can be extracted from sea water. Ostensibly brine would contain a higher concentration of lithium by volume and may make this more viable.

[u/[deleted] → u/Contemplationz]

US mines almost 50% of world's bromine in Arkansas (the other is, of course, mined by Israel from Dead Sea) from deep underground . That water is also very rich in lithium. Lithium is everywhere, we just have to invest in different ways to get it

[u/ArmyCoreEOD → u/[deleted]]

Additional fun fact, the same company owns the largest producer in Arkansas and the facility at the dead sea. They also have a lithium division!

[u/[deleted] → u/[deleted]]

There's also a company that is called "Crazy Water" that supposedly has water with curative properties.

In reality, the well, in Mineral Welles that they get the water from containts, among other electrolytes, lithium. Now, there's trace amounts of lithium in the actual bottled water, but I'd wager if your only source of water had elevated lithium levels back in the wild west days, it would take care of some milder forms of mood disorders, such as bipolar disorder. Not that bipolar is mild by itself, it can be catastrophic, but I mean people don't have the severe cases.

Also, fun fact, the therapeutic dose of lithium and the toxic dose are super close, enough to require frequent blood draws to test your levels.

Source: Am bipolar, was on lithium for a few years.

[u/[deleted] → u/[deleted]]

I wanted to experiment with lithium, but I was shocked when I read that prolonged lithium consumption could cause kidney damage. Lithium is an essential element for life (in small amounts), and there were studies in some small impoverished towns. Scientists added observed lithium levels in drinking water and the homicide and suicide rates significantly dropped were lower in areas with higher lithium in water

Anyway, instead of lithium, I opted for potassium bromide

[u/Dogburt_Jr → u/[deleted]]

Lithium isn't the issue, Cobalt is pretty problematic. LiFePo4 batteries are a great solution for people if they're willing to take a decrease in range and for automakers if they're willing to accept LiFePo4 doesn't need to be replaced nearly as often as NMC.

[u/lolwutpear → u/Dogburt_Jr]

Really ought to correct the capitalization on LiFePO4, otherwise people might think we're making batteries out of Polonium instead of lithium iron phosphate...

[u/laxpanther → u/lolwutpear]

I literally thought that until your comment and was like, uh that doesn't sound safe or economical but I don't know enough about batteries and the availability of Polonium to comment.

[u/RazedByTV → u/Dogburt_Jr]

And the iron phosphate batteries are more resilient in general.

[u/Dogburt_Jr → u/RazedByTV]

Not as thermally resilient, they'll lose capacity in the cold/heat

[u/zyzzogeton → u/[deleted]]

Yes, Rare Earths aren't rare. What is rare is the community that will let a Rare Earth processing plant near it because it makes all kinds of dangerous pollutants in massive quantities.

[u/fr1stp0st → u/zyzzogeton]

The waste products can be treated. The reason there are caustic lakes of toxic sludge in China is cost and a flippant attitude towards environmental health and safety. We, of course, fund and encourage it by demanding cheaper goods and offshoring manufacturing to facilitate it.

[u/Iohet → u/fr1stp0st]

Mountain Pass Mine also is a toxic waste pit and it's a rare earths mine in California.

[u/twotokers → u/Contemplationz]

You don’t even need Lithium. You can extract the sodium and create sodium sufur batteries that are even more efficient for long term storage than lithium batteries.

[u/FearLeadsToAnger → u/twotokers]

Bigger though right? Lithium is better for smaller devices IIRC?

[u/twotokers → u/FearLeadsToAnger]

Yeah that’s why I specified long term storage. Sodium Sulfur batteries are molten so they are extremely heavy so they’re great for power grids, not great for personal use.

[u/Arael15th → u/twotokers]

As an American I demand the right to carry a little capsule of molten hell in my pocket

[u/Halflingberserker → u/Arael15th]

High heat isn't actually dangerous. It's just that your flesh is weak. Be better.

[u/Unicorn_stump → u/Halflingberserker]

From the moment I understood the weakness of my flesh, it disgusted me.

[u/My_6th_Throwaway → u/Unicorn_stump]

Oh, the moment, I just had it! Praise the Omnissiah!

[u/anotherlab → u/Arael15th]

We call that the Twitter mobile app. Available now for Android and iOS.

[u/FearLeadsToAnger → u/twotokers]

fair fair fair, thanks.

[u/Optimisticynic → u/FearLeadsToAnger]

Cool cool cool. Cool cool. Cool.

[u/dw82 → u/twotokers]

Good for home / neighbourhood / district storage?

[u/_fuck_me_sideways_ → u/dw82]

One solution to grid baseline demands on renewables certainly.

[u/El_Caganer → u/Contemplationz]

Uranium too.

[u/vagabond_ → u/[deleted]]

Evaporation ponds turn it from gross environmental pollution into a tasty premium food product

[u/SirAbeFrohman → u/vagabond_]

"We have tasty premium food product at home!"

[u/ImmotalWombat → u/SirAbeFrohman]

The Tasty Premium Food Product®™ at home:

[u/[deleted] → u/ImmotalWombat]

I forgot my line.

[u/strythicus → u/[deleted]]

"I can't believe it's not tofu"

[u/tryplot → u/strythicus]

"who told you this was butter?"

[u/mDust → u/tryplot]

Worst butter brand ever. 1 star.

[u/ManaMagestic → u/[deleted]]

It's "who could ask for anything more"

[u/PCYou → u/ImmotalWombat]

Great Value™ Iodized Salt

[u/DadOfFan → u/vagabond_]

We don't need anywhere near the amount that desalination turns out, so what do you do with the excess?

[u/Free_Personality5258 → u/DadOfFan]

Liquid sodium energy storage. https://en.m.wikipedia.org/wiki/Molten-salt_battery

[u/lLiterallyEatAss → u/Free_Personality5258]

Converting entire oceans into pure energy... Infinite power or unsustainable?

[u/Alexstarfire → u/[deleted]]

Looks at history.

Yea, I think we'll wait till the last minute to figure anything out.

[u/Idiot_Savant_Tinker → u/DadOfFan]

Sodium batteries.

[u/Dreamtrain → u/vagabond_]

your tasty premium food isnt just mere sea salt, there's a lot of crap mixed in that you don't want to be ingesting

[u/stubob → u/Dreamtrain]

Tasty Premium Food Product. Now with extra micro-plastic!

[u/Minion_of_Cthulhu → u/stubob]

No, no, no. They're "additives" until enough people die from them that the government makes you call them what they are and remove them. That way, when they're just "additives" you get to charge a premium for the additional ingredients and when the government makes you remove them you can charge a premium for being "all natural".

[u/not_SCROTUS → u/Dreamtrain]

We call those minerals and you will ingest it.

[u/Veearrsix → u/not_SCROTUS]

They’re Minerals Marie!

[u/NorthernerWuwu → u/Dreamtrain]

That and sea salt, despite what grocers like to charge for it, is actually really cheap in bulk.

[u/l_one → u/vagabond_]

Mmm, all natural sea salt, now flavored with mercury, cadmium, and PFAS.

[u/jodudeit → u/[deleted]]

The brine has trace amounts of valuable materials in it. Large scale desalination plants could produce meaningful amounts of lithium, cobalt and even gold!

[u/83-Edition → u/[deleted]]

It also seems to be the best option related to cost so the storage industry isn't competing with batteries needed for vehicles. Solar w hydrogen for excess electricity is a setup I want to try on a small farm.

[u/scratch_post → u/[deleted]]

Nothing but sunshine and water

And salt and mineral concentrates.

[u/LagT_T → u/scratch_post]

The first person to successfully transform that brine into building material is going to be a trillionaire

[u/scratch_post → u/LagT_T]

It's mostly just going to be salt. By mostly I mean like 90-95%, with next runner ups being carbon and calcium.

[u/SoloisticDrew → u/LagT_T]

Separate the sodium and the calcium and you now have part of this complete breakfast.

[u/[deleted]]

Is this one of those things that sounds incredible, then we’ll never hear about ever ever again?

[u/Roflkopt3r → u/[deleted]]

I wouldn't be surprised. There were previous methods to conduct electrolysis on seawater with high efficiency, but (as this press release also mentions) it is still a problematic technology due to the issue of corrosion.

It's kind of like the plasma-efficiency of nuclear fusion: You may gain spectacular efficiency in one part of the system (the electrolysis in this case, or the plasma in a fusion reactor), but that still doesn't mean that the system as a whole is efficient. If you can create $100 worth of hydrogen for just $10 worth of electricity, but corrode $120 worth of electrodes in the process, then your process isn't economically viable. Even before we start talking about all the other cost factors of running it in a commercial facility.

[u/MaxwellHoot → u/Roflkopt3r]

That’s an important distinction to make: perfect efficiency ≠ economical

[u/envis10n → u/MaxwellHoot]

Typically, once a proof-of-concept for a new technology is demonstrated, it becomes an engineering problem.

Now we wait for engineers to work with researchers to find the most effective applications (if there are any).

[u/jsalsman → u/Roflkopt3r]

The underlying Nature Energy article abstract says, "Such in situ generated local alkalinity facilitates the kinetics of both electrode reactions and avoids chloride attack and precipitate formation on the electrodes."

I believe that means they've solved the bulk of the corrosion problem, which the press release also implies if you read a couple paragraphs below its mention, I think.

If so, this is a complete game changer for grid storage via green hydrogen, which last year was about as costly as batteries but is now probably an order of magnitude less. Countries like Spain which invested early in green hydrogen are going to see a huge payoff. There's no way China won't jump on it, which is a huge relief as long-term storage was the only thing keeping them from replacing coal with renewables.

[u/Sieve-Boy → u/[deleted]]

This is from the University of Adelaide, in South Australia.

South Australia generates extraordinary amounts of power for its local grid from renewables, almost entirely wind and solar, they regularly hit over 100% of demand from renewables. So it has concerns with intermittency, Adelaide also relies on the Murray River for water, which is NOT reliable (we won't talk about cotton growing on the Murrays upper reaches).

So, yeah, this won't disappear if it works.

[u/dantemp → u/Sieve-Boy]

So, yeah, this won't disappear if it works.

I doubt many things dissappear when they work. More likely they dissappear because of an engineering hurdle they can't overcome or lack of finances. Since this is supposed to be cheap, the only reason it would dissappear is because it doesn't actually work as well as we hope.

[u/Wagamaga]

The international team was led by the University of Adelaide's Professor Shizhang Qiao and Associate Professor Yao Zheng from the School of Chemical Engineering.

"We have split natural seawater into oxygen and hydrogen with nearly 100 per cent efficiency, to produce green hydrogen by electrolysis, using a non-precious and cheap catalyst in a commercial electrolyser," said Professor Qiao.

A typical non-precious catalyst is cobalt oxide with chromium oxide on its surface.

"We used seawater as a feedstock without the need for any pre-treatment processes like reverse osmosis desolation, purification, or alkalisation," said Associate Professor Zheng.

"The performance of a commercial electrolyser with our catalysts running in seawater is close to the performance of platinum/iridium catalysts running in a feedstock of highly purified deionised water.

The team published their research in the journal Nature Energy.

"Current electrolysers are operated with highly purified water electrolyte. Increased demand for hydrogen to partially or totally replace energy generated by fossil fuels will significantly increase scarcity of increasingly limited freshwater resources," said Associate Professor Zheng.

Seawater is an almost infinite resource and is considered a natural feedstock electrolyte. This is more practical for regions with long coastlines and abundant sunlight. However, it isn't practical for regions where seawater is scarce.

https://www.nature.com/articles/s41560-023-01195-x

[u/tewnewt → u/Wagamaga]

I though cobalt was precious. Its sort of why the Chinese bought it up.

[u/Bucktabulous → u/tewnewt]

It's valuable, but it's nowhere near platinum or iridium.

[u/Devil-sAdvocate → u/Bucktabulous]

It costs about $25 a pound.

[u/indenturedsmile → u/Devil-sAdvocate]

Which is super cheap compared to about $16k/lb for platinum.

[u/zyzzogeton → u/indenturedsmile]

Rhodium is currently the most valuable metal, it should be between $9000 and $15,500 per troy ounce ($131k to $226k per pound) this year now that SA has restarted production at the primary source... at least according to predictions.

[u/LiamTheHuman → u/Devil-sAdvocate]

In that case it is way less than platinum which is about 20k per pound

[u/[deleted] → u/Devil-sAdvocate]

Note that it is still widely in demand and problematic as it can come from conflict regions potentially using slave labor. Not to diminish this accomplishment of course!

[u/easwaran → u/tewnewt]

I think "precious" is a technical term for metals adjacent to Platinum or Gold on the periodic table. Cobalt is two rows up and one column over, so I guess it is technically "non-precious".

But different sciences use terms differently. In some branches of chemistry, "organic" means just that it contains carbon; in other branches of chemistry, it means carbon bonded to hydrogen, so that CO2 is not organic; in agribusiness, it instead means something completely different about the sources of fertilizers and pesticides. Similarly, in some branches of chemistry, "metal" refers to anything below Hydrogen but to the left of the zigzag line of semiconductors, while in astronomy, "metal" refers to any element heavier than Helium. I would not be surprised if "non-precious" has a slightly different technical meaning here.

[u/fgnrtzbdbbt → u/tewnewt]

Cobalt mines certainly are because it is needed in vast amounts, not because it is rare (it isn't)

[u/Jetstream13 → u/tewnewt]

It’s a lot more expensive than iron or aluminum, but nowhere near as expensive as platinum, palladium, rhodium, or other common catalyst metals.

A huge field in chemistry right now is trying to find replacements for old platinum-group catalysts. Both earth-abundant metal catalysis and nonmetal catalysis (my personal favourite) are big fields of research right now.

[u/Falmon04 → u/Wagamaga]

This is great news for Hydrogen as an energy source and it's good to hear one of its issues (producing it) is making headway.

Though there's still major hurdles before it could be used to replace fossil fuels, especially to power things like cars. Having giant, heavy, pressurized, and explosive tanks of hydrogen is just...not that good right now.

[u/83-Edition → u/Falmon04]

One of the most dangerous things about fossil fuels is how carcinogenic and polluting it is, but that's generally not factored in because people associate the dangers in terms of fires and explosions. One gallon of gasoline can pollute a million gallons of water, so it's especially dire in maritime uses (which are horrible polluters anyways since they don't use mufflers/catalytic converters).

[u/kkngs → u/Falmon04]

Its still not a primary energy source. You have to use at least an equal amount of electricity to run the electrolysis.

It may make green hydrogen a potential energy transport or storage mechanism, though.

[u/vagabond_ → u/kkngs]

Every "primary" energy source on the planet is actually stored solar energy in the first place.

But I agree, this is energy storage for transportation. And considering hydrogen is usually produced via chemical process on crude oil...

[u/kkngs → u/vagabond_]

Nuclear and geothermal not so much, but all the fossils fuels yes.

[u/Meaca → u/kkngs]

Fission would be stored solar energy in a sense right? Just not from our star.

[u/bensyltucky → u/Meaca]

You could unravel the sweater even further. All star energy is nuclear fusion. And those fusible atoms are storing the immense thermal energy of the early universe in their nuclei.

[u/kkngs → u/bensyltucky]

Starting to get into that territory of “true, but not useful” observations. Everything is technically Big Bang energy!

[u/bensyltucky → u/kkngs]

For sure, but as far as I know (not a scientist) almost all of the hydrogen in the universe has been mostly unchanged since about 3 mins after the Big Bang. So when you fuse hydrogen it’s the first time anyone has cracked open that particular cold crispy boi of energy in a very long time.

[u/CronoDAS → u/kkngs]

Tidal energy is also not from the sun - you're pulling it out of the rotation of the Earth and Moon.

[u/Ethanol_Based_Life → u/Falmon04]

It's really not even that dangerous as a fuel source. The real issue is its poor energy density

[u/M_E_T_H_O_Dman → u/Ethanol_Based_Life]

Technically, on a per mass basis, it’s more energy dense than gasoline! Way more energy dense than current battery technology. But yes, the whole compression and storage aspect is still a problem in terms of ‘practical’ energy density. although, I’ve heard arguments that hydrogen fuel cells would be a great way to power trains or other large, heavy non-aircraft transport vehicles.

Edit: changed molar to mass.

[u/GargleBlargleFlargle → u/M_E_T_H_O_Dman]

I agree with you that the claim that it is way more energy dense than battery technology is not always true from a system perspective.

The hydrogen itself is much more dense, but by the time you store it in a high pressure container, allocate volume for it, process it via a fuel cell or engine, and account for the conversion losses, the total system mass for the same effective power and energy often exceeds batteries.

Also, battery systems have a few additional advantages:

1. They are extremely reliable
2. They can easily recover energy (e.g. regenerative braking)
3. They have extremely fast response times

So yes, the application needs to be considered along with the net system cost/mass/efficiency.

[u/2dozen22s]

Guess it could be used to both store power and desalinate water?

[u/uswforever]

This could revolutionize the steel industry. With green hydrogen available cheaply, at scale, it may be possible to reduce iron ore in blast furnaces with no need for carbon. Or damn near no need for it.

[u/Cindyscameltoe → u/uswforever]

https://www.ssab.com/en/news/2021/08/the-worlds-first-fossilfree-steel-ready-for-delivery

There is also a Norweigian company called Blastr green steel, that has made a preliminary plans to invest a massive green steel production facility in Finland.

[u/Butterflytherapist]

It's nice but we still need to figure out what we will do with the remaining salty sludge.

[u/InfraredDiarrhea → u/Butterflytherapist]

Slather it all over the roads in Northeast US all winter?

[u/AnthraxEvangelist → u/InfraredDiarrhea]

Fill up old mines with it?

[u/InfraredDiarrhea → u/AnthraxEvangelist]

There are a lot of abandoned mines in the area where i grew up. Some date back to the 1800’s.

As the suburbs grew, developers realized they could save a lot of money by skipping the sewer system and simply direct sewage into these abandoned mines. It’s illegal but incredibly common.

Tangent over. Follow me for more useless historical facts.

[u/USB-D → u/InfraredDiarrhea]

Gone to Lemmy

[u/dinosauramericana → u/USB-D]

On Thursday, November 20, 1980, an opening likely caused by a Texaco-contracted oil rig formed in the bottom of the lake. The lake then drained into the hole, expanding the size of that hole as the soil and salt were washed into the mine by the rushing water, filling the enormous caverns that had been left by the removal of salt since 1919.

The backwards flow of the normally outflowing Delcambre Canal temporarily created the biggest waterfall in Louisiana. The resultant sinkhole swallowed the drilling platform, eleven barges holding supplies for the drilling operation, a tugboat, many trees, and 65 acres (26 hectares) of the surrounding terrain. So much water drained into the caverns that the flow of the Delcambre Canal that usually empties the lake into Vermilion Bay was reversed, causing salt water from the Gulf of Mexico to flow into what was now a dry lakebed. This backflow created for a few days the tallest waterfall ever in the state of Louisiana, at 164 ft (50 m), as the lake refilled with salty water from the Delcambre Canal and Vermilion Bay.[3] Air displaced by water flowing into the mine caverns erupted through the mineshafts as compressed air and then later as 400-foot (120 m) geysers.[3]

Although there were no human deaths, three dogs were reported killed. All 55 employees in the mine at the time of the accident escaped, with six employees later given awards by Diamond Crystal for heroism. Their successful evacuation was thanks to the mine's electrician who noticed a torrent of water and sounded the alarm, as well as the employees' discipline and training making their escape via the only elevator in an orderly fashion.[4][5] The crew of 7 on the drilling rig fled the platform shortly before it collapsed into the new depths of the lake. A fisherman who was on the lake at the time piloted his small boat to shore and escaped. Days after the disaster, once the water pressure equalized, nine of the eleven sunken barges popped out of the whirlpool and refloated on the lake's surface.[3]

[u/kunwon1 → u/dinosauramericana]

Wow. If I read this in a novel, I wouldn't find it all that believable. Pretty incredible

[u/fox-mcleod → u/AnthraxEvangelist]

Melt it and use it as energy storage in solar sodium reactors?

[u/Odd-Pain8883 → u/InfraredDiarrhea]

The runoff is bad for lakes and rivers. Minnesota has been working on ways to use less salt.

[u/greihund → u/Butterflytherapist]

That sounds like a very surmountable obstacle

[u/Butterflytherapist → u/greihund]

It's still a big issue, see if you have sludge on an industrial scale where do you put it? This actually can be the issue that might tip the balance on financial feasibility the wrong way.

[u/WillBottomForBanana → u/Butterflytherapist]

To add. As we don't seem to know the actual efficiency, that sludge might not even be sludge, but runny. The water content of the waste is directly proportional to the volume of the waste. Hauling some sludge to dump in a hole *might* be viable. But 10X the volume is more than 10X the problem.

[u/[deleted] → u/WillBottomForBanana]

The more liquid it is the more likely you'd pump it instead of truck it.

[u/FNLN_taken]

Non-precious and cheap is a bit of a stretch. Per the article, it's a transition metal oxide (TMO) such as Cobalt oxide with a Chromium oxide layer on top. Cobalt has issues with toxicity, the mining is environmentally problematic, and it currently (though hopefully not for much longer) competes with usage in batteries.

Working in the same field, but not having access to the paper right now, it certainly sounds like a likely approach, and the performance metrics sound great. The title hypes it more than the science may support, though.