this post was submitted on 22 Jan 2024
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Chemistry

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[–] [email protected] 40 points 9 months ago (1 children)

I suspect that the frivolousness with which we currently release waste helium will look pretty stupid future generations. Wherever liquid helium is used as a coolant, we should be installing recovery systems to capture and recondense the helium. With the appropriate safety precautions, hydrogen can be used as a lifting gas for blimps and balloons. I can't think of any applications which require helium to be released into the atmosphere to float away into space forever.

[–] [email protected] 20 points 9 months ago* (last edited 9 months ago) (1 children)

You're forgetting that the act of science is political, in the sense that science must be conducted under the existing political framework. The very easy solution of recapturing helium is more expensive than just letting it float off.

[–] [email protected] 5 points 9 months ago

Good point. I suppose as the supply of helium dwindles, market forces will naturally make recapture systems more economical.

[–] [email protected] 21 points 9 months ago (3 children)

Helium is a byproduct of nuclear fusion, so in 50 years we should be rolling in it...

[–] [email protected] 15 points 9 months ago

Good idea but sadly not feasible

Relevant part (credit to [deleted] and u/chiagod):

Assuming D-T fusion, a single fusion event releases a 14.1MeV neutron and a 3.5MeV helium nucleus. Assuming you can absorb all this energy and you've got an efficient heat engine setup at around 50%, you'll get about 1.5x10^-12 J per fusion, so for a 1GW output you'll need 6.67x10^20 fusions per second. Say you have 1TWe (electric output) worth of fusion reactors worldwide (about half of current electricity generation), then you're producing 1000 times as much helium, or 6.67x10^23 atoms per second. About a mole each second, or 4 grams. This works out to 126 tons of helium a year, or about 1000m^3 per year of liquid helium. The US strategic helium reserve had a peak volume of about a billion m^3 . World consumption of helium is measured in tens of millions of m^3 per year so you'd be short by several orders of magnitude in the best case.

[–] [email protected] 8 points 9 months ago (1 children)

/s? I feel like that tech has been "20 years away" for like 50 years now...

[–] [email protected] 14 points 9 months ago (2 children)

This graph shows projections for how long it was predicted to take to develop fusion power depending on the funding. Graph showing how long it should take to develop fusion power. There are five lines, "maximum effective effort" ending in 1990, "accelerated" in 1993, "aggressive" in 1998, "moderate" in 2005, and "fusion never" which never ends. The line showing actual funding is below "fusion never".

[–] [email protected] 2 points 9 months ago (1 children)

So if a billionaire actually decided to fund it, we might have it? It appears that the actual amount of funding is below the "fusion never" line.

[–] [email protected] 3 points 9 months ago

They'd have to throw in like 10 billion a year for over a decade, so we probably need a couple of the worlds richest billionaires

[–] [email protected] 1 points 9 months ago

Checks out.

[–] [email protected] 3 points 9 months ago

Helium is found adjacent to natural gas deposits which have formed in rock with a high uranium content. Over time, the uranium decays, and helium atoms are part of the result of that decay. Almost all of the world's helium comes from an area around San Antonio, Texas.

[–] [email protected] 20 points 9 months ago (3 children)

Can we please either stop using floating balloons or replace with hydrogen already, sooo stupid.

[–] [email protected] 13 points 9 months ago (2 children)

Hydrogen balloons are dangerous. I say this as someone who handles them relatively often. One blast can seriously damage your hearing if you are standing next to it. And they explode easily, too.

[–] [email protected] 2 points 9 months ago

Fair enough, I stand corrected. Air it is...

[–] [email protected] 1 points 9 months ago

Macy's Thanksgiving Day parade might actually become interesting

[–] [email protected] 6 points 9 months ago (1 children)

Not possible for certain things, plus hydrogen in balloons is dangerous.

It's needed to super cool magnets in NMR (and MRI), and it's heavily used as a carrier gas in GC (where hydrogen is used as the flame gas).

Many GC methods could have helium replaced with nitrogen, but the difference in gas performance means updating every method with tedious work.

For NMR, there is no alternative, just varying degrees of effectiveness in how you use helium.

[–] [email protected] 4 points 9 months ago (1 children)

I was specifically talking about novelty balloons. Personally I think the danger is overblown in most situations, small rising pop (perhaps of flame), but if you have a problem with that, use air... with the goal of saving it for more important uses, like some of your examples. Blimps are another egregious waste, especially if usage scales up they need to be engineered for sustainable hydrogen.

[–] [email protected] 2 points 9 months ago

Someone needs to make a "balloon" you fill with normal air and then has a rechargable battery and 4 drone propellers to make it float up.

The balloon lasts much longer than a helium balloon, only downside is you have to charge it and it's noisy.

[–] [email protected] 1 points 9 months ago

The Hindenburg was a giant zeppelin 🎶 It's engineers made a minor oversight

Before filling it with explosive gas they should have fixed the "no smoking" light

[–] [email protected] 17 points 9 months ago (1 children)

Yeah got it, but what if we use it to fill garbage to make it float for a day?

[–] [email protected] 2 points 9 months ago

Nah. Let's inhale it to sound funny.

[–] [email protected] 8 points 9 months ago (1 children)

Lithium fission is being explored for subcritical reactors. The fission of lithium ions by bombarding them with neutrons results in excess energy, tritium atoms, and helium atoms.

It would be an amazing thing if widespread energy generation via subcritical fission of lithium also helped solve the “finite helium” problem.

Imagine a world where old lithium batteries can be recycled and create H^3 and He^4 and also generate clean energy.

[–] [email protected] 4 points 9 months ago (1 children)

We can make helium from anything that undergoes beta decay

[–] [email protected] 3 points 9 months ago (1 children)

Beta decay or alpha decay?

[–] [email protected] 7 points 9 months ago

Oh wait you’re right, I said the wrong one.

[–] [email protected] 1 points 9 months ago* (last edited 9 months ago)

You can make it in unlimited abundance in fusion reactors. The difficulty in fusion wasn't producing elements, it was doing so profitably, and now even that's starting to crack. You can even make a novelty fusion reactor on your desk if you wanted to, it isn't exactly hard.