I'd like to point out that helium is used in science for many applications. For example, the superconducting magnets in MRI machines are cooled by helium. Since it is not renewable and escapes from the atmosphere easily, we should conserve it, and probably not use it for party balloons.
I was curious about this so given some numbers I found on the internet, an average MRI machine has about 1700 liters of liquid helium capacity and loses 48% of its helium over the course of a year.
1 liter of liquid helium expands to .74m^3 of gaseous helium at room temperature. A 16" party balloon has .042 m^3 of space, so requires .05 liters of liquid helium.
So one MRI machine can hold ~30,000 balloons worth of helium and leaks about 39 balloons per day.
Note: This is not to suggest helium that is used for balloons is being redirected from MRI machines. As the article states, helium is captured almost exclusively as a byproduct of natural gas mining and any excess helium not worth capturing is just vented off. Reducing demand for helium by eliminating party balloons would have no affect on the amount of helium that is released from the ground.
Well, sorta. If the helium is worth a lot, you’ll try to drill/pump the wells that have a lot of it.
If/when it’s not, you might slow down on the helium-rich gas fields and bulk up on the 100% hydrocarbon fields, especially if natural gas is selling for a lot.
Helium is semi renewable. More is constantly created by underground decay of radioactive isotopes. But we're probably using it up faster.
Regardless of helium supplies, party balloons are problematic because they tend to escape and contaminate the environment with rubber and plastic. I frequently see empty mylar balloons floating in the ocean.
Oil and Helium are both replaced on geologic timescales their effectively a constant in terms of human lifespans.
You can estimate decay rates from net heat generated by the earth, but only a tiny fraction of the helium produced is close enough to the surface to be captured by us. On top of this helium is really good at escaping confinement so you need very specific geological formations to end up with significant quantities.
Thanks for the correction. I ignored decay products because it is a very small rate. Anyway, if we're invoking physics, the Sun harbors a very large reservoir of He. ;-)
I wonder if that's going to continue to be the case with MRI machines? Some newer high-temperature superconductors (for instance ReBCO tape) don't need to be kept quite that cold. Eventually I'd expect machines based on newer materials to replace the old machines, unless there's some compelling reason why the helium-cooled machines are fundamentally better.
(I do agree we should conserve it rather than use it for frivolous purposes.)
I suspect the real value proposition from that MIT fusion spinoff is not fusion reactors, but high Tc superconducting magnets for non-fusion applications like MRI (or, perhaps, hybrid electric aircraft). These could be cooled with neon instead of helium, and neon is available forever as a byproduct of air separation plants.
Interestingly enough, Google told me there are only 14 gasses that are lighter than air. They are:
* acetylene
* ammonia
* carbon monoxide
* diborane
* ethylene
* helium
* hydrogen
* hydrogen cyanide
* hydrogen fluoride
* methane
* methyl lithium
* neon
* nitrogen
* water vapor
Wiki lists most of them at https://en.wikipedia.org/wiki/Lifting_gas , although it leaves out ethylene, methyl lithium, and diborane for some reason. It also doesn't explicitly list carbon monoxide, but talks about it under "coal gas."
Of those, only hydrogen and helium are even vaguely suitable for party balloons, due primarily to their nasty chemical properties and/or expense.
The third sentence of the article: "Only certain lighter than air gases are suitable as lifting gases."
Diborane, among other things, autoignites in an oxygen atmosphere at 38C, and also burns on contact with water. It manages a rare NFPA fire diamond of 4 4 3.
It is tough to be a less practical lifting gas than hydrogen cyanide or hydrogen fluoride, but I think diborane manages it.
>Because of the exothermicity of its reaction with oxygen, diborane has been tested as a rocket propellant.[32] ... Diborane is pyrophoric gas. Commercially available adducts are typically used instead ... The toxic effects of diborane are mitigated because the compound is so unstable in air. The toxicity toward laboratory rats has been investigated.[38]
Note that hydrogen fluoride was the first thing featured on that column, even before the name of the series settled down: https://archive.md/gX3xF
> HF has actually been used right out of the cylinder for a long time in Merrifield peptide synthesizers. It’s the traditional way to cleave the peptide off the resin at the final step, so there are actually a lot of people who’ve used the stuff. But it’s in a dedicated apparatus that is (that had better be) well sealed, and people treat it with due respect. At a former employer of mine, there was an accident with one of these machines right before I joined the company. The shout “HF LEAK!” went out into the halls, and I’m told that the whole area set a never-to-be-equaled evacuation record.
By the fire diamond metric, HF is relatively tame, at 4 0 1, except that anything with a health rating of 4 ("very short exposure could cause death or major residual injury") is unsuitable for most purposes. So you can't set it on fire. Doesn't matter.
Thanks for that link, I really do enjoy his writing. "Relatively tame" isn't something I expect to see with a health rating of 4, but I suppose it's an accurate statement when you're talking 4x3 ratings.
Well, balloons filled with pure hydrogen tend to go poof, but fill them with a stoichiometric mixture of hydrogen and oxygen (like the output of a water electrolysis cell) and the have a pretty powerful explosion.
I wonder if it's really that risky to use hydrogen for party balloons that will be outdoors. Weather balloons and other un-manned lifting platforms already use it.
Methane, nitrogen, and neon wouldn't be too bad from a toxicity perspective, though neon would be expensive, and nitrogen isn't all that great in terms of density.
While methane is a greenhouse gas, as the article mentions, the amount used for balloons under any realistic scenario is going to be dwarfed by the megatons of methane that enter the atmosphere from natural processes (and, of course, natural gas is mostly methane). It's also dirt-cheap.
While I completely agree that waste is inexcusable and helium is really important there are many grades of helium and they are basically all industrial biproducts. The stuff at parties is mostly air and unsuitable for most scientific applications (checking leaks with a mass spec in a vacuum system is one of the few).
Even the high grade welding/scientific stuff is little more than a biproduct of natural gas extraction. The value of helium recovered from a well is essentially nil compared to the natural gas, so it’s conservation is not really possible since there is no real market force regulating supply (we would basically need to restrict natural gas consumption to nil, which is a good idea long term but not really feasible for civilization at the current stage.
It seems to me that the market would eventually correct this. If it cost $100 to fill a party balloon with helium, people would stop filling party balloons with helium and people working in scientific applications would have plenty of helium at that price point.
