We all learn about helium as little kids, but where does it come from? How is helium made? We’ll explain the process in simple terms.
Natural helium stores
First off, helium is like gold in the sense that it cannot be “made” by humans. It can only be harvested, collected, extracted, etc. from natural deposits in the earth. So when asking, “How is helium made?” understand that it’s more appropriate to phrase it like this: “How is helium produced?”
Helium is created underground (on earth). It is a natural byproduct of the radioactive decay of elements like uranium. As you might imagine, this process takes an exhaustively long time.
A lot of helium gets trapped in and under layers of rock, but a lot of it seeps up through the earth’s crust and escapes into space as well.
The escaping helium is gone forever. The helium that remains trapped most often mixes with natural gas. This is the helium that gets extracted.
Extracting trace amounts of helium
Natural gas does not come out of the earth in it’s purified fuel form that we may be accustomed to. It’s filled with impurities which have to be removed in order to refine it into the end product. One of these impurities is helium.
Here is how we get the helium out of the natural gas mixture:
1. Pretreat the natural gas
In the typical method, the trace amounts of helium are separated from the natural gas through a cryogenic piping system.
The natural gas is first pressurized, scrubbed, and then passed through a sieve. (Think of a pasta strainer, but with holes at the molecular level rather than noodle level.) This process is to remove water vapor and solids that could freeze and clog the pipes.
2. Separate the helium
In this stage, the natural gas is distilled in several different steps so that its major components can be extracted.
Basically, nitrogen and methane are separated out in a series of compressions, expansions, and evaporations using both heating and cooling, which produces mixtures of both compressed liquids and expanded gases. (You can read the technicalities of this process here if you’re the sciency type)
When the nitrogen and methane are mostly removed, the gas that is left behind is crude helium.
However, crude helium is still only around 50% pure. The rest is remnant methane and nitrogen, neon, and some hydrogen. In order to be commercially viable, the helium must reach purities of at least 99.99%.
3. Purify the helium
The crude helium now enters a series of separation processes itself in order to remove the impurities.
It’s first cooled to -315°F. This condenses any remnant methane and nitrogen gases into liquids, which can simply be poured out like coffee down a drain.
Now the helium purity is closer to 90%, but still not pure enough. So, oxygen is added to the helium and they heat it up.
When the helium-oxygen gets nice and hot, any trace hydrogen left in the helium gas will react with the oxygen and turn into water vapor. Once the vapor forms, the mixture can be cooled back down and the water drained out.
Finally, the helium is pressurized and pumped into specialized containers that are filled with extremely fine-poured particles, which trap and collect any remaining impurities in the helium gas. It’s not unlike a carbon water purifier you might attach to your faucet at home.
The helium is purged back out and then reintroduced into another of these filtering containers, and the process repeats several times until all the little impure particles are trapped and the the remaining helium is 99.99% pure (or higher).
Bonus
There can also be trace amounts of helium in the air (some places more than others) that can be “caught” before it escapes our atmosphere. The way to do it is by actually liquefying the air, collecting it, and going through similar separations processes. However, because this is such an expensive way to reclaim such small amounts of helium versus natural gas refining, it’s very rarely done.
A new appreciation for helium
So there you have it. You now know how helium is “made.” It sounds like a whole heck of a lot of work to float some party balloons, doesn’t it? Well, you’re darn tootin’ it’s a lot of work, but helium has a plethora of daily uses.
Helium is actually used for a wide variety of applications, industries, and purposes, in addition to entertainment and balloons. If you’re interested, here’s a quick list of 15 ways helium is needed for products and services that you see or use just about every single day. It’ll surprise you!
