March 30, 2012
Somebody better warn Goodyear, and, for that matter, all the blimp operators and welders and hospitals and scientists who use helium. We’re rapidly running out of the stuff, and they’re not making any more of it. The simple fact is that you can’t make helium. We get it from natural gas fields in Kansas, Texas and Oklahoma, where it makes up less than 10 percent of the total volume of gas. The natural gas mixture is super-cooled to separate out the helium, methane and other gases in a process called fractional distillation. It’s present in the atmosphere, but very diffuse.
Helium was created underground eons ago as radioactive rock underwent natural decay, spitting out alpha particles, which, being made up of two protons and two neutrons, are identical to the helium nucleus. It just so happened that there was a lot of radioactive rock in the gas fields of the Midwest – lucky for us. Anyway, add a couple electrons, which are all over the place, and you can float your blimp.
Oddly, despite its rarity here on earth, where the United States produces 90 percent of the world’s supply, helium as an element makes up nearly a quarter of the mass of the universe, being a major component of stars like our own sun, where it’s created by fusion of two hydrogen atoms – your basic H bomb principle. And there are tons of it in the lunar soil in the form of helium-3, an isotope that’s one key to artificial fusion power.
The Hindenburg had to use flammable hydrogen because the U.S. government considered inert helium to be a strategic material. No helium for Germany. So the Hindenburg caught fire and was destroyed. At first, the safety of helium was most valued for airships, but today it’s far more valuable in science, medicine and industry. Liquid helium cools medical scanners, space telescopes, radiation detectors and other instruments that require a cryogenic cooler. An electric arc welding technique that displaces air as the weld is formed uses a stream of helium as the means of shielding the weld. It’s the “IG” in TIG welding, which stands for Tungsten Inert Gas.
So what to do? Higher prices will persuade users not to waste helium on party balloons, and Goodyear already recycles and purifies it whenever it deflates an old blimp. Right now, the U.S. reserves are being sold off at a low price. For flotation of airships, one possibility might be to add some hydrogen to a blend of the buoyant gas the way they blend biofuel into Jet A, but that will take some experimentation to determine its safety. We can only hope they get busy, because some forecasts say we’ll be out of helium in 10 years or so.