What is This?
Helium Recovery Bags
By Amy Mast
Weíve all held onto a helium balloon and felt heliumís differences from the air around us – both its lightness and the speed at which it dissipates, invisible, if a balloon is popped or opened.
Take that same helium and cool it all the way down past 4.2 Kelvin. Thatís
-451.44 degrees Fahrenheit – about twice as cold as spending the night on the moon without a spacesuit, and three and a half times colder than the coldest recorded naturally occurring temperature on Earth.
The newest of the lab's helium recovery bags, used for recooling liquid helium for future use.
Eventually the helium is cooled all the way down to around 2 Kelvin, the temperature needed to operate the labís cold-hungry magnets. At this supercool temperature, helium becomes a liquid with no viscosity – meaning that theoretically, it can flow forever without stopping.
Without liquid helium, the most powerful superconducting magnets here at the lab would work about as well as your body without blood. Helium keeps superconducting and hybrid magnets cool enough to handle high magnetic fields, helping energy to move through the magnet without resistance or outside electricity. Without this simple ingredient, running these powerful research magnets simply wouldnít be possible.
Buying and storing this resource doesnít come cheap; the labís annual bill for liquid helium alone can reach $1 million. Thatís why the lab has adapted a system to recycle as much of the helium as possible, a move thatís both eco-friendly and cost-effective, and thatís where the giant balloon pictured comes in.
That giant balloon is one of the labís three helium recovery bags (and yes, theyíre all that big). The bags are basically high-tech recycling bins for helium ready to be re-cooled. Each one of these bags holds about 2,700 cubic feet of helium in gas form. From that huge space, the lab squeezes the gas into about a hundred liters of liquid helium – only enough to fill around 26 one-gallon milk jugs.