Brigitte Prat runs Lulu’s Cuts & Toys, a popular hair salon for kids in Brooklyn’s Park Slope neighborhood. She rewards new bobs with pretty orange balloons, but the practice is growing costly. “I used to put one on every arm and every stroller that rolled through my store, but now I keep them behind the counter,” she says. “I am paying an arm and a leg for my helium.”
Prat is far from alone. The U.S. is running out of helium, ironically the second most abundant element in the universe after hydrogen. The shortage is no laughing matter for makers of magnetic resonance machines, who use it to cool down powerful superconducting magnets.
GE, for example, is investing $17 million in a new plant in Florence, SC, to recycle helium used for cooling magnets for MR machines. Some of them use as much as 10,000 liters of liquid helium. That’s why engineers at GE Global Research are also designing new machines that will need as little as 10 liters. “When you power up a super-cooled magnet, it can produce the same magnetic field for a thousand years with no more power required,” says MR engineer and inventor Trifon Laskaris.
Robot welders work with steady precision to create a continuous seal on the vacuum vessel foe an MRI magnet. Top image: A worker injects helium into the finished magnet, the final step of the manufacturing process. Image credit: @seenewphoto
GE Healthcare uses about 5.5 million liters of helium a year at the Florence plant. It uses another 6 million liters a year to service and top off MRI systems at hospitals and clinics.
Helium cools the machines’ magnets to minus 452 degrees Fahrenheit (minus 269 Celsius), near absolute zero. At that temperature they lose all electrical resistance and become superconductive.
Workers pump the helium inside a sealed vacuum system surrounding the magnets. The Florence plant is using robotic welders to manufacture the helium vessels (see pictures above and below). The finished product can maintain a better vacuum than outer space.
The current helium shortage is partially self-inflicted. Helium is a waste product of helium-rich natural gas located in deposits stretching from Texas to Montana. In 1925, the U.S. government got into the helium business to secure supplies for defense needs. Helium-filled airships traveled as escorts with supply convoys to Europe during World War II, and demand grew even more during the Cold War and the space race.
Each 3 Tesla MRI magnet contains over 125 miles of copper and niobium titanium wiring. This wiring has enough strength to lift a car. Image credit: @seenewphoto.
After the fall of the Soviet Union, the Helium Privatization Act of 1996 got the government out of the business of producing the gas. But sales from the huge U.S. helium reserve stored in porous rock deep underneath Amarillo, Texas, kept down prices and gave private producers few incentives to enter the market. The shortage followed.
Last year, Congress passed a new law designed to ease the helium shortage, but businesses like GE are not taking chances.
Recycling and innovation will help keep helium from becoming a hot commodity. They might also preserve Prat’s orange balloons on Brooklyn streets.