Helium shortage puts lab vacuum technology under pressure

Vacuum technology keeps running into sustainability challenges. First there was a helium shortage. Then another. And another. In addition, the industry has been moving away from oil-sealed pumps and towards more sustainable methods. 

Helium shortages affect lab equipment

Helium shortages aren’t exactly new. The gas has been through four supply crunches since 2006, each driven by some combination of plant outages, demand spikes and the basic problem of having a nonrenewable resource concentrated in a handful of facilities. Labs have weathered price increases, rationed instrument time and grumbled about carrier gas costs before.

The fifth shortage is different in scale. Iranian strikes on Qatar’s Ras Laffan Industrial City in late February knocked roughly 30% of global helium production offline in a matter of days. Helium is separated as a byproduct during natural gas processing, so when QatarEnergy declared force majeure and halted LNG production, helium went with it. A second round of strikes in mid-March damaged two LNG trains and a gas-to-liquids facility, cutting helium exports by an additional 14% and pushing repairs out three to five years, according to QatarEnergy CEO Saad al-Kaabi. The Strait of Hormuz, through which virtually all of Qatar’s helium exports move, has been effectively closed to Western commercial shipping. Around 200 specialized cryogenic containers sit stranded near the Gulf, and because liquid helium boils off within roughly 45 days even in the best-insulated tanks, those containers represent a supply that is actively disappearing. Spot prices have roughly doubled since the crisis began.

Most of the headline coverage has focused on semiconductors and MRI machines. But the lab impact cuts across multiple instrument categories at once. Helium keeps Nuclear Magnetic Resonance (NMR) magnets cold enough to remain superconducting. It is the carrier gas in many gas chromatographs (GCs) and Gas Chromatography-Mass Spectrometry (GC-MS) workflows. And it is the standard tracer gas for vacuum leak detection in research (including in particle accelerators), pharmaceutical process systems (such as sterile drug packaging validation) and industrial manufacturing (including lithium-ion battery production).

Vacuum innovations eliminate oil backstreaming, reduce maintenance

In sensitive research, including fields such as semiconductor development and organic electronics, oil backstreaming can be a contamination risk. Dry pumps, which operate without fluid in the compression chamber, have become the standard as they eliminate the risk of backstreaming. These pumps also require less maintenance and produce less hazardous waste. Dry pumps include: dry screw pumps, which use intermeshing screws to compress and move gases; claw pumps, which offer contact-free operation; scroll pumps, which are more quiet and compact than some alternatives; and roots pumps, which are often used as booster pumps to enhance performance.

Multi-stage diaphragm pumps have pushed ultimate pressures down to 0.5 mbar and are almost entirely maintenance-free for up to 15,000 hours. These are centrifugal pumps with more than one impeller sharing the same shaft. Each stage includes an impeller and a diffuser. The fluid’s energy increases in each stage, causing a significant increase in pressure with little change to the flow rate. Multi-stage pumps can be horizontal, which is best for low vertical space applications and commonly used in HVAC systems, or vertical, which is better for deep well pumping and used in water treatment plants.

Variable speed drives (VSDs) have also started becoming a standard integration. These pumps monitor the chamber pressure and slow down the motor once the target vacuum pressure is reached. This can reduce energy consumption by 30% to 80%, as well as having cooler and quieter operation. VSDs can be adapted to blower or rotary vane vacuum pumps, although they may not be an economical option for smaller labs.