Helium gas was first used for filling balloons, but has since become vital in other applications, with worldwide production currently sitting at around 4,500 tons annually – a figure only set to rise.
Its properties are that of extremes; it is less soluble in water than any other gas, and possesses the lowest melting and boiling points of any element, making it the coldest element known to man.
Furthermore, though it occurs very infrequently in air, at approximately five parts per billion, it is the most abundant element in the universe, constituting 25% of the atmosphere.
Helium (He) also shares characteristics with its periodic group; namely its inertness, low melting and boiling points and non-toxic qualities. Similarly to xenon and krypton, it also benefits from extremely high thermal conductivity. However, unlike its sibling elements, most helium is obtained through natural gas in which it occurs at a frequency of 7%.
More than just hot air
Due to its wide scope of properties, helium perhaps unsurprisingly answers numerous applications. The most renowned use is to inflate balloons, as was seen last month in the Delhi Commonwealth Games aerostat.
Further, it is also used in welding and cutting, fibre-optics, electronics, aerospace applications, leak-testing, deep-sea diving, cooling superconductive magnets, as well as being essential in the production of silicon wafers and in areas of particle research – for instance in CERN’s Large Hadron Collider.
But by far the most significant application comes from the manufacture and operation of magnetic resonance imaging (MRI) scanners – in which liquid helium cools the superconductive magnets that generate high resolution images of the body. This constitutes 22% of its global demand.
The Linde Group, a longstanding supplier of noble gases, told gasworld of the rising demand for helium due to concurrent increased demand in MRI, electronics, semiconductors, liquid crystal displays and fibre-optics. The global firm anticipates particular growth for the gas in China, India, Korea, Taiwan and the Middle East.
Dan Baciu, Linde Gas’ Head of Global Helium Business Development, explained how this demand has incited occasional concern about helium price increases and potential shortages. “In many applications, helium is irreplaceable with any other element, so inevitably these customers will be affected.”
He continued, “The BLM reserve, traditionally the least costly helium source in the world, might be exhausted in 10 to 15 years’ time. This will have to be replaced with investments outside the USA which will push costs up based on increased expectation of higher return on investments and via increases in the price of feed-gas, by the owners of the natural gas resources who have come to recognise the helium by-product as a lucrative business opportunity. In turn, helium suppliers will attempt to pass on these cost increases to their customers.”
However, according to Baciu, the industry is prepared and will retaliate with recycling and substitution. He elucidated, “We’re going to see increasing demand for recapturing, recycling and conservation of helium and there is already improved MRI technology that conserves liquid helium by slowing down its evaporation during the operation of the MRI.”
“Wherever possible, manufacturers will also start investigating substituting helium with other elements. For instance, argon is just as inert as helium and a significant number of electronic manufacturers have found that using a mix of helium and argon works well and provides a significant cost advantage.”
Baciu concluded, “Helium obviously remains ideal, but with economic concerns, manufacturers might choose an alternative in order to lower their operating costs and become less dependent on helium.”