The merger between Linde and BOC has also propelled The Linde Group to the forefront of the promising global market for the rare noble gas helium. Linde holds a 51 percent stake in the helium plant in Skikda, Algeria, and, with local partner Sonatrach, manages two joint venture companies – Helison Production Ltd. and Helison Marketing Ltd. BOC has been one of the world’s leading helium suppliers for decades, a role consolidated by its purchase in 1977 of the Otis helium facility in Kansas, USA, which dates back to 1965. This facility now meets 16 percent of the global demand for helium. 85 percent of the gas is sourced in the USA, with the remainder coming from Algeria, Poland, Qatar and Russia.

Although helium is one of the universe’s most abundant elements, it is very rare on earth. In the earth’s atmosphere, the concentration of helium by volume is only 0.0005, which is much too low for extraction to be viable. However, helium can be extracted from natural gas. Through the disintegration of substances such as uranium and radium, it can reach concentrations of between 0.2 and five percent by volume.

Helium is extracted from natural gas by means of liquefaction. With a temperature of –268.92 degrees Celsius and a pressure of 1,013 bar, this liquid gas is then purified and stored or transported in special containers.

In past decades, helium was mainly used as a lifting agent for balloons and airships, but it now plays a crucial role in key modern technologies. Unique properties such as an extremely low level of reactivity, a low boiling point (–269 degrees Celsius), high thermal conductivity and high diffusibility make pure helium and helium mixtures ideal for a wide range of applications. These include welding and cutting (ships, space systems and aluminium frames for example), laser and measurement systems, fibre-optic cables and semiconductors and artificial atmospheres with oxygen. Helium is also used as a cooling agent in nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging (MRI) (Glossary) systems. Due to the sheer range of possible applications, annual sales volumes far exceed 100 million cubic metres.