Helium is a very special gas among specialty gases: In addition to its best-known application as a lifting gas for balloons and airships, this noble gas has a whole range of other uses thanks to its special properties. For example, its high thermal conductivity makes it useful in many processes in welding and laser technology. “Its high diffusion capacity also makes it an ideal carrier gas in gas chromatography and the most commonly used tracer gas for leak detection,” explains Dr. Martin Dilla, Technology Manager for Specialty Gases at Messer SE & Co. KGaA.

Extremely cold
In its liquid state, helium has the lowest boiling point of any gas at 4.2 Kelvin or minus 269 degrees Celsius. Liquid helium is therefore the coldest liquid on earth. It is used as a cooling medium wherever extremely low temperatures of less than minus 200 degrees Celsius must be reached. This is the case, for example, in applications involving the generation of very strong magnetic fields using superconducting magnets. The most important technical applications are magnetic resonance imaging (MRI) in medicine, nuclear magnetic resonance spectroscopy (NMR), and other basic research applications. Helium is extracted from helium-rich natural gas sources, which are found in only a few locations worldwide. Messer uses several reliable sources worldwide to supply the European market. Messer operates a fleet of special, super-vacuum-insulated tank containers with a capacity of 40,000 liters each. These are used to transport the helium to our European filling plants in Mitry-Mory (France), Lenzburg (Switzerland), Gumpoldskirchen (Austria) and Pancevo (Serbia). In the filling plants Messer transfers the helium into smaller, also super-vacuum-insulated transport containers (Dewars) intended for customer supply. Gaseous helium is also filled here.

Ultra-pure gases and gas mixtures
Many technologies require pure gases or gas mixtures of defined composition and quality for safe and efficient operation. In insulating glass panes, the noble gas filling ensures improved heat and sound insulation. The highest demands are placed on gases when they are used to operate sensitive analytical instruments in environmental analysis, safety engineering, or quality assurance. In addition to carrier and operating gases for instruments and detectors, gas mixtures with a defined, precise composition are used in gas analysis to calibrate the devices. “There are only a few standard products here; Messer usually produces calibration gases individually according to customer specifications,” says Jerry Girardi, Sales Manager Specialty Gases at Messer in Switzerland. Due to the wide range of applications, there are very different requirements for the quality and delivery form of the gases. Messer offers a comprehensive range of standard products. The purities range from “technical” to “6.0 quality” with a purity of 99.9999 percent. Messer delivers the gases according to demand. The range extends from one-liter cans to cylinders and bundles to trailer or liquid supply.

Knowing how to do it...
The production of specialty gases consists of various steps, from cylinder pretreatment and filling technology to quality assurance analysis. In-depth expertise in all individual areas and reliable mastery of the entire process chain are essential. “Thanks to our many years of experience in local specialty gas plants, Messer is able to supply almost any technically feasible gas mixture in the desired composition and with the required accuracy,” says Dr. Frank Wallasch, Head of Specialty Gas Plants at Messer in Switzerland. Many calibration gases can optionally be supplied with a certificate from one of our accredited laboratories. However, special gases also require special expertise in their application. To ensure that the desired quality reaches the point of use from the storage tank, special precautions must be taken during installation. Not every fitting that has proven itself in technical applications can be used for specialty gases. Together with Spectron Gas Control System, a leading manufacturer of gas withdrawal equipment and gas supply systems, Messer offers suitable solutions for every application – from planning to complete installation.