Applications
Chemical industry
The chemical industry employs all major industrial gases as a raw material or for inerting mainly nitrogen or argon.
Cutting and welding
Cutting and welding are long established techniques using the gases acetylene, propane, mixtures of fuel gases and oxygen. For MIG (metal inert gas) welding, argon, helium, carbon dioxide and oxygen and mixtures of these are used. TIG (tungsten inert gas) welding uses argon and helium and, occasionally, hydrogen.
Environmental protection
Liquid nitrogen is vital in recycling plastics, packaging and scrap tyres as well as material separation of electric motors, batteries and cable waste. Oxygen reduces emissions by treating toxic wastes that are not readily combustible and destroying toxic gases. It can also help treat contaminated soil through stripping and biological cleaning without replacing the soil.
Food and beverage gases
Many of the improvements in food safety and quality have been achieved using industrial gases. Liquid nitrogen and carbon dioxide high quality product freezing. These gases are also used to maintain accurate low temperatures for food distribution. Gas mixtures preserve the freshness of packaged meat, seafood ready to use vegetables, cakes, etc. Gas mixtures extend the storage life of fresh fruit.
Carbon dioxide is very important in the beverage industry (mineral water, soft drinks, beer and wine) for carbonation and with nitrogen for bottling processes and inerting. Nitrogen is used to inflate packages of snack food to prevent damage and preserve freshness.
Gases for breathing
Divers, who operate at depths of 300 m and more, depend on oxygen / helium – mixtures as a breathing gas.
Oxygen will be used in airplanes in case of cabin pressure loss for both pilots and passengers at 5000 metre plus altitudes.
Gases for safety and inerting
Nitrogen, carbon dioxide, argon and mixtures of these gases are inert and prevent the formation of explosive or oxidizing atmospheres. Carbon dioxide, argon and their mixtures are employed for fire fighting when water cannot be used. Nitrogen and carbon dioxide are used to inert grain silos. Liquid nitrogen is employed for ground freezing, partial freezing of liquids in pipelines for repairs and as emergency cooling. Nitrogen is used for safety inerting and pressure build up in the recovery of oil and gas wells.
Glass, ceramics, other minerals
Oxygen can increase the production capacity of furnaces, nitrogen and argon are used as inert gases to prevent oxidation, argon and krypton can optimise the insulation in double or triple glazing and the tinted glass in buildings is made by gas plasmas in large vacuum chambers using nitrogen to protect the process against oxidation.
Hydrogen energy
Hydrogen, constituent in water and all organic matter, is the most abundant element in the universe. It is a feedstock, but it can also be an energy carrier. Hydrogen can be used for reduction of GHG (Greenhouse gases) and it can also become an alternative to petroleum based fuels. In recent years research into hydrogen as energy carrier has made tremendous progress. Hydrogen is renewable, abundant, efficient, and unlike other alternative fuels, produces zero emissions because it combusts to produce only water. With hydrogen, it is possible to generate electricity both for stationary and portable applications with the possibility to store it on a long-term basis. Moreover hydrogen can be used as a fuel on board of a new generation of hydrogen powered cars which now can achieve performances in line with the traditionally expected performances of cars equipped with conventional engines.
Medicinal gases
Nitrous oxide and oxygen have been used for more than 100 years. Other gases, such as helium, are used in sophisticated techniques such as MRI (magnetic resonance imaging), keyhole surgery and PET (positron emission tomography). Carbon dioxide is employed in bath therapy and for cryo surgery, liquid nitrogen is used for cryo surgery, rheumatic therapy and cryo conservation and nitric oxide for patients with pulmonary failure.
Metallurgy
Large quantities of oxygen, nitrogen and argon are used in the steel and metal industry. Oxygen is used as a booster and reaction medium for combustion processes for steel and cast iron and can reduce dust emissions and pollutants in flue gases. Argon is used as an inert gas for cleaning, homogenising and degassing in steel production and nitrogen and argon as inert gases in the non-ferrous metal industry. Reactive gases produce special metallurgical effects.
Rubber, plastics, paint
Liquid nitrogen is employed in the cold grinding of thermoplastics, hardening and deflashing rubber, which is only possible at very low temperatures, and for cooling to increase quality and production capacity e.g. in blow moulding and synthetic resins. Fluorine mixtures are used for surface treatment of plastic containers and oxygen (ozone) increases the coating quality of plastics.
Semiconductor industry
Nitrogen, oxygen, argon, hydrogen and mixtures are required as high purity gases in microchip production. The delivery of these products at 99.999999% purity (and even higher) demands high standards in distribution tankers, storage and pipework and has led to significant advances in analysing equipment.
Water treatment
High inorganic residues and high organic load in drinking water can be corrected with oxygen and ozone. Carbon dioxide controls hardness and, with hydrogen, reduces high nitrate values. For sewage water treatment, oxygen and ozone are used for biological reaction and carbon dioxide for neutralisation. Ground water, process water, cooling water and fish farming problems can be resolved using oxygen.