Hydrogen - SIAD Società Italiana Acetilene e Derivati
Hydrogen is the lightest of all gases.
Commonly found in nature in compounds with other elements, it is the most abundant element in the universe. Hydrogen is a component of water, minerals and acids, as well as an essential part of all hydrocarbons and essentially all other organic substances.73,9% of the mass of the visible universe is in the form of hydrogen.
Helium is the second most abundant element and it makes up about 24% of the mass.
Hydrogen and helium combined make up almost 98 % of the known universe mass.
Chemical formula: H2
Purity level: ≥ 99.8%
Relative density (air = 1): 0.07195
Aspect: colourless gas
Odour: odourless gas
Limit of flammability in air: 4 ÷ 75,6%
Hydrogen is used in several applications, which are listed below.
In the food industry, hydrogen is used:
- to hydrogenate liquid oils (such as soyabean, fish, cottonseed and corn), converting them to semisolid materials such as shortening, margarine and peanut butter.
In the chemical industry, hydrogen is used:
- to manufacture ammonia and methanol
- to hydrogenate non-edible oils for soaps, insulation, plastics, ointments and other specialty chemicals.
In metal production, hydrogen is used:
- to serve as a protective atmosphere in high-temperature operations such as stainless steel manufacturing.
In metal fabrication, hydrogen is used:
- commonly mixed with argon for welding austenitic stainless
- used to support plasma welding and cutting operations.
In power generation, hydrogen is used:
- to serve as a heat transfer medium for cooling high speed turbine generators
- to react with oxygen in the cooling water system of boiling water nuclear reactors to suppress intergranular stress corrosion cracking in the cooling system.
Other important applications of hydrogen are:
- in the pharmaceutical industry, to produce sorbitol used in cosmetics, adhesives and vitamins A and C
- in the electronics industry, to create specially controlled atmospheres in the production of semiconductor circuits
- in the petroleum industry, to enhance performance of petroleum products by removing organic sulphur from crude oil, as well as to convert heavy crude to lighter, easier to refine, and more marketable products.
To avoid this harmful effect, producers and customers should follow strict safety guidelines for storage and handling, and consult the hydrogen Material Safety Data Sheet.
Hydrogen and carbon dioxide production is carried out through steam reforming, a process based on the reaction between methane and water vapour.
The main steps of the process are listed below:
- compression, heating at 260 °C and purification of the methane
- demineralisation, disoxygenation, pH correction and water vaporization (at 200°C)
- introduction of methane and water vapour into the reactor tubes
- reaction between methane and water vapour at 800 °C, thanks to the presence of a nickel based catalyst
CH4 + 2H2O + Q = 4H2 + CO2
- recovery of carbon dioxide contained in the raw hydrogen through absorption in extraction tower and following liquefaction
- purification and compression at 200 bar of the hydrogen produced.
The recovery and storage of carbon dioxide combines economic advantages with environmental topics, thanks to the resulting reduction of Greenhouse Effect gases emissions in the atmosphere.
Hydrogen supply options and services available to SIAD customers include:
- transport in cylinders, cylinder packs or cylinder trucks
- design and installation of gas distribution systems
- supply of equipment for the correct use of the gas
- assistance and technical consultancy for the transport, distribution and application of the gas.
Hydrogen can also be supplied:
- with grades 3.5 - 4.5 - 5.5 - 6.0 purity
- in electric arc metal welding and cutting mixtures
- in special and in calibration mixtures with different composition upon request.