Methane CH4

Introduction of methane
Methane (CH4), or methane hydride, is the main constituent of natural gas: it is 3rd global energy source after oil and coal. Naturally present on earth, it is produced:

– From the fermentation of plants located in low oxygenated wetlands (swamps and marshlands…);

– From the digestive actions of animals (especially ruminants).

Methane can also be derived from the exploitation and burning of fossil fuels, as well as from the burial of waste. It is also the only hydrocarbon that can be obtained from a natural process.

The CH4 is odourless, colourless and lighter than air. Gaseous under normal temperature and pressure conditions. It can also present itself in a liquid state.

Use of methane
Methane is used in many industrial, domestic and agricultural sectors as a fuel or a combustible. It is then in the form of a marketable natural gas.

Methane is also used by the chemical industry to synthesise or manufacture many products: methanol, acetylene, ethanol, ammonia, and carbon black. It is also found in the manufacture of Geiger counters and as a trapping gas when mixed with argon.

Risks of methane
Methane is an extremely flammable gas. Indeed, it ignites very quickly on contact with a source of ignition and combustion. It also forms an explosive mixture with the air, and it can explode under the effect of heat. CH4 is also considered a greenhouse gas.

The health risks of methane
Although non-toxic, methane is likely, in high concentrations, to displace oxygen in poorly ventilated spaces and thus cause asphyxiation. Its flammable and explosive properties can also be responsible for severe burns and damage to the skin.