Fuel gas

Fuel gas is one of a number of fuels that under ordinary conditions are gaseous. Most fuel gases are composed of hydrocarbons (such as methane and propane), hydrogen, carbon monoxide, or mixtures thereof. Such gases are sources of energy that can be readily transmitted and distributed through pipes.

Fuel gas is contrasted with liquid fuels and solid fuels, although some fuel gases are liquefied for storage or transport (for example, autogas and liquified petroleum gas). While their gaseous nature has advantages, avoiding the difficulty of transporting solid fuel and the dangers of spillage inherent in liquid fuels, it also has limitations. It is possible for a fuel gas to be undetected and cause a gas explosion. For this reason, odorizers are added to most fuel gases. The most common type of fuel gas in current use is natural gas.

There are two broad classes of fuel gases, based not on their chemical composition, but their source and the way they are produced: those found naturally, and those manufactured from other materials.

Manufactured fuel gases are those produced by chemical transformations of solids, liquids, or other gases. When obtained from solids, the conversion is referred to as gasification and the facility is known as a gasworks.

Manufactured fuel gases include:

The coal gas made by the pyrolysis of coal contains impurities such a tar, ammonia and hydrogen sulfide. These must be removed and a substantial amount of plant may be required to do this.

In the 20th century, natural gas, composed primarily of methane, became the dominant source of fuel gas, as instead of having to be manufactured in various processes, it could be extracted from deposits in the earth. Natural gas may be combined with hydrogen to form a mixture known as HCNG.

Additional fuel gases obtained from natural gas or petroleum: