Liquefied Petroleum Gas
Liquefied Petroleum Gas (LPG)
Liquefied petroleum gas is a fuel gas made of petrol which contains a flammable mixture of hydrocarbon gases, most commonly propane (C3), butane (C4), and propylene. However, the latter two typically compose 5% or less of the mixture. LPG is used as a fuel gas in heating appliances, cooking equipment, and vehicles.
The term is widely used to describe two prominent members of a family of light hydrocarbons called “Natural Gas Liquids” (NGLs): propane (C3H8) and butane (C4H10).
The term “liquefied gas” may seem a contradiction in terms since all things in nature are either a liquid or a solid or a gas. Yet, liquidity is the unique character of LPG that makes it such a popular and widely used fuel. At normal temperature and pressure, LPG is gaseous. It changes to a liquid when subjected to modest pressure or cooling. In liquid form, the tank pressure is about twice the pressure in a normal truck tyre, which means it is very safe when properly handled.
Often, propane (C3) and butane (C4) will be mixed to get the best energy yields and properties. Propane’s lower boiling point is perfect for outdoor storage and it is primarily used for central heating, commercial applications, cooking and transport. Butane is mainly shipped in cylinders for portable applications such as mobile heaters or for leisure activities such as boats, caravans and barbecues. Butane can also be used as a propellant, refrigerant or to fuel welding torches.
LPG has two origins: approximately 60% is recovered during the extraction of natural gas and oil from the earth, and the remaining 40% is produced during the refining of crude oil.