Liquid petroleum gas (LPG, and sometimes called propane) is often confused with LNG and vice versa. They are not the same and the differences are significant. LPG is composed primarily of propane (upwards to 95%) and smaller quantities of butane. LPG can be stored as a liquid in tanks by applying pressure alone. LPG is the “bottled gas” often found under BBQ grills. LPG has been used as fuel in light duty vehicles for many years.
It is important to understand the differences between Liquefied Natural Gas (LNG), Compressed Natural Gas (CNG), Natural Gas Liquids (NGL), Liquefied Petroleum Gas (LPG), and Gas to Liquids (GTL)
LNG is made up of mostly methane – the liquefaction process requires the removal of the non-methane components like carbon dioxide, water, butane, pentane and heavier components from the produced natural gas
CNG is natural gas that is pressurized and stored in welding bottle-like tanks at pressures up to 3,600 psig
NGLs are made up mostly of molecules that are heavier than methane like ethane, propane, and butane
LPG is a mixture of propane and butane in a liquid state at room temperatures
GTL refers to the conversion of natural gas to products like methanol, diethyl ether (DME), middle distillates (diesel and jet fuel), specialty chemicals and waxes