Liquefied Petroleum Gas (LPG) refers to the by-product obtained by the refinery in the catalytic cracking and pyrolysis of crude oil. It is a kind of clean-burning fossil fuel that can be used to drive turbine or internal combustion engines. It is a mixture of propane and butane, usually accompanied by a small amount of propylene and butane. A strong odorant ethyl mercaptan are added into liquefied petroleum gas, so the LPG leakage can easily be found. LPG is mainly used as petrochemical feedstock for ethylene cracking of hydrocarbons or steam reforming to syngas, and used as fuel for industrial, civil and power generation.