Liquefied Petroleum Gas (LPG)

There are very few people who are not familiar with LPG or Liquid Petroleum Gas because most of the houses nowadays use LPG cylinders for cooking purposes and of late it is also being used as the fuel for vehicles but very few know about it in details. So here we would discuss the production, composition, uses and advantages that Liquid Petroleum Gas has and the potential uses that it might have in future. As an introduction let me tell you that LPG being a fossil fuel is non renewable and would be exhausted one day or the other like the other fossil fuels therefore it has to be used wisely.

Production and Composition

LPG is obtained as a by-product when refining crude oil or natural gas and is primarily composed of propane and butane with smaller amounts of propylene and butylenes. These belong to the category of hydrocarbons and Liquid Petroleum Gas has three or four carbon atoms and apart from these hydrocarbons there are negligible amounts of other hydrocarbons as well, which are present. You might be wondering that if this is the composition of LPG then what causes the characteristic odor that it has? Ethanethiol is combined wht it for its characteristic smell so that leaks can be detected easily. Though these are the standard components of Liquid Petroleum Gas, the percentage of each component differs from season to season. In summers the percentage of butane is more than propane and winters the percentage of propane is more than butane.

Due to its composition, which is rich in hydrocarbons, LPG evaporates at normal pressure and temperature; therefore it is canned under pressure. It can be moved in cans and utilized in places far from the place of production, which makes it quite popular. The temperature at which Liquid Petroleum Gas gets converted into the liquid form is called vapor pressure. To allow thermal expansion, the cans are not filled to the brim, approximately 15% to 20% is kept empty so that even if the volume of LPG increases it does not exert much pressure on the walls of the can.

Uses

LPG is used as a fuel in vehicles, for cooking and also as coolant of late so that the usage of Chlorofluorocarbons can be avoided which causes Ozone layer depletion. Hydrocarbons as coolants in air conditioners at home or in vehicles are a good option since they are more energy efficient and need less pressure but there is always the risk of fire since LPG is highly flammable. So it has to be used only when the risks of fire has been taken care of by decreasing the chances of leakage and accidents. LPG as a coolant is also very cheap and does not have the Greenhouse effect as well.

It is used as a cooking fuel in most of the houses of India and Brazil. It was quite popular as a cooking fuel in Hong Kong once upon a time but now the popularity has decreased. LPG is also used as fuel for vehicles since the emissions are less in case of LPG than petrol or diesel. But there are some disadvantages to it too. Some engines and machines need the lubrication of oil, which LPG fails to provide. The other disadvantage is that the energy density of petrol is less than that of petrol and diesel but the tax on LPG being less, it is cheaper.

Advantages and Disadvantages

There are many advantages of LPG like it is more environment friendly and the carbon content being lesser than other fuels the carbon blocking of engine parts in vehicles is also less. It also helps in increasing the longevity of the vehicle engine thus benefiting the owner of the vehicle.

The disadvantages of LPG are that it has a high risk factor due to its high flammability. Storage and safety should also be taken care of in the initial stages. LPG is also very volatile and high chances of it vaporizing also remains.