What is LPG? How is LPG Produced?
LPG is primarily the flammable hydrocarbon gases Propane and Butane used as fuel for gas heaters, cookers, and vehicles. It is also used indoors in homes and outdoors for BBQs, camp stoves and many other applications.
There are a number of fuel gases that fall under the LPG products label, including propane, butane (n-butane) and isobutane (i-butane), as well as mixtures of these gases. They are also referred to as natural gas liquids or NGLs.
LPG gas is colourless and odourless until an odorant is added for safety reasons. When compressed, it takes liquid form, and when burnt it has a high energy content. It can be conveniently stored and transported and is an excellent fuel for heating, cooking, and many other applications.
In different countries, the LPG gases supplied can be propane, butane or propane-butane blends.
In Australia, LPG is just propane. To explain LPG, propane is LPG but not all LPG is propane.
What is LPG – Explain LPG – Summary:
LPG – Liquefied petroleum gas or liquid petroleum gas (LP gas) – is primarily the flammable hydrocarbon gases propane and butane used as fuel for gas heaters, cookers and LPG vehicles. LPG is also referred to as “bottled gas”.
To explain LPG, there are a number of fuel gases that fall under the LPG products label, including propane, butane (n-butane) and isobutane (i-butane), as well as mixtures of these gases and are also referred to as natural gas liquids – NGL.
LPG in Summary:
1. LPG (or LP Gas) is the acronym for Liquefied Petroleum Gas or Liquid Petroleum Gas.
2. LPG products are made up of a group of flammable hydrocarbon gases that are liquefied through pressurisation and commonly used as fuel.
3. LPG comes from natural gas processing and petroleum refining.
4. LPG gases can all be compressed into liquid at relatively low pressures.
5. LPG is frequently used for fuel as LPG heating gases, cooking, hot water and vehicles, as well as for refrigerants, aerosol propellants and petrochemical feedstock.
6. LPG is generally stored, as a liquid, in steel vessels ranging from small BBQ gas bottles to larger gas cylinders and LPG storage tanks.
7. LPG is mixture of flammable hydrocarbon gases that include propane, butane, isobutane and mixtures of the three LPG gases.
The following short video (8:29) explains all of the basics of LPG…
LPG Attributes Table
| LPG Attributes | Propane | Butane |
| Chemical Formula | C3H8 | C4H10 |
| Energy Content: MJ/m3 | 95.8 | 111.4 |
| Energy Content: MJ/kg | 49.58 | 47.39 |
| Energy Content: MJ/L | 25.3 | 27.5 |
| Boiling Temp: Cº | -42 | -0.4 |
| Pressure @ 21ºC: kPa | 858.7 | 215.1 |
| Flame Temp: Cº | 1967 | 1970 |
| Expansion: m3/L | 0.270 | 0.235 |
| Gas Volume: m3/kg | 0.540 | 0.405 |
| Relative Density: H2O | 0.51 | 0.58 |
| Relative Density: air | 1.53 | 2.00 |
| L per kg | 1.96 | 1.724 |
| kg per L | 0.51 | 0.58 |
| Specific Gravity @ 25ºC | 1.55 | 2.07 |
| Density @ 15ºC: kg/m3 | 1.899 | 2.544 |
Note: Some numbers have been rounded.
What does LPG stand for?
LPG is the acronym for Liquefied Petroleum Gas or Liquid Petroleum Gas.
LPG Gas is the RAS syndrome equivalent, where RAS stands for redundant acronym syndrome.
Other names for LPG include bottled gas, LP gas, Autogas (when used as vehicle fuel), BBQ gas or camping gas.
What is LPG made of?
LPG – Liquefied petroleum gas or liquid petroleum gas, also denoted as just propane or butane, are both flammable hydrocarbon gases used as fuel for LPG heating gases, cooking and vehicular fuel.
LPG is made up of carbon and hydrogen atoms forming propane and butane whilst natural gas is made up of lighter methane, the simplest carbon and hydrogen molecule.
LPG is comprised primarily of propane and butane LPG heating gases, whilst the natural gas primary constituent is methane. LPG is made up of a group of flammable hydrocarbon gases that are liquefied through pressurisation and commonly used as fuel. Natural gas is liquefied cryogenically.
LPG is made up of a number of gases under the LPG products label, including propane, butane, isobutane and mixtures of these gases and are also referred to as natural gas liquids – NGL.
LPG is stored in steel vessels ranging from small BBQ gas bottles to larger gas cylinders and tanks.
Where does LPG come from?
LPG comes from drilling oil and gas wells.
It is a fossil fuel that does not occur in isolation.
LPG products are found naturally in combination with other hydrocarbon fuels, typically crude oil and natural gas.
LPG is produced during natural gas processing and oil refining.
It is isolated, liquefied through pressurisation and stored in pressure vessels.
Refining LPG from Oil and Gas
LPG is produced during natural gas processing and petroleum refining. Propane does not occur naturally in isolation.
LPG processing involves separation and collection of the gas from its petroleum base. LPG is isolated from the hydrocarbon mixtures by separation from natural gas or by the refining of crude oil.
Both processes begin by drilling oil wells. The gas/oil mixture is piped out of the well and into a gas trap, which separates the stream into crude oil and “wet” gas, which contains LPG and natural gas.
The heavier crude oil sinks to the bottom of the trap and is then pumped into an oil storage tank for refining. Crude oil undergoes a variety of refining processes, including catalytic cracking, crude distillation, and others.
The “wet” gas, off the top of the gas trap, is processed to separate the gasoline (petrol) from the natural gas and LPG. One of the refined products is LPG.
The natural gas, which is mostly methane, is piped to towns and cities for distribution by gas utility companies. The petrol is shipped to service stations.
The LPG is stored, under pressure, in various sized cylinders and storage tanks. The LPG fuel also enters the distribution network, where it eventually finds its way to end users, including Home LPG and Commercial LPG users all around Australia and the world.
At the point of use it once again becomes a gas.
What is LPG Used For?
LPG (liquefied petroleum gas) is used in your home, including cooking, heating, hot water, autogas, aerosol propellant, air conditioning refrigerant and back-up generator applications. LPG used in your home is typically supplied in 45kg LPG gas bottles.
LPG – Liquefied Petroleum Gas – has hundreds, if not thousands, of LPG uses including hot air balloons
It is used in leisure time activities including caravans, boats, recreational vehicles and camping.
Business and industry use LPG fuel for a multitude of processes including steam boilers, kilns, ovens and LPG forklifts.
LPG products are also employed as a propellant, refrigerant, vehicle fuel and petrochemical feedstock.
Crop and produce drying, heating greenhouses, hot water for dairies, irrigation pumps and heating animal enclosures are just some of the agricultural applications for LPG.
LPG fuel for transport is also a big user of LPG (Autogas). LPG products can be either as propane or propane mixed with butane, to fuel various vehicle types.
There are also many, many more LPG applications, including power generation and the hospitality industry.
Vaporisation
Did you know that every time you turn on one of your gas appliances, the LPG in your gas bottles starts to boil?
If you could see though the steel, you would also notice that it looks just like water boiling.
The big difference is that it happens at -42°C or -44°F.
Liquid LPG changing to gas vapour is called vaporisation.
To boil, the liquid LPG draws heat from the steel walls of the gas bottle which, in turn, get heat from the ambient air.
LPG liquid boils and turns back into gas vapour when you release some of the pressure in the gas bottle by turning on your gas appliance.
As with water, the more heat that is applied, the more rapidly it boils, vaporising at a faster rate. The vapour pressure in the bottle also increases with temperature.
Given that the steel of the bottle draws heat from the ambient air heat, cold weather will slow down the rate of vaporisation.
Vaporisation also makes the gas bottle feel colder than the ambient temperature. The gas bottle gets even colder when you are actually using the gas.
The LPG gas vapour is held in the top of the bottle and the liquid LPG at the bottom, as shown in the image above.
Almost all of the uses for LPG involve the use of the gas vapour, not the liquefied gas
Chemical formula
There are a number of LPG gas chemical formulas (formulae).
Starting with the lowest carbon LPG chemical formula, the Ethane chemical formula is C2H6.
Propane chemical formula is C3H8.
Butane and Isobutane both have the same chemical formula, C4H10, as isobutane is an isomer of butane.
Pentane (n-pentane) chemical formula is C5H12, but is only a gas over 36.1°C. Heavier hydrocarbons (pentanes plus) are liquids or waxy solids.
Eco-friendly clean burning
LPG heating gas is an eco-friendly choice, as it is a low carbon, low Sulphur fuel.
LPG use results in lower CO2 emissions than other energy sources, such as coal fired electricity. For example, with coal fired electricity, replacing your electric hot water system with a 6-Star LPG continuous flow hot water system may reduce the greenhouse gas emissions produced from your hot water use by about 75%.
It also can help lower greenhouse emissions during the transition to renewable energy sources.
Make the switch to ELGAS
If you are looking for an Australian alternative to electricity, ELGAS could be the perfect energy source for you. Contact ELGAS for home and or business. Our experts are on hand to answer any questions you have and will help you sort out the most cost-effective and energy-efficient solution for your home or business.