What is Propane Gas?
Propane gas, also called LPG, is available almost everywhere.
We use it to heat our homes & hot water, cooking our food, power our BBQs and fuel our cars.
Propane is also used by business and agricultural for all sorts of applications.
It is an amazing transportable gas that comes in a bottle, but what exactly is propane, where does it come from and how does it work?
Propane gas is one of the gases that fits the definition of LPG - Liquefied Petroleum Gas. Propane is a flammable hydrocarbon gas that is liquefied through pressurisation and commonly used as fuel in heating, cooking, hot water and vehicles.
Propane can also be used for refrigerants, aerosol propellants and petrochemical feedstock.
Propane gas can be compressed into liquid at relatively low pressures. Propane is generally stored, as a liquid, in steel vessels ranging from small BBQ gas bottles to larger gas cylinders and LPG storage tanks.
Propane comes from natural gas processing and petroleum refining.
There are a number of other gases that fall under the “LPG” label, including butane (n-butane) and isobutane (i-butane), as well as mixtures of these gases.
Propane Physical Properties
|Energy Content: MJ/m3||95.8|
|Energy Content: MJ/kg||49.58|
|Energy Content: MJ/L||25.3|
|Boiling Temp: Cº||-42|
|Pressure @ 21ºC: kPa||858.7|
|Flame Temp: Cº||1967|
|Gas Volume: m3/kg||0.540|
|Relative Density: H2O||0.51|
|Relative Density: air||1.53|
|kg per L||0.51|
|L per kg||1.96|
|Specific Gravity @ 25ºC||1.55|
|Density @ 15ºC: kg/m3||1.899|
Where Does Propane Come From?
Propane is a fossil fuel that does not occur in isolation.
Propane is found naturally in combination with other hydrocarbons.
It is produced during natural gas processing and oil refining. It is isolated, liquefied through pressurisation and stored in pressure vessels.
How is Propane Made?
Propane is made during natural gas processing and oil refining. It is separated from the unprocessed natural gas using refrigeration.
Propane is extracted from heated crude oil using a distillation tower.
It is then pressurisation and stored as a liquid in cylinders and tanks.
How is Propane Made from Natural Gas?
Propane isn't so much made from natural gas as it is separated from natural gas.
It is important to understand that "raw natural gas", as it leaves the gas well, contains other gases (including propane) and impurities that need to be processed out to obtain the nearly pure methane gas that we refer to as "refined natural gas" or just "natural gas".
Propane is separated from the raw natural gas stream by 'stripper plants' that literally strip the propane from the raw natural gas stream.
What is Propane Used For? The condensed version:
Propane is utilised in numerous applications.
Propane is used as a fuel for many residential, commercial and agricultural heat applications, including cooking.
It is also employed as a propellant, refrigerant, vehicle fuel and petrochemical feedstock.
7 Important Propane Facts
1. Propane is LPG but not all LPG is propane. LPG is the acronym for Liquefied Petroleum Gas.
2. Propane is a flammable hydrocarbon gas that is liquefied through pressurisation and commonly used as fuel.
3. Propane comes from natural gas processing and petroleum refining.
4. Propane is LPG but not all LPG is propane. Propane, along with a number of gases, falls under the “LPG” label. The other gases include butane (n-butane) and isobutane (i-butane), as well as mixtures of the three LPG gases.
5. Propane gas can be compressed into liquid at relatively low pressure.
6. Propane is frequently used for fuel in heating, cooking, hot water and vehicles.
7. Propane is generally stored, as a liquid, in steel vessels ranging from small BBQ gas bottles to larger gas cylinders and storage tanks. (45kg gas bottles shown)
Propane Goes by Many Names
In Australia, propane has many names.
It is also called LPG, LPG Gas, LP Gas, BBQ Gas or Autogas.
In the USA it is just called Propane.
In the UK, it is referred to as either propane or LPG.
How Does Propane Work?
Propane is stored under pressure, as a liquid, in a gas bottle.
It turns back into gas vapour when you release some of the pressure in the gas bottle by turning on your appliance.
Almost all of the uses for propane involve the use of the gas vapour, not the liquefied gas.
What is Propane Made of? Propane Composition
Propane is a hydrocarbon gas with 3 carbon and 8 hydrogen atoms in a propane molecule.
The chemical formula for propane is C3H8. (Propane molecule model shown)
Propane is not made or manufactured, it is found naturally in combination with other hydrocarbons.
Propane is produced during natural gas processing and petroleum refining.
Both processes begin by drilling oil wells.
Propane does not occur naturally in isolation.
Propane processing involves the separation and collection of the gas from its petroleum base and other Natural Gas Liquids (NGLs).
Following its refinement, LPG is stored and distributed as a liquid under pressure until used, at which point it is utilised as either a liquid or a gas (vapour).
What is Propane Used For?
Propane has hundreds, if not thousands, of uses.
The propane uses most people can name are around the home, in their cars or for their business.
It is used in leisure time activities including caravans, boats, recreational vehicles, hot air balloons and camping.
Business and industry use propane for a multitude of processes including steam boilers, kilns, ovens and forklifts.
Crop and produce drying, heating greenhouses, hot water for dairies, irrigation pumps and heating animal enclosures are just some of the agricultural applications for propane.
Transport is also a big user of propane, either alone or mixed with butane, to power various vehicle types.
There are also many, many more propane applications, including power generation and the hospitality industry.
What are the Properties of Propane?
Propane Boiling Point
Water boils at 100°C, becoming a gas (steam).
In contrast, propane boils at -42°C becoming gas vapour.
Propane stays liquid because it is under pressure in a gas cylinder.
As a liquid, it looks a lot like water.
It is colourless and odourless in its natural state.
Odourant is Added for Safety
Avoid Direct Contact - Cold Burns
Specific Gravity of Propane - Density
Propane Gaseous Expansion
Energy Content of Propane
Propane Flame Temperature
Limits of Flammability
Propane Flash Point
Propane Vapour (Gas) Use vs. Liquid Use
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The information in this article is derived from various sources and is believed to be correct at the time of publication. However, the information may not be error free and may not be applicable in all circumstances.