|LPG is the abbreviated word of Liquefied Petroleum
Gas. Petroleum Gas is produced by boiling crude
oil in the distillation column. LPG, Naphtha, Kerosene,
Diesel, Bunker oil, AP are produced from crude oil.
The gaseous materials(Propane and Butane) from crude
oil are called Petroleum Gas. The Petroleum Gas
becomes LPG when it is compressed at high pressure.
|(1) LPG mainly consists of Propane
Propane and Butane are chemical compounds of hydrogen
and carbon. These compounds are called hydrocarbon.
Propane consists of 3 carbons and 8 hydrogens and
Butane consists of 4 carbons and 10 hydrogens. Butane
and Propane differ in properties for Butane has
1 more carbon than Propane
|[Table] Physical and chemical properties of pure
Propane and Butane
|Specific gravity of Gas state
||Air is 1
|Specific gravity of Liquid state
||Water is 1
|Vapor pressure(kg/cm, 20℃)
(Volume % in the air)
|(2) When LPG(Propane) is liquefied,
the volume decreases to 1/250, Therefore, large
quantity can be stored in a vessel.
(3) Sulfur which may become oxides of sulfur exists
little in LPG. And LPG doesn’t contain carbon monoxide(CO).
(4) LPG’s caloric value is very high(Propane:23,000kcal/Nm3,
(5) Large quantity of air is required for perfect
combustion(Propane: 24.24Nm3, Butane:32.23Nm3).
For comparison, refer to that hydrogen and carbon
monoxide needs 2.38Nm3 and methane needs 9.52Nm3
(6) Liquid volume of LPG varies according to the
temperature. Liquid state of LPG is 1.5 times lighter
than water and Gas state of LPG is 1.52 times heavier
(7) Pure LPG is odorless and colorless. However,
an agent for odor is added to help recognition of
(8) LPG exists as a gaseous type in the normal temperature
and pressure. However, it is easy to liquefy LPG
at a relatively low pressure.
|3. Safety and Other Information
|(1) Volume expansion of LPG
It is enacted that LPG should not be filled over
85% of inner volume of the filling vessels on the
basis of the ‘Safety Control and Business Regulation
of Liquefied Petroleum Gas Act’. The volume of liquid
state of LPG gets bigger as the temperature rises.
The volume expansion rate of LPG is 15~20 times
higher than water and 100 times higher than metals.
In the condition that LPG is filled upto 85% in
a vessel, if the temperature reaches at 60℃, liquid
type of LPG fully expands in the vessel. And if
the temperature rises over 60℃, the vessel will
explode. This is why the temperature of LPG vessels
should be kept under 40℃ by law.
(2) Recognition of LPG leakage
Both Propane and Butane originally don’t have any
odor and color. However, an odorant is added to
help the recognition of LPG leakage. The legally
allowed quantity of odorants is as much as it can
be smelled when the concentration of leaked LPG
is 0.1%. Even though LPG starts to smell, it doesn’t
mean that it explodes righ away. The concentration
for LPG’s explosion is over 2%.
(3) How to act when LPG leaks
Gas also has its own weight. Propane is 1.5 times
heavier than the same volume of air and Butane is
2.0 times heavier. So, Propane and Butane sink toward
the bottom when they leak. That is why even we open
the windows, the leaked gases remain on the floor.
To discharge leaked gases outside, use brooms or
floor cushions, etc. It is why LPG usage in the
basement is so dangerous.
(4) Effect of LPG on Human
Pure LPG is nontoxic. However, if it is inhaled
continuously, it may cause sleepiness or light anesthesia.
Skin contacts to LPG may cause frostbite because
the evaporation heat at the boiling point is big(Propane:
101.8Kcal/Kg, Butane: 92.09Kcal/Kg).