Propane-butane technical mixture is a fuel for municipal and industrial use. It belongs to the category of hydrocarbon gases, which liquefy when pressure increases. They are produced on the base of associated petroleum gases and the extracted from gas condensate deposits.
Propane-butane technical mixture is the result of combination of two gaseous hydrocarbons: propane and butane in proportions depending on the purpose and conditions of use of the gas. For a cold climate, a mixture of propane and butane with more propane content can be used, because butane freezes at minus temperatures. And for a warm climate about 60% of butane is added to the mixture, since propane is explosive when heated.
GOST does not set the precise proportions of propane and butane in the mixtures, but only the maximum permissible limits (butane up to 60%). But it uniquely determines other important characteristics:
- Liquid residue at 20 ° C – up to 1.6%.
- The presence of hydrogen sulphide (including mercaptan sulfur compounds) – up to 0.013%.
- The intensity of the odor is from 3 points according to GOST 22387.
- Absence of water and alkalis in total mass.
- The saturated vapour pressure at +45° C is from 1.6 MPa.
- Density depends on the mixture composition and air temperature, the average value at 20 ° C is from 0.500 to 0.573 t / m3. As the temperature rises, the density decreases.
Propane-butane gas mixture is 2.5 times heavier than air and can accumulate in basements and wells, which is unsafe. Therefore, the installation of gas equipment on the ground floor is prohibited.
Application of propane-butane technical mixture
In Russia Propane-butane mixture is used for the following purposes:
- Raw materials in the oil refining and chemical industries (in particular, the production of automobile tires).
- Household use for gas stoves, central and autonomous gas supply.
- Automotive fuel (more often it is propane-butane for cars, but propane-butane technical mixture is also used in some cases).
- Export deliveries.
Hydrocarbon liquefied gas called the propane-butane technical mixture is inflammable and explosive liquid that is transported in bombs and tanks. Initially, this mixture has no odor, so it is given a specific smell with ethyl mercaptan (hence the unpleasant smell of sulfur) for a quick detection and elimination of leaks.