Bitumen specification is highly related to the bitumen type whether it’s pure, or not and the refining process.
Generally speaking, some types of bitumen are obtained in nature due to the gradual
conversion of crude oil and the evaporation of its volatiles over years.
This type is called natural bitumen and is more durable than oil bitumen.
It exists in pure form in nature (lake bitumen), such as Behbahan Iran
bitumen lake and American Trinidad bitumen lake, or it is mined (mineral bitumen).
Blown bitumen has different bitumen specification due to its different processes.
They obtain this type by blowing hot air into pure bitumen in the final stage of purification.
In this process, hot air at a temperature of 200 to 300 ° C blows into the bitumen chamber by perforated pipes.
As a result of this process, the hydrogen atoms in the molecules of the bitumen hydrocarbons combine with the oxygen in the air, and by the formation of water, the polymerization takes place.
Blown bitumen has a lower degree of penetration than pure bitumen, has a higher degree of softness, and is less sensitive to temperature changes.
This type of bitumen is highly applicable in making roofing sheets, car batteries, and plating. It is important to know that the abbreviation for blown bitumen is R.
For example, 80/25 R bitumen means blown bitumen with a degree of softness of 80 and a degree of penetration of 25.
Mixed bitumen is a mixture of bitumen and a suitable solvent (eg kerosene or gasoline). This bitumen is liquid at room temperature or liquefies at low temperatures.
Mixed bitumen is applicable in types of paving and macadam asphalts.
The setting or hardening rate of this type of bitumen depends on the type of solution.
For example, due to the high rate of evaporation of gasoline, the bitumen dissolved in gasoline hardens faster.
This bitumen is hardening bitumen (RC). Bitumen that dissolves in oil is also bitumen (MC) and bitumen that dissolve in gas oil or furnace oil are retardant oil (SC).
Soluble bitumen grades are based on their degree of viscosity.
Bitumen specification make it suitable for both road construction and insulation.
About 90% of the bitumen produced has applications in road construction; however, insulation costs account for only 10% of bitumen consumption.
Bitumen specification allows it to insulate roofs and bathroom floors. The substance is appropriate for conjunction with a sack.
Sack fibers act as reinforcing bitumen and stabilize the bitumen in place.
Products such as bitumen cardboard or bitumen felt also have a similar application to bitumen.