NATURAL BITUMEN

NATURAL BITUMEN (GILSONITE)

The History Says

In the ancient middle-east, natural bitumen deposits were used for mortar between the bricks and stones, ship caulk, and waterproofing. In Persian, natural bitumen is known as “mumiya.” Some say that this may be the source for the English word “mummy.”

The Present Scenario

Asphalt is hard to transport. It hardens unless kept very hot. For this reason, it is sometimes mixed with diesel oil or kerosene before shipping. At delivery point, these lighter materials are separated. This mixture is often called as bitumen feedstock, or BFS.

ASPHALT, also known as Natural Bitumen, is the most common variety of bitumen (also called mineral pitch). It is a compact, glassy, brittle, black or brown mineral. It is highly viscous liquid or semi-solid which is present in most crude petroleums and in some of the natural deposits. It breaks with a polished fracture, melts very easily giving a strong pitchy odor when heated, and leaves no ashes when pure asphalt is burnt.

Natural Bitumen is sometimes confused with tar, coal tar, or pitch because the appearance is similar and the substances may be used interchangeably in many industrial processes. Tar and pitch are obtained from the coal products that are chemically and physically different.

Some other names of asphalt are road tar, road binder, petroleum pitch, petroleum asphalt, mineral pitch, and seal-coating material.

Types of Natural Bitumen

There are two main types of Natural Bitumen. They are as follows:

Straight-run natural bitumen or asphalt cement – These are used for paving roads, airport runways, and packing lots. Since its nature is solid to semi-solid, it must first be cut with a solvent in order to bring it to a more liquid state. This process is known as Cut Back Asphalt. Highway workers mostly use straight run asphalt.

Air-blown or oxidized natural bitumen – It has a high softening point and is primarily used in roofing, pipe covering, and in other similar situations.

Uses of Natural Bitumen

Natural Bitumen is used for road paving, roofing tar, roofing felt, roll-roofing, shingles, pipe covering, waterproofing, floor tile, and many other products and processes.