Bitumen is a binding material, technically a hydro carbon, which is present in asphalt. It is also sometimes called mineral tar or simply asphalt. It is obtained by partial distillation of crude petroleum. In North America, bitumen is commonly known as “asphalt cement” or “asphalt”. It is a sticky, black and highly viscous liquid or semi-solid form of petroleum. The terms asphalt and bitumen are often used interchangeably to mean both natural and manufactured forms of the substance. In American English, asphalt (or asphalt cement) is the carefully refined residue from the distillation process of selected crude oils. Outside the United States, the product is often called bitumen. Geological terminology often prefers the term bitumen.
1. Bitumen emulsion : It is a liquid product containing bitumen to a great extent in an aqueous medium. Bitumen is in a very finely divided state and it is suspended in the aqueous medium with the help of some suitable stabilizing agents. Bitumen emulsions have a low viscosity compared to the bitumen from which they are produced and can be workable at ambient temperatures. Class 4. Bitumen emulsions can be divided into four classes: The first two are most widely used : 1) Cationic emulsions.
If an electric potential is supplied between two electrodes immersed in an emulsion containing positively charged particles of bitumen, they will migrate to the cathode. This emulsion is said to be cationic.
2) Anionic emulsions.
If an electric potential is supplied between two electrodes immersed in an emulsion containing negatively charged particles of bitumen, they will migrate to the anode. This emulsion is said to be anionic.
3) Non-ionic emulsions.
If the bitumen particles in the emulsion are neutral, then they will not migrate to any of the pole.
These type of emulsions are NON-IONIC.
Mainly used in road ways.
4) Clay-stabilized emulsions.
These are mainly used for industrial...
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