Latest Products Latest Products Tue, 03 Aug 2021 04:56:12 +0530 en-us Bitumen Emulsion Thu, 06 Jun 2019 00:00:00 +0530 Whatever the end use, application conditions usually require bitumen to behave as a mobile liquid. In principle, there are three ways to make highly-viscous bitumen into a low-viscosity liquid : Heat it. Dissolve it in solvents. Emulsify it. Bitumen emulsions are two-phased systems consisting of bitumen, water, and one or more additives to assist in formation and stabilization and to modify the properties of the emulsion. The bitumen is dispersed throughout the water phase in the form of discrete globules, typically 0.1 to 50 microns in diameter, which are held in suspension by electrostatic charges stabilized by an emulsifier. Bitumen emulsions can be divided into four classes. The first two are, by far, the most widely used : ​ Cationic emulsions, Anionic emulsions, Non-ionic emulsions. ​ Clay-stabilized emulsions The terms anionic and cationic stem from the electrical charges on the bitumen globules. This identification system originates from one of the fundamental laws of electricity - like charges repel, unlike charges attract. If an electrical potential is applied between two electrodes immersed in an emulsion containing negatively charged particles of bitumen, they will migrate to the anode. ​ In that case, the emulsion is described as "anionic". Conversely, in a system containing positively charged particles bitumen, they will move to the cathode and the emulsion is described as "cationic". The bitumen particles in a non-ionic emulsion are neutral and, therefore, will not migrate to either pole. These types of emulsion are rarely used on highways. ​ Bitumen emulsions are divided into three categories in terms of setting : ​ Rapid-setting (RS), Medium-setting (MS), Slow-setting (SS) ​ Cationic RS emulsion is currently the widely used category. Emulsion setting is irreversible phenomenon which may occur due to the evaporation of the water phase or the attraction of water by stone materials. Throughout this phenomenon, the water phase disappears and bitumen particles will have less space. Then, the bitumen gradually moves towards the surface or coats the aggregate. Cutback Bitumen Thu, 06 Jun 2019 00:00:00 +0530 Bitumen is "cutback" by adding controlled amounts of petroleum distillates, such as kerosene. Type and quality of Cutback depends on type and amount of solvent in the pure bitumen. The more solvent in Cutback bitumen, leads to the more viscosity in bitumen. Cutback bitumen is used when there is limited access to heating equipment, bitumen decomposition in high temperature, bitumen cooling throughout working, workers safety, fire and time consuming. This type of bitumen is used in road operations for surfacing and pavement. Medium-Curing (MC) bitumen is achieved from solving pure bitumen into kerosene. In Britain and most European countries, new standards about bitumen cutbacks have not been renewed while this country is a leading producer and consumer of cutbacks. The reason for non-renewal of standards for cutbacks in England is environmental concerns and growing oil prices which have raised the price of kerosene and gasoline. Meantime, a new generation of environment-friendly emulsions is emerging. In Iran, bitumen emulsions have not yet become common, but MC250 is widely produced. Cutback bitumen is classified based on viscosity grade. It is divided into three categories :