Petroleum Asphalt Plant: Q - Iso Technology Co., Ltd. Seoul, Korea
Petroleum Asphalt Plant: Q - Iso Technology Co., Ltd. Seoul, Korea
Petroleum Asphalt Plant: Q - Iso Technology Co., Ltd. Seoul, Korea
OPTIMUM
SOLUTION
PROJECT
MANAGEMENT
FRONT-END
ENGINEERING
TOTAL SOLUTION
Since 2000, Q_iso Technology Co., Ltd. (Q_iso) has primarily involved in front-
end engineering, process and mechanical design in the field of oil & gas,
petrochemical and power industry.
AIR BLOWING
* Blown Asphalt
OXIDATION
Straight
Straight * Cut-Back Asphalt
Asphalt BLENDING
* Primer
CATIONIC * Emulsified Asphalt
EMULSIFICATION
PETROLEUM ASPHALT
Asphalt is a dark brown to black, highly viscous, hydrocarbon produced from petroleum distillation
residue. It is further processed to impart characteristics required by its final use.
Asphalt cement, a kind of binder, is used prominently in the paving industry: Some asphalt
cements require modification in order to meet specifications. The benefits of modified asphalt
cement can only be realized by a judicious selection of the modifier(s); In general, asphalt
cement should be modified according to the types of improvements.
■ EMULSIFIED ASPHALT
Emulsified asphalt is a suspension of small asphalt cement globules in water, which is assisted
by an emulsifying agent (such as Soap). Emulsions have lower viscosities than neat (plain)
asphalt and can thus be used in low temperature applications. After an emulsion is applied, the
water evaporates away and only the asphalt cement is left. Emulsions are often used as prime
coats and tack coats.
■ CUTBACK ASPHALT
Cutback asphalt is a combination of asphalt cement and petroleum solvent. Like emulsions,
cutbacks are used because their viscosity is lower than that of neat asphalt and can thus be used
in low temperature applications. After cutback is applied the solvent evaporates away and only
the asphalt cement is left.
■ FOAMED ASPHALT
Foamed asphalt is formed by combining hot asphalt binder with small amounts of cold water.
When the cold water comes in contact with the hot asphalt binder it turns to steam, which
becomes trapped in tiny asphalt binder bubbles.
Reside from vacuum distillation unit or from solvent deasphalting (Vacuum Distilled Bitumen or
Straight-run Asphalt) is upgraded by oxidation with air. Figure 1 provides a simplified process flow
diagram.
A batch of the feedstock is preheated in the preheater up to 190°C ~ 220°C by circulating oil like Dow-
them through heating coils within the heater and then the preheated asphalt flux is introduced into the
oxidizer by the feed pump.
Air is blown through the asphalt flux that is heated to about 230°C ~ 250°C, starting polymerization
and exothermic reaction. During the reaction, the certain amount of heat is released and then
temperature of the reacted becomes higher than the required operating 230°C.
The temperature is controlled by regulating an amount of air and by circulating oil or water through
cooling coil within the oxidizer. The oxygen in the air reacts with hydrogen in the feedstock to form
water, and the reaction also couples smaller molecules of asphalt into large molecules to create
heavier product. These reactions change the characteristics of the asphalt to produce with the desired
products-blown asphalts.
On the other side, the off-gases from the process are scrubbed in a wet scrubber where alkaline
water is circulated so as to remove hydrocarbons prior to the further purification treatment system.
In the further process, cut-back asphalt and asphalt primer, modified asphalts, are prepared by
blending solvent and some additives with the blown asphalts in the blending tanks.
Before entering the emulsification process, the base asphalt is prepared in a feed preparation tank
where the feeds, vacuum reside oil with some portion of cut-oil are circulated and homogenized by a
jet-mixer.
On the other hand, soap solution is prepared in a chemical solution preparation tank where the water
is mixed with emulsifying agents and some additives and heated by steam until its temperature rises
up to the required level.
In the process, the main feature is, the molten asphalt is sheared to fine droplets by a colloid mill
system figured in the above, which does its work by hydraulic shear, bringing to bear a tremendous
amount of energy on a small portion of material in the form of a thin film. Within the colloid mill the
asphalt is brought into intimate contact with a chemical solution. This is the chemical stabilization.
As the temperature of the emulsified asphalt discharged from the colloid mill is ranging approx. 90°C,
it is cooled down to 40°C ~ 60°C by a cooler so as to prevent water vaporization.
The emulsified asphalt is finally stored in storage tanks covered with insulation where the temperature
maintains 40°C ~ 60°C to keep the stabilization of the emulsion.
Straight-run asphalt is used as feedstock to produce blown oxidized asphalt or paving roads, airport
runways, and parking lots.
Because of its solid to semi-solid nature, it must first be "cut" with a solvent to bring it to a more liquid
state.
Note: The above is a typical specification of the feedstock, which have been
used as main raw materials.
The figure shows a typical asphalt batch plant, which can be provided in combination with the
asphalt plant or in separation from by Q_iso, meeting the client's requirement.
Note : The equivalent products are available in the products range of Dong Nam Petrochemical
Co., Korea.
Asphalt Cement:
Asphalt that is refined to meet specifications for paving and special purposes (ASTM D946). Asphalt
cements are graded by penetration or viscosity. Its penetration is usually 40~300 and its viscosity is
150~4000 poise.
Cutback Asphalt:
Asphalt cement, which has been liquefied by blending with petroleum solvents, as for the RC and MC
cutbacks.
Emulsified Asphalt:
An emulsion of asphalt cement and water that contains emulsifying agent, a heterogeneous system
containing two normally immiscible phases in which the water forms the continuous phase of the
emulsion, and minute globules of asphalt form the discontinuous phase. Emulsified asphalt are
usually classified by rate of set-RS (Rapid Set); MS (Medium Set); and SS (Slow Set)
Asphalt Primer:
A low viscosity asphalt product that penetrates into a no bituminous surface upon application.