Oxidized bitumen is mainly used for industrial purposes, such as roof insulation, flooring, industrial mastics, pipe coating, and paints. Oxidized bitumen is categorized based on softening points and penetration rate. For example, oxidized bitumen 85/40 is a type of bitumen whose softening point is 85±5 degrees Centigrade and its penetration rate is 40±5 mm.
Under the heat, oxidized bitumen is also expected to compensate for weight loss. Compared to regular bitumen, oxidized bitumen has a much higher softening point, reducing its thermal sensitivity. Compared to roads made from bitumen, oxidized bitumen has a higher penetration index (PI) (8>PI>2) because the oxidized bitumen has a gel-like structure.
By passing air through the penetration grades, blown bitumen grades of oxidized bitumen are produced. Bitumen that has been heated in this way is rubbery and harder than the original formula. Under controlled temperature conditions, hard bitumen is widely used in the piling industry as a slip-resistant layer compound, roofing felts, and waterproofing in the roofing and waterproofing industries, undercarriage sealants, electric cable joints, joint fillers and sealants, and in many other applications. Used to seal saw cuts, joints, and other surfaces where minimal movement is expected. Furthermore, bituminous marine mastic is used for the construction of oil and gas pipeline joints.
These are the grades that have the highest popularity: 95/25, 85/25, 90/40, and 115/15. Blown Bitumen can also be produced by our company in other grades upon request by our customers. They are ideal sealants for preventing bleeding at high temperatures due to their high softening temperatures. For blown grade bitumen, broken up pieces should be heated slowly to application temperature of 220oC to 230oC (molded into cake form). Automobile undercarriage sealants are mainly made of oxidized bitumen with anti-slip properties in the piling industry. Apart from being used to make roofing felts and sound dampening felts, it is also used as a sealant compound and as joint filler. Furthermore, bituminous marine mastic is constructed using oxidized bitumen, which is needed for pipeline joints. The Bitumen can be obtained in different grades, such as 95/25, 85/25, 75/25, 90/40, and 115/15. Other grades of Oxidized Bitumen can also be manufactured by RABIT (RAHA BITUMEN) Co. depending on individual customer needs.
Oxidized Bitumen has the major advantages of being completely waterproof, highly flexible, and durable. In addition, it is very stable chemically. Aside from being completely water-resistant, oxidized bitumen is also electrically stable, flexible, and chemically stable. Finally, Oxidized Bitumen has a number of very notable technical advantages that have made it a very popular compound in many different applications. To know more about oxidized bitumen, contact top bitumen suppliers in the UAE.
Advantages
Water resistance, flexibility, and durability are some of the main advantages of Oxidized Bitumen. The chemical stability of the material is further improved. Aside from being completely water-resistant, oxidized bitumen is also electrically stable, flexible, and chemically stable. Oxidized Bitumen has some very distinguished technical advantages, which are why various industries seek its use.
- Durability
- Flexibility
- Water Resistant
- Chemical Stability
Compared to paving grade bitumen:
- Reduced temperature susceptibility
- Exhibits a more ‘solid’ nature at ambient temperatures
- High penetration index
Application
- Oxidized Bitumen has a wide variety of industrial applications.
- As a bonding bitumen for roofing sheet membranes.
- As a hot-applied waterproofing layer.
- Carpet tile manufacture.
- As a raw material for liquid bitumen coatings
- For production of bituminous pains, mastic
- For rustproof pipe coatings
- Used as an anti-slip layer compound in the piling industry
- Used for production of roofing and sound dampening felts, Used as undercarriage sealant in the automobile industry, electric cable joint protection, joint filling compound, sealant compound, and many more in our day-to-day life.
How to produce Oxidized Bitumen (Blown Asphalt)?
The properties of BITUMEN can be modified by air blowing in batch processes.
Vacuum bottom (VB) in liquid form is created by blending & blowing bitumen with a distillate fraction of petroleum and is usually done in tanks equipped with coils for agitation or with a mechanical mixer or vortex mixer. A blowing production tower introduces heated air at a temperature of 150 to 250 °C. BITUMEN is then transported via the blowing production tower to the top of the tower. As a result of the chemical reactions, bitumen has a different mixture of molecular structures. There are catalysts that can influence this process.
In order to produce OXIDIZED BITUMEN, several steps are required. These include filling tanks, blowing BITUMEN into condensers, and packaging the product. So, in the beginning, the loose BITUMEN shipped to the plant by tanker is transferred to the raw material store tanker.
It is designed at the bottom of the store tanker to heat the BITUMEN so that it can be transferred easily to the blowing tower. BITUMEN can be loaded directly into the blowing towers if they are empty, and blowing operation can commence as soon as we upload it.
A blowing tower is filled to 70% in order to deal with the increased volume of BITUMEN resulting from blowing and the possibility of it overflowing.
The material is usually injected with air when its temperature gets to 190-230 degrees.
At the top of the tower are pipes that are filled with air and at the bottom, BITUMEN is dispersed monotonously in phase via a nozzle, oxidation is carried out accordingly and light molecules, volatile gases, and steam are emitted from the top of the tower.
An ideal temperature range for blowing is 265 to 270 °C, though 215-290 °C is also acceptable. Burner constructed at the base of the tower provides the needed heat. Due to the calorific nature of the BITUMEN reaction, water injection, burn extinguishers, and reduction of air amounts can be used to prevent explosion risks caused by temperature increases.
Testing BITUMEN properties and samples from towers are usually required to identify blowing endpoints. BITUMEN OXIDIZED TO SPECIFIC PROPERTIES is no longer blown. This time, BITUMEN was heated up to fix the final stage and depolymerize. Putting the items into storage and presenting them for sale is necessary after they have been packed.
As a result, BLOWN BITUMEN (OXYDE BITUMEN) has significantly more molecular interactions than its original formulation, making it more cohesive. A blow causes the softening point to increase and the penetration to decrease. Usually, though, softening point increases more than penetration decreases. This means that blowing reduces bitumen's temperature sensitivity. Blowing is highly dependent on the original bitumen (i.e., the original mixture of molecular structures).
During the manufacture of the blowing tower, a pipe was fixed on top that carried the produced steam and gas to the condenser. It is here that the bad-smelling gases and oily and volatile parts are separated and transferred to sewage along with water. Additionally, uncombined gas parts are vented from the top of the condenser and then transferred to the furnace and burned. The blowing oven is completely loaded and packed after it is cooled to 150-160°C and all the contents of the blowing oven have reached this temperature. OXIDIZED BITUMEN is transferred to the ground using specific gravity as a result of the liquid height of the blowing tower.
The products are packaged in carton boxes of 20Kg & 25Kg, polyamide meltable bags of 20Kg & 25Kg, kraft bags of 20Kg, 25Kg & 40Kg, and 20Kg, 25Kg drums. Each section has multiple taps so that blown bitumen (oxidized bitumen) can be applied to a specific pack at the same time (to prevent it from cooling & hardening).
Oxidized bitumen production process by air blowing:
- VACCUM BOTTOM or BITUMEN heating to 230-270 °C
- Transferring VB or Hot Melted BITUMEN to Blowing towers
- Blowing air to VB or BITUMEN
- Cooling AIR BLOWN BITUMEN
- Packing (Carton Box, Polyamide Bag, Kraft Bag, Drum, Block)
The procedures of producing bitumen are as follows:
- Continuous blowing procedure
- Discontinuous blowing procedure (Batch wise)
In addition to these two procedures, there are two others named catalysis and anti-catalysis. In catalysis, some chemical material is added during the process to reduce blowing reaction time.
For the following reasons:
- Ease and simplicity in changing blowing conditions and have products with different grades as a result.
- Ease in generating the unit.
- Ease in technology and low expense in investment.
The discontinuous producing procedure is chosen.
Oxidized Bitumen Specifications
| OXIDIZED BITUMEN GRADES | TEST METHOD | |||||
|---|---|---|---|---|---|---|
| 85/25 | 85/40 | 95/25 | 95/40 | 115/15 | ||
| Relative Density at 25°C, g/ml | 1.00-1.06 | 1.00-1.05 | 1.00-1.05 | 1.00-1.05 | 1.00-1.06 | ASTM D70 |
| Softening Point (Ring and Ball), dec C | 80-90 | 80-90 | 90-100 | 90-100 | 110-120 | ASTM D36 |
| Penetration at 25°C, 0.1 mml | 20-30 | 35-45 | 20-30 | 35-45 | 10-20 | ASTM D5 |
| Flash Point (Cleveland open Cup), °C, Min | 200 | 200 | 200 | 200 | 200 | ASTM D92 |
| Loss on heating % by mass | 0.2 | 0.5 | 0.2 | 0.5 | 0.2 | ASTM D6 |
| Ductility at 25 °C cm, min | 2.0 | 2.0 | 2.0 | 2.0 | 2.0 | ASTM D113 |
| Solubility in toluene % wt min | 99.0 | 99.0 | 99.0 | 99.0 | 99.0 | EN12592:2000 |
