Bitumen Blending
Mixing Gilsonite in Bitumen Blending
A new application for Gilsonite has risen within the past 10 years, and that is using natural bitumen as a raw material to make petroleum bitumen. Basically, petroleum bitumen is made from sludge or slurry, obtained from the bottom of distillation tank, at the oil refinery. The slurry is transferred to bitumen manufacturing facilities to get processed into Petroleum Bitumen, also called Penetration Bitumen.
In order to utilize Gilsonite in this application, the material must be mixed with the slurry into the hot blend to make the Bitumen. The most proper material here is Gilsonite Powder 200 Mesh. The Gilsonite powder will react with slurry molecules and gradually form the bitumen particles. This reaction is catalyzed by the heating processes inside production tanks.
This technology is mastered by the Chinese and also is being used in other countries including India & Iran. In such places the road paving standards allow the bitumen manufacturers to supply Gilsonite Blended Bitumen to the road contractors.
This Gilsonite usage results in supplying a lower price product to end users. Many producers apply Gilsonite where the Natural Bitumen is to be reached at a better price than the slurry from the refinery. This allows mixing Gilsonite with slurry at a 20-80 ratio, decreasing the production cost by 5-10% on the final product. In order to do so, the Gilsonite suppliers are securing only high ash content Gilsonite from inexpensive origins such as Iran Gilsonite and Angola Natural Bitumen, rather than costly high-quality Gilsonite from the USA.
Interesting Fact:
When applying Gilsonite into the slurry, the Gilsonite ash content cannot resolve in the oil matter. This is because the cheap natural bitumen’s “solubility in TCE” does not exceed 70-80%. Therefore the resulting product will bear the ash content of the Gilsonite, and its bitumen content will decline to below 99.5%(the petroleum bitumen standard threshold). As a result, the final product will certainly not cover the international standards of road paving if only the economical method of bitumen blending with Gilsonite is used.
Gilsonite in Bitumen Blending – Method Addition
First, gilsonite should be added during the dry cycle of the mixing procedure, onto the hot aggregate rocks, before the bitumen is added. It is generally recommended to extend the total cycle time by about 15 seconds to ensure proper dissolution. 5 additional seconds of dry mixing and 10 additional seconds of wet mixing maximized the Marshal Stability of the paving mix.
Gilsonite can be stored in an additional silo at the pug mill and sprayed into the mixer. gilsonite would be handled in this same manner. A screw feeder or vane feeder that measures out the amount of gilsonite per batch can be calibrated to measure the dosage level of gilsonite per batch.
When gilsonite is introduced at the plant site a gilsonite storage tank is required with a totalizing flow meter, which is not capable of being reset, mounted in the gilsonite feed line just prior to introduction into the mixer.
GILSONITE IN BITUMEN BLENDING – BENEFITS OF NATURAL BITUMEN IN HOT MIX PAVEMENT
- It can be used as a binder modifier to improve strength and performance of road surfaces (pavements)
- Natural bitumen modifier can be used for hot mix pavement and NO additional equipment is required.
- Natural bitumen can be added to recycled asphalt or pavements
- Natural bitumen has been known for its high life, stability, durability, exceptional deformation result, the High-temperature stability of asphalt pavement and it also increase water-stripping resistance.
- Low temperature cracking resistance and water damage.
- Natural bitumen will increase the road strength while road can be almost 20% thinner in comparison to deferent pavements.
GILSONITE IN BITUMEN BLENDING – BENEFITS OF NATURAL BITUMEN IN PAVEMENT SEALERS:
- SEALERS APEARENCE AND DURABILITY sealer look better, last longer and dry quicker
- ANTIOXIDANT, WEATHING PROPERTIES AND BONDING It will invigorate the sealed pavement, Sealer stays black longer and it helps weatherproof the sealer.
