High quality bitumen (80%) and finely ground tire rubber (GTR) (20%) are thermally reacted and pelleted with 1% hydrated lime. The “wet process” reaction of the asphalt bitumen and rubber yields the best performance characteristics of asphalt rubber binders, and the lime provides excellent bonding of the binder and aggregate, acting as an anti-strip agent to prevent moisture damage on the pavement. Hydrated Lime anti-strip is so effective that it is mandated for use in HMA pavements by 28 US states.

The benefits of wet process asphalt rubber have been well documented. When compared to neat asphalt, the asphalt rubber gives lower life cycle costs, more durability and quieter pavements lowering noise pollution. More information can be found at http:/rubberpavements.org/library.html.

During hot mix production, the GTR pellets are metered into the mixing chamber via a RAP feeder or directly into the pugmill, just as is done with conventional asphalt. Melting of the pellets occurs in 30 to 40 seconds.

We can also give the pelleted bitumen a 2-5% warm mix asphalt polymer shell, so the pellets can be used in warm mix asphalt (WMA).

To obtain higher production levels at the hot plant and still meet asphalt-rubber specs, GTR concentrate pellets with 4 or 5% polymer shell are used. The contractor can add 1 to 2% of local liquid bitumen to the heated aggregate in the mixing chamber before adding the GTR Paving Pellets to accelerate pellet melting and achieve the preferred ratio of rubber to bitumen. Our 70/30 blend will allow for minimum 20% rubber content and a 3% warm mix polymer ratio in the finished product.

Enables large and small recycled tire pavement projects
Enables shipping of GTR asphalt binder with no heat, separation, or sticking
Simplifies and speeds HMA manufacture using asphalt rubber and lime
Recycles up to 2,000 waste tires per mile
Saves energy

No need for insulated trucks, steam rail cars or ships to haul bitumen
No heated bitumen tanks or mixers required during storage.

No additional equipment needed at hot or warm mix plant site
No separation of asphalt rubber binder nor plugging of bitumen lines and pumps
No need for agitated asphalt rubber storage tanks
No fumes or odors emitted during storage and transport
No need for adding an anti-strip (with Paving Pellets, it is in there!)
Pellets can be used in any type of large or small, fixed or portable HMA or WMA mixing configuration
Any hot mix plant can easily manufacture asphalt rubber mix

The graphic shows the increased efficiency of our process in producing ground tire rubber (GTR) hot mix asphalt (HMA).