The additives used in the process are lime, cement, slag, fly ash, and various blends of these materials. The pavement surface is heated by infrared radiation and milled in two steps to a desired depth, 20-65 mm. The mix of the old asphalt layer can be changed directly by adding virgin asphalt and new type of bitumen or rejuvenator. The two-stage recycling means the sequential heating and removing of two separate layers of asphalt in one continuous operation. Materials savings are realized from the reduction in new asphalt and aggregate.
Energy savings result primarily from reduced aggregate haul and drying, and asphalt transportation.
Cost savings are greatly influenced by length of aggregate haul and distance from the plant to the job site. Other factors which have a major influence on bid prices are the degree to which contractors in the area are familiar with and equipped for recycling, the size of the State's present and projected recycling program, and State contract procedures . The equipment required to implement this system is available through several vendors like Pyrotech Asphalt Mfg. The equipment required to perform recycling operations of asphalt is very costly. This technology hasn't had a great impact yet because of a greater emphasis on concrete pavements over asphalt pavements.