Recycled Asphalt Pavement (RAP)
Systems to introduce reclaimed asphalt into the hot asphalt mix
With increased costs of energy and the reduced availability and cost associated with extracting and processing virgin materials, the addition of recycled asphalt pavement (RAP) into the hot asphalt mix is becoming an increasingly important factor in surfacing materials and consideration by us for asphalt specifiers and producers alike.
Parker have for many years been designing solutions and overcoming the difficulties associated with the introduction of RAP materials to achieve more economical and environmentally acceptable methods of asphalt production.
RAP bins and RAP system on StarBatch asphalt plant, showing conveyor/elevator feeding reclaimed material directly into the mixer.
Systems are available to allow introduction of the pre-processed cold RAP material directly into the asphalt plant hot elevator at a ratio of approximately 10%, or a higher percentage of approximately 25% can be achieved with a direct feed into the mixer process. Equipment to monitor and control the amount of RAP material introduced either by volume or by weight would be included within the system along with moisture evacuation equipment integrated into the operational process and control system of the plant.
RAP addition systems can be designed from our experience and standard range of equipment for inclusion within new plants or for retro-fitting into existing asphalt plants and will include some or all of the following:
- Suitable free flowing cold RAP feed hoppers including variable speed feeder systems.
- Feed system belt conveyors and elevators for RAP transfer.
- Volumetric and weight metering equipment.
- Self-sealing feed chute systems for introduction of RAP materials into mixer and/or elevator.
- Integration of RAP control system into batch control operation.
- Steam evacuation systems and associated ducting.
Other equipment and systems can be designed to suit specific requirements and higher levels of RAP material introduction.