AsphaltPro published an article titled “Avoid Explosions and Oxidation When Preheating RAP” in the August 2025 issue to discuss the importance of preheating Reclaimed Asphalt Pavement (RAP) before mixing to enhance safety, efficiency, and mix quality. Preheating ensures that RAP reaches the correct temperature before entering the mixing zone, reducing the risk of accidents and improving energy efficiency. 

 

Krishna Srinivasan, President, Sripath Technologies, was interviewed regarding best practices for preheating RAP. He emphasized the significance of preheating RAP, especially when using high-RAP mixes containing 30-50% RAP. Cold RAP can act as a heat sink, lowering the mix temperature to unacceptable levels and leading to poor quality mix production and higher heating costs. Preheating helps drive off moisture, which can also act as a heat sink and increase energy costs if introduced into the mix chamber. Most contractors reduce the amount of RAP in their mixes or reduce throughput tonnage on rainy or damp days to maintain appropriate production throughput and good quality mix. 

 

The article also highlights the importance of matching the temperature of RAP and virgin materials for safety reasons. Cold RAP entering the drum can lead to inconsistent heating, creating hot spots and increasing the risk of burns or fires. Proper steam removal during the RAP preheating process is crucial for both safety and operational efficiency. Preheating RAP is essential for maintaining safety, improving energy efficiency, and ensuring consistent mix quality in asphalt production. 

 

Dosing RAP with ReLIXER®, an asphalt rejuvenator / recycling agent, can further enhance mix performance and sustainability. By rejuvenating aged binders within RAP, ReLIXER restores flexibility and workability, allowing higher RAP content without compromising quality. This combination reduces the need for virgin materials, lowers energy consumption, and supports durable, environmentally responsible asphalt production. 

 

For a deeper dive into strategies, techniques, and expert insights, read the full article on AsphaltPro.Â