Asphalt Processing with NaRePAK – Recycling of PAH-Containing Road Construction Materials
A process developed by Eisenmann Environmental Technology is being implemented.
Asphalt processing: RiA.H
Raw material recovery through innovative asphalt processing in the Harz region using the NaRePAK process ("Nachhaltiges Recycling von PAK-haltigen Straßenausbaustoffen – Sustainable Recycling of PAH-Containing Road Construction Materials"). Background: In Germany, more than three million tonnes of tar-containing road millings are produced annually, classified as hazardous waste. To date, these road millings are predominantly deposited in landfills or thermally treated in the Netherlands. This new approach to asphalt recycling helps reduce the amount of reclaimed road material that would otherwise be sent to landfills.
Patented Solution
For the treatment of PAH-contaminated road millings, Eisenmann has conducted various tests in a rotary kiln pilot plant since 2009. A gentle process at temperatures of around 600 °C was developed and filed for patent. Thanks to this gentle process, the recovered rock material can be almost completely reused. This process was awarded the Baden-Württemberg Environmental Prize.
The NaRePAK process was further developed together with the Bettels Group from Hildesheim to industrial maturity. The Bettels Group and we are working to implement the process concept with further partners at additional sites.
Details of the plant for the treatment of tar-containing road demolition material
- Capacity of up to 135,000 t/a of tar-containing road demolition material
- Regional focus based on the proximity principle
- Robust, innovative process, proven on an industrial scale
- Patent held by Eisenmann Environmental Technology with an exclusivity agreement with the Bettels Group
- Aggregate-friendly, near-autothermal process at 570–600 °C using the bitumen content as an energy source
- heat recovery and flue gas treatment
- Products usable as aggregate for asphalt (in accordance with FGSV) and concrete
Further information at RIA.H – Homepage
Want expert advice?
Simply contact us by phone or in writing. We will be happy to help you find the optimal solution for your task.
Frequently asked questions about NaRePAK
What is the NaRePAK process?
NaRePAK is a process for the treatment of PAH-contaminated road construction materials. In this process, tar-containing asphalt is treated thermally to remove contaminants and recover valuable mineral raw materials. The treated material can then be reused as aggregate in asphalt or concrete production. The process was developed by Eisenmann Environmental Technology and further advanced to industrial scale together with the Bettels Group.
What is tar containing asphalt?
Tar containing asphalt contains polycyclic aromatic hydrocarbons (PAHs), which are considered harmful to both the environment and human health. As a result, this material is classified as hazardous waste and cannot be reused in the same way as conventional asphalt. To recover and reuse the valuable mineral raw materials it contains, the contaminants must first be removed or treated safely.
Why does tar containing asphalt need to be treated?
Tar containing asphalt contains contaminants, particularly polycyclic aromatic hydrocarbons (PAHs). For this reason, the material is classified as hazardous waste and cannot be reused without further treatment. Appropriate processing removes the contaminants and enables the recovery of valuable mineral raw materials. This allows the materials to be reused and reduces the need for alternative disposal routes.
How does the NaRePAK asphalt treatment process work?
In the NaRePAK process, PAH contaminated asphalt is treated in a thermal process at temperatures of approximately 570 to 600°C. During this process, the organic contaminants are removed while the mineral components remain intact. Thanks to the gentle treatment conditions, the recovered aggregate can subsequently be reused in the production of asphalt and concrete. The flue gases generated during the process are cleaned, and the system also enables heat recovery.
Which raw materials can be recovered using the NaRePAK process?
The NaRePAK process recovers the mineral components contained in tar contaminated asphalt. The treated aggregate can then be reused as a raw material in the production of asphalt and concrete. This keeps valuable mineral resources within the material cycle and enables their reuse in new construction applications. The process developed by Eisenmann Environmental Technology was specifically designed to maximize the reusability of the recovered aggregate.
Can the treated materials be reused in asphalt and concrete?
Yes. The NaRePAK process has been developed to enable the recovered aggregate to be reused almost completely. The treated materials can be used as aggregate in both asphalt and concrete production. This allows valuable mineral raw materials to be recovered and returned to the production of new construction materials. Eisenmann Environmental Technology has specifically designed the process to achieve high quality raw material recovery.
What are the advantages of the NaRePAK process compared to landfilling or thermal disposal?
The NaRePAK process enables the treatment of PAH contaminated asphalt materials while recovering the valuable mineral resources they contain. Unlike landfilling, the recovered materials remain in the material cycle and can be reused. The process also incorporates heat recovery and flue gas cleaning. By using the bitumen contained in the material as an energy source, the process can operate in a nearly autothermal mode, meaning that the need for additional energy input is significantly reduced.
How much tar contaminated asphalt can a NaRePAK plant process?
A NaRePAK plant can process up to 135,000 tonnes of tar contaminated asphalt per year. The plant concept is designed for regional material recovery and enables the treatment of large material volumes on an industrial scale. Its regional approach can also help reduce transportation distances.