Circular Asphalt Production - Optimising recycled asphalt usage in Denmark
Project start June 2015. Completed June 2017.
This project aims at improving resource savings through the development of a sustainable road construction concept for the Danish road market. Asphalt is produced from natural resources and is 100 % recyclable. Thus, it may take part in a circular material flow to help reduce the use of natural aggregates and bituminous binders derived from crude oil, which is one of nature’s limited fossil resources. In today’s scenario, however, only a limited part of reclaimed, broken-up, or milled-off asphalt finds its way back to the production of new asphalt; whereas a relatively large part is downcycled and re-used as replacement for unbound gravel base courses, among other secondary applications. In this light, the valuable bituminous binder from old asphalt is not exploited properly, which is a scenario that cannot persist. The novel concept developed in this project combines milling-off layer-by-layer, source-separated storage of the reclaimed asphalt, and new processing methods to promote efficient asphalt upcycling. This will enable increasing the circular material flow and the use of reclaimed asphalt in pavements with the highest value and potential; specifically, the coarse-graded wearing courses with the highest quality requirements. The project will ensure that the developed concept is robust, without compromising pavement durability and functionality, allowing for introducing the developed concept on municipal roads safely. Sustainability improvements will be evaluated and documented through LCA and LCC analyses. Finally, guidelines for optimized implementation of the new techniques will be produced as basis for introduction to the Danish Road Regulation committee.
- Develop a new concept for milling, handling, storage and recycling of reclaimed asphalt to promote a circular material flow
- Produce high-quality asphalt wearing courses with reclaimed asphalt (at the presently given maximum share) without compromising durability and performance
- Document that the present maximum recycled asphalt share in wearing courses may be increased without compromising durability and performance.
- Evaluate the sustainability improvements promote by new production techniques
- Prepare guidelines for the implementation of the new technique as basis for introduction to the Danish Road Regulation committee.
- Danish Asphalt Industry, DK
- Danish Road Directorate, DK
- Danish Technological Institute (Project Manager), DK
- Local Government Denmark (LGDK), DK
- Lemminkäinen, FI