Electrodynamic fragmentation-based concrete recycling
Although it is possible to recycle concrete, the process typically involves breaking the material down into aggregates that are used as a crude material for roads and other infrastructure. This downcycling prevents an ideal full recovery of the original material for a wide variety of new applications.
Researchers from the Holzkirchen, Germany-based Concrete Technology Group at the Fraunhofer Institute for Building Physics IBP have revived a technique that enables such a recovery. Invented and later abandoned by Russian scientists in the 1940s, the process, called electrodynamic fragmentation, involves subjecting the concrete to artificially triggered lightning bolts. This method allows the material to be separated into its individual components of aggregate and cement. The process works by submerging the material in water and introducing an electrical charge, which seeks the path of least resistance through the material, around component boundaries.
The method currently requires one hour for each ton of recovered concrete, but the scientists estimate a future processing speed of twenty tons per hour. According to lead researcher Volker Thome, lighting-processed concrete will enable an efficient concrete recycling rate of 80 percent, which is ten times the current amount.
Contact: Fraunhofer Institute for Building Physics IBP, Holzkirchen, Germany.
For more information, see Transmaterial Next: A Catalog of Materials that Redefine Our Future