WAVE

Analysing secondary raw materials using microwave-assisted laser emission spectroscopy

The project "WAVE"” realized a mobile laser analysis to sort and separate metal scrap. To this end, the combined excitation of laser and microwave radiation without hollow cavity was examined for the first time. The aim was to realize a light-weight and therefore mobile yet efficient analytical system.

Recycling metal scrap is becoming increasingly important due to the rising demand for raw materials needed to produce metals. The composition of the scrap metal must be known for material-specific recycling without loss of quality. This makes incoming and outgoing goods inspections in recycling companies essential and requires mobile, hand-held and fast analyzers.

Mobile analysis, which is currently used, is unable to deal with all elements and microparts. Preparing samples is also very costly. Highly sensitive analysis systems based on variable laser emission spectroscopy are still too large and heavy for mobile applications.

The "WAVE" project combined laser and microwave radiation without hollow cavity in the laboratory for the first time. This promises increased efficiency, at the same time the system remains mobile due to its light weight. It was possible to implement the results into a compact, mobile laser-based analyzer which can identify different metal alloys. The mobile system is equipped with a handheld analyzer which weighs 2.3 kilograms and can therefore be used at any location. It can identify metals and non-metals within five milliseconds which makes sorting highly efficient and can detect objects the size of a few millimeters.

As it is no longer necessary to prepare the materials, and only one instead of several appliances is used, measuring time has become significantly shorter. This saves time and therefore sorting secondary raw materials has become more efficient. Using the new measuring instruments means that different types of metal alloys can be sorted and recycled and usable alloys can then be generated. This reduces the metallurgical expense when producing alloys and lowers the demand for primary metals. Sorted scrap metal has a significantly higher price than unsorted scrap metal – for example for aluminum the difference is several hundred euros per ton. Per instrument 500 tons of sorted aluminum scrap can be produced annually in the case of 100 percent testing of all components. Recycling materials and the subsequent secondary production could save more than 10,000 tons CO2. The project tested this system in the metal recycling industry for high-quality steels and aluminum alloys. However, the system can be used for almost any type of metal.


Document (only in German)

Contact

M. Sc. Michael Scharun
Fraunhofer-Institut
für Lasertechnik ILT
Phone: +49 (0) 241 8906-196

Federal Ministry of Education and Research
Fona - Research for Sustainability
Project Management Jülich - Research Centre Jülich
Fraunhofer Institute for Systems and Innovation Research