In view of growing demands for ecological and economic efficiency, the sustainable utilization of raw and recycled materials is becoming increasingly important. Sorting processes of material flows are of particular importance: Indeed, purity aspects in the raw or recycled material feed often play a significant role in the energy and time required in the actual processing and refining, as well as the quality of the end products. Both hyperspectral and multispectral imaging are ideally suited for these purposes and are therefore increasingly being used.
By analyzing the spectrum of objects in the material stream, for example on a conveyor belt, it is possible to:
- verify the material composition of individual components.
- detect impurities.
- evaluate the quality of manufactured products.
Plastics recycling is a major challenge, since there are different recycling processes depending on the basic material used, for example PE, PP or PVC, which preserve the specific properties of the material in question. Therefore, they must be separated by type as much as possible in order to recycle them effectively. This applies to shredded flakes as well as to whole plastic parts such as plastic bottles. Apart from the polymer type, hyperspectral imaging can also detect aggregates or coatings that affect recycling behavior. This enables the sorting out of unsuitable materials or the adjustment of certain mixing ratios.
Many industries require continuous control of all production steps to ensure high quality requirements for the end product. In most cases, the control steps are carried out on a random basis or by means of time-consuming laboratory tests, which sometimes result in a considerable hold time of the process and thus ineffectively tie up production capacities. Hyperspectral or multispectral imaging methods can be used in many places to record the production process in real time and to detect deviations between target and actual conditions. In this way, defective parts or batches can be detected and rejected early in the process, and process parameters can be adjusted to minimize time-, material- and cost-intensive misproductions.
Application areas that particularly benefit from such processes:
- Pharmaceutical products: Composition, active ingredient content and distribution
- Inline inspection of packaging for damage
- Moisture determination in wood, paper, textiles, etc.
- Control of coatings, adhesions