The ADIR consortium collected EOL MPHs and server PCBs, studied the range of model variants, and carried out detailed chemical analyses of electronic components and modules of MPHs and PCBs using various classical analytical methods. Moreover, positions and volumes of these components are determined as a decision basis which components are of interest for a selective disassembly in terms of material value.
Older generations of MPHs as well as new generations were considered. The advisory board provided recommendations with respect to the need for the recycling line to meet both legal and environmental European requirements, potential for extraction of raw material as well as parts that can be re-used and to prioritise by material not only with economic but also environmental considerations.
To gain a first profound data basis thirteen different models of mobile phones as exemplary samples were analysed in detail. All models were dismantled manually, the electronic components of the PCBs were extracted and analysed by a screening X-ray fluorescence (XRF) method. The complete PCBs with the electronic components were also analysed. For each of the studied MPHs a data sheet was created and documented. It contains photographic data of the disassembled phones and results of the XRF screening analysis of all electronic components, the residual bare PCB and external modules (such as vibration alert, camera etc.). Tables with ranked components and modules as well as their estimated target metal contents were compiled.
Based on the determined composition of the components and the knowledge available within the consortium preselection criteria for extraction of components were defined. In view of the economical aspect of recycling it is essential to extract the components which contain gold, palladium, silver, tantalum, tungsten and neodymium. The value of gold is about 85 % of the total value of target elements present in components dismantled from PCBs of MPHs. Based on these studies the following sorting fractions for a selective dismantling by the ADIR demonstrator to be set-up were recommended: 1) all components which contain Au; 2) all components which contain Ta and W; 3) components which contain Nd; 4) components which contain other target elements not covered by 1) – 3).
The following processes were studied and developed for a selective piece-by-piece treatment of EOL MPHs and PCBs and the processing of the novel sorting fractions:
- pre-sorting and singularisation of input material,
- image processing to recognise model types, orientations, positions of MPHs, PCBs,
- robotic handling of MPHs and PCBs: picking, transfer,
- dismantling actions for MPHs to extract battery and PCB,
- training of dismantling actions by test sets, working out sets of dismantling recipes,
- detailed imaging of PCBs to localise position and volume of electronic components,
- fast laser-based chemical analysis of selected electronic components to identify components with high concentrations of target elements,
- fast selective laser-based desoldering or cut out of identified electronic components,
- pulsed-power treatment of partially dismantled MPHs and PCBs to extract further valuable components,
- sorting of extracted components and modules in fractions,
- metallurgical processes adapted to pre-concentrated novel sorting fractions.
Based on these processes the worldwide first inverse production line comprised of seven machines was developed and set-up in a recycling plant of the consortium partner Electrocycling GmbH, Goslar, in Germany. The line – called ADIR demonstrator – is able to work in two different operation modes: a) manual loading of PCBs (from MPHs or from servers) and b) automatic loading, where mobile phones are conveyed from the feeding station to the dismantling station.
The various machines and their functions are:
Machine 1 – feeding and singularisation
Machine 2 – dismantling of MPHs, extraction of battery and PCB
Machine 3 – manipulation of PCBs among the machines
Machine 4 – desoldering and sorting of electronic components
Machine 5 - measurement of the 2D/3D geometry of PCBs and laser spectroscopic analyses
Machine 6 - fragmentation of residues from MPH dismantling and PCBs
Machine 7 - recognition of output of fragmentation machine 6 to identify vibration alerts
In field tests with the ADIR demonstrator nearly 2000 items have been processed, new sorting fractions with high enrichment of target metals were generated and recovery rates of > 95 % for target elements were shown. The results were presented on two demo days, as well as in trade fairs, scientific conferences and publications to a broad audience. The results are planned for exploitation of the demonstrator line as a whole but also of the individual processes.
