Thermal delamination – meaning the removal of polymers from the module structure by a thermal process – as a first step in the recycling of crystalline silicon (c-Si) photovoltaic (PV) modules in order to enable the subsequent recovery of secondary raw materials was investigated. A correlation between treatment temperature and duration was established by an iterative process. Furthermore, chemical characterization of the resulting solid outputs (glass, cell, ribbons and residues) was performed in order to assess their further processing options. Additionally, the effect of removing the backsheet as a pre-treatment before the actual delamination process was investigated in relation to the aforementioned aspects of treatment duration and output quality. Results show that increased temperatures reduce the necessary treatment duration (65 minutes at 500°C, 33 minutes at 600°C) while generating the same output quality. The backsheet removal leads to an additional duration decrease of more than 45% at each considered temperature, while also having positive effects relating to fewer solid residues and easier flue gas handling. In regard to the main output specifications no significant influence of the pre-treatment is observed. Overall thermal delamination can be seen as a feasible method in order to obtain high value secondary raw materials from c-Si PV modules, while backsheet removal as pre-treatment should be considered as advantageous from multiple standpoints.

In recent years the end-of-life (EOL) management of photovoltaic (PV) panels has started to attract more attention. By including PV panels in the WEEE Directive in 2012 the European Union has introduced a concrete legislative framework regarding EOL for this sector. Several research investigations into specialized PV recycling processes have been conducted over the last years, although very few of the findings have been implemented on a commercial level up to now. Nowadays, recycling usually still takes place in general recycling plants for flat glass or waste electronics. In this work, the current situation regarding EOL management of PV panels in Austria is analysed by literature research and interviews with stakeholders relevant to the EOL of PV panels. The legislative framework (including national peculiarities) and its influence on current procedures regarding collection and subsequent treatment is shown. Furthermore, current recycling processes are described and a country specific prognosis model is created to assess the future development of waste quantities. Results show that the amount of PV panel waste arising in Austria at the moment is very small and therefore no dedicated recycling takes place. However, quantities will considerably rise in the upcoming years and will act as the main driving force for the implementation of an improved EOL management system including specialised recovery processes.

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