Cryogenic delamination : mathematical modeling and analysis of an innovative recycling process for photovoltaic crystalline modules

The increasing rate of production and diffusion of photovoltaic (PV) technologies for industrial and domestic applications urges improvement of the sustainability of their demanufacuring processes in order to reduce the amount of electronic wastes. Sustainability of demanufacturing processes concerns the reduction of energy consumption, the reduction of polluting substances as well as the reduction of the effort spent in recovery of the components. No optimal process exists so far, provided a number of different approaches have been devised. A promising choice relies on the use of thermo-mechanical treatments for inducing a delamination process where interfacial bonding between layers are weakened and, finally, broken inducing delamination of the layers. In this view, the paper presents a preliminary theoretical industrialization study. We introduce a mathematical model based of the equations of thermo-elasticity to prove the feasibility of the technological process; the results of a Finite Element (FE) Analysis are then discussed to show the validity of the new sustainable demanufacturing process endeavouring the delamination process. The analysis is performed searching the optimal thermally induced cycles at cryogenic temperatures.