Pure Silicon Recovering from Photovoltaic Modules

Photovoltaic technology is worldwide used to provide reliable and cost-effective electricity for industrial, commercial, residential and community applications. The average lifetime of PV modules can be expected to be more than 25 years. The disposal of PV systems will emerge as a problem, considering the still increasing production of PV modules. Recycling of such modules can be done at about the same cost level as its disposal. Recovering the pure silicon from damaged or end-of-life PV modules can lead to economical and environmental benefit. Chemical treatment conditions need to be precisely adjusted in order to achieve the required purity level of the recovered silicon. For crystalline silicon based PV systems, a series of etching processes has been carried out as follows: electric connectors (etching or removing), ARC and n-p junction etching. The chemistry of etching solutions was individually adjusted for the different silicon cell types. Efforts were taken in order to formulate a universal composition of etching solution.