Institute Technology Solves Recycling Challenges of Retired Photovoltaic Modules

On September 11, the Hunan Institute of Scientific and Technical Information hosted a scientific and technological achievement evaluation meeting in Changsha for the project on combined processing technology and equipment for the intelligent dismantling, environmentally sound separation and clean extraction of retired photovoltaic modules, completed by the Changsha Research Institute of Mining and Metallurgy. A review expert panel led by Academician Qiu Guanzhou of the Chinese Academy of Engineering unanimously concluded that the project's overall technology has reached a world-leading level.

Addressing industry challenges including complex conventional recycling processes for retired PV modules, difficulty in intelligent identification and precise dismantling, low dismantling and sorting efficiency, difficulty in environmentally sound removal of fluorine-containing backsheets and low silicon wafer and glass separation indices, the project team successfully developed combined processing technology and equipment for intelligent dismantling, environmentally sound separation and clean extraction of retired PV modules.

The team creatively developed a combined system for silicon and silver recovery from waste silicon wafers, overcoming key technologies for clean silicon-silver extraction based on full-fraction silver extraction, deep aluminium removal and silicon nitride. This breaks through the limitation of conventional methods that can only recover coarse-fraction waste silicon wafers, achieving efficient separation and purification of silicon, aluminium and silver metals, with recovered silver powder purity of at least 99% and recovery rate of at least 95%.

The project has been granted 24 patents, including 12 invention patents and 12 utility model patents, and has published five papers.