Researchers at Australia's University of New South Wales (UNSW) claim their patented sieving process can effectively extract 99% of PV cell particles during the recycling process for reuse, especially silver, at high efficiency within 5 to 15 minutes. During the tests carried out by the team, it was able to recover around 0.64 kg of silver/ton of PV waste.
The new process developed by the Shen lab of Process Modelling and Optimization of Reacting Flows (ProMo), led by Professor Yansong Shen, can recycle between 5 to 50 million kg of silver from the cumulative waste by 2050 which it believes can grow up to 78 million tons.
Process developed over the last 3 years brings together traditional methods with a highly abrasive separation system using sieving aids, using stainless steel as the metal of choice.
According to Professor Shen, the process begins with the removal of large components as aluminum frame and glass sheets, followed by crushing the panel and separating the material inside the cell. All of this is carried out in a vibrating container.
He explains, "The key to our new process is the addition of the sieving aids which help to crush the solar cells into smaller particles allowing a better separation of all the components. That makes it much easier to recover important elements such as the silver contained in the solar cells."
Material extracted can then be separated using a traditional chemical leaching method and precipitation to extract pure silica and silver and other specific materials.
The team said it is working on other steps beyond lifecycle assessment, and is open to more industry collaborations to scale the process and enhance economic feasibility of the PV recycling process.
Research work of the ProMo team is backed by grants from the Australian Renewable Energy Agency (ARENA) and New South Wales' Environmental Protection Agency (EPA) (see ARENA Funding To Improve Solar Panel Efficiency).
Australia is taking a serious view of solar panel recycling as some 80 million of these are expected to end up in landfills over the next 20 years, as ascertained by a research work by the UNSW, University of South Australia (UniSA), Solarcycle and Circular PV Alliance (see Research Recommends End-Of-Life Legislation For PV Panels).
Solar panel recycling was part of the discussion on Solar & Sustainability during TaiyangNews virtual conference in March 30, 2030. Details about the various presentations during the event and a conference summary report are available on our website here.