my country's scientists propose True airborne condensing technology to recover PET and EVA in solar cells

　　Author ：Iflowpower – Portable Power Station Supplier

Scientists from Sun Yat-sen University and Shanghai Jiaotong University proposed a vacuum-fired condensing technology to recover polyethylene terephthalate (PET) and ethylene-vinyl acetate (EVA) in solar cell board. Recycling at the end of the cycle. Both materials are used in solar panel packaging photovoltaic manufacturing.

Scholars claim that existing PET and EVA recycling technology are based on the use of chemical solvents, which will cause secondary pollution. Instead, their new technology claims to convert PET and EVA high value-added products and energy materials that have no secondary pollution. These two materials account for approximately 15% of the total material of the waste solar cell, of which EVA and PET account for 10% and 5% respectively.

During this process, the Chinese Group used a vacuum furnace provided by China Experts Algrant Co., Ltd., which consists of vacuum iong, vacuum mechanical pump, diffusion pump and control panel.

Copper, tin, silicon, silica, etc. are all brittle materials, which are pulverized into particles having a particle size of less than 5 mm, and the particles of PET and EVA belong to the tough material. It cannot be broken by the crusher, and is broken into larger particles, particle size.

Between 5mm to 20mm. PET and EVA are completely decomposed when the furnace temperature reaches 490 ¡ã C. "More than 490 degrees Celsius, no change in weight, indicating that PET and EVA have completely decompose and volatilize," scientists said.

"At 297-386 degrees Celsius, the mixed weight of PET and EVA has slowed down, indicating that the length of PET and EVA is broken at this stage. At 386-490 degrees Celsius, the quality loss of the decomposition process is fastest at 461 degrees Celsius. "When the temperature reaches 505 degrees Celsius, the internal pressure is restored to the initial level, PET and EVA are completely decomposed.

Through this process, the total residual amount is 1.95kg, mainly composed of blockage particles and spherical particles. The proportion of carbon is up to 42.

35%, followed by silicon, 36.99%, silver is 11.41%, oxygen is 6.

63%. Scientists added: "There are also small amounts of copper, iron and zinc in the residue. The residue contains a lot of aluminum because the aluminum electrode covers the surface of the solar cell chip.

"This paper describes the process of recovering polyethylene terephthalate and ethylene-vinyl acetate copolymers in waste solar cells in a new vacuum gas condensation process, published on ACS publication.