Waste solar panels contain not only high-value materials such as silicon, silver, and aluminum, but also copper that is recyclable and reusable. Copper possesses excellent electrical and thermal conductivity, and is an essential raw material for critical components such as cables, busbars, and junction boxes. So how to get copper from waste solar panel? YUSHUNXIN has consistently focused on solar panel recycling management, and proposed an innovative recycling technology that combines mechanical separation with pyrolysis, which can realize high-purity recovery of copper resources.

How does copper distribute within solar panels?

To efficiently recover copper, you must first understand its form within photovoltaic panels. In typical crystalline silicon photovoltaic modules, copper primarily exists in three forms:

 

tinned copper strips

These are 99.9% pure tinned copper strips responsible for collecting current between solar cells. Each standard component contains approximately 15-20 grams of copper, accounting for over 60% of the total copper resources.

 

copper-core cables

The external connection components utilize copper-core cables containing approximately 80–120 grams of copper. This copper material is relatively independent and easier to separate for recycling.

 

Internal wiring

Some modules incorporate ultra-fine copper mesh wiring internally. Although each individual component contains only 1–3 grams of copper, its fine distribution and tight bonding with silicon wafers and adhesive films make it the most challenging material to recover.

Copper materials connect directly with silicon wafers using lead–tin solder. EVA film wraps the outer layer, while composite backsheets cover the backside. The entire structure undergoes a lamination process that cures the layers into a highly stable composite. This structural characteristic necessitates that copper recycling must undergo a systematic separation process.

How to Get Copper from Waste Solar Panel?

Mechanical processing serves as the core pretreatment method for copper recovery from solar panels, which can create optimal conditions for subsequent extraction.

Get Copper from Waste Solar Panel
Get Copper from Waste Solar Panel Mechanical Recycling

  • First, the frame removal machine automatically separates aluminum frames from junction boxes, which avoids copper-aluminum mixing contamination. The entire board disassembly takes only 45 seconds, which ensures zero damage to copper materials during recycling.

  • Second, in a liquid nitrogen environment at approximately –30°C, the EVA film and backsheet will become brittle. They then go through an electronic waste shredder, which crushes the material into pieces of 5-15mm. At this time, the highly ductile copper brazing strip remains intact, while the silicon wafer and glass are separated according to the specified particle size, achieving physical delamination.

  • Finally, the multi-stage sorting system in PV recycling technology sequentially employs eddy current separator, high-voltage electrostatic separator, and air separator. The recovery rate of coarse copper particles exceeds 96%. After separating fine copper powder by conductivity differences, it can obtain a copper content exceeding 85%. The mechanical pretreatment process achieves a recovery rate of over 90%.

How Does Pyrolysis Improve Copper Extraction Efficiency?

When mechanical methods struggle to fully remove the adhesive layer and plastic film, pyrolysis can then enhance copper recovery rates.

Pyrolysis to Improve Copper Extraction

  • First, the YUSHUNXIN solar panel pyrolysis project solution employs catalytic pyrolysis technology to completely decompose residual organic matter into combustible gases and volatile oils within an oxygen-free environment at 400–500°C, with a copper surface cleanliness exceeding 99%.

  • Secondly, the PV pyrolysis technology employs multi-stage temperature-controlled pyrolysis. It melts the solder within the 300–350°C range and decomposes the adhesive film between 450–500°C. This stepwise heating process prevents copper oxidation. Pyrolysis treatment can raise the recovery rate of fine copper from 85% by mechanical method to more than 95%.

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