The growing volume of end-of-life (EoL) photovoltaic (PV) panels presents a significant challenge and an opportunity for sustainable resource recovery. This thesis investigates the application of Magnetic Density Separation (MDS) to recover and separate valuable non-ferrous metal
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The growing volume of end-of-life (EoL) photovoltaic (PV) panels presents a significant challenge and an opportunity for sustainable resource recovery. This thesis investigates the application of Magnetic Density Separation (MDS) to recover and separate valuable non-ferrous metals, such as silicon, copper, zinc, tin, and silver, from crystalline silicon PV waste. The objective of the study is to evaluate the separation efficiency and recovery rates of MDS while addressing economic feasibility and process optimization challenges.
The experimental work involved the use of MDS to fractionate PV waste into light, medium, and heavy-density ranges based on particle size distributions: 200–500 µm, >500 µm–3 mm, and >3 mm-6 mm. X-ray fluorescence (XRF) was employed to analyze the elemental composition of the separated fractions, with leaching processes using hydrochloric acid (HCl) and citric acid applied to assess the purity of magnetic samples. Calibration and instrumental errors, as well as the effects of alloying and particle motion, were accounted for in the analysis. A financial assessment of the MDS process was conducted, examining revenues generated from metal recovery and associated costs, including the economic implications of contamination and refining. The results revealed that MDS achieved moderate separation efficiencies, with high recovery rates of silica (SiO2) in the form of glass and sand in the light fractions and silver (Ag) and copper (Cu) in the heavy fractions. However, significant contamination was observed due to overlapping densities of alloyed metals, such as Tin-silver-copper (Sn-Ag-Cu) and Zinc-copper (Zn-Cu), and particle agglomeration during feeding. A financial snapshot demonstrated that medium- and large-sized fractions contributed the most to revenue, driven by silver recovery, with a break-even point requiring the processing of at least 114 tons of PV waste. In conclusion, MDS shows significant potential as a low-energy, cost-effective solution for recycling EoL PV panels. However, achieving industrial viability requires addressing contamination issues and optimizing the separation process. Future work should focus on integrating complementary refining techniques and scaling up operations to meet purity standards and economic demands. The study also recommends the need for improved ferrofluid magnetization and alloy-specific calibration to enhance detection limits.