Fragmentation of printed circuit boards by sub-microsecond and microsecond high-voltage pulses

• Published in: Minerals engineering 2022-01, Vol.176, p.107340, Article 107340
• Main Authors: Zherlitsyn, A.A., Alexeenko, V.M., Kumpyak, E.V., Kondratiev, S.S.
• Format: Article
• Language: English
• Subjects: Electric discharge technologies; High-voltage pulse generator; Liberation; Waste PCBs
• ISSN: 0892-6875; 1872-9444
• DOI: 10.1016/j.mineng.2021.107340

•Crushing of PCBs by sub- and microsecond high-voltage (HV) pulses is compared.•Similarity criterion is used for the optimisation of parameters of a HV generator.•HV crushing compared to mechanical has a better metal liberation with larger sizes. The liberation of components from multi-component waste such as printed circuit boards during recycling is associated with the crushing process. High-voltage electric pulse (HVEP) crushing is considered as an alternative to traditional mechanical crushing methods. This study presents research on the possibility of optimising HVEP crushing for printed circuit boards using high-voltage pulses of microsecond and sub-microsecond durations. Four generators were used for crushing with an output voltage of 40–260 kV and a stored energy of 40–500 J. The similarity criterion K was applied to determine the optimal ratio between the generator parameters and the channel parameters. The generators used attained the best distribution of the fractional composition for a sub-microsecond pulse duration and minimal energy costs (11–12 kJ/g) for both pulse durations. The energy costs for high-voltage pulse crushing were still higher than that for mechanical crushing. HVEP crushing produces a lower over-grinding fraction which was confirmed by sieve analysis.