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Guanghui Yan, Junwei Guo, Guangqing Zhu, Zhenxing Zhang, Pengfei Zhao, Zhu Xiangnan, and Bo Zhang (2020)

Liberation enhancement and copper enrichment improvement for waste printed circuit boards by heating pretreatment

Waste Management, 106:145-154.

Crushing is the key part for the recycling technology of waste printed circuit boards (WPCBs). In this study, the breakage and liberation effects of WPCBs was improved by heat pretreatment technology before crushing (HPBC). Based on the test results, 200 °C was found as the safe temperature for the HPBC of WPCBs. The fracture mode, particle size distribution, and enrichment characteristics of WPCBs were systematically studied. The experimental results show that the HPBC changed the breakage mode from longitudinal fracture to horizontal fracture and improved the liberation of metal from non-metal components. During the crushing process, the increase in the heat pretreatment time (30–120 min) and temperature (100–200 °C) can improve the crushing effect of WPCBs and increase the content of crushing products of −0.3 mm by 3.16% and 5.64%, respectively. Compared to the non-metallic components, the metal components have ductility and are difficult to break into −0.3 mm during the crushing process. HPBC can promote copper enrichment to narrow grain size. In the 0.3–1 mm range, the content of copper increased from 47.87% to 57.61%, an increase by 9.74%. The initial enrichment of copper was achieved by adjusting the crushing time. The recovery rate of copper can reach 85.66%, and the enrichment rate is 1.74 when 0.3–2 mm breaking product is used as enrichment. Therefore, HPBC can effectively improve the crushing and liberation effect of WPCBs and improve the enrichment rate, and thus is an effective pretreatment method.

Crushing, Enrichment, Fracture mode, Heat pretreatment, WPCBs

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The Material Limits of Energy Transition: Thanatia

Antonio Valero Capilla, Alicia Valero Delgado and Guiomar Calvo

This book provides a holistic view of raw mineral depletion in the context of renewable energy transistion.

The material limits Thanatia


Thanatia. Los límites minerales del planeta

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 Antonio Valero Capilla and Alicia Valero Delgado interviewed by Adrián Almazán

We need a material transition, not only energetic, that restores nature and effectively reuses materials. Gaia must be cared for by extending life on Earth and slowing its degradation towards Thanatia.

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Thermodynamics for Sustainable Management of Natural Resources

Cover Thermodynamics

Wojciech Stanek (Editor)

This book examines ways of assessing the rational management of nonrenewable resources. Integrating numerous methods, it systematically exposes the strengths of exergy analysis in resources management.

Thanatia: The Destiny of the Earth's Mineral Resources

Cover Thanatia

A Thermodynamic Cradle-to-Cradle Assessment by (author): Antonio Valero Capilla and Alicia Valero Delgado

Is Gaia becoming Thanatia, a resource exhausted planet? For how long can our high-tech society be sustained in the light of declining mineral ore grades, heavy dependence on un-recycled critical metals and accelerated material dispersion? These are all root causes of future disruptions that need to be addressed today.