| Название |
A study of electronics scrap material composition and ways of its valuable components release intensification in disintegration |
| Реферат |
Electronics miniaturization complicated the application of physical and mechanical methods for electronics scrap salvaging, and intensified the need for its disintegration prior to separation processes. Copper, as the main heavy metal present in most of valuable components of electronics scrap, is comparatively uniformly-distributed in medium size fractions. This indicates its insufficient release in crushing process in hammer-type crusher. The task of selective release of this type of laminated structure consists in separation of copper foil from polymer matrix. For the purpose of copper release improvement, the process intensification methods, based on difference in composite components’ temperature coefficient of thermal expansion, are proposed. In order to achieve thermal shock for printed-circuit boards, the three methods of their heating were compared: using SHF-heating, HFC-heating and convection heating in muffle-type furnace. Effect of heating with respect to printed-circuit boards release in crushing in hammer-type crusher was studied. It was confirmed that heating of printed-circuit boards permits to intensify copper foil — polymer matrix release. Treatment with HFC (50–100 kHz) provides for practically complete release of copper foil — polymer system, with that, printed-circuit boards temperature does not exceed +50 °С, which is an undeniable advantage over other methods, as cooling is not required prior to subsequent treatment.
The work was performed with the aid from the Ministry of Education and Science of the Russian Federation, the Government Agreement No. 14.585.21.0007. UIPNI RFMEFI 58516X0007. |
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