Liberation of various types of composite materials by controlled underwater explosion

Controlled underwater explosions of various composite materials (i.e. discarded DVDs, end-of-life mobile phones, tungsten carbide scrap as well as concrete slabs) were carried out in order to indicate the potential of this novel technique in liberating valuable components for recycling. The great advantage of the underwater explosion is especially noticeable where excessive comminution needs to be avoided in order to increase the degree of liberation or reduce the size of hazardous or composite materials. The main finding of this work is that a controlled underwater explosion, a contactless method, ensured the liberation of valuable components from the mounting matrix by generating enough pressure in solids during the transfer of the pulse through the medium (i.e. water). In other words, high-pressure pulses induced the liberation of valuable components that have a boundary with less valuable matrix. (C) 2016 Elsevier Ltd. All rights reserved.