Reclaiming materials from scrap electric wires - where compacted scrap is cooled in liq. nitrogen to embrittle insulation, then burst by explosive and sieved

摘要

Scrap is pressed into a stable compact of prescribed size contg. a hole for an explosive charge. Compacts are then cooled to a very low temp. to embrittle the insulation materials on the cables, followed by detonating an explosive charge in each compact, thus producing numerous small pieces which can be sorted into individual materials. Compacts are pref. suspended freely in an explosion chamber in which the vol. ratio chamber:compact is min 200:1, and esp. 500:1 to 700:1. Use of 15-20 g. hexogen per kg. scrap produces a sepn. of 80-98% of the insulation material, and process also using 1 kg. liq. N2/kg. scrap.