PURPOSE: To recover a high-grade metal such as copper from a circuit board such as a copper-clad laminate at a high recovery rate.
CONSTITUTION: A circuit board 1 is dry-distilled at 500-1000°C in a reducing atmosphere. The residue 5 is cooled to a temp. at which the residue is not rapidly oxidized even by contact with the atmosphere. The cooled material 7 is crushed. The crushed material 9 is classified into a metal such as copper 11 and a base material component such as glass 12. The gaseous distillate 4 generated in the first stage is burnt, and a part of the combustion gas is used as the heat source. Meanwhile, the heat of a part of the combustion gas is recovered, and the combustion gas is supplied as the inert gas in dry distillation.
TANAKA YUKIRO
BABA HIDETOSHI
INOMAKI TOORU
SAKUMA YUKIO
ASHINO YUKIHIRO
TANIGUCHI KATSUHIRO
OKUMURA KAZUO
KIMURA KAKOKI CO LTD
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