A PROCESS FOR THE RECOVERY OF METAL VALUES FROM WASTE PRINTED CIRCUIT BOARDS

摘要

The present invention recites a simple process for the processing of waste printed circuit boards to separate metal values from non-metallic constituents. The undesirable attachments are first removed from the boards and the boards are then shredded into small pieces. These pieces are ground in a tumbling mill. A classifier is used to remove the fine particles containing very little metal values. The coarse fraction then is treated in a gravity separator to separate the heavy metallic components from the light resinous plastic material of the boards. The products of gravity separation are then treated in flotation process to further purify the heavy metal rich fraction. The products of flotation step are treated in enhanced gravity separator to remove lighter plastic particles from the product further. The valuable product is then conveniently dried up for further purification steps. The dried valuable product is treated in electrodynamic separator to obtain a further metal rich conductive fraction and a small non-conductive fraction of plastic material. Another electrostatic separation step is performed to obtain a very pure metallic conductive fraction and a small, purely non-conducting non-metallic fraction.