Optimization of Process Parameters for Flowing Film Concentration of Ground Printed Circuit Boards

Abstract

Printed circuit boards, incorporated in most electrical and electronic equipment, contain valuable metals such as Cu, Ni, Au, Ag, Pd, Fe, Sn and Pb, etc. The circuit boards are rich in metal content and the need for processing these wastes to extract the metals values and remove the non-metallic constituents has been felt all over the world. It was evident from size-wise chemical analysis of the ground PCBs that the particulate system is quite rich in metal value with about 23% of the total powder being metallic. It contained 12.8% Cu, 2.4% Pb, 1.2% Sn, 2.5% Al and 0.5% Ni. This paper summarizes the effect of operating variables of crushed PCB waste using Wilfley Table. Detailed experimentation has been performed with crushed printed circuit boards according to a Box-Behnken design of experiments to establish the influence operating variables on the separation performance. The optimized conditions for maximizing the yield of the metal values with respect to the specified grade of the concentrate were discussed in the light of the experimental results.