摘要
Synthetic dyes are commonly used for graphite depression in poly-metallic flotation circuits; however,these dyes can be very expensive. The aim of this study is to evaluate performance of certain low-cost alternative depressants for a complex lead-zinc(Pb-Zn) ore rich in graphite(Gr-C) on a conventional mini pilot-scale flotation circuit. The reagents used were commercial and industrial grade starch; agro-based waste-sugarcane bagasse and charred(burnt) bagasse powder. The primary evaluation criteria were quality(grades) of lead and zinc concentrates, their recoveries(%), and graphite rejection(%) in the tails.Benchmark tests using nigrosine as graphite depressant showed 94.3% rejection of Gr-C. The results with commercial starch were found as effective with 93.8% graphite rejection. Furthermore, bagasse powder showed potential in improving product quality(36.4% and 65.6% Pb grade and recovery) with an intermediate effectiveness in graphite rejection(85.6%). The order of effectiveness in Gr-C rejection follows nigrosine % commercial starch > bagasse > industrial starch > charred bagasse. In addition, the effect these depressants on silver(byproduct) grade and recovery was also investigated.
Synthetic dyes are commonly used for graphite depression in poly-metallic flotation circuits; however,these dyes can be very expensive. The aim of this study is to evaluate performance of certain low-cost alternative depressants for a complex lead-zinc（Pb-Zn） ore rich in graphite（Gr-C） on a conventional mini pilot-scale flotation circuit. The reagents used were commercial and industrial grade starch; agro-based waste-sugarcane bagasse and charred（burnt） bagasse powder. The primary evaluation criteria were quality（grades） of lead and zinc concentrates, their recoveries（%）, and graphite rejection（%） in the tails.Benchmark tests using nigrosine as graphite depressant showed 94.3% rejection of Gr-C. The results with commercial starch were found as effective with 93.8% graphite rejection. Furthermore, bagasse powder showed potential in improving product quality（36.4% and 65.6% Pb grade and recovery） with an intermediate effectiveness in graphite rejection（85.6%）. The order of effectiveness in Gr-C rejection follows nigrosine % commercial starch 〉 bagasse 〉 industrial starch 〉 charred bagasse. In addition, the effect these depressants on silver（byproduct） grade and recovery was also investigated.
基金
The author is grateful to the management and staff of Center Research Development laboratory(HZL,Debari),India for their support with this research and permitting to publish the work.
