金口岭矿铜钼系统于73年投产。设计前做过可选性试验,由于试料未采入碳岩,试验指标均较高。投产初期钼精矿品位达到35％,回收率53％,74年钼精矿品位下降到20％,回收率46～63％。为查明原因,我们于74年底至75年初进行了现场考查及试验研究工作,初步查清钼精矿品位下降的主要原因是原矿中混入“黑石 Jinkouling mine copper and molybdenum system put into operation in 73 years. Design before the optional test, because the sample did not take carbon rock, the test indicators are higher. In the early stage of production, the grade of molybdenum concentrate reached 35%, the recovery rate was 53%, the grade of molybdenum concentrate dropped to 20% in 74 years, and the recovery rate was 46-63%. In order to find out the reasons, we carried out on-the-spot inspection and experimental research from the end of 74 to the beginning of the year 75. The main reason for the initial drop in the grade of molybdenum concentrate was the mixing of "Blackstone