Research and industrial application of a vacuum separation technique for recovering valuable metals from copper dross

A novel, clean and highly efficient vacuum separation technique for the commercial processing of copper dross is introduced in this article. The industrial treatment of 500 kg copper dross showed that under the conditions of 1523 K, 20–150 Pa and 5 h of heat preservation, three kinds of products can be obtained by vacuum distillation, namely, crude lead, lead sulfide, and a Cu-As-Sb alloy. During the process, waste gas and wastewater were not generated, and no reagents were added. The combined power consumption is less than 1500 kW·h/t. The process was perfectly coupled to the lead smelting system, and the product was returned to the main process without the need for additional equipment to process it separately.