Ramezani Hamed, Kamran Haghighi Hossein
Department of Mining Engineering, Amirkabir University of Technology, Tehran, Iran.
Sci Rep. 2025 Aug 26;15(1):31423. doi: 10.1038/s41598-025-17360-z.
This study aims to float lead from the lead smelting slag of a Kaldo furnace. The slag characterization showed that the slag consisted of galena, quartz, metallic lead, sphalerite, and pyrrhotite (10.3% Pb, 5.1% Zn, and 20% Fe). Flotation experiments were conducted on the slag using potassium amyl xanthate (PAX), zinc sulfate, and sodium cyanide. Increasing the concentration of PAX improved lead recovery due to the oxidation of the xanthate ion. Due to the particles engaged, zinc sulfate and sodium cyanide were not effective in depressing zinc and iron, and often resulted in the depression of lead. Under optimal conditions of 800 g/ton PAX, 250 g/ton zinc sulfate, and 50 g/ton sodium cyanide at a pH of 9.5, a lead concentrate containing 21.5% lead with a recovery of 61.17% was obtained, alongside zinc and iron recoveries of 45.34% and 26.76%, respectively. Given the 1200 °C operating temperature of the Kaldo furnace and the melting points of lead, zinc, and iron, lead and zinc are more susceptible to changes in physical and chemical properties and to form an alloy. This is a significant factor contributing to high zinc recovery in lead concentrate.
本研究旨在从卡尔多炉铅冶炼炉渣中浮选铅。炉渣表征显示，炉渣由方铅矿、石英、金属铅、闪锌矿和磁黄铁矿组成（含10.3%的铅、5.1%的锌和20%的铁）。使用戊基黄原酸钾（PAX）、硫酸锌和氰化钠对炉渣进行了浮选实验。由于黄原酸根离子的氧化作用，提高PAX的浓度可提高铅的回收率。由于颗粒相互作用，硫酸锌和氰化钠在抑制锌和铁方面效果不佳，且常常导致铅的抑制。在PAX为800克/吨、硫酸锌为250克/吨、氰化钠为50克/吨、pH值为9.5的最佳条件下，获得了含铅量为21.5%、回收率为61.17%的铅精矿，同时锌和铁的回收率分别为45.34%和26.76%。鉴于卡尔多炉的运行温度为1200°C以及铅、锌和铁的熔点，铅和锌更容易发生物理和化学性质的变化并形成合金。这是导致铅精矿中锌回收率较高的一个重要因素。
