中国有色冶金

Lead-silver slag contains lead, zinc, silver and other valuable metals, and the treatment process should achieve two purposes: valuable metal recovery and harmlessness. The leached residue from hydrometallurgical treatment process is still hazardous waste; in the pyrometallurgical treatment process, the more advanced Kivcet process and Ausmelt process, together with lead concentrate process to treat lead and silver slag, however, there exist issues like high production and construction costs. This paper introduces a process of co-processing lead-silver slag from zinc smelting and lead concentrate through oxygen bottom blowing smelting. The theoretical calculation shows that if the composition of lead concentrate and lead-silver slag in a smelter is typical, and under the premise that fuel is not required for oxidative smelting, the maximum value of lead-silver slag is 13%. According to practical production data, the lead recovery rate of this process exceeds 98%, the zinc recovery rate exceeds 90%, the silver recovery rate exceeds 98.5%, and the resource recovery rate is remarkable; The coal consumption is 260-330kgce/t, which realizes low-carbon treatment of lead and silver slag; the off gas generated by the process is used for acid production, the dust is returned to the smelting furnace for comprehensive recovery, and the slag can be sold directly to the cement plant for comprehensive utilization, which means the goal of harmless treatment has been achieved.