Research On Gold And Silver Recovery During Oxygen-enriched Bottom-blown Copper Smelting

In view of the low recovery rate of gold and silver produced by sulfonium capture in the oxygen-enriched bottom-blown copper smelting process,the relevant references were consulted and this study was proposed.Combined with production,the process mineralogical research of raw materials was carried out,and the behavior and trend of gold,silver and copper in the process flow were examined.It was pointed out that sulfide-coated gold accounts for 64.71%,silicate-coated gold accounts for29.41%,and bare gold accounts for 5.88%.It is known that smelting copper concentrate with high lead content and high-grade matte copper output will cause gold and silver to be distributed in smoke and slag with lead volatilization in the smelting and blowing section.FactSage7.3 software was used to calculate the multiphase balance and phase diagram of bottom-blown copper smelting slag,combining the effects of CaO and MgO content on the melting temperature,melting amount and viscosity of the smelting slag and the content of CaO,MgO and Fe O on Fe O-Si O₂-According to the influence of each phase region of the quaternary system CaO-MgO,when the melting temperature of the slag in the oxygen-enriched bottom blowing smelting process is less than 1220?,the suitable slag type for maximizing the recovery rate of gold and silver is:Fe O:20?25%;CaO:7?8%;MgO:4?5%;Si O₂:33.75?47.5%.Based on the above analysis,by controlling the Fe/Si O₂ at 1.6?1.8,adding 3?5%CaO for batching,the original Fe O-Si O₂ binary slag type based on fayalite was adjusted to CaO-based Si O2-Fe O-CaO ternary slag type,adjust the appropriate oxygen material ratio CaO/MgO=1.7,smelting temperature is controlled at 1180?1200?,make full use of the intermediate products in the smelting process and a series of operating measures to make gold and silver recovery The rate has been improved,the final gold recovery rate is 97.61%,silver recovery rate is 97.30%.