Resource utilization of hazardous gypsum sludge in oxidation smelting of lead concentrate  

石膏污泥在铅精矿氧化熔炼中的资源化利用

作　　者：PAN Zu-chao RUAN Bo-wen JIAO Fen QIN Wen-qing LIU Wei 潘祖超;阮博文;焦芬;覃文庆;刘维(School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China;School of Civil and Resource Engineering,University of Science and Techology Beijing,Beijing 100083,China)

机构地区：[1]School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China [2]School of Civil and Resource Engineering,University of Science and Techology Beijing,Beijing 100083,China

出　　处：《Journal of Central South University》2024年第9期3103-3118,共16页中南大学学报（英文版）

基　　金：Project(2020YFC1909203)supported by the National Key R&D Project of China;Projects(51974364,52074355,51904339)supported by the National Natural Science Foundation of China。

摘　　要：Gypsum sludge,a hazardous waste generated by the non-ferrous smelting industry,presents a significant challenge for disposal and utilization.To investigate the feasibility of substituting gypsum sludge for limestone as a flux for smelting,the effects of calcium sulfate(CaSO_(4))and smelting conditions on oxygen-rich smelting of lead concentrate were studied.The interaction between CaSO_(4)and sulfides facilitates the conversion of CaSO_(4)into CaO,which is crucial for slag formation.The order of the influence of sulfide minerals on the conversion of CaSO_(4)is pyrite>sphalerite>galena.When using gypsum sludge exclusively as the calcium source,under optimal conditions with a CaO/SiO_(2)mass ratio of 0.8,an FeO/SiO_(2)mass ratio of 1.2,a melting temperature of 1150℃,an oxygen flow rate of 1.3 L/min,the recovery rates of Pb and Zn in the lead-rich slag reached 85.01%and 95.69%,respectively,with a sulfur content of 2.65 wt%.The As content in the smelting slag obtained by reduction smelting was 0.02 wt%.Resource utilization of gypsum sludge in lead smelting is a feasible method.石膏污泥是有色金属冶炼行业产生的危险废物,对其处置和利用有重要意义。为了探究采用石膏污泥代替石灰石作为冶炼熔剂的可行性,本文研究了石膏污泥中的硫酸钙(CaSO_(4))对铅精矿氧化熔炼的影响。热力学计算表明,硫化矿物与硫酸钙反应生成氧化钙,在高温下氧化钙与氧化亚铁、二氧化硅等结合生成低熔点物质。焙烧试验表明硫化矿物、二氧化硅以及升高温度对硫酸钙转变为氧化钙起促进作用,硫化物矿物对CaSO_(4)转化率的影响强弱顺序为为黄铁矿>闪锌矿>方铅矿。CaSO_(4)和硫化物之间的交互反应促进了CaSO_(4)转化为CaO,这个过程对渣相的形成至关重要。对熔炼条件进行优化后,仅以石膏渣为钙源,在CaO/SiO_(2)质量比为0.8、FeO/SiO_(2)质量比为1.2、熔融温度为1150℃、氧气流量为1.3 L/min的最佳条件下,高铅渣中Pb和Zn的回收率分别达到85.01%和95.69%,硫含量为2.65 wt%,高铅渣经过还原熔炼得到的冶炼渣中As含量为0.02 wt%。石膏污泥在铅冶炼中的资源化利用是可行的方法。

关 键 词：gypsum sludge calcium sulfate resource utilization SMELTING 

分 类 号：X758[环境科学与工程—环境工程] TF812[冶金工程—有色金属冶金]