回转窑内渣成分优化实现锌铅元素的高效回收（英文）

在回转窑内从高硅锌浸出渣中实现高效回收锌铅金属。XRD、SEM、EDS及ICP表征结果表明，浸出渣含12.4%SiO₂、16.1%Zn和7.4%Pb(质量分数)。热力学分析表明，在回转窑内1150～1250℃的冶炼环境下，锌浸出渣中极易产生锌和铅的金属蒸气。通过分析13种冶金渣成分的黏度及熔点，发现3种渣成分(47%SiO₂-23%CaO-30%FeO、40%SiO₂-28%CaO-32%FeO、40%SiO₂-30%CaO-30%FeO，质量分数)具有合适的物理特性，即熔点和黏度分别为1150～1280℃和0.2～0.5 Pa·s。工业实验表明，采用优化的渣成分，锌和铅的回收率分别高达97.3%和94.5%,冶炼后渣内锌和铅的含量分别低至0.51%和0.45%(质量分数)。水淬渣的国标浸出实验表明，浸出液中含1.82 mg/L Zn、～0.01 mg/L Cu、0.0004 mg/L As、～0.01 mg/L Cd、0.08 mg/L Pb和～0.02 mg/L Hg，证实锌浸出渣同步实现无害化...

Enhanced recovery of zinc and lead by slag composition optimization in rotary kiln

High-efficiency recovery of Zn and Pb from silicon-rich zinc leaching residues is realized in a rotary kiln. Characterizations by means of XRD, SEM, EDS and ICP reveal that the leaching residue contains 12.4 wt.% SiO₂, 16.1 wt.% Zn, and 7.4 wt.% Pb. Thermodynamic analysis shows that metallic vapor of Zn and Pb can be easily generated from the zinc leaching residue at 1150?1250 °C inside the rotary kiln. Viscosities and melting points of 13 slag compositions were analyzed and three slag compositions (47wt.%SiO₂?23wt.%CaO?30wt.%FeO, 40wt.%SiO₂? 28wt.%CaO?32wt.%FeO, and 40wt.%SiO₂?30wt.%CaO?30wt.%FeO) possessed the desirable physical properties, with the melting point and viscosity in the range of 1150?1280 °C and 0.2?0.5 Pa·s, respectively. The industrial tests show that adopting the optimized slag composition can contribute to very high recovery rates of Zn and Pb (97.3% for Zn and 94.5% for Pb), corresponding to slags with very low average contents of Zn and Pb (0.51 wt.% Zn and 0.45 wt.% Pb). The National-Standard leaching tests of the water-quenched slags result in 1.82 mg/L Zn, ~0.01 mg/L Cu, 0.0004 mg/L As, ~0.01 mg/L Cd, 0.08 mg/L Pb, and ~0.02 mg/L Hg in the leachate, verifying the detoxification of the zinc leaching residue at the same time.