富铟锌浸渣热酸浸出锌铟的研究

以富含铟的湿法炼锌中性浸出渣为研究对象,研究了热酸浸出过程中锌、铟等有价金属的溶解行为。结果表明,随着锌浸渣的溶解,浸出液中Fe3+浓度及氧化还原电位不断升高,抑制了铁酸锌的溶解,在第一、二段浸出条件分别为:反应温度90℃、液固比10∶1、浸出时间4 h;初始硫酸浓度160 g/L、反应温度90℃、液固比10 m L/g、浸出时间4 h的试验条件下,采用两段逆流浸出工艺处理该渣,锌、铟的浸出率分别为96.53%、94.85%。     

利用含锌工业固废制备高纯氧化锌的工艺研究

针对氧化锌尾矿和废弃水渣等工业固废中有价锌难以回收的问题,以当地工业含锌固废为原料,利用碳热还原氧化法,制备了高纯氧化锌微粉。通过HSC Chemistry进行热力学计算和试验研究结合的方式,分析了含锌废渣中硅酸锌与碳还原反应的热力学过程。讨论了配碳量、焙烧温度、焙烧时间以及CaF₂对硅酸锌还原过程锌产率的影响。结果表明,在以CaF₂为催化剂时,1 000～1 100℃催化效果最显著。得出最佳工艺条件：在温度为1 100℃、保温时间40 min、碳含量20 wt%、CaF₂添加5 wt%的条件下锌产率(氧化锌回收率)为97.44%。对挥发产物进行结构和成分分析,其物相为六方纤锌矿结构的氧化锌晶体,粒度大小2～4μm,纯度达到了99.47%。     

常压富氧浸出含锗氧化锌烟尘回收锌和锗

针对湿法炼锌过程中稀散金属锗的浸出,以含锗氧化锌烟尘为原料,采用常压富氧浸出技术从含锗氧化锌烟尘中回收锌和锗。氧化锌烟尘的X射线衍射(XRD)和扫描电子显微镜-能谱分析(SEM-EDS)等分析结果表明,富锗氧化锌烟尘除含有氧化锌外,还含有少量硫化锌与硫化铅,部分硫化锌与氧化锌混合形成致密颗粒。考察了铜离子浓度、时间、液固比、温度、氧压等因素对氧化锌烟尘浸出锌、锗的影响。结果表明,在常压富氧条件下,温度90℃、液固比7mL/g时,采用两段浸出4h,锌、锗的浸出率可超过90%;浸出渣主要物相为硫酸铅和硫化锌。采用氧化锌烟尘做中和剂对酸浸溶液进行中和还原处理,控制溶液pH值为3～3.5,反应时间1h,可将溶液中Fe3+的浓度控制在0.02g/L内,且该过程溶液中的锗不发生水解损失,有利于后续溶液中锗的高效分离回收。     

酸浸法从低品位氧化锌矿及含锌废石制备碱式碳酸锌

采用酸浸法从新疆紫金低品位氧化锌矿及含锌废石制备碱式碳酸锌。在磨矿细度为-74μm占30%,液固比2,硫酸用量52kg/t矿,浸出时间2h,终点pH 1.5~2.0,锌浸出率为63%,氧化锌浸出率97%左右;浸出液采用碳酸钙预中和—碳酸钠沉锌工艺回收锌,在预中和终点pH 4.5~5.0、碳酸钠沉锌终点pH 8.0左右,最终获得锌沉淀率为99%,锌品位约50%的碱式碳酸锌产品,该产品可作为生产电锌的原料。     

Recovery of zinc from an industrial zinc leach residue by solvent extraction using D2EHPA

A hydrometallurgical treatment involving solvent extraction of zinc using di-2-ethylhexyl phosphoric acid (D2EHPA) has been investigated to recover zinc from an industrial leach residue. The residue was leached with sulfuric acid producing leach liquor which was subjected to solvent extraction for enrichment of zinc and removal of impurities. Operating variables, such as pH, D2EHPA concentration, temperature, aqueous/organic (A/O) phase ratio, tri-butyl phosphate (TBP) concentration and sodium sulfate (Na₂SO₄) concentration in aqueous phase were studied. Practically, all zinc was extracted from the aqueous solution at pH 2.5 with 20% w/w D2EHPA in kerosene. Increasing either TBP concentration up to 5%, or Na₂SO₄ concentration up to 0.2 M, increased the zinc extraction. Zinc could be extracted at one theoretical stage at A/O of 1/1, as calculated by McCabe–Thiele method.     

Mass transfer correlation of removal of nickel by cementation onto rotating zinc disc in industrial zinc sulfate solutions

A rotating zinc disc was used to study the cementation of nickel from an industrial acidic solution of zinc sulfate. The reduction of nickel was evaluated for a wide concentration range of initial nickel concentration, electrode rotation speed and temperature. The rate of cementation giving the product ka_e of the local mass transfer coefficient k and the effective surface area a_e was analyzed and expressed in terms of the rate of mass transfer versus the apparent mass transfer coefficient and correlated by a controlling numbers relationship.An estimation, by two methods, of the surface roughness variation caused by the nickel deposit was presented.     

从锌浸出渣中强化浸出锌锗的试验研究

针对云南某湿法炼锌浸出渣,采用硫酸强化浸出对渣中锌、锗、铁的浸出效果进行研究。正交试验结果表明:最优浸出条件为:溶出温度160℃,硫酸浓度为1.5 mol/L,浸出时间1.5 h,液固比为6。最优浸出条件下,锌和锗的平均浸出率分别高达96.77%和70.86%,有害元素铁的平均浸出率仅为55.44%,在抑制铁浸出的同时,保证了锌锗元素的高效浸出。     

Copper leaching from waste electric cables by biohydrometallurgy

This study examines the leaching of copper from waste electric cables by chemical leaching and leaching catalysed by Acidithiobacillus ferrooxidans in terms of leaching kinetics and reagents consumption. Operational parameters such as the nature of the oxidant (Fe³⁺, O₂), the initial ferric iron concentration (0–10 g/L) and the temperature (21–50 °C) were identified to have an important influence on the degree of copper solubilisation. At optimal process conditions, copper extraction above 90% was achieved in both leaching systems, with a leaching duration of 1 day. The bacterial leaching system slightly outperformed the chemical one but the positive effect of regeneration of Fe³⁺ was limited. It appears that the Fe²⁺ bio-oxidation is not sufficiently optimised. Best results in terms of copper solubilisation kinetics were obtained for the abiotic test at 50 °C and for the biotic test at 35 °C. Moreover, the study showed that in same operating conditions, a lower acid consumption was recorded for the biotic test than for the abiotic test.     

湿法炼锌中性浸出液分步除铜镉净化新工艺

针对湿法炼锌净化工艺存在效率低、锌粉单耗高、成本高的问题,以锌粉为置换剂,采用分步除铜镉工艺去除湿法炼锌中性浸出液中的铜和镉。在除铜工序,研究了锌粉用量、反应时间、反应温度及搅拌强度等工艺参数对除铜的影响。在深度除镉工序,研究了除镉剂用量、除镉时间、除镉温度及搅拌强度等因素对除镉的影响。结果表明,在优化条件下,中性浸出液经一段除铜镉后,溶液中铜含量小于0.01mg/L、镉含量21.38mg/L,达到了一段除铜镉的技术控制指标,并且显著减少了一段净化的锌粉消耗量,以10万t/a湿法炼锌系统为例,年可节约成本约1 980万元。     

锌中浸渣中锌和铟的SO_2还原浸出研究

目前湿法炼锌过程中的锌浸出渣处理工艺存在着有价金属回收率低、工艺技术指标差等问题。针对这些不足,开展了锌中性浸出渣的SO_2还原浸出研究。研究结果表明,与热酸浸出相比,采用SO_2还原浸出工艺能够显著提高原料中锌、铟的浸出率。用SO_2作还原剂,研究了温度,初始酸浓度,SO_2压力对中浸渣中锌、铟的浸出率的影响。在硫酸浓度为100g/L,反应温度110℃,液固比10∶1,时间120min,SO_2分压0.3MPa的浸出条件下,锌、铟的浸出率最高,分别为93.8%、92.3%。     

锌焙砂浸出制备铁酸锌研究

本文以含锌53.35%、含铁13.51%及铁酸锌13.97%的锌焙砂为原料,在对锌焙砂粒度分析、X-荧光多元素半定量分析、XRD分析及锌铁物相分析基础上,采用硫酸做浸出剂,研究始酸浓度、液固比、搅拌速度、浸出温度、浸出时间等因素对浸出渣物性的影响。结果表明,获取高含量ZnFe_2O_4浸出产品的试验条件为:始酸浓度100 g/L、液固比8∶1、搅拌速度400 r/min、浸出温度75℃、浸出时间120 min。     

工业废盐酸浸出拜耳赤泥中铁、铝的试验研究

研究了工业副产废盐酸常压浸出拜耳法赤泥中铝、铁的过程。考察了盐酸浓度、浸出温度、浸出时间和液固比对氧化铁、氧化铝浸出率的影响。通过试验得出了较佳浸出工艺条件:盐酸浓度25%、酸浸温度90℃、酸浸时间60 min、液固比6∶1。在此条件下,铁的浸出率为92.51%,铝的浸出率为90.12%。各因素对氧化铝氧化铁浸出率影响大小为:酸浸反应温度盐酸浓度反应时间液固比。同时,利用硫酸铁作为除钙剂对赤泥盐酸浸出液进行脱钙处理,Ca~(2+)一次脱除率达83.3%。研究成果为低浓度工业废盐酸和贵州拜耳赤泥的处置与利用提供了理论依据和技术参考。     

加压氧化—氰化浸出法从氰化尾渣中回收金

山东某金矿为高硫多金属矿床，矿石中的伴生元素为Ag、Fe、Cu、Pb、Zn、S等元素，该矿采用浮选法将矿石中的金富集，生产的金精矿再磨后直接氰化浸出。生产实践表明，在氰化尾渣中金的品位高达3～4g／t，这不但浪费了国家资源，还影响了企业经济效益的提高。本文运用加压氧化-氰化浸金的原理，采用一种加压氧化-氰化浸金设备，对氰化尾渣进行了加压氧化-氰化浸金工艺试验。     

难处理复杂氧化锌烟尘碱洗渣浸出试验研究

对铅冶炼难处理复杂氧化锌烟尘碱洗渣进行了"中性浸出—酸浸"工艺试验研究。结果表明,碱洗渣中性浸出时,锌、镉的浸出率先随浸出温度、液固比、搅拌速度和时间的增加而提高,后增速变缓;中浸渣酸浸时,液固比对锌、铟的浸出率无明显影响。锌、铟的浸出率随初始酸度、浸出温度和时间的增加先增加后变缓。中性浸出最佳条件为:温度338K、液固比5∶1、搅拌速度400r/min、浸出时间1h,此条件下,锌、镉的浸出率分别为80.3%和76.3%。中浸渣酸浸最佳条件为:初始酸度100g/L、浸出时间2h、浸出温度363K、液固比5∶1,在该条件下,锌、铟的浸出率分别为97.1%和85.5%。     

低品位氧化锌矿硫化转化—浮选工艺回收铅锌

以云南某地区的砂岩和灰岩按1.5∶1配成的混合矿为研究对象,分别考察无硫化混合矿样和在固定硫化时间180min、矿物粒度-0.074mm占87%以上、液固比1.2∶1、硫磺量为原料量的5.5%的条件下,硫化转化温度分别为155、165、175、185、195、215、225℃时所得硫化产物的浮选效果。结果表明,硫化产物比无硫化的氧化锌矿的浮选效果好;无硫化的氧化锌矿直接浮选时,铅、锌的回收率分别为33.58%、35.77%,而当硫化转化温度为225℃时,铅、锌的回收率较高,分别为95.77%、93.52%。     

铅冰铜氧压浸出铜锌试验研究

为有效回收铅冰铜和烟灰中的铜铅锌资源,采用浮选试验和硫酸氧压浸出方法,探讨了回收铜、锌的可行性。研究表明:浮选分离铅冰铜中铜铅较为困难,而铅冰铜单独氧压浸出和铅冰铜与烟灰混合浸出均能取得较好的铜锌浸出效果,且混合处理指标更优。适宜条件下,铅冰铜单独浸出时,铜、锌浸出率达到88.25%和95.46%;铅冰铜与烟灰混合浸出时,铜、锌浸出率达到94.40%和99.65%。浸出液多次循环浸出,铜锌浸出率都能维持在83%以上,浸出液循环后溶液中铜锌浓度能满足后续工序要求。     

锌中浸渣-硫化锌精矿协同浸出锌、铟的研究

本文在硫酸体系下对锌中浸渣-硫化锌锌精矿协同浸出工艺与锌中浸渣直接热酸浸出工艺进行了对比。实验结果表面：添加锌精矿进行协同浸出能够有效提高锌中浸渣中有价金属锌、铟和铁的浸出率。在实验的基础上,对锌中浸渣-锌精矿协同浸出机理进行了探讨,为协同浸出提供了理论依据。     

从焙烧氰化尾渣中回收金、银

对于含铜、砷金精矿,国内外黄金冶炼厂通常采用焙烧氰化法提取金、银,但所产的氰渣中金、银的含量较高,其品位分别为Au1.5～2.5g/t、Ag150～250g/t.如何从焙烧氰化尾渣中回收Au、Ag,合理地利用矿产资源,提高企业的经济效益,是目前黄金选冶工艺中急待解决的难题.为此,我们以山东招远黄金冶炼厂焙烧氰化尾渣为原料进行了试验研究.结果表明,采用添加剂进行尾渣焙烧-氰化浸出的工艺,金、银的回收率分别达到61.54%和76.81%.该方法投资少、成本低、简单易行,具有较好的经济效益和社会效益,值得推广应用.     

A novel method to recover zinc and iron from zinc leaching residue

A novel method to recover zinc and iron from zinc leaching residue (ZLR) by the combination of reduction roasting, acid leaching and magnetic separation was proposed. Zinc ferrite in the ZLR was selectively transformed to ZnO and Fe₃O₄ under CO, CO₂ and Ar atmosphere. Subsequently, acid leaching was carried out to dissolve zinc from reduced ZLR while iron was left in the residue and recovered by magnetic separation. The mineralogical changes of ZLR during the processes were characterized by XRF, TG, XRD, SEM–EDS and VSM. The effects of roasting and leaching conditions were investigated with the optimum conditions obtained as follows: roasted at 750 °C for 90 min with 8% CO and CO/CO + CO₂ ratio at 30%; leached at 35 °C for 60 min with 90 g/l sulfuric acid and liquid to solid ratio at 10:1. The iron was recovered by magnetic separation with magnetic intensity at 1160 G for 20 min. Under the optimum operation, 61.38% of zinc was recovered and 80.9% of iron recovery was achieved. This novel method not only realized the simultaneous recovery of zinc and iron but also solved the environmental problem caused by the storage of massive ZLR.