DOC《富铟锌铁渣中锌和铟的浸出与铁的同步还原（》

富铟锌铁渣中锌和铟的浸出与铁的同步还原( 朱北平1,邓志敢2*,张帆2,魏昶2,李存兄2 (1.

云南华联锌铟股份有限公司,文山 663701;

2. 昆明理工大学 冶金与能源工程学院,昆明 650093) 摘要:我国锌资源储量丰富,其含锌矿物中有很大一部分以高铁闪锌矿的形式存在,并且在这些高铁闪锌矿其中含有丰富的铟资源.为了综合回收高铁闪锌矿湿法炼锌过程富集于中浸渣中的有价金属,开展了中浸渣和锌精矿的还原酸浸实验研究,其主要目的是利用硫酸浸出中性浸出渣中以铁酸盐形式残留的锌和铟,同时利用锌精矿将溶液中的三价铁还原为二价铁,实现锌精矿中锌、铟的同步浸出.考察研究了锌中浸渣和锌精矿的投料质量比、初始硫酸浸出剂浓度、浸出时间、液固比、反应温度、浸出时间对锌、铟浸出率行为的影响,研究表明在初始硫酸浓度220g/L,中浸渣与锌精矿质量比1:0.25,粒度-0.074mm,液固比6mL/g,温度90?C,反应时间3h的条件下,锌、铟的浸出率在96%以上,浸出液中95%以上的铁被还原为二价铁离子,实现了浸出与还原的同步进行. 关键词:铁闪锌矿;

浸出渣;

还原;

浸出;

锌和铟 中图分类号:TF813 文献标识码:A 文章编号: Reducing Ferric and Leaching of Zinc &

Indium from Residue Bearing Indium-Zinc-Ferric Zhu Bei-ping1, Deng Zhi-gan2, Zhang Fan2, Wei Chang2, Li Cun-xiong2 (1. Yunnan Hualian Zinc and Indium Co. Ltd. Wenshan 663701, China;

2.Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China) ABSTRACT: ChinaIt?is?rich?of?zinc?resource, most of which exist in forms of marmatitesphalerite of high iron and highbearing indium in China. In order to recycle the valuable metal rich in neutral leaching residues in the process of zinc hydrometallurgy, the testwork of reduction acid leaching on neutral residue mixed with zinc concentrate with high-iron sphalerite as the research object has been taken in the paper. The primary objectives are to leach the zinc and indium remaining in the neutral leach residue as ferrite, using acid, and to reduce the ferric iron in solution to the ferrous state by reaction with zinc concentrate, thereby extracting the zinc and indium in the zinc concentrate.The effecting factors such as mass ratio of neutral residue and zinc concentrate, initial concentration of sulfuric acid, reaction time, liquid-solid ratio, temperature on leaching efficiency of zinc and indium have been studied in detail and finally obtain the best technical parameters: mass ratio of neutral residue and zinc concentrate 1:0.25, material particle size less?than 0.074mm, initial concentration of sulfuric acid 220g/L, reaction time 3h, liquid-solid ratio 6mL/g, temperature 90℃. The results showed that the leaching efficiency of zinc and indium were over 96%, besides, nearly 95% Fe was Fe2+ in the leaching solution that was suitable for subsequent process under the optimal conditions, which effectively extracts zinc and indium and converted Fe3+ into Fe2+ in solution. KEY WORDS: marmatite;

leaching residue;

reduction;

leaching;

zinc and indium 金属锌已成为是在现代经济建设和国防建设中不可缺少且用量较大的基础战略有色金属.我国拥有储量丰富锌矿物资源,且其在含锌矿物中有很大一部分以富含铟、铜、金、银等有价金属的高铁闪锌矿的形式存在,在富铟高铁闪锌矿常规湿法炼锌工艺过程中锌和铟主要以铁酸盐的形式进入中浸渣[1-3]形成富铟锌铁渣.目前,对此类中浸渣的处理一般是先采用浮选工艺回收其中的部分银[4],再转入采用火法还原挥发工艺利用回转窑或烟化炉挥发处理回收其中的锌、铟、铅、锌、铟、锗等,并同时产出对环境污染较小的含铜含铁的窑固化渣[5].此类工艺对原料适应性较强,铁、硅等可经火法直接分离除去,稀贵金属富集程度高,但稀贵金属回收率低、能耗高、粉尘大、金属损失率大、二氧化硫和铅锌蒸气污染且稀贵金属回收率低,不符合国家的节能、减排、低碳经济政策[6]和行业准入条件,而且伴随能源价格日益上涨,其成本压力越来越大其发展受到一定制约[6].因此,开发高效、清洁、经济适用的适合处理高铁硫化锌精矿的高效、清洁、经济的锌冶炼及资源综合技术技术成为我国锌冶金行业科技创新的重要课题研究方向. 热酸浸出可有效破坏中浸渣中的铁酸锌,实现锌的高效浸出,但当锌的浸出率提高到95%时,铁的浸出率也高达95%以上,并且铁大部分以Fe3+形式存在,需要对溶液进行锌铁分离.目前,从热酸浸出液中分离锌铁的方法主要有黄钾铁矾法、针铁矿法和赤铁矿法[7-9].由于黄钾铁矾渣中含有大量的铅、镉、砷、锌等有害元素,环境污染严重,该除铁方法的应用受到限制,目前大部分锌冶炼企业普遍采用针铁矿法除铁.赤铁矿除铁是实现湿法炼锌锌铁高效分离,清洁生产的重要途径,具有广阔的工业应用前景.但采用针铁矿法或赤铁矿法除铁时,为了回收中浸渣中铟及有利于后续除铁,均须将高铁溶液中的Fe3+还原为Fe2+[10-11]. 为满足后续从热酸浸出的硫酸锌溶液中分离提取铟以及赤铁矿除铁的要求,本文以高铁硫化锌精矿为还原剂,利用锌精矿中的S2-的还原性和中浸渣中Fe3+的氧化性,开展了高铁锌焙砂中浸渣与高铁锌精矿还原浸出实验研究.