内蒙某高温高酸锌浸出冶炼渣中综合回收银的研究

发布时间：2018-02-26 19:42

本文关键词： 高温高酸锌浸出渣渣物质组成快速浮选六偏磷酸钠分散机理　出处：《江西理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：目前,从湿法冶炼渣中回收银已经成为银生产的一条重要途径。常规法锌浸出渣中的银基本可以通过浮选法得到有效回收,并实现了工业化生产。随着湿法炼锌的技术发展,高温高酸浸出法大大提高了锌的浸出率和其他有价金属的浸出率,但银却进一步的富集在渣中而没有得到回收。本次试样取自内蒙某公司锌冶炼厂,该厂采用高温高酸工艺浸出锌,试样为锌浸出渣。本文对该浸出渣的物质组成做了详细的研究。该浸出渣中可溶性物质主要为水锌矾,不可溶性物质主要是水铁矾Fe[SO4]?H2O,其次为硅胶体和含锌(铅)氧化铁,并残余一些矿物碎屑(赤铁矿、锌铁尖晶石、长石、石英等)。该浸出渣含银240g/t左右(除去渣中40.96%水溶物后含银400g/t左右)。利用MLA进行矿物自动检测系统及矿物多元素能谱分析可知,该浸出渣中主要的银矿物有氯角银矿、螺状硫化银矿、硫铜银矿,其他银呈零星点状分布于浸出渣中一些矿物的表面,其中部分存在于黝铜矿、铜蓝、黄铜矿等铜矿物和闪锌矿、铅硬锰矿表面,含锌氧化铁、硅胶等氧化矿或是硅酸盐矿物表面也分布着微细粒银。银主要与锰矿物、铜矿物和闪锌矿相关。根据浸出渣的物质组成及银赋存状态的研究结果,确定合理的浮选工艺,通过单因素条件试验及开路流程优化试验,最终确定了最佳的浮选工艺流程。采用“一快速浮选一粗二精二扫”的闭路工艺流程,可获得含银3087g/t,回收率5.67%的银精矿1和含银2186g/t,回收率61.23%的银精矿2。综合精矿银品位为2 242g/t,回收率66.9%,回收了该渣中的银矿物。机理研究表明,六偏磷酸钠是由多个(20~100)PO3-单元聚合而成的长链状聚磷酸盐,其在水中可电离出电负性较强的,能与所有金属阳离子络合形成稳定络合物;矿浆中加入六偏磷酸钠之后,在粒子之间距离为2~4nm时出现较大的势垒,粒子相互靠近时存在较大的斥力,随着粒子间距离增大,斥力减小,矿浆处于分散状稳定状态。
[Abstract]:At present, the recovery of silver from hydrometallurgical slag has become an important way of silver production. Silver from zinc leaching slag by conventional method can be recovered effectively by flotation, and industrial production has been realized. With the development of zinc hydrometallurgy technology, The leaching rate of zinc and other valuable metals was greatly improved by acid leaching at high temperature and high temperature, but silver was further enriched in the slag and not recovered. The sample was taken from a zinc smelter in Inner Mongolia. Zinc was leached by high temperature and high acid process, and the sample was zinc leaching slag. In this paper, the composition of the leaching slag was studied in detail. The soluble substance in the leaching slag was mainly zincosite, and the insoluble substance was mainly SO4? H2O, followed by silica gel and zinc (lead) ferric oxide, and residual mineral clasts (hematite, zinc-iron spinel, feldspar, etc.). The leaching slag contains about 240 g / t silver (about 400 g / t of silver after removing 40.96% water solutes from the residue). The main silver minerals in the leaching slag are chloriferite, which is determined by MLA automatic mineral detection system and multielement energy spectrum analysis. A sphalerite containing zinc oxide on the surface of some minerals in leachate, such as tetrahedrite, copper blue, chalcopyrite, and sphalerite. Fine silver is also distributed on the surface of oxidized ores such as silica gel or silicate minerals. Silver is mainly related to manganese, copper and sphalerite. According to the results of the study on the composition of leaching slag and the state of occurrence of silver, a reasonable flotation process is determined. Through the single factor condition test and the open circuit flow optimization test, the best flotation process was finally determined. The closed-circuit technological process of "one quick flotation, one coarse, two fine and two sweep" was adopted. Silver concentrate with silver content of 3087 g / t, silver concentrate with recovery rate of 5.67% and silver concentrate with silver recovery of 61.23% and silver concentrate with recovery of 5.67% g / t and 61.23% respectively were obtained. The silver grade of comprehensive concentrate was 2242 g / t and recovery rate was 66.9%. Silver minerals in the slag were recovered. Sodium hexametaphosphate is a kind of long chain polyphosphate which is formed by the unit polymerization of a number of 20 ~ (20) O _ (100) O _ (3-). It can ionize out electronegativity and form a stable complex with all metal cationic ions, and when sodium hexametaphosphate is added to the pulp, the sodium hexametaphosphate can be ionized into the water to form a stable complex. When the distance between particles is 2 ~ 4 nm, there is a larger barrier and a large repulsion force when the particles are close to each other. With the increase of the distance between particles, the repulsion force decreases, and the slurry is in a dispersive state.
【学位授予单位】：江西理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD923;X758

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