【作者】 邵琼；

【导师】 兰尧中；

【作者基本信息】 云南师范大学 ， 物理化学， 2004， 硕士

【摘要】 二次资源的回收再利用是当今世界环保的一大主题。铜镉渣是湿法炼锌过程产生的副产品，量大(每吨电锌副产出该废渣大约100公斤)，是一种宝贵的二次资源。该渣一般含Cd5％-10％、Cu1.5％—5％、Zn28％—50％。 本论文归纳了电锌副产品—铜镉渣的国内外利用现状。针对云铜集团昆明锌厂铜镉渣中锌含量低(15.92％)、镉含量高(25.04％)的特点，提出了一种新的处理工艺流程。 低锌高镉渣的浸出受酸度、液固比、反应温度、浸出时间等诸多因素的影响。实验中首先通过对影响浸出各因素的实验研究，确定最优化综合浸出条件为酸度10％，反应温度80℃，液固比为1：5，反应时间为300min，此时综合浸出率可达89％。 通过对影响置换各因素的研究，确定最优化置换工艺为反应温度40-50℃，反应时间为1h，锌粉的用量为理论用量的150％。结合以上三个条件，此时置换液中铜的置换率＞99.99％，镉的置换率为99.98％，故可认为被完全置换。 浸出液中的杂质无论从种类上还是含量上都较多，故需除去，以免影响产品质量。本文通过对除杂质时各个影响因素的探讨，以及除铁方法的比较，进而发现用过硫酸铵除去低锌高镉渣酸浸液中的铁、锰效果较好。其最佳工艺条件为：温度90℃，PH值为1.5-2，反应时间3h。再调节PH值=4.0-4.5，让其沉淀完全，此时，除铁率可达云南师范大学硕士学位论文90%以上，酸浸液中的Fe含量可降至0.019几，锰含量<0.069几。 本文还研究了低锌高福渣的浸出化学反应动力学模型及机理。从动力学的角度分析整个浸出流程，由实验数据建立了符合扩散控制的动力学模型卜粤。一(l一。声一欠;，并通过Arrhenin，经验公式，由一系 3’歹d不同温度时的In瓦值对上作图，求得反应活化能为8.193kJ/mol。该 T浸出过程受固膜扩散控制，通过含锌废渣固相膜层的扩散速率是整个浸出反应的控制速率。 最后本论文根据国内外化工产品需求情况，对符合市场需要的、高附加值的锌、福的系列精细化工产品的发展趋势进行了展望，为下一阶段的研究工作奠定了基础。更多还原

【Abstract】 The recovery and reutilization of the solid waste is the most interesting issue of the environmental protection nowadays. According to the present condition of the mass slag, which is produced from the factory of smelting zinc hydrometallurgically and has not handled because of the limit of the fund and technology. With the ever-depleting supply of valuable elements, the task of comprehensively recovering them from the slag becomes significant. It is very important not only in the reutilization of resources and environmental protection, but also in the economic effect of the enterprise.Based on the present situation of recovery and reutilization of the low-grade Zn with high-grade Cd slag, laboratorial-scale experiments about new technology have been studied systematically in this paper. The slag used in the experiment contains 15.92%Zn, 25.04%Cd, 12.18%Cu, 0.34%Fe, 0.29%Mn. The purpose of the present study is to make use of these characteristics to probe a new hydrometallurgical approach to recover and utilize multiple elements in copper-bearing cadmium slag.A study on the reaction kinetics of leaching slag comprehensively was carried out. The effects of acidity, solid/liquid ratio, reaction temperature, leaching time on the comprehensive leaching rate were determined. According to experiment, the optimum conditions obtained are as follows: acidity=10%, temperature=80 , S/L ratio=l:5, time=300min. Under the optimum conditions, the comprehensive leaching rate is more than 89%. The leaching reaction is a typicaloxido-reduction, and the results show that the leaching process can be simulated with a shrinking core model. The comprehensive leaching rate is controlled by the diffusion of reacting reagents in a porous solid layer.An empirical equation for the leaching reaction kinetics is established,which expressed by the equation of . It provides thetheoretical basis for the process of leaching low-grade Zn bearing high-grade Cd slag with high performance and low consumption. The activation energy calculated according to the Arrhenius equation is 8.193 kJ/mol.Several current processes of cementating Cd and Cu, and removing Fe and Mn ion in leaching solution are described in this paper. The effects of PH value of leaching solution, reaction temperature and time, zinc powder, the stirring speed, and others on the cementation or remove rate is analyzed and discussed in detail in this one. Under the optimum conditions, the Cd-cementation rate is more than 99.98%, the Cu- cementation rate is above 99.99%, and the Fe-removal rate is more than 90%.According to the gradual finization of current zinc and cadmium product, this paper is focused on the trend of the zinc and cadmium fine chemical engineering product with high additional worth. It puts one’s figure on the orientation of the next stage.更多还原