【作者】 张寒霜；

【导师】 黄松涛；

【作者基本信息】 北京有色金属研究总院 ， 有色金属冶金， 2011， 硕士

【摘要】 随着中国经济持续增长,中国建筑业、汽车工业和空调制造业的需求强劲,导致锌的需求大幅增长,而锌矿产资源日趋贫乏且朝贫、细、杂的方向发展以及环保压力的增加,对再生锌的循环利用逐步成为支持锌资源可持续发展的重要手段,而废镀锌板炼钢粉尘中含有大量的锌,因而废镀锌板炼钢粉尘的综合回收利用研究已成为一项重要的课题。本文针对苏州钢厂废镀锌板炼钢粉尘中锌主要以氧化锌和铁酸锌形式存在的特点,从热力学、动力学方面的分析,探索了氧化锌和铁酸锌的浸出机理,在此理论基础上进行了二段浸出、除铁、萃取的试验研究。论文的主要研究成果和内容如下：1、常温稀酸浸出,针对粉尘中锌主要以氧化锌形式存在的浸出行为的研究。试验最佳条件为：反应时间1h,液固比为4,硫酸浓度为60g/L2、高温强酸浸出,针对粉尘中锌主要以铁酸锌形式存在的浸出行为的研究。试验采用粉尘常温稀酸浸出渣为原料,反应时间、反应温度、硫酸浓度、液固比等因素均影响铁酸锌的浸出率。提高反应温度和增加硫酸浓度,在较短时间内即可使锌的浸出率达到90%以上。控制浸出温度为90℃,浸出时间为2h,液固比为8,硫酸浓度为180g/L,为常温浸出渣高温强酸浸出的最佳条件。3、浸出过程中,粉尘中的铁也大量进入浸出液,为满足锌电积的要求,必须进行除铁试验研究。试验结果表明,黄铁矾法、针铁矿法、磷酸盐法三种沉淀除铁均能实现锌、铁的有效分离,其中,磷酸盐沉铁法除铁速度最快,效果最好。4、萃取过程中,采用经皂化后P204钠盐作为锌萃取剂,从浸出液中萃取锌,锌的萃取率可达到99.9%以上5、反萃过程中,采用硫酸作为反萃剂的锌溶剂,负载有机相中的锌离子可彻底被反萃,铁离子难被反萃,可实现锌铁分离。经1级萃取后,可将锌离子浓度从11.89g/L富集到70g/L6、浸出过程热力学表明,废镀锌板炼钢粉尘的酸浸过程属放热反应,反应平衡常数很大,且随着温度升高而下降；动力学过程研究表明其酸浸过程为收缩未反应核模型,浸出反应属于界面化学反应步骤控制；反应级数大于1,提高酸度可促进浸出过程。更多还原

【Abstract】 With the rapid development of national economy, our country needed more zinc used in construction industry, automotive industry and air-conditioning manufact.Meanwhile, the mineral become poor, small and complex.With the pressure of environmental protection,the synthetical utilization of dust from electric arc furnace useless galvanized steel has increasingly become an urgent issue.The dust from electric arc furnace useless galvanized steel of Suzhou steelworks was studied in this paper. Including the analysis of thermodynamics and kinetics and seeking for leaching mechanism. And then, carry out the experiment about leaching, deferrization, extraction. The results and conclusion were as follows:1、Leaching the dust by dilute acid at normal temperature. It can be leach zinc oxide in the dust. The optimum leaching condition is that:leaching time 1h, L/S 4, sulfuric acid concentration 60g/L.2、Leaching the residue from dilute acid by high concentraded acid at high temperature. It can be leach zinc ferrite in the residue. The residue contain zinc ferrite is 96.74%. The optimum leaching condition is that:leaching time 4h, temperature 90℃, L/S 8, sulfuric acid concentration 180g/L.The leaching rate could come up to 90% by improving temperature and acid concentration, simultaneity, the impurity also coming into lixivium3、During leaching process, most of the iron in the dust was dissolved into solution. Thus, in order to meet the requirements of zinc electrowinning, iron ion was rejected from the leaching solution. Experimental results show that jarosite process, goethite process and phosphate process all can remove iron ion from solution bearing zinc ion; the precipitation rate of iron ion by phosphate process is the fastest of all three processes and phosphate process is the best process of the effect of precipitation iron in three processes.4、P204 was saponified which was used as the extractant of zinc.The extraction yield of zinc from leaching solution could reach 99.9% under favorable conditions.5、In zinc stripping process, sulfuric acid was used as an agent of zinc extractant. The zinc ion in the organic phase load could be extracted thoroughly, however, iron ion in the organic phase load was hardly extracted by sulfuric acid ion.After one step stripping, the concentration of zinc iron was raised from 11.39g/L to 70g/L. 6、The thermodynamic of leaching process shows that acid leaching process of waste galvanized steelmaking dust is a exothermic reaction; the reaction equilibrium constant is big and it is decreased with the increasing of temperature. Dynamic process research shows that its acid leaching process is the contraction not reaction nuclear model;the leaching reaction belongs to chemical reaction steps control;the reaction order is over one, the leaching rate of zinc is enhanced with the increasing of acid concentration.更多还原