负压蒸馏法含铁废盐酸资源化实验研究

发布时间：2018-07-02 20:44

  本文选题：含铁废盐酸 + 负压蒸馏　； 参考：《安徽工业大学》2015年硕士论文

【摘要】：钢材酸洗废液中含有大量的铁离子和游离酸,直接排放不仅造成严重的环境污染问题,而且造成大量资源的浪费。高温焙烧法主要适用于大型企业,而中小型企业目前主要采用传统法—中和沉淀法或者委托具有危废处理资质的单位进行处理,废酸传统的处理法存在污泥处理困难以及资源浪费等问题。本课题研究了“负压蒸馏+湿法制备氧化铁红”的组合工艺,对含铁盐酸酸洗废液进行综合处理利用,以期为工业化应用提供指导。该工艺包括以下几个阶段:首先对废酸进行负压蒸馏操作,氯化氢气体经过冷凝后得到再生盐酸;蒸馏母液进行结晶,配制一定浓度的亚铁溶液,采用湿法合成FeCO3沉淀,然后进行干燥、煅烧制备氧化铁红颜料。针对该工艺,本文进行了以下几个方面的研究。本文首先自行设计负压蒸馏处理装置,考察真空度、温度、时间三种因素对盐酸回收率以及再生酸浓度的影响,实验结果表明:在真空度为0.075 MPa、温度为76℃、反应时间为55 min的条件下,盐酸回收率达到最高约为84.3%,再生酸的浓度约为0.89 mol/L,颜色为无色。本文选择两种中和沉淀剂合成FeCO3沉淀,通过单因素、正交试验进行对比,实验结果表明:最佳工艺条件为NH4+/Fe2+摩尔比(n/n)为2.6,碳酸氢铵/碳酸铵摩尔比(n/n)为5:4,水浴温度为50℃,反应时间为60 min,振荡转速为120r/min,铁红的纯度达到99%左右;干燥实验结果表明:在干燥温度为80℃,干燥时间为3 h的条件下,煅烧产物颜色为红棕色;煅烧实验结果表明:在煅烧温度700℃、煅烧时间1 h的条件下铁红的纯度约为98.84%;通过XRD、FI-TR、EBSD表征,煅烧的最终产物为2 3??Fe O,晶粒粒径分布均匀,为多孔型球状晶体;通过对自制产品颜料性能的测试,其纯度符合GB/T1863-2008中的颜料红101中的A类标准,其它性能基本上满足标准中的Ⅰ型或a类标准。该工艺实现了含铁盐酸酸洗废液资源化的综合利用,既解决了废酸对环境的污染问题,又为铁红颜料的生产提供了新的原料和工艺,具有良好的经济效益和社会环境效益。
[Abstract]:There are a lot of iron ions and free acids in the waste liquor of steel pickling. The direct discharge not only causes serious environmental pollution but also waste a lot of resources. The high-temperature roasting method is mainly suitable for large enterprises, while the small and medium-sized enterprises mainly adopt the traditional method-neutralization precipitation method or entrust the units with the qualification for the treatment of dangerous wastes to deal with it at present. The traditional treatment of waste acid has the problems of sludge treatment and waste of resources. In this paper, the combined technology of "negative pressure distillation wet method to prepare iron oxide red" was studied, and the comprehensive treatment and utilization of acid pickling liquid containing iron hydrochloric acid were carried out in order to provide guidance for industrial application. The process includes the following stages: first, the waste acid is distilled under negative pressure, the hydrogen chloride gas is condensed to regenerate hydrochloric acid, the mother liquor of distillation is crystallized, and a certain concentration of ferrous solution is prepared, and the precipitation of FeCO3 is synthesized by wet method. Then drying and calcining to prepare iron oxide red pigment. In view of this process, this article has carried on the following several aspects research. In this paper, a vacuum distillation unit was designed to investigate the effects of vacuum, temperature and time on the recovery rate of hydrochloric acid and the concentration of regenerated acid. The experimental results show that the vacuum degree is 0.075 MPA and the temperature is 76 鈩，

本文编号：2090864