稀土冶炼过程草酸沉淀废水资源化处理技术
Recycling of oxalic acid precipitation wastewater from hydrometallurgy process of rare earth

杨帆晏波 ^* 权胜祥李宁张乐

文摘	为了实现稀土生产草沉废水的资源回用,对稀土草酸沉淀废水建立资源回收工艺,回收废水中的草酸和盐酸。研究包括草沉废水水质分析、草沉废水蒸馏分离工艺研究、蒸馏盐酸的回收利用、盐酸蒸发过程中的浓度变化趋势分析、草沉废水草酸回收研究以及工艺经济性分析。结果表明:草沉母液中TOC含量为4 661 mg/L,金属离子总体含量不高;通过常压实沸点蒸馏发现,草沉母液可回收5 mol/L盐酸330 mL/L或1 mol/L盐酸600 mL;蒸发后草酸产率超过16 g/L草沉废水;并且结晶草酸纯度≥99.5%,硫酸根未检出,灼烧残渣≤0.16%,重金属(以Pb计)≤0.000 01%,铁离子≤0.004 5%,氯化物≤0.08%。通过上述研究,为草沉废水资源化处理技术的工业化应用提供了理论依据。
其他语种文摘	The recycling technology of rare earth wastewater from deposited oxalic acid (REWOA) was investigated in this paper. First, the total organic carbon (TOC) content and metal concentrations of REWOA were tested. Second, the atmospheric pressure boiling point distillation of REWOA was studied. Lastly, the oxalic acid (OA) crystal and hydrochloric acid (HCl) from the distillation were evaluated. The results showed that the metal ion contents of REWOA were relatively low. The TOC of REWOA was 4661 mg/L. Following distillation, the recovery rate of 5 mol/L HCl was almost 330 mL/L. The HCl of 1 mol/L could reach 600 mL/L. Oxalate crystal productivity was 16 g/L REWOA. The purity, sulfate (SO_4~(2-)) content, incinerated residue content, heavy metal (Pb) content, iron (Fe) ion content, and chlorine (Cl~-) of oxalic acid crystal were ≥99.5%, undetectable, ≤0.16%, ≤0.000 01%, ≤0.004 5%, and ≤0.08%, respectively. These results could provide a theoretical basis for an industrial application.
来源	环境工程学报 ,2016,10(4):1789-1793 【核心库】
关键词	稀土冶炼废水 ; 草酸 ; 盐酸 ; 资源回收
地址	中国科学院广州地球化学研究所, 广州, 510640
语种	中文
文献类型	研究性论文
ISSN	1673-9108
学科	行业污染、废物处理与综合利用
基金	广东省科技计划项目 ; 广东省省级环保专项资金项目
文献收藏号	CSCD:5676645