Abstract:

The radioactive metal ions in wastewater with low-level radioactivity are hydrolysable in solution. The simulated wastewater containing nuclear ions,such as Fe³⁺,Co²⁺,Mn²⁺and Ni²⁺ has been treated. By regulating the pH,promoting the hydrolyzation of metal ions and combining with ultrafiltration technique,the relationship of hydrolysis constant Kh1 and removal rate and the effect of pH on removal rate are discussed and studied. The research results show that the removal efficiencies of Fe³⁺,Co²⁺,Mn²⁺,Ni²⁺ are up to 95% when the pH of the four solutions are 3.7,9.5,9.2 and 9.0 respectively. This indicates that this method can remove metal ions effectively. At the same time,the mechanism of membrane fouling is discussed as well. By means of comparison,the superiority of ultrafiltration process and neutralization/condensation/precipitation process is analyzed.

Key words: hydrolyzation, ultrafiltration, removal rate, neutralization/condensation/precipitation

摘要：

低放废水中的放射性金属离子在溶液中存在水解现象,以模拟废水中常规核素离子Fe³⁺、Co²⁺、Mn²⁺、Ni²⁺为处理对象,通过适当调节pH,促进金属离子水解,结合超滤技术,对水解常数Kh1与截留率的关系、pH对截留率的影响进行了讨论和研究。研究发现,在pH分别为3.7、9.5、9.2、9.0时,Fe³⁺、Co²⁺、Mn²⁺、Ni²⁺的截留率均可达到95%,能较好地去除金属离子。同时对膜污染的机理进行了探讨,通过对比,分析了超滤法较中和凝聚沉淀法的优势。

关键词: 水解, 超滤, 截留率, 中和凝聚沉淀

CLC Number: 

• TL353+.5

• X703.1