UF-RO膜组合工艺处理低放射性废水方法研究

Study on Treating of Low-Level Radioactive Reactor Wastewater by Combined Membrane Process(UF-RO)

根据高通量工程试验堆产生的低放废水中离子核素的特点,采用新型膜组合工艺分离技术进行高效处理试验堆低放射性废水的研究。通过配制含有Cs+、Sr2+、Co2+、Ni2+、Fe3+的低浓度模拟废水,依次研究压力、离子浓度、pH值、乙二胺四乙酸二钠(EDTA)等因素对膜处理模拟废液中各金属离子脱盐率的影响。实验结果表明:模拟废水在pH值等于7,加入1:2.5的0.15 mol/L EDTA条件下,用超滤-反渗透(UF-RO)膜组合工艺处理时,Cs+、Sr2+、Co2+、Ni2+、Fe3+的脱盐率均达到95%以上;放射性蒸残液用EDTA螯合后,通过UF-RO-RO处理,去污效率可达到95.7%。

According to the characteristics of radionuclide exists in the low-level radioactive reactor waste water from HFETR, we use a new combined membrane process separation technology to study the efficient treating of low-lever radioactive reactor wastewater. First, the prepared the simulated wastewater contained Cs＋, Sr2＋, Co2＋, Ni2＋, and Fe3＋. Then, we sequentially investigated the pressure, ion concentration, pH value and EDTA, which have effects on the desalination rate of membrane processing metal ions in wastewater. The results show that： in the condition of pH = 7, and added 0.15mol/L EDTA, the simulated wastewater separated by UF-RO, desalination rates of Cs＋, Sr2＋, Co2＋, Ni2＋ and Fe3＋ are all above 95%; In the subsequent trials, adding 0.15mol/L EDTA into the radioactive residuary solution, and then treating by UF-RO-RO, the decontamination efficiency can reach 95.7%.