双膜法和吸附组合工艺深度处理高盐低放废液  

Reverse Osmosis-membrane Distillation-adsorption Combined Process for Advanced Treatment of High-salt and Low-level Radioactive Wastewater

作　　者：杨文文 郭浩城 赵宇伦 高鸽 陈凌[1] YANG Wenwen;GUO Haocheng;ZHAO Yulun;GAO Ge;CHEN Ling(China Institute of Atomic Energy,Beijing 102413,China;Sichuan Environmental Protection Engineering Co.,Ltd.,Guangyuan 628017,China)

机构地区：[1]中国原子能科学研究院,北京102413 [2]中核四川环保工程有限公司,四川广元628017

出　　处：《原子能科学技术》2025年第4期793-802,共10页Atomic Energy Science and Technology

基　　金：中核集团领创科研项目(LC202309001111)。

摘　　要：为有效处理核医药行业中的高盐低放废液,本文提出了一种反渗透-膜蒸馏+吸附组合工艺。实验中选择稳定核素配制含ReO_(4)^(-)、Cs^(+)和Ru^(3+)及0.9%NaCl的混合料液,探讨了操作条件对膜通量的影响,并分析了料液pH和离子浓度对核素截留性能的影响。结果表明:反渗透通量与进料压力线性相关,膜蒸馏通量随料液温度和流量的增加而升高,最高达27.07 kg/(m^(2)·h)。在pH=3~9范围内,反渗透截留性能受进料pH影响较大,而膜蒸馏对各核素的截留率均超过99.9%;膜蒸馏对各核素的截留率随核素浓度的增加呈显著上升趋势,去污因子达10~4以上;反渗透-膜蒸馏-吸附组合工艺对Re、Cs和Ru的总去污因子均超过10~4,且体积浓缩倍数达40,显示出其在处理钼锝发生器高盐低放废液方面的高效性。A combined process of reverse osmosis(RO),membrane distillation(MD) and adsorption was used to treat high-salt and low-radioactive wastewater.The use of molybdenum-technetium generators in the nuclear medicine industry generates some wastewater containing 0.9% NaCl and multiple radionuclides,such as ^(99)Tc,^(137)Cs and ^(106)Ru.Long-term exposure to ^(99)Tc and ^(137)Cs will cause a great damage to human health and even lead to cancer.Hence,in-depth research on the purification treatment of this wastewater is necessary.Perrhenate ions and stable isotope Ru and Cs were used to prepare a mixed feed solution consisting of ReO_(4)^(-),Cs^(+),Ru^(3+) and 0.9% NaCl.The effects of operating conditions(such as pressure,temperature,and flow rate) on the flux as well as the effect of feed solution pH and nuclide ion concentration on the retention performance of RO and MD processes were investigated.The RO flux is linearly related to the inlet water pressure,and the MD membrane fluxes increase with the increase of feed liquid temperature(50-75 ℃) and flow rate(30-90 L/h).Under the conditions of a hot side flow rate of 90 L/h and a hot side temperature of 75℃,MD membrane flux reaches a maximum of 27.07 kg/(m^(2)·h).The rejection rates of Re,Cs,and Ru are dependent upon the feed solution pH,and the minimum rejection rates for all nuclides are observed at the pH_(IEP) of the membrane(about 4).Due to the Donnan effect,the rejection rates of Cs and Ru increase when the feed solution pH is above 4,which also results in a high rejection rate of Re because of the electrostatic repulsions between the membrane and ReO_(4)^(-).In comparison,the rejection rates of nuclides during MD process slightly change(<0.1%) over the range of feed pH values(3-9),remaining a high level of99.9% or above.When the ion concentrations of Re,Cs and Ru exceed 0.75 mg/L,the rejection rates of RO for nuclides show an obvious decreasing trend,which is ascribed to the effect of concentration polarization.On the contrary,the rejection rates of membrane d

关 键 词：高盐低放废液 ^(99)Mo-^(99)Tc^(m)发生器 反渗透 膜蒸馏 吸附 去污因子 

分 类 号：TL941[核科学技术—辐射防护及环境保护]