无机纳滤膜处理低水平放射性废水的试验研究

Experimental Study on the Treatment of Low Level Radioactive Waste Water by Inorganic Nanofiltration Membrane

选择相对分子质量2000～5000的水溶性聚丙烯酸钠作为无机纳滤膜处理主要含^90Sr、^137Cs、^60Co放射性核素的低水平放射性废水的辅助药剂．重点考察了非放模拟废水的pH值及聚丙烯酸钠投加量对废水中锶、铯、钴等稳定核素截留率及膜通量的影响，并就影响机理做了初步探讨．得到较优的试验条件为：pH值7～8，聚丙烯酸钠体积浓度不低于0．1％．在优化的条件下，进行实际放射性废水的处理试验．结果表明，聚丙烯酸钠辅助无机纳滤膜处理低水平放射性废水是可行的，对总β和总γ的净化率均达到95％左右，且可得到满意的膜通量．

Soluble sodium poly（acrylic） acid （NaPAA） with molecular weight of 2 000- 5 000 was selected as an assistant reagent of inorganic nanofiltration membrane which was used to treat low level radioactive waste water mainly containing radionuclides ^90Sr, ^137Cs and ^60Co. The effect of non-active simulated wastewater pH and NaPAA concentration on the retention efficiency of non-active nuclides strontium, cesium and cobalt ions and membrane permeation flux were explored, and the effect mechanism was also preliminarily discussed. The optimum process parameters were decided： pH 7 - 8, NaPAA volume concentration no lower than 0.1%. Real radioactive waste water was treated under optimum experiment condition. The results show that the decontamination efficiency of total β and γ emitters of low-level radioactive wastewater were both up to about 95 % by inorganic nanofiltration assisted by NaPAA, and the permeation flux was also satisfying.