Treatment of Low Level Radioactive Waste Liquid by Air Gap Membrane Distillation

Low level radioactive waste liquid occupies a large proportion of radioactive waste. China has formulated strict emission standards, especially for inland nuclear power plant, which need to choose more efficient processing technology, it is necessary to study the purification effect of treatment of low level radioactive waste liquid by membrane distillation. Research on the purification effect of treatment of trace Sr²⁺ and Cs⁺ in simulating low level radioactive waste liquid by air gap membrane distillation, and the effect of the temperature difference and flow rate on the purifying effect, the low level radioactive waste liquid in spent fuel reprocessing plant were treated. Research shows that: the average retention rates of trace Sr²⁺ and Cs⁺ by membrane distillation are greater than 99.99%, which the decontamination factor can reach more than 10⁴ orders of magnitude; the temperature difference and flow rate have no effect on the purifying effect of membrane distillation; membrane distillation processes the low level waste liquid without any pretreatment, in more 4 days the average total alpha activity concentration of the distilled liquid is 0.04 Bq/L, the average total beta activity concentration is 15.13 Bq/L, far below the discharge standard of the spent fuel reprocessing plant.