基于两级钯膜反应器的氚水处理技术

Investigation on Processing Technology of Tritiated Water Based on Two-Stage Palladium Membrane Reactor

为了处理高浓氚水,搭建了一台氢-水同位素交换串联水汽变换的两级钯膜反应器装置,可以实现级联处理工艺。以天然水代替氚水为源项,以D 2代替H 2开展了除氢实验,最高获得了207.4的除氢因子,验证了两级钯膜反应器用于处理氚水的可行性。通常情况下,水汽变换反应的除氢因子大于氢-水同位素交换反应。其中,氢-水同位素交换中D 2/H 2O体积流量比越大,该反应除氢因子越大;氢-水同位素交换中原料侧压力越大,该反应除氢因子越大;原料水流量越大,两个反应的除氢因子均会下降。由于一级膜反应器采用氢-水同位素交换可将氚水浓度降低1个量级以上,因而可以尽量避免二级膜反应器中CO与高浓氚接触,抑制含氚有机物的生成。由此可见,两级钯膜反应器有望成为一种高效的氚水处理装置。

In order to process highly tritiated water,a two-stage palladium membrane reactor with hydrogen-water isotope exchange series with water gas shift has been built,which can realize the cascade treatment process.In this paper,hydrogen removal experiments were carried out with natural water instead of tritiated water as the source and D 2 instead of H 2.The maximum decontamination factor(DF)of 207.4 is obtained,which verifies the feasibility of using two-stage palladium membrane reactor to treat tritiated water.In general,the DF of water gas shift reaction is greater than that of hydrogen-water isotope exchange reaction.The higher the ratio of D 2/H 2O in the hydrogen-water isotope exchange,the greater the DF.The higher the feed side pressure,the greater the DF.With the increase of feed water flow,the DF values of both reactions will decrease.Because hydrogen-water isotope exchange can reduce the concentration of tritiated water by more than one order of magnitude,the contact between CO and high concentration of tritium in the second membrane reactor can be avoided as far as possible,and the generation of tritium-containing organics can be inhibited.Thus it can be seen that the two-stage palladium membrane reactor is expected to be a highly efficient device for processing of tritiated water.