超临界水氧化处理核电站废阴离子交换树脂研究

在间歇式超临界水氧化(SCWO)设备中,对粉碎处理后的阴离子交换树脂水悬浮液在超临界条件下进行了氧化降解处理。实验研究了反应温度、反应压力、反应时间、过氧系数对COD去除率的影响,同时考察了催化剂种类、反应压力和反应温度对氨氮去除率的影响。通过正交试验,得到主要因素对处理效果影响的显著程度排序为:反应温度>反应压力>反应时间>过氧系数。结果表明:在反应温度540 ℃、反应压力26 MPa、反应时间8 min、过氧系数3的条件下,COD去除率为99.65%。针对阴离子树脂中NH₃-N含量高难以去除的问题,选用不同的催化剂CuSO₄、MnO₂、CeO₂添加到反应体系中,结果表明对NH₃-N的氧化效果顺序为CuSO₄>CeO₂>MnO₂,对NH₃-N的最高降解率达到96.53%。

Study on supercritical water oxidation of waste anion resin used in a nuclear power plant

A supercritical water oxidation (SCWO)equipment of batch-type was used to study the treatment of anion resin water suspension under supercritical conditions. The effects of reaction temperature, reaction pressure, reaction time, and oxidation coefficient on the removal rate of COD were investigated experimentally. At the same time, the effects of catalyst, reaction pressure and reaction temperature on ammonia removal rate were explored. Through an orthogonal experiment, the most significant factors influencing the reaction system are ranked as follows: reaction temperature>reaction pressure>reaction time>oxidation coefficient. The experiment results show that the removal rate of COD for anion resin is 99.65% under the conditions of reaction temperature of 540 ℃, reaction pressure of 26 MPa, reaction time of 8 min, and oxidation coefficient of 3. The content of NH₃-N in anion resin is high and difficult to be removed, so catalysts CuSO₄, MnO₂, and CeO₂ were added, and the catalytic effect was ranked as CuSO₄>CeO₂>MnO₂. The maximum removal rate of NH₃-N was 96.53%.