压水堆一回路模拟腐蚀氧化物的溶解去污试验

TEST OF DISSOLUTION DECONTAMINATION OF SIMULATED CORROSION-OXIDES IN PRIMARY LOOP OF PWR

本文介绍了对两种压水反应堆一回路模拟腐蚀氧化物 (铁镍铬氧化物和铁镍氧化物 )的溶解去污试验结果。选择的去污剂为 0 .3%草酸、0 .1%柠檬酸和 0 .1%高锰酸钾。结果表明 ,实验温度为 95℃、去污时间在 6～ 4 8h范围内 ,0 .3%草酸对铁镍铬氧化物和铁镍氧化物的溶解率分别为 2 4 .1%～ 6 5 .3%和 4 .9%～ 6 4.4 % ;0 .1%柠檬酸对二者的溶解率分别为 2 .2 %～ 4 .4 %和 0 .37%～ 1.5 5 % ;0 .1%高锰酸钾对二者几乎没有溶解作用。采用在草酸或柠檬酸去污前使用高锰酸钾去污剂的二步去污法 。

This paper introduces test results of dissolution decontamination of two kinds of simulated corrosion oxides (iron/nickel/chromium oxide Ni 0.6 Cr 0.15 Fe 2.25 O 4 and nickel ferrite oxide Ni 0.6 Fe 2.4 O 4) in primary loop of PWR. 0.3% oxalic acid, 0.1% citric acid and 0.1% potassium permanganate were selected as the decontaminating reagents. The results show that, dissolving ratios of two oxides range from 24.1% to 65.3% and from 4.9% to 64.4% respectively for 0.3% oxalic acid at temperature of 95 ℃, test time between 6 h to 48 h. While for 0.1% citric acid, dissolving ratios of two oxides range from 2.2% to 4.4% and from 0.37% to 1.55% respectively. 0.1% potassium permanganate is almost no use for dissolving two kinds of oxides. When using two step decontamination process (potassium permanganate plus oxalic acid or potassium permanganate plus citric acid), dissolving ratios of two oxides are lower than those using one step process (using oxalic acid alone or citric acid alone as decontaminating reagents). (