| 摘要 |
The present invention relates to a decontamination method for a coolant pump in a Korea nuclear reactor. The decontamination method for a coolant pump in a Korea nuclear reactor includes a measuring process for measuring the thickness of an oxide film using a value recognized by a control unit through a sensor unit which is installed on the inside wall of a decontamination tank to measure the thickness of the oxide film formed on a coolant pump to be decontaminated by the decontamination tank of the coolant pump. According to the thickness of the oxide film measured in the measuring process, a process of setting the number of repetitions of a decontamination process is set in advance in a control unit. One round of a unit process of the decontamination process includes: an oxidation process of dissolving the oxidation film using a process water having a high hydrogen ion concentration in which nitric acid and permanganate of potassium are mixed to pure water; a chemical decomposition process of adding oxalic acid to the process water passing through the oxidation process to dissolve the residual oxidation film; a reduction process of adding oxalic acid, citric acid, and lithium hydroxide (LiOH) to the process water passing through the chemical decomposition process for complexing of metal ions; a purification process of regenerating the process water into pure water; and a pure water cleaning process of cleaning the surface of the coolant pump using the regenerated pure water. The unit process is repeated for the set number of times in the process of setting the number of repetitions of the decontamination process. |
