2020 年 5 巻 p. 80-85
Fuel debris retrieval and contaminated water analysis are some of the most important issues of post-Fukushima NPS accident. The information about the fuel debris and contaminated water properties is needed before starting the decommissioning. Due to the high radiation environment, remote analysis is required. In this study, the preliminary study on the development of elemental analysis in order to obtain the chemical element information of the liquid around the debris is presented. Also, the possibility of a combination with the existing flow measurement technique (Ultrasonic Velocity Profiler- UVP) for fuel debris retrieval is presented. The elemental analysis deploys the specific light emission from low-frequency ultrasonic sonication in aqueous solution. The external transducer was chosen to perform the sonication as it enables the remote analysis. The experiments were performed under a stagnant and flowing condition. The visualization of NaCl, KCl, LiCl aqueous solution in stagnant condition showed a different color for each element. The combination experiment under a flowing condition showed a possibility of combining the abovementioned method with the measurement gap at 13 cm between transducers.
