Development and decontamination efficiency of device using dry ice snow cleaning

The decontamination technology is essential in the operation of nuclear power plants. Water washing, steam blast cleaning, sand blast cleaning and hand work cleaning are currently used in removal of radioactive wastes absorbed on the work surface. However, these methods produce lots of secondary wastes and tend to damage the work surface A dry ice snow cleaning device with and adjustable nozzle was developed for the decontamination purpose. An adjustable nozzle to control the size of snow was developed. A cleaning device with this nozzle was devised and tested. Using this cleaning device, specimen contaminated with oil and dust were easy to remove. Decontamination ability was measured using a radioactive contaminated pump-housing surface. The maximum of 82% of radioactivity was reduced after dry ice snow cleaning. This device is expected to be used in decontamination of expensive electronic and optical instruments and detectors that cannot be decontaminated by water