Study On Decontamination Technology Of Contaminatedusing Dry Ice On The Surface Of Nuclearfacilities(Sampling Cabinets)

In order to reduce the pollution level of the sampling cabinet of the nuclear facility,the difficulty of dismantling,the exposure dose of the decommissioning operators,and the prevention of the spread of pollution and secondary pollution caused by the dismantling and dismantling of the decommissioning.This paper takes nuclear facility sampling cabinet as the research object,researches on-line dry ice decontamination device and process,simulated sampling cabinet dry ice decontamination cold testing and hot testing,analyzes the design and process of online dry ice decontamination device and process control parameters on dry ice The effect of decontamination.The main work of this paper is as follows:(1)According to the situation of the decontamination operation site of the sampling cabinet and the structural characteristics of the sampling cabinet,the design and process research of the online dry ice decontamination device were carried out.The nozzles and linkage pipes suitable for the decontamination of the sampling cabinet were studied.A preliminary analysis of the operation capability of the equipment willeventually form an online dry ice decontamination device.(2)Using the developed online dry ice decontamination device to conduct a dry ice decontamination cold testing inside the simulated sampling cabinet to study the online dry ice decontamination process,the method for recovering solid particles,and process control parameters(such as nozzle spray angle,spray distance,spray Pressure,air pressure,exhaust volume,and negative pressure control of the sampling cabinet)affect the decontamination effect of the simulated sampling cabinet.(3)The on-line dry ice decontamination hot testing shall be carried out for the sampling cabinet in the nuclear facilities to further verify and adjust the process and technical parameters determined by the cold testing,forming a set of on-line decontamination process and technical specifications for the sampling cabinet.At the same time,in order to evaluate the decontamination effect,spot sampling measurements were taken on the inner surface of the sampling cabinet before and after the thermal experiment to calculate the decontamination coefficient and analyze and evaluate the feasibility of the online dry ice decontamination process of the sampling cabinet.