Study on efficiency of dry decontamination technique by numerical method, 3 (Joint research)

Hyakutake, Toru*; Muto, Akinori*; Sasakura, Mariko*; Minowa, Hirotsugu*; Suzuki, Kazuhiko*; Yokoyama, Kaoru; Takahashi, Nobuo; Hata, Haruhi; Sugitsue, Noritake

JAEA-Research 2011-035, 53 Pages, 2012/01

JAEA-Research-2011-035.pdf:3.13MB

System decontamination has been generally carried out with the aim of reducing the amount of radioactive waste generated and minimizing exposure to radiation released from nuclear fuel facilities. At the Ningyo-Toge Environmental Engineering Center, metal surfaces that are contaminated by uranium are dry decontaminated by using iodine heptafluoride (IF) as a system decontaminator. Only a few studies have been carried out on the decontamination efficiency, mechanism, level, etc. of dry decontamination techniques that use a decontamination gas. Therefore, the generalization of dry decontamination techniques is required. In the present study, the efficiency of a dry decontamination technique was assessed by a numerical method using decontamination data obtained at the Ningyo-Toge Environmental Engineering Center. A concrete analytical content is a depositing of uranium hexafluoride.

Study on efficiency of dry decontamination technique by numerical method (Joint research)

Hyakutake, Toru*; Muto, Akinori*; Sasakura, Mariko*; Minowa, Hirotsugu*; Suzuki, Kazuhiko*; Yokoyama, Kaoru; Takahashi, Nobuo; Tsunashima, Yasumichi; Ema, Akira; Sugitsue, Noritake

JAEA-Research 2009-047, 92 Pages, 2010/01

JAEA-Research-2009-047.pdf:5.13MB

System decontamination has been generally carried out with the aim of reducing the amount of radioactive waste generated and minimizing human exposure to radiation released from nuclear fuel facilities. At the Ningyo-Toge Environmental Engineering Center, metal surfaces that are contaminated by uranium are dry decontaminated by using iodine heptafluoride (IF) as a system decontaminator. In this dry decontamination technique, a chemical reaction occurs between the uranium compound attached to the metal surface and IF. Only a few studies have been carried out on the decontamination efficiency, mechanism, level, etc. of dry decontamination techniques that use a decontamination gas. Therefore, the generalization of dry decontamination techniques is required. In the present study, the efficiency of a dry decontamination technique was assessed by a numerical method using decontamination data obtained at the Ningyo-Toge Environmental Engineering Center.

Basic study on system decontamination by iodine heptafluoride, 2; Formulate of potential model for deposition mechanism of uranium compound

Hata, Haruhi; Yokoyama, Kaoru; Sugitsue, Noritake; Hyakutake, Toru*; Muto, Akinori*; Sasakura, Mariko*; Minowa, Hirotsugu*; Suzuki, Kazuhiko*

no journal, , 

As a first step to elucidate the molecular mechanism of decontamination systems for iodine heptafluoride, uranium hexafluoride and the metal (iron), the possibility of physical adsorption and chemical reactions with uranium hexafluoride and uranium tetrafluoride (solid), we investigate the possibility of physical adsorption and chemical reactions of this. Therefore, the intermolecular of uranium hexafluorides, iron and uranium hexafluoride, uranium tetrafluoride and uranium hexafluoride (solid) and evaluated by molecular orbital method to the intermolecular potential between, based on this data, MD law adhesion mechanism was estimated by uranium hexafluoride.

Basic study on system decontamination by iodine heptafluoride, 2; Formulate of potential model for deposition mechanism of uranium compound

Hata, Haruhi; Yokoyama, Kaoru; Takahashi, Nobuo; Sugitsue, Noritake; Hyakutake, Toru*; Sasakura, Mariko*; Minowa, Hirotsugu*; Suzuki, Kazuhiko*

no journal, , 

The IF treatment technique belongs to the systematic decontamination technology. It has the high performance decontamination technique for the plant that accumulates the uranium intermediate fluoride, such as UF, UF, UF, and UF, which exist in the uranium enrichment plant. This report will show the chemical reactions and the physical adsorption between the metal and the uranium fluoride on the molecular scale, which was calculated by the molecular dynamics method.

Radioactive cesium behavior analysis in the refuse incineration plant, 2; Combustion model building

Yokoyama, Kaoru; Sugitsue, Noritake; Ohara, Yoshiyuki; Takeda, Hiroshi*; Rong, D.*; Yanase, Shinichiro*; Kuwagi, Kenya*; Takami, Toshihiro*; Hyakutake, Toru*

no journal, , 

Some disaster wastes polluted with the radioactive cesium diffused in the accident of the Fukushima Daiichi Nuclear Power Plant are incinerated in the refuse incineration plant. It is thought that cesium is not emitted outside since cesium is coagulated to the refuse incineration ash and trapped by a bag filter or an electric dust collector. Therefore, we research concentration and particle size distribution of the refuse incineration ash. In this study, the combustion model is reported.

Radioactive cesium behavior analysis in the refuse incineration plant, 4; Simulation of the behavior of cesium in the incineration facility

Yokoyama, Kaoru; Sugitsue, Noritake; Ohara, Yoshiyuki; Takeda, Hiroshi*; Rong, D.*; Yanase, Shinichiro*; Kuwagi, Kenya*; Takami, Toshihiro*; Hyakutake, Toru*

no journal, , 

Some disaster wastes polluted with the radioactive cesium diffused in the accident of the Fukushima Daiichi Nuclear Power Plant are incinerated in the refuse incineration plant. It is thought that cesium is not emitted outside since cesium is coagulated to the refuse incineration ash and trapped by a bag filter or an electric dust collector. Therefore, we report on simulation results incorporating the adhesion model of cesium in the combustion model of waste.

Radioactive cesium behavior analysis in the refuse incineration plant, 7; Simulation for the case of urban garbage of high cesium concentration

Takahashi, Nobuo; Sugitsue, Noritake; Yokoyama, Kaoru; Ohara, Yoshiyuki; Yanase, Shinichiro*; Kochi, Toshinori*; Takami, Toshihiro*; Kuwagi, Kenya*; Hyakutake, Toru*; Takeda, Hiroshi*; et al.

no journal, , 

As part of the cesium behavior analysis in the incineration plant, we carried out simulation by urban garbage of high cesium density incinerated. We chose plant having the results that burnt up contaminated urban garbage with radiocesium, as the object of the analysis.