Refine your search:     
Report No.
 - 
Search Results: Records 1-5 displayed on this page of 5
  • 1

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

JAEA Reports

Design details of bottom shape for the 3rd glass melter in TVF

Asahi, Yoshimitsu; Shimamura, Keisuke*; Kobayashi, Hidekazu; Kodaka, Akira

JAEA-Technology 2021-026, 50 Pages, 2022/03

JAEA-Technology-2021-026.pdf:6.29MB

In Tokai Reprocessing Plant, the highly active liquid waste derived from a spent fuel reprocessing is vitrified with a Liquid-Fed Ceramic Melter (LFCM) embedded in Tokai Vitrification Facility (TVF). For an LFCM, the viscosity of melted glass is increased by the deposition of oxidation products of platinum group elements (PGE) and the PGE-containing glass tends to settle to the melter's bottom basin even after draining glass out. Removal of the PGE-containing glass is needed to avoid the Joule heating current from being affected by the glass, it requires time-consuming work to remove. For the early accomplishment of vitrifying the waste, Japan Atomic Energy Agency is planning to replace the current melter with the new one in which the amount of PGE sediments would be reduced. In the past design activities for the next melter, several kinds of shapes in regard to the furnace bottom and the strainer were drawn. Among these designs, the one in which the discharge ratio of PGE-containing glass would be as much as or greater than the current melter and which be able to perform similar operational sequences done in the current melter is selected here. Firstly, an operational sequence to produce one canister of vitrified waste is simulated for three melter designs with a furnace bottom shape, using 3D thermal-hydraulic calculations. The computed temperature distribution and its changes are compared among the candidate structures. After discussions about the technical and structural feasibilities of each design, a cone shape with a 45$$^{circ}$$ slope was selected as the bottom shape of the next melter. Secondly, five strainer designs that fit the bottom shape above mentioned are drawn. For each design, the fluid drag and the discharge ratio of relatively high viscosity fluid resting near the bottom are estimated, using steady or unsteady CFD simulation. By draining silicone oil from acrylic furnace models, it was confirmed experimentally that there are no vortices

JAEA Reports

XAFS measurement of simulated waste glass samples prepared from borosilicate glass frit including phosphorus pentaoxide (Joint research)

Nagai, Takayuki; Kobayashi, Hidekazu; Shimamura, Keisuke; Oyama, Koichi; Sasage, Kenichi; Okamoto, Yoshihiro; Shiwaku, Hideaki; Yamanaka, Keisuke*; Ota, Toshiaki*

JAEA-Research 2018-005, 72 Pages, 2018/09

JAEA-Research-2018-005.pdf:28.2MB

Addition of radioactive waste to a borosilicate glass frit affects the local structures of glass-forming elements and waste elements in a waste glass produced in a vitrification process. In this study, simulated waste glass samples were prepared from borosilicate glass frit including phosphorus pentaoxide, and we investigated local structures of sodium (Na), boron (B), and waste elements in these glass samples by using synchrotron XAFS measurements in soft and hard X ray region.

Oral presentation

Study on vitrification plan of high level liquid waste in the TVF, 6; Details of optimized strainer design for the next glass melter

Asahi, Yoshimitsu; Shimamura, Keisuke; Kobayashi, Hidekazu; Kodaka, Akira; Morikawa, Yo

no journal, , 

no abstracts in English

Oral presentation

Study on vitrification plan of high level liquid waste in the TVF, 5; Concept and configuration for the next glass melter

Shimamura, Keisuke; Asahi, Yoshimitsu; Kobayashi, Hidekazu; Kodaka, Akira; Morikawa, Yo

no journal, , 

no abstracts in English

Oral presentation

Basic research programs of vitrification technology for waste form reduction, 60; XAFS analysis of rare earth and platinum group elements in simulated borosilicate glasses including phosphorus

Okamoto, Yoshihiro; Shiwaku, Hideaki; Shimamura, Keisuke; Oyama, Koichi; Kobayashi, Hidekazu; Nagai, Takayuki

no journal, , 

The chemical state and local structure of platinum group and lanthanide elements in simulated borosilicate glasses including phosphorus were investigated by using synchrotron radiation based X-ray absorption and imaging techniques. By adding phosphorus to the simulated borosilicate glass samples, ratios of trivalent cerium (Ce(III)/Ce(IV)) and metallic rhodium (Rh/RhO$$_{2}$$) increased. They suggests that oxidation state in the glass changed to reductive by adding phosphorus. On the other hand, XAFS spectra of some elements like Mn, Fe, Zn, Sr, Y and Zr did not changed by adding phosphorus and showed almost the same profiles in each element.

5 (Records 1-5 displayed on this page)
  • 1