Abstract:
Ensemble (4) d'étanchéification d'une piscine d'installation nucléaire, comprenant : un revêtement (5) étanche comportant des ossatures (8) et des plaques (9) étanches fixées auxdites ossatures (8) et, un coffrage (6) destiné à venir en contact des plaques (9) étanches, des dispositifs (7) de plaquage du coffrage (6), lesdits dispositifs (7) de plaquage étant aptes à maintenir le coffrage (6) sur les plaques (9) étanches, ensemble (4) d'étanchéification dans lequel les dispositifs (7) de plaquage sont aptes à être fixés d'une part aux plaques (9) étanches et à maintenir d'autre part le coffrage (6) en contact avec lesdites plaques (9) étanches.
Abstract:
A means for installing material, through a fuel assembly instrument thimble insert, into the existing instrument thimbles in nuclear fuel assemblies for the purpose of allowing the material to be converted to commercially valuable quantities of desired radioisotopes during reactor power operations during a remainder of a fuel cycle and removing the radioisotopes from the core through the reactor flange opening once the fuel assemblies have been removed for refueling. The invention also describes methods that can be used to harvest the irradiated material so it can be packaged for transportation from the reactor to a location where the desired radioisotope(s) can be extracted from the fuel assembly instrument thimble insert.
Abstract:
An apparatus for supporting spent nuclear fuel. The apparatus may include a basket apparatus that is designed to be inserted into a cavity of a container or cask. The basket apparatus may be formed by arranging a plurality of slotted plates in an intersecting manner. The slotted plates may form fuel cells for storing fuel assemblies with spent nuclear fuel rods therein and flux trap spaces between adjacent ones of the fuel cells. Furthermore, the apparatus may include reinforcement members positioned in the flux traps to increase the structural strength of the basket apparatus.
Abstract:
An autonomous facility for storing spent nuclear fuel in one embodiment includes a building forming an enclosed interior space containing a water-filled spent fuel pool. The pool includes fuel racks containing spent fuel assemblies which heat the water via radioactive decay. A passive cooling system includes a submerged heat exchanger in the pool and an air cooled heat exchanger located in ambient air outside the building at a higher elevation than the pool heat exchanger. A heat transfer working fluid circulates in a closed flow loop between the heat exchangers via unpumped natural gravity driven flow to cool the fuel pool. The air cooled heat exchanger may be enclosed in a concrete reinforced silo adjoining the building for impact protection. The building may include a cask pit formed integrally with the pool to allow fuel assembles to be removed from a transport cask and loaded into the fuel rack underwater.
Abstract:
L'invention concerne un procédé de chargement d'éléments radioactifs (8) dans un emballage, comprenant les étapes suivantes :(a) mise en place, en piscine, d'une pluralité d'éléments radioactifs (8) dans un panier de rangement (30) équipé de moyens de protection radiologique (32); (b) extraction, en dehors de la piscine, du panier (30) chargé des éléments radioactifs (8); et (c) chargement dans l'emballage du panier (30) chargé des éléments radioactifs (8).
Abstract:
A module for storing high level radioactive waste includes an outer shell, having a hermetically closed bottom end, and an inner shell forming a cavity and being positioned inside the outer shell to form a space therebetween. At least one divider extends from the top to the bottom of the inner shell to create a plurality of inlet passageways through the space, each inlet passageway connecting to a bottom portion of the cavity. A plurality of inlet ducts each connect at least one of the inlet passageways and ambient atmosphere, and each includes an inlet duct cover affixed atop a surrounding inlet wall, the inlet wall being peripherally perforated. A removable lid is positioned atop the inner shell and has at least one outlet passageway connecting the cavity and the ambient atmosphere, the lid and the top of the inner shell being configured to form a hermetic seal therebetween.
Abstract:
容器に保持した液体が沸騰して液面レベルが低下するような事態になっても、アナログ処理のみで液面レベルを確実に検知する技術を提供する。 液面レベル検知装置において、複数のプローブの中からヒータに通電するプローブを選定するプローブ選定部31と、このプローブ選定部31で選定したプローブの温度センサの出力をアナログ量のまま温度信号V A (k)として入力する入力部と、ヒータへの通電に同期して温度信号V A (k)の処理信号V B (k)を出力する信号処理部34と、温度信号V A (k)及び処理信号V B (k)を演算処理して結果を出力する演算部35と、演算処理の出力結果に基づいて検出点が気相又は液相のいずれに存在するかを識別する気液識別部37と、気液識別部37の識別結果を示す表示部38とを、備える。
Abstract:
Ein Zwischenlagersystem (1) für Brennelemente (2) aus einer kerntechnischen Anlage soll bei Einhaltung hoher Sicherheitsstandards mit besonders geringem Aufwand eine zuverlässige Zwischenlagerung auch von Brennelementen (2) mit vergleichsweise hohem Abbrand erlauben. Dazu ist das Zwischenlagersystem (1) erfindungsgemäss für eine Nasslagerung der Brennelemente (2) ausgebildet, wobei ein Nasslagerbecken (14) über einen zugeordneten, im Naturumlauf betreibbaren Sekundärkühlkreislauf (22) rückkühlbar ist. Beim Betrieb des Zwischenlagersystems (1) wird ein im Nasslagerbecken (14) zur Kühlung der Brennelemente (2) vorgehaltenes Kühlmedium über den Sekundärkühlkreislauf (22) rückgekühlt, der seinerseits im Naturumlauf betrieben wird.
Abstract:
At least one irradiated product, such as a fuel assembly (1), is introduced into a metallic container (4) delimiting a chamber whose cross section is adapted to accommodate the cross section of a (single) product such as a fuel assembly (1). A neutral gas is introduced into the chamber of the container (4) and the chamber is sealed in tightly in such a way that the neutral gas cannot escape. The container (4) with the fuel assembly (1) is placed in a channel (10) of a storage facility, the container (4) and the fuel assembly (1) being positioned horizontally. Cooling air (25) which is in contact with the outer surface of the channel is circulated (10). Contamination inside the channel (10) can be monitored continually in a space (31) surrounding the container (4).