Abstract:
본 발명의 핵연료 제조용 UO2 혼합 분말의 제조 방법에 따르면, 혼합 시간이 짧으며, 제조된 UO2 혼합 분말의 혼합도 및 균질도가 우수하다. 본 발명은, 핵연료 제조용 UO2 혼합 분말의 제조 방법으로서, (a) UO2 분말, 기공형성제 및 윤활제를 자동 투입 장치를 이용하여 계량 및 체질하고, UC 컨테이너에 투입하는 단계; 및 (b) IBC Blender를 이용하여 상기 UO2 분말, 기공형성제 및 윤활제를 혼합하는 단계를 포함하는, 핵연료 제조용 UO2 혼합 분말의 제조 방법을 제공한다.
Abstract:
Thorium-based fuel bundles are used in existing PHWR reactors (e.g., Indian 220 MWe PHWR, Indian 540 MWe PHWR, Indian 700 MWe PHWR, CANDU 300/600/900) in place of conventional uranium-based fuel bundles, with little or no modifications to the reactor. The fuel composition of such bundles is 60+ wt % thorium, with the balance of fuel provided by lowenriched uranium (LEU), which has been enriched to 13-19.95% 235U. According to various embodiments, the use of such thorium-based fuel bundles provides (1) 100% of the nominal power over the entire life cycle of the core, (2) high burnup, and (3) non-proliferative spent fuel bundles having a total isotopic uranium concentration of less than 12 wt%. Reprocessing of spent fuel bundles is also avoided.
Abstract:
Изобретение относится к атомной промышленности, в частности, к технологии изготовления керамического ядерного топлива для тепловыделяющих элементов (ТВЭЛ) АЭС. Способ изготовления уран-гадолиниевого ядерного топлива включает подготовку исходного порошка диоксида урана, смешение с порошком закиси-окиси урана, с оксидом гадолиния, грануляция смеси порошков, смешение гранулята с твердой смазкой, прессование пресспорошка, спекание и шлифование полученных таблеток. К порошку на стадии грануляции, вводят часть добавки порообразователя, а оставшуюся часть порообразователя добавляют на стадии смешения гранулята с твердой смазкой. Способ обеспечивает стабильные технологические показатели уран-гадолиниевых таблеток, а именно оптимальную плотность и пористость топливных таблеток, которые непосредственно влияют на стабилизацию значений доспекаемости. Технический результат изобретения заключается в стабилизации «доспекаемости», что способствует безопасной эксплуатации топлива в реакторе.
Abstract:
Nuclear fuel, where it contains uranium telluride UTe2 and uranium germanide UGe2, where the uranium has a uranium 235U isotope enrichment of not more than 4.99% by weight, with uranium telluride UTe2 having a maximum enrichment of less than 5% and is proportional to powdered uranium germanide UGe2 in a ratio of 1 :9.
Abstract:
A uranium oxide fuel pellet (2) comprising an inner region (4) and an outer rim region (6) about the inner region (4), and that the fuel pellet (2) is cylindrical and the inner region (4) and outer rim region (6) are coaxial cylindrical regions.The outer rim region (6) has an excess of oxygen in comparison to the inner region (4), wherein high burnup structure (HBS) formation will be suppressed or delayed. Preferably, the excess oxygen is obtained by a chemical treatment by immersing the pellet in hydrogen peroxide (H 2 O 2 ) or potassium permanganate (KMnO 4 ) in solution.
Abstract:
Systems, structures, devices, and fabrication processes for ceramic matrix composites suitable for use in a nuclear reactor environment and other applications requiring materials that can withstand high temperatures and/or highly corrosive environments are disclosed. In one aspect, a ceramic composite structure is provided. The structure comprises a chamber including an external shell and a hollow space inside the external shell. The external shell includes an inner composite layer including a first composite structure, a middle composite layer placed outside of the inner composite layer, the middle composite layer including a second composite structure that is different from the first composite structure, and an outer monolithic layer that has a spatially uniform material property and placed outside of the middle composite layer.
Abstract:
A method for manufacturing a thorium oxide comprising material is described. The method comprising obtaining the thorium oxide comprising material, and sintering the thorium oxide comprising material, whereby at least during the sintering of the sintering process aluminum oxide is present as a sintering assisting additive. A resulting thorium oxide comprising material and a nuclear fuel comprising such material also are disclosed.
Abstract:
본 발명은 세라믹 핵연료의 균열을 방지하기 위해 기지상보다 더 많이 수축하는 조성의 세라믹이 코팅된 삼층구조 등방성 핵연료 입자를 포함하되, 코팅전의 삼층구조 핵연료 입자가 소결후를 기준으로 5 ~ 40 부피 분율 범위에서 포함되도록 하는 완전 세라믹 캡슐형 핵연료 소재의 제조방법에 관한 것으로서, 보다 상세하게는 상기 삼층구조 등방성 핵연료 입자의 코팅층의 소결 수축율을 ΔL C 라 하고, 상기 탄화규소 기지상의 소결 수축율을 ΔL m 으로 하였을 때, 상압소결시 ΔL C >ΔL m 인 조건이 만들어지는 것을 특징으로 하는 탄화규소 전구체로 부터 유도된 탄화규소를 주성분으로 하는 물질이 코팅된 삼층구조 등방성 핵연료 입자를 포함하는 완전 세라믹 캡슐형 핵연료 제조용 조성물, 이로부터 제조되는 소재 및 소재의 제조방법을 제공한다.상기 완전 세라믹 캡슐형 핵연료 소재의 잔존 기공율은 4% 이하인 것을 특징으로 한다.
Abstract:
La présente invention se rapporte à un procédé de frittage d'une poudre compactée d'au moins un oxyde d'un métal choisi parmi un actinide et un lanthanide, ce procédé comprenant les étapes successives suivantes, réalisées dans un four et sous une atmosphère comprenant un gaz inerte, du dihydrogène et de l'eau : (a) une montée en température d'une température initiale T i jusqu'à une température de palier T P (b) un maintien de la température à la température de palier T P , et (c) une descente en température depuis la température de palier T P jusqu'à une température finale T F , dans lequel le ratio P(H 2 )/P(H 2 O) est tel que : - 500 2 )/P(H 2 O) ≤ 50000, lors de l'étape (a), de T i jusqu'à atteindre une première température intermédiaire T i1 entre 1000°C et T P , et - P(H 2 )/P(H 2 O)≤ 500, au moins lors de l'étape (c), à partir d'une deuxième température intermédiaire T i2 entre T P et 1000°C, jusqu'à atteindre T F . L'invention se rapporte également à un procédé de fabrication d'une pastille d'au moins un oxyde d'un métal choisi parmi un actinide et un lanthanide, notamment d'une pastille de combustible nucléaire.