Abstract:
The invention relates to nuclear energy based on the use of thorium as a nuclear fuel. Said invention makes it possible to efficiently control a nuclear reactor by modifying (shifting) a neutron energy spectrum in the active zone of the nuclear reactor, extend the service time of the nuclear reactor to 30-50 years with a single charging of nuclear fuel, practically stop the production of plutonium and other transuranic elements, exclude a sequential radiochemical transformation of spent nuclear fuel (SNF), thereby excluding any external transportation of the SNF and to significantly improve the ecological safety of nuclear energy. Control of the thorium nuclear reactor is carried out by modifying the neutron energy spectrum in the active zone of the reactor by supplying neutron decelerators in the gaseous form thereof at a controlled pressure ranging from a normal value to one hundred and more atmospheres to fuel elements. The inventive fuel assembly for thorium reactors comprises the fuel elements and is provided with a central distributor and/or a peripheral collector for supplying the gaseous neutron decelerators.
Abstract:
A method of operating a reactor, which can minimize effectively SCC generation and growth in a BWR reactor structural material and reduce a reactor water radioactivity without increasing a dose rate of a main steam system by performing at a proper timing a control for injecting hydrogen while adjusting a reactor water pH to an alkaline side. Specifically, a first invention controls a reactor water pH at room temperature to within a range, 8.5
Abstract:
The object of the invention is the production of a fuel element capable of containing the actinide alone, under conditions ensuring that its integrity is maintained throughout the incineration process and allowing the recovery of the incineration products. This is achieved by an element having a tubular outer sleeve (30) and a tubular inner jacket (38), coaxial with the sleeve, so as to define an annular cavity (44) for receiving actinide particles (46) to be incinerated and a central inner space (42), wherein the inner jacket (38) is made of a material permeable to the incineration gases, but impermeable to actinides, and extends over a portion of the length of the sleeve (30) so as to define at least one expansion chamber (40) with which the central inner space (42) communicates.
Abstract:
The wetwell space in a suppression pool (26) of a nuclear reactor containment is continuously ventilated by exhausting gas therefrom, while at the same time, during normal system operation atmospheric air from a source of same is admitted to the wetwell but such admission being blocked during a LOCA. All exhaust flow from the wetwell is conveyed through a conduit that outlets at a remote elevated location in the atmosphere. All exhaust flow through the conduit (37) is before outletting therefrom passed through gas treatment operation (60) wherein any particulates in the gas mixture are removed. Further treatment of the gas with charcoal to adsorb noble gases can be carried out.
Abstract:
A recirculation system (10) is disclosed for driving reactor coolant water in an annular downcomer (118) defined between a reactor vessel and a core shroud (12) spaced radially inwardly therefrom. The system supplies feedwater to the vessel and to a turbopump (18) disposed inside the downcomer (118). The turbopump (18) in accordance with one embodiment of the present invention includes a stationary axle (22) and a pump impeller (26) rotatably joined thereto and having an inlet end for receiving the coolant water from the downcomer. An annular plenum (30) surrounds the impeller for channeling feedwater to a plurality of turbine blades (36) joined to the impeller for rotating the impeller for driving the coolant water. The impeller is lubricated solely by the feedwater upon rotation of the impeller about the axle.
Abstract:
A reactor core (104) includes upper and lower matrices of fuel bundles. Fuel rods in the upper matrix (126) have their plenums oriented upward, while fuel rods in the lower matrix (124) have their plenums oriented downward. Refueling involves removal of a first bundle in the upper matrix (126), removal and retirement of the bundle in the lower matrix (124) directly below the original position of the first bundle, inversion and installation of the first bundle in the lower matrix, and installation of a new bundle in the upper matrix. The new bundle is installed plenum-side up. The bi-level core (104) provides greater flexibility in repositioning fuel bundles for longer burnups and lower high-level waste. In particular, problems with axial spectral variations in neutron flux can be compensated using the disclosed core arrangement and refueling procedure.
Abstract:
A nuclear reactor adapted for generating energy and/or decontaminating nuclear fuel using a plurality of energy beam generating accelerator devices configured for inducing a photo-fission reaction in the nuclear fuel.
Abstract:
Изобретение относится к конструкциям легководных ядерных реакторов, в которых в качестве топлива применяется торий, в частности, к конструкциям бесчехловых тепловыделяющих сборок, из которых сформированы активные зоны водо-водяных энергетических реакторов, таких как реактор BBЭP-1000. В активной зоне ядерного реактора, содержащей топливную сборку из запального и воспроизводящего модулей, сжигается ториевое топливо в воспроизводящем модуле вместе с обычным реакторным топливом, включающим непрофилированный обогащенный уран или энергетический плутоний в запальном модуле. Запальный модуль содержит пучок топливных элементов, которые имеют трёхлепестковый профиль, образующий винтовые дистанционирующие рёбра. Запальный и воспроизводящий модули могут быть связаны между собой посредством замкового соединения или не иметь жёсткой механической связи. Конструкция топливной сборки в соответствии с изобретением обеспечивает её полную совместимость с существующими топливными сборками, используемыми в реакторах BBЭP-1000. Разборность двухсекционной топливной сборки позволяет обеспечить независимую перегрузку запального модуля.
Abstract:
Die Erfindung betrifft eine mehrschichtige Strahlenschutzwand zur Abschirmung von Gamma- und/oder Teilchenstrahlung eines Reaktionsplatzes an einer Beschleunigeranlage, wobei die Strahlenschutzwand einen sandwichartigen Aufbau aus zumindest einer ersten und zweiten Schichtanordnung umfasst, wobei die erste Schichtanordnung zumindest eine primäre Abschirmschicht und die zweite Schichtanordnung zumindest eine sekundäre Abschirmschicht umfasst. Dabei ist zumindest eine der ersten und zweiten Schichtanordnungen in eine Mehrzahl Teilabschnitten unterteilt, wodurch eine selektierte Entsorgung ermöglicht wird. Dadurch werden eine gesteigerte Kosteneffizienz erreicht und die Umweltbelastung verringert.
Abstract:
A nuclear-powered plant for systems of up to about 100 MWs with a confinement section where the reaction takes place in a core having a reactive thorium/uranium-233 composition, and where an external neutron source is used as a modulated neutron multiplier for the reactor core output. The core is housed in a containment structure that radiates thermal energy captured in a multiple-paths heat exchanger. The exchanger heat energy output is put to use in a conventional gas-to-water heat exchanger to produce commercial quality steam.