178results about "Conversion in nuclear reactor" patented technology

In a method of producing isotopes in a light water power reactor, one or more targets within the reactor may be irradiated under a neutron flux to produce one or more isotopes. The targets may be assembled into one or more fuel bundles that are to be loaded in a core of the reactor at a given outage. Power operations in the reactor irradiate the fuel bundles so as to generate desired isotopes, such as one or more radioisotopes at a desired specific activity or stable isotopes at a desired concentration.

A new transmutation assembly permits an efficient transmutation of a long-lived radioactive material (long-lived FP nuclides such as technetium-99 or iodine-129) which was produced in the nuclear reactor. Wire-type members of a long-lived radioactive material comprised of metals, alloys or compounds including long-lived FP nuclides are surrounded by a moderator material and installed in cladding tubes to form FP pins. The FP pins, and nothing else, are housed in a wrapper tube to form a transmutation assembly. The wire-type members can be replaced by thin ring-type members. The transmutation assemblies can be selectively and at least partly loaded into a core region, a blanket region or a shield region of a reactor core in a fast reactor. From a viewpoint of reducing the influence on the reactor core characteristics, it is optimal to load the transmutation assemblies into the blanket region.

A present invention provides an internal circulating irradiation capsule available for the production of iodine-125 and a related production method. The irradiation capsule filled with xenon gas has a lower irradiation part, an upper irradiation part, and a neutron control member. The lower irradiation part is inserted into an irradiation hole of a reactor core and irradiated with a large quantity of neutron directly. When neutron is radiated to the xenon gas, iodine-125 is produced from xenon gas. The upper irradiation part protrudes from the irradiation hole, and iodine-125 is transferred to the upper irradiation part by convection and solidified in the upper part. The neutron control member reduces neutron in the upper part to produce iodine-125 of high purity and radioactivity in a large quantity.

A combinatorial heterogeneous-homogeneous reactor configuration in which an array or groups of homogeneous fuel assemblies are interlinked together in a heterogeneous lattice. The present invention removes the limitation of a homogeneous reactor by providing a reactor concept that utilizes the inherent advantages of homogeneous fuel elements but in a heterogeneous fuel lattice arrangement that limits the power density of any one homogeneous fuel element and yet forms a reactor arrangement that is capable of producing any product demand of interest. The present invention provides a method for producing medical isotopes by the use of a modular reactor core comprised of homogeneous fuel assemblies arranged in a regular rectangular or triangular pitch lattice. The aqueous fuel solution is contained within individual fuel assemblies that are right circular cylinders clad in corrosion-resistant alloys such as stainless steel, zircalloy, zircalloy alloys, or other metal alloys that are resistant to corrosive fissile environments but preserve neutron economy. The fuel assemblies are supported below by a core plate that is tied directly to the lower reactor support structure. The bottom of each assembly opens into a common plenum area which provides a hydrodynamic communication / coupling path between the individual assemblies in the lattice. The fuel assemblies are supported above by an upper plate that is welded to each assembly tube. The top of each assembly opens to a common upper plenum which provides a means of thermodynamic pressure equalization among the four assemblies in the reactor core lattice.

Example embodiments are directed to methods of producing desired isotopes in commercial nuclear reactors and associated apparatuses using instrumentation tubes conventionally found in nuclear reactor vessels to expose irradiation targets to neutron flux found in the operating nuclear reactor. Example embodiments include assemblies for retention and producing radioisotopes in nuclear reactors and instrumentation tubes thereof. Example embodiments include one or more retention assemblies that contain one or more irradiation targets and are useable with example delivery systems that permit delivery of irradiation targets. Example embodiments may be sized, shaped, fabricated, and otherwise configured to successfully move through example delivery systems and conventional instrumentation tubes while containing irradiation targets and desired isotopes produced therefrom.

Example embodiments are directed to apparatuses and methods for producing radioisotopes in instrumentation tubes of operating commercial nuclear reactors. Irradiation targets may be inserted and removed from instrumentation tubes during operation and converted to radioisotopes otherwise unavailable from nuclear reactors. Example apparatuses may continuously insert, remove, and store irradiation targets to be converted to useable radioisotopes.

A system and method for employing the in-core movable detectors of a commercial nuclear powered electric generating facility to transmute a user-specified target material into a desired isotope. The process is conducted remotely resulting in a shielded end product available for shipment for further processing.

Various embodiments of a nuclear fuel assembly and related methods for processing and managing spent nuclear fuel are disclosed. According to one exemplary embodiment, a nuclear fuel may include a plurality of first fuel rods having a plurality of first fuel elements and a plurality of second fuel rods having a plurality of second fuel elements. Each of the first fuel elements may include uranium dioxide fuel, and each of the second fuel elements may include a plurality of tristructural isotropic fuel particles embedded in a silicon carbide matrix. The plurality of first fuel rods and the plurality of second fuel rods are arranged in a fuel assembly.

The present invention is related to an irradiation cell for producing a radioisotope of interest through the irradiation of a target material by a particle beam, comprising a metallic insert (2) forming a cavity (7) designed to house the target material and to be closed by an irradiation window, characterized in that said metallic insert (2) comprises at least two separate metallic parts (8,9) of different materials, being composed of at least a first part (8) comprising said cavity (7).

A radiocactive waste containing medium is circulated within two or more systems (1,2,3) separated from each other flowtechnically; and the circulated radioactive waste is exposed to neutron radiations of different energy spectrum in each system by operating a reactor physically united entirety of irradiated sections of the said systems as a nuclear reactor or an accelerator driven subcritical system. Each system (1,2,3) has a heat exchanger (9,10) and, in given cases, a circulating pump (10,21) and an expansion tank (5,16,27). The disclosed apparatus has two or more reactor regions (1,2,3) separated from each other by partitions (37,38) and, preferably, arranged coaxially within a reactor space encircled by a common shell structure (39). A particle beam (45) produced by a particle accelerator is preferably directed into the innermost reactor region (3).

Example embodiments are directed to methods of producing desired isotopes in commercial nuclear reactors and associated apparatuses using instrumentation tubes conventionally found in nuclear reactor vessels to expose irradiation targets to neutron flux found in the operating nuclear reactor. Example embodiments include irradiation targets for producing radioisotopes in nuclear reactors and instrumentation tubes thereof. Example embodiments include one or more irradiation targets useable with example delivery systems that permit delivery into instrumentation tubes. Example embodiments may be sized, shaped, fabricated, and otherwise configured to successfully move through example delivery systems and conventional instrumentation tubes while producing desired isotopes.

The present invention related to a novel process for accelerating the breeding and conversion of fissile fuel in various types of nuclear reactors. In said process a movable nuclear fuel ball bed filled with a coolant creeps through the reactor core. The said process could provide higher specific power per unit fuel volume inside the reactor core and proceed on-line refueling, thus requires much less initial fissile fuel inventory per unit power output as compared with the traditional breeding or conversion reactors. The said process has full inherent safety characteristics and could follow the external power demand with the inherent negative temperature coefficient of reactivity. The said process, therefore, is a more efficient and economic approach to meeting the enormous demand of fissile fuel for the forthcoming “second nuclear era”.

Targetry coupled separation refers to enhancing the production of a predetermined radiation product through the selection of a target (including selection of the target material and the material's physical structure) and separation chemistry in order to optimize the recovery of the predetermined radiation product. This disclosure describes systems and methods for creating (through irradiation) and removing one or more desired radioisotopes from a target and further describes systems and methods that allow the same target to undergo multiple irradiations and separation operations without damage to the target. In contrast with the prior art that requires complete dissolution or destruction of a target before recovery of any irradiation products, the repeated reuse of the same physical target allowed by targetry coupled separation represents a significant increase in efficiency and decrease in cost over the prior art.

A method of compressing a substance by impact in axisymmetric relativistic vacuum diodes (RVD) having a plasma cathode and an anode-enhancer including: producing an axisymmetric target of a condensed substance, which functions at least as a part of the anode-enhancer; axially placing said electrodes; and pulse discharge of a power source via the RVD. To compress a substantial portion of the target substance to a superdense state, a plasma cathode is used in the form of a current-conducting rod comprising a dielectric end element having the perimeter of the rear end embracing the perimeter of the rod in the plane perpendicular to the axis of symmetry with a continuous gap, and the area of the emitting surface being greater than the maximum cross-section area of the anode-enhancer; the anode-enhancer is placed towards the plasma cathode so that the center of curvature of the working surface of the anode enhancer is located inside the focal space of the collectively self focussing electron beam; and the anode-enhancer is acted upon by an electron beam with an electron energy not smaller than 0.2 MeV, current density not smaller than 106 A / cm2 and duration not greater than 100 ns.

A method of producing radioisotopes using a heavy water type nuclear power plant is provided. The method includes inserting targets (37) into a heavy water moderator of the heavy water reactor througha guide tube (30) in a port (55) in a reactivity mechanism deck (45) of the heavy water reactor. The heavy water reactor operates to irradiate the target to convert the target into a radioisotope. The method then includes removing the radioisotope from the moderator of the heavy water reactor via the reactivity mechanism deck. A heavy water nuclear reactor is also provided.

A high-temperature and high-pressure corrosion-resistant process heat exchanger for a nuclear hydrogen production system decomposes sulfite (SO3) using heat from a high-temperature gas-cooled reactor to thereby produce sulfide (SO2) and oxygen (O2). The process heat exchanger comprises second and third system coolant channels, each of which is defined by a heat transmission fin, which is bent in a quadrilateral shape, and heat transmission plates, and has increased corrosion resistance thanks to ion-beam coating and ion-beam mixing using a material having high corrosion resistance. The third system coolant channel includes reaction catalysts for SO3 decomposition, and is made of a super alloy. Thus, a system differential pressure between the second and third system coolant channels can be greatly maintained at a high temperature of 900° C. or higher.

A target holding device according to an embodiment of the invention includes a plurality of target plates, each target plate having a first surface and an opposing second surface, wherein the first surface has a plurality of holes. A shaft may be used to facilitate the alignment and joinder of the target plates such that the first surface of one target plate contacts a second surface of an adjacent target plate. The target holding device may optionally include end plates arranged to sandwich the target plates therebetween and / or separator plates alternately arranged with the target plates. The target holding device may be used to produce brachytherapy and / or radiography targets (e.g., seeds, wafers) in a reactor core such that the targets have relatively uniform activity.

Various embodiments of a transportable nuclear power generator having a plurality of subcritical power modules are disclosed. Each of the plurality of subcritical power modules includes a fuel cartridge, a power conversion unit, and a housing substantially enclosing the fuel cartridge and the power conversion unit. The fuel cartridge contains a nuclear fuel and has a proximal end and a distal end. The power conversion unit includes a compressor turbine disposed at the proximal end of the fuel cartridge and a power turbine disposed at the distal end of the fuel cartridge. At least one of the plurality of subcritical power modules is movable with respect to the other of the plurality of subcritical power modules between a first position and a second position to control criticality of the nuclear fuel contained in the fuel cartridges of the plurality of subcritical power modules.

The present invention is related to an irradiation cell for producing a radioisotope of interest through the irradiation of a target material by a particle beam, comprising a metallic insert forming a cavity designed to house the target material and to be closed by an irradiation window, wherein said metallic insert comprises at least two separate metallic parts of different materials, being composed of at least a first part comprising said cavity.

The invention relates to a reactor simulator, in particular to a uniform inner heat source simulator of a medical isotope production solution reactor, comprising a power simulation part and a fissiongas simulation part, wherein the power simulation part comprises a heating component and a heat exchange component, and the fission gas simulation part comprises a bubble generation device and simulation gas. The invention really reflects power distribution of fuel solution in the reactor, efficiently simulates power distribution of a prototype reactor, strictly controls occupied flow area of an electric heating element without causing great influence on natural convection heat exchange of the solution by the electric heating element, solves the problems of high simulation power and small cross section of the electric heating element in the prior art and satisfies the experimental requirements. In addition, nitrogen gas is used as the simulation gas so that the safety of an experiment is ensured.

Provided are methods to separate an isotope from a first solution including uranium. The methods may include (a) cleaning the first solution to form a second solution including the uranium and a third solution including the isotope; (b) oxidizing the third solution to form an oxidized isotope; and (c) separating the oxidized isotope.

The invention discloses an irradiated target containing Np-237 used for producing Pu-238 by means of research reactor irradiation. The irradiated target comprises a target barrel, and an upper end head and a lower end head which are arranged at both ends of the target barrel, wherein a target body to be irradiated is arranged inside the target barrel, the target body to be irradiated has high cooling performance and good cooling effect, and is suitable for producing the Pu-238 by means of research reactor irradiation. With the adoption of the irradiated target disclosed by the invention, the Pu-238 can be irradiated, the conversion rate is high and the safety is good.

A system for generating hydrogen includes a liquid metal nuclear reactor having a non-radioactive secondary heat loop, a steam generator connected to the secondary heat loop, a high temperature water cracking system, and a topping heater. The heat produced by the nuclear reactor is used to raise the temperature of the feed water for the cracking system to between about 450° C. to about 550° C. The topping heater raises the feed water temperature from the 450° C. to 550° C. range to at least 850° C. so that the cracking system can operate efficiently to produce hydrogen and oxygen.

A charged particle acceleration device according to some embodiments of the current invention includes a first triboelectric element, a second tribo-electric element arranged proximate the first tribo-electric element to be brought into contact with and separated from the first triboelectric element, an actuator assembly operatively connected to at least one of the first and second triboelectric elements to bring the first and second triboelectric elements into contact with each other and to separate the first and second triboelectric elements from each other, and a charged-particle source configured to provide charged particles in a gap between the first and second triboelectric elements.

The invention provides an inner circulation irradiation box which can be used to produce iodine-125 and a related production method. An irradiation box filled with xenon gas has a lower irradiation section and an upper irradiation section, and a neutron control member. The lower irradiation part is inserted into the irradiation hole of the reactor core and directly irradiated with a large amount of neutrons. Iodine-125 is produced from xenon gas when neutrons are irradiated to xenon gas. The upper irradiated portion protrudes from the irradiated hole, and iodine-125 is transported to the upper irradiated portion by convection and cured in the upper portion. The neutron control component reduces neutrons in the upper section to mass produce highly pure and highly radioactive iodine-125.

The invention discloses a Xenon target for producing iodine-125 through reactor irradiation and a preparation method thereof. The Xenon target comprises a barrel body, a sealing cap and a protection cap, wherein the upper part of the barrel body and the lower end of the sealing cap are subjected to argonarc welding, an air inlet is arranged at the upper end of the sealing cap, and Xenon is injected to the barrel body through the air inlet; and the air let is subjected to cold-welding sealing, and the protection cover covers the sealing cap. The target prepared by the invention by adopting a cold welding method is simple and convenient for operation, easy to control the charge quantity of target materials, and stable and reliable in performance in the process for producing iodine-125 through reactor irradiation, and has high pressure resistance.