1006results about "Reactors manufacture" patented technology

Known phosphate ceramic formulations are improved and the ability to produce iron-based phosphate ceramic systems is enabled by the addition of an oxidizing or reducing step during the acid-base reactions that form the phosphate ceramic products. The additives allow control of the rate of the acid-base reactions and concomitant heat generation. In an alternate embodiment, waste containing metal anions are stabilized in phosphate ceramic products by the addition of a reducing agent to the phosphate ceramic mixture. The reduced metal ions are more stable and / or reactive with the phosphate ions, resulting in the formation of insoluble metal species within the phosphate ceramic matrix, such that the resulting chemically bonded phosphate ceramic product has greater leach resistance.

An automatic celestial navigation system for navigating both night and day by observation of K-band or H-band infrared light from multiple stars. In a first set of preferred embodiments three relatively large aperture telescopes are rigidly mounted on a movable platform such as a ship or airplane with each telescope being directed at a substantially different portion of sky. Embodiments in this first set tend to be relatively large and heavy, such as about one cubic meter and about 60 pounds. In a second set of preferred embodiments one or more smaller aperture telescopes are pivotably mounted on a movable platform such as a ship, airplane or missile so that the telescope or telescopes can be pivoted to point toward specific regions of the sky. Embodiments of this second set are mechanically more complicated than those of the first set, but are much smaller and lighter and are especially useful for guidance of aircraft and missiles. Telescope optics focus (on to a pixel array of a sensor) H-band or K-band light from one or more stars in the field of view of each telescope. Each system also includes an inclinometer, an accurate timing device and a computer processor having access to catalogued infrared star charts. The processor for each system is programmed with special algorithms to use image data from the infrared sensors, inclination information from the inclinometer, time information from the timing device and the catalogued star charts information to determine positions of the platform. Direction information from two stars is needed for locating the platform with respect to the celestial sphere. The computer is also preferably programmed to use this celestial position information to calculate latitude and longitude which may be displayed on a display device such as a monitor or used by a guidance control system. These embodiments are jam proof and insensitive to radio frequency interference. These systems provide efficient alternatives to GPS when GPS is unavailable and can be used for periodic augmentation of inertial navigation systems.

Various embodiments of a nuclear fuel for use in various types of nuclear reactors and / or waste disposal systems are disclosed. One exemplary embodiment of a nuclear fuel may include a fuel element having a plurality of tristructural-isotropic fuel particles embedded in a silicon carbide matrix. An exemplary method of manufacturing a nuclear fuel is also disclosed. The method may include providing a plurality of tristructural-isotropic fuel particles, mixing the plurality of tristructural-isotropic fuel particles with silicon carbide powder to form a precursor mixture, and compacting the precursor mixture at a predetermined pressure and temperature.

Microparticles having a metal-containing core encapsulated in a graphitic shell containing hetero atoms are made by forming, in a liquid medium, colloidal particles containing a metal-oxo species of Fe, Co, Ni and Pd, colloidally stabilized by a surfactant and containing source material of carbon and the hetero atoms. These particles are pyrolyzed in inert gas to yield the microparticles. In an alternative method, silica gel coated particles are formed by colloidally stabilizing particles containing metal species and forming silica at the boundary of the stabilized particle.

A laminate film including at least one bio-based polyolefin layer including at least 53 pMC of radiocarbon (14C) content is disclosed. The laminate film may include additional layers such as a second bio-based polyolefin resin-containing layer of at least 53 pMC radiocarbon content, and a metal layer.

A precursor formulation of a silicon carbide material that includes a ceramic material and a boron-11 compound. The ceramic material may include silicon and carbon and, optionally, oxygen, nitrogen, titanium, zirconium, aluminum, or mixtures thereof. The boron-11 compound may be a boron-11 isotope of boron oxide, boron hydride, boron hydroxide, boron carbide, boron nitride, boron trichloride, boron trifluoride, boron metal, or mixtures thereof. A material for use in a nuclear reactor component is also disclosed, as are such components, as well as a method of producing the material.

The invention relates to an installing method for a main pipeline of a coolant system of a nuclear power station, which is characterized in that the main pipeline of the coolant system of a reactor of the pressurized water reactor nuclear power station comprises a cool section (41) and a hot section (42), and a steam generator is directly connected with a main pump. According to the invention, the problem that the main pipeline is installed and welded by only a pressure container or steam generator in place by adopting the installing method of the main pipeline without a transition section issolved, and technical limit that the main pipeline is installed after the pressure container is in place and the steam generator or main pump is in place in the traditional main pipeline constructiontechnology is eliminated. A main pipeline groove is processed by adopting a site numerical control machining technology, the main pipeline and equipment connected with the main pipeline are subjectedto measurement, modeling and process monitoring by adopting a laser tracking measuring and 3D modeling technology, the main pipeline is regulated to meet the assembly welding requirement and is installed by using a narrow TIG (argon tungsten-arc welding) automatic welding technology, thus a feasible method is provided for shortening the construction period of the nuclear power station.

Core debris generated during a molten reactor core in a reactor containment vessel penetrating the reactor containment vessel is configured to be caught by a core catcher located beneath the reactor containment vessel which has a main body having first stage cooling water channels and second stage surrounded by cooling fins extending radially. The number of the second stage cooling channels is larger than that of the first stage cooling channels. Cooling water is supplied from a cooling water injection opening and distributed to the first cooling water channels at a distributor. An intermediate header is formed between the first and the second cooling water channels, and the cooling water is distributed to the second cooling water channels uniformly.

A method of providing an end-capped tubular ceramic composite for containing nuclear fuel (34) in a nuclear reactor involves the steps of providing a tubular ceramic composite (40), providing at least one end plug (14, 46, 48), applying (42) the at least one end plug material to the ends of the tubular ceramic composite, applying electrodes to the end plug and tubular ceramic composite and applying current in a plasma sintering means (10, 50) to provide a hermetically sealed tube (52). The invention also provides a sealed tube made by this method.

A method is described herein for coating the substrate of a component for use in a water cooled nuclear reactor to provide a barrier against corrosion. The method includes providing a zirconium alloy substrate; and coating the substrate with particles selected from the group consisting of metal oxides, metal nitrides, FeCrAl, FeCrAlY, and high entropy alloys. Depending on the metal alloy chosen for the coating material, a cold spray or a plasma arc spray process may be employed for depositing various particles onto the substrate. An interlayer of a different material, such as a Mo, Nb, Ta, or W transition metal or a high entropy alloy, may be positioned in between the Zr-alloy substrate and corrosion barrier layer.

A metal particulate fuel system is described. The metal fuel system may include particulate metal fuel for use in nuclear reactors. The particulate metal fuel may include a plurality of particles of at least one enriched alloy where the particles are compacted into a fuel column. The metal particulate fuel system may also include a cladding and / or a gas-filled plenum.

A novel containment system for encapsulating nuclear fuel particles is disclosed. The containment system has a gas-impervious ceramic composite hollow shell having a spheroidal or ovoidal shape. The shell has a pair of longitudinally aligned round openings that are sealed with a gas-impervious ceramic composite tube to define a cavity between the shell inner surface and the tube outer surface. A ceramic composite matrix containing the nuclear fuel particles is enclosed within the cavity. The ceramic composite matrix has a controlled porosity, and can contain moderators or neutron absorbing material. The tube and shell are composed of a ceramic matrix composite material composed of ceramic reinforcement material that is bound together by a polymer-derived ceramic material.

The present invention relates to the use of a mixed carbonate of formula AB(CO3)2, in which A and B are different and chosen from alkali metals, alkaline-earth metals and rare earths, for the containment of radioactive carbon. This use may for example involve a process comprising: mixing C02 having a radioactive carbon to be contained, or a simple carbonate of an alkali, alkaline-earth or rare-earth metal having a radioactive carbon to be contained, with an aqueous solution of a mixture of ACln and BClm or with an aqueous solution of a mixture of A(OH)n and B(OH)m in order to obtain a precipitate of AB(CO3)2, where n and m are integers sufficient to compensate for the charge of A and B respectively; recovery of the AB(CO3)2 precipitate in powder form; and then pressing and sintering of the powder at a temperature below the decarbonation temperature of the mixed carbonate manufactured in order to obtain sintered pellets of mixed carbonates for the containment of the radioactive carbon.

The invention relates to a nuclear fuel cladding totally or partially made of a composite material with a ceramic matrix containing silicon carbide (SiC) fibers as a matrix reinforcement and an interphase layer provided between said matrix and said fibers, the matrix including at least one carbide selected from titanium carbide (TiC), zirconium carbide (ZrC), or ternary titanium silicon carbide (Ti3SiC2).When irradiated and at temperatures of between 800° C. and 1200° C., said cladding can mechanically maintain the nuclear fuel within the cladding while enabling optimal thermal-energy transfer towards the coolant.The invention also relates to a method for making the nuclear fuel cladding.

A fuel element for nuclear power generation made up of at least one coated UO2 fuel kernel embedded in a matrix containing Zr. The kernel and the element each having a coating that provides desired spacing and fission product barrier protection. The fuel enables the functioning and deployment of small scale nuclear reactors with a various features desired for deployment of such devices in developing nations, with limited electrical distribution infrastructure.

A nuclear fuel element for use in water-cooled nuclear power reactors and an improved multilayered silicon carbide tube for use in water-cooled nuclear power reactors and other high temperature, high strength thermal tubing applications including solar energy collectors. The fuel element includes a multilayered silicon carbide cladding tube. The multilayered silicon carbide cladding tube includes (i) an inner layer; (ii) a central layer; and (iii) a crack propagation prevention layer between the inner layer and the central layer. A stack of individual fissionable fuel pellets may be located within the cladding tube. In addition, a thermally conductive layer may be deposited within the cladding tube between the inner layer of the cladding tube and the stack of fuel pellets. The multilayered silicon carbide cladding tube may also be adapted for other high temperature, high strength thermal tubing applications including solar energy collectors.

The invention relates to a multilayer tubular part (1) comprising a metal layer forming a metal tubular body (3) and two layers in ceramic matrix composite material covering the metal tubular body, wherein one of the two layers in ceramic matrix composite material covers the inner surface of the metal tubular body to form an inner tubular body (4), whilst the other of the two layers in ceramic matrix composite material covers the outer surface of the metal tubular body to form an outer tubular body (2), the metal tubular body therefore being sandwiched between the inner and outer tubular bodies. The metal tubular body is in metal or metal alloy. Finally, the metal tubular body has a mean thickness smaller than the mean thicknesses of the inner and outer tubular bodies. A said part is useful in particular for producing nuclear fuel claddings.

Methods for manufacturing porous nuclear fuel elements for use in advanced high temperature gas-cooled nuclear reactors (HTGR's). Advanced uranium bi-carbide, uranium tri-carbide and uranium carbonitride nuclear fuels can be used. These fuels have high melting temperatures, high thermal conductivity, and high resistance to erosion by hot hydrogen gas. Tri-carbide fuels, such as (U,Zr,Nb)C, can be fabricated using chemical vapor infiltration (CVI) to simultaneously deposit each of the three separate carbides, e.g., UC, ZrC, and NbC in a single CVI step. By using CVI, a thin coating of nuclear fuel may be deposited inside of a highly porous skeletal structure made, for example, of reticulated vitreous carbon foam.

All possible loading patterns for a nuclear reactor core are searched and optimized for compliance with design constraints. The fuel inventory is divided into a few batches according to coarse levels of reactivity. A recursive enumeration process identifies patterns meeting selected core position constraints, which can be user modified to adjust the search space size. For the batch loading patterns satisfying the constraints, the batches are divided into several smaller batches. A sensitivity matrix linearizing the relationship between fuel assembly position and the depletion model is processed through mixed integer linear programming with branching and bounding to identify an optimal daughter loading pattern. The process is repeated through several levels of batch refinement and selection of optimal daughter patterns, including a level where burnable absorbers are assigned to feed assemblies, until the individual fuel assembly level is reached. The multiple optimal patterns remaining provide a range of solutions.

A composite nuclear fuel pellet comprises a composite body including a UO2 matrix and a plurality of high aspect ratio particies dispersed therein, where the high aspect ratio particies have a thermal conductivity higher than that of the UO2 matrix. A method of making a composite nuclear fuel pellet includes combining UO2 powder with a predetermined amount of high aspect ratio particles to form a combined powder, the high aspect ratio particles having a thermal conductivity higher than that of the UO2 powder; mixing the combined powder in a solvent to disperse the high aspect ratio particles in the UO2 powder; evaporating the solvent to form a dry mixture comprising the high aspect ratio particles dispersed in the UO2 powder; pressing the dry mixture to form a green body; and sintering the green body to form the composite fuel pellet.

The invention relates to compositions and methods for coating a zirconium alloy cladding of a fuel element for a nuclear water reactor. The coating includes a first tier or layer and a second tier or layer. The first layer includes an elemental metal and the second layer is an oxidation-resistant layer that includes elemental chromium. The first layer serves as an intermediate layer between the zirconium alloy substrate and the second layer. This intermediate layer can be effective to improve adhesion of the second layer to the zirconium alloy substrate. The multilayer coating forms a protective layer which provides improved capability for the zirconium alloy cladding to withstand normal and accident conditions to which it is exposed in the nuclear reactor.

A nuclear fuel cladding tube for a liquid-metal or molten-salt cooled reactor includes a tubular body of metal material and a protective coating applied on an outer surface of the tubular body, to contact the coolant. The coating includes at least one layer of coating material selected from the group consisting of ceramic materials, refractory metals, and FeCrAlY alloys, and includes a matrix composed of the coating material in amorphous phase, inside which nanodomains composed of the coating material in crystalline phase are dispersed.

The invention relates to a nuclear fuel cladding comprising: i) a substrate containing a zirconium-based inner layer, optionally coated with at least one intermediate layer formed by at least one intermediate material selected from among tantalum, molybdenum, tungsten, niobium, vanadium, hafnium or the alloys thereof; and ii) at least one protective outer layer placed on the substrate and formed by a protective material selected from either chromium or an alloy of chromium. The nuclear fuel cladding produced using the method of the invention has improved resistance to oxidation / hydriding. The invention also relates to the method for the production of the nuclear fuel cladding by ion etching of the surface of the substrate and deposition of the outer layer on the substrate with a high power impulse magnetron sputtering method (HiPIMS), as well as to the use thereof to protect against oxidation and / or hydriding.

A method and apparatus is disclosed for smoothly inserting a fuel rod loader through the skeleton of a fuel cell and then for pulling an attached fuel rod into the fuel rod skeleton while keeping the fuel rod under constant tension and preventing the bowing of the fuel rod. The pulling mechanism comprises a smooth collet with a smooth bullet end cap for guiding the puller mechanism into and through the skeleton where the bullet end cap is removed and the fuel rod is attached with a unique ball and slide mechanism actuated by a long puller rod that grabs the end of the fuel rod by a forward motion of the puller rod and is easily removed from the fuel rod by reversing this motion once the fuel rod is in place.

A sheathed, annular metal fuel system is described. A metal fuel pin system is described that includes an annular metal nuclear fuel alloy. A sheath may surround the metal nuclear fuel alloy, and a cladding may surround the sheath. A gas plenum may also be present. Mold arrangements and methods of fabrication of the sheathed, annular metal fuel are also described.

Microstructured nuclear fuel adapted for nuclear power system use includes fissile material structures of micrometer-scale dimension dispersed in a matrix material. In one method of production, fissile material particles are processed in a chemical vapor deposition (CVD) fluidized-bed reactor including a gas inlet for providing controlled gas flow into a particle coating chamber, a lower bed hot zone region to contain powder, and an upper bed region to enable powder expansion. At least one pneumatic or electric vibrator is operationally coupled to the particle coating chamber for causing vibration of the particle coater to promote uniform powder coating within the particle coater during fuel processing. An exhaust associated with the particle coating chamber and can provide a port for placement and removal of particles and powder. During use of the fuel in a nuclear power reactor, fission products escape from the fissile material structures and come to rest in the matrix material. After a period of use in a nuclear power reactor and subsequent cooling, separation of the fissile material from the matrix containing the embedded fission products will provide an efficient partitioning of the bulk of the fissile material from the fission products. The fissile material can be reused by incorporating it into new microstructured fuel. The fission products and matrix material can be incorporated into a waste form for disposal or processed to separate valuable components from the fission products mixture.

A method of manufacturing nuclear fuel elements comprising the steps of placing nuclear fuel balls in the container made from ultra-porous material, applying a CVI to the container and removing the container. The container for manufacturing fuel elements comprising balls, and is produced from at least one ultra-porous material, for example carbon foam.

Core debris generated during a molten reactor core in a reactor containment vessel penetrating the reactor containment vessel is configured to be caught by a core catcher located beneath the reactor containment vessel which has a main body having first stage cooling water channels and second stage surrounded by cooling fins extending radially. The number of the second stage cooling channels is larger than that of the first stage cooling channels. Cooling water is supplied from a cooling water injection opening and distributed to the first cooling water channels at a distributor. An intermediate header is formed between the first and the second cooling water channels, and the cooling water is distributed to the second cooling water channels uniformly.

The invention relates to a modular steel containment vessel annular hanging beam and an assembling method thereof. The annular hanging beam has a simple structure, and is convenient to use; and high-altitude assembling and welding operation is avoided and the safety risk of the operating process is lowered greatly. The annular hanging beam comprises a plurality of containment vessel arc plates which are spliced to form an entire ring; the inner wall of each containment vessel arc plate is provided with a plurality of annular hanging beam modules so as to constitute a split annular hanging beam; each annular hanging beam module comprises an upper annular plate and a lower annular plate; and a rib plate and a vertical plate are connected between the upper annular plate and the lower annularplate.