Abstract: Nuclear fuel elements may include: a fuel zone including fuel particles disposed in parallel layers in a matrix including graphite powder; and a shell comprising graphite and surrounding the fuel zone. The fuel particles may include fissile particles, burnable poison particles, breeder particles, or a combination thereof. The fuel zone may include a central region and a peripheral region surrounding the central region, and a fuel particle density of the peripheral region may be greater than a fuel particle density of the central region.

Abstract: A method of manufacturing nuclear fuel elements may include: forming a base portion of the fuel element by depositing a powdered matrix material including a mixture of a graphite material and a fibrous material; depositing particles on the base portion in a predetermined pattern to form a first particle layer, by controlling the position of each particle in the first particle layer; depositing the matrix material on the first particle layer to form a first matrix layer; depositing particles on the first matrix layer in a predetermined pattern to form a second particle layer by controlling positions of each particle in the second particle layer; depositing the matrix material on the second particle layer to form a second matrix layer; and forming a cap portion of the fuel pebble by depositing the matrix material. The particles in the first particle layer and the second particle layer include nuclear fuel particles.

Abstract: Nuclear fuel elements may include: a fuel zone including fuel particles disposed in parallel layers in a matrix including graphite powder; and a shell comprising graphite and surrounding the fuel zone. The fuel particles may include fissile particles, burnable poison particles, breeder particles, or a combination thereof. The fuel zone may include a central region and a peripheral region surrounding the central region, and a fuel particle density of the peripheral region may be greater than a fuel particle density of the central region.

Abstract: A method of manufacturing nuclear fuel elements may include: forming a base portion of the fuel element by depositing a powdered matrix material including a mixture of a graphite material and a fibrous material; depositing particles on the base portion in a predetermined pattern to form a first particle layer, by controlling the position of each particle in the first particle layer; depositing the matrix material on the first particle layer to form a first matrix layer; depositing particles on the first matrix layer in a predetermined pattern to form a second particle layer by controlling positions of each particle in the second particle layer; depositing the matrix material on the second particle layer to form a second matrix layer; and forming a cap portion of the fuel pebble by depositing the matrix material. The particles in the first particle layer and the second particle layer include nuclear fuel particles.

Abstract: Nuclear fuel elements may include: a fuel zone including fuel particles disposed in parallel layers in a matrix including graphite powder; and a shell comprising graphite and surrounding the fuel zone. The fuel particles may include fissile particles, burnable poison particles, breeder particles, or a combination thereof. The fuel zone may include a central region and a peripheral region surrounding the central region, and a fuel particle density of the peripheral region may be greater than a fuel particle density of the central region.

Abstract: A method of manufacturing nuclear fuel elements may include: forming a base portion of the fuel element by depositing a powdered matrix material including a mixture of a graphite material and a fibrous material; depositing particles on the base portion in a predetermined pattern to form a first particle layer, by controlling the position of each particle in the first particle layer; depositing the matrix material on the first particle layer to form a first matrix layer; depositing particles on the first matrix layer in a predetermined pattern to form a second particle layer by controlling positions of each particle in the second particle layer; depositing the matrix material on the second particle layer to form a second matrix layer; and forming a cap portion of the fuel pebble by depositing the matrix material. The particles in the first particle layer and the second particle layer include nuclear fuel particles.

Abstract: Nuclear fuel elements may include: a fuel zone including fuel particles disposed in parallel layers in a matrix including graphite powder; and a shell comprising graphite and surrounding the fuel zone. The fuel particles may include fissile particles, burnable poison particles, breeder particles, or a combination thereof. The fuel zone may include a central region and a peripheral region surrounding the central region, and a fuel particle density of the peripheral region may be greater than a fuel particle density of the central region.

Abstract: A method of manufacturing nuclear fuel elements may include: forming a graphite base portion of the fuel element; depositing a first layer of graphite spheres on the base portion; depositing a first layer of fuel, burnable poison and/or breeder particles on the first layer of graphite spheres; forming a second layer of graphite spheres on the first layer of particles; depositing a second layer of fuel, burnable poison and/or breeder particles on the second layer of graphite spheres; and forming a graphite cap portion of the fuel element. Fuel, burnable poison and/or breeder particles of the first layer may be are spaced apart by substantially the same distance, and fuel, burnable poison and/or breeder particles of the second layer may be spaced apart by substantially the same distance. The fuel element may be a spherical fuel pebble. The fuel particles may be tri-structural-isotropic (TRISO) particles without an overcoat.

Abstract: A method of manufacturing nuclear fuel elements may include: forming a base portion of the fuel element by depositing a powdered matrix material including a mixture of a graphite material and a fibrous material; depositing particles on the base portion in a predetermined pattern to form a first particle layer, by controlling the position of each particle in the first particle layer; depositing the matrix material on the first particle layer to form a first matrix layer; depositing particles on the first matrix layer in a predetermined pattern to form a second particle layer by controlling positions of each particle in the second particle layer; depositing the matrix material on the second particle layer to form a second matrix layer; and forming a cap portion of the fuel pebble by depositing the matrix material. The particles in the first particle layer and the second particle layer include nuclear fuel particles.

Abstract: A method of manufacturing nuclear fuel elements may include: forming a graphite base portion of the fuel element; depositing a first layer of graphite spheres on the base portion; depositing a first layer of fuel, burnable poison and/or breeder particles on the first layer of graphite spheres; forming a second layer of graphite spheres on the first layer of particles; depositing a second layer of fuel, burnable poison and/or breeder particles on the second layer of graphite spheres; and forming a graphite cap portion of the fuel element, wherein, adjacent fuel, burnable poison and/or breeder particles of the first layer are spaced apart by substantially the same distance, and adjacent fuel, burnable poison and/or breeder particles of the second layer are spaced apart by substantially the same distance. The fuel element may be a spherical fuel pebble. The fuel particles may be tri-structural-isotropic (TRISO) particles without an overcoat.

Abstract: A method of producing low cost high thermal conductivity graphitic foils includes the steps of providing a plurality of partially purified waste flakes formed during iron smelting, and compacting the plurality of waste flakes into a flexible foil material. A thermally conductive foil includes a plurality of partially purified pressed waste flakes derived from iron smelting, the foil having trace impurities characteristic of formation during iron smelting.

Abstract: A fully dense, high thermal conductivity graphite can be manufactured in a single hot-pressing step, without the need for multiple re-impregnation and baking steps as required in the standard processes. The ingredients of the blend, namely graphite filler which may or may not be reduced in size, and a binder, are dry mixed at room temperature, below the melting point of the binder, avoiding the requirement to maintain the binder at an elevated temperature prior to mixing.