Abstract:
A corrosion and hydride resistant nuclear fuel rod having a highly corrosion resistant outer portion in which hydride precipitation is inhibited and an inner portion in which hydride precipitation is promoted.
Abstract:
A process for recovering uranium from a waste sludge involves treating the sludge with a non-reactive, non-absorptive cellulose filtration media, adding an oxidant and heating the mixture to dissolve any uranium present. The mixture is passed through a filtration device precoated with the same filtration media, where the solids are captured while the dissolved uranium passes through as part of the filtrate, for recovery.
Abstract:
A nuclear fuel pellet having concentric layers of nuclear fuel in which an outer layer has less fissionable nuclear fuel per unit volume and substantially the same amount of fertile material per unit volume as an inner core.
Abstract:
Zirconium alloys for use in an aqueous environment subject to high fluence of a water reactor and characterized by improved corrosion resistance, consisting essentially of 0.3 to 1.8 weight percent tin, 0.1 to 0.65 weight percent iron, the balance of alloys being essentially nuclear grade zirconium with incidental impurities and having a microstructure of Zr.sub.3 Fe second phase precipitates distributed uniformly intragranularly and intergranularly to form radiation resistant second phase precipitates in the alloy matrix.
Abstract:
An apparatus for measuring fuel assembly bow and twist comprising a fixturing apparatus, a reference device and an ultrasonic measuring device.
Abstract:
A method and apparatus is disclosed for converting a reheat steam turbine plant to a non-reheat, combined cycle plant without requiring internal modification of the steam turbine unit. A reheat steam turbine power plant with a boiler and a steam turbine with a plurality of turbine sections, receiving steam under pressure and successively expanding the steam through the turbine sections, is converted to a non-reheat combined cycle plant by replacing the boiler with a dual-pressure heat recovery steam generator capable of producing main steam and secondary steam at differential temperature and pressure and by installing a trimming system to allow adjustment of the pressure drop between the exhaust of the first turbine section and the inlet of the second turbine section to prevent damage to the turbine blades. The non-reheat cycle plant may also be operated with secondary steam supplied at the inlet of the final turbine section to reduce the moisture content of the steam thereby preventing excessive wear on the turbine blades.
Abstract:
A nuclear fuel assembly for a boiling water reactor having a spacer grid for positioning and retaining the fuel rods. The spacer grid comprising an upper grid structure and a lower grid structure. Each grid structure comprises a first set of grid strips and a second set of grid strips which intersect to form in each grid structure a lattice of rectangular and square shaped cells through which the fuel rods extend and which act against the fuel rods within the cells. The lattice in each of the upper grid structure and the lower grid structure being the same. The upper grid structure and the lower grid structure being oriented relative to one another so that each of the rectangular and square shaped cells in the upper grid structure is superimposed on a corresponding one of the rectangular and square shaped cells in the lower grid structure so as to act cooperatively against and provide support to a fuel rod on four sides of the fuel rod.
Abstract:
An improved fuel rod is provided having a part-length fuel rod portion that improves performance with respect to typical part-length fuel rods without significant degradation of the benefits that are achieved by using such a system, e.g., improved fuel utilization, stability, and shut down margin. The present invention provides a fuel rod for a light water nuclear reactors that comprises a part-length fuel rod and an extension tube having at least one wall member defining an enclosed flow path therethrough, the extension tube being coupled to a portion of the part-length fuel rod so as to be disposed axially above the part-length fuel rod, and including at least one inlet opening, for allowing fluid that surrounds the rod and initially comprises a two phase mixture of steam and liquid, to enter the enclosed fluid path and at least one outlet opening located above the inlet opening, the extension tube includes means for separating at least some of the steam located in the fluid from the liquid located therein. The improved fuel rod allows steam to bypass the upper active portions of the fuel assembly. A nuclear fuel rod for a light water reactor having a part length fuel rod and a reflex upper end fitting which functions to separate the liquid and vapor steam portions of two phase flow.