Abstract:
A self-sampling corrosion monitor is structurally adapted to be connected to the blowdown system or other piping systems external to the steam generator (14). The monitor includes a pump (24) for providing positive solvent flow through the monitor, and a regenerative heat exchanger (30) using recovered heat at the outlet. Magnetite (44) is also added to a sludge cup within the corrosion monitor vessel (40) to simulate real time measurement of short-lived corrosion conditions in the steam generator. In addition, the available equipment is modified to provide automatic microprocessor-controlled range selection. Still further, data acquisition, storage, and display techniques are modified.
Abstract:
Control system (60) particularly suited for effecting control over an integrated gasification combined cycle system (IGCC) (62) that includes at least a fuel feed system (64), a gasifier system (10), a product gas cleanup system (66), a booster compressor (68) and a gas turbine (70). The subject control system (60) includes a bleed air control valve (96), a booster compressor bypass control valve (98), a fuel feed control valve (100) and a product gas shutoff valve (102). The bleed air control valve (96), which is connected in fluid flow relation between the gas turbine (70) and the booster compressor (68) of the IGCC (62), is operable for effecting control over the amount of air that is bled in the IGCC (62). The booster compressor bypass control valve (98), which is connected in fluid flow relation between the upstream side and the downstream side of the IGCC (62), is operable for effecting the bypass of air around the booster compressor (68) of the IGCC (62). The fuel feed control valve (100), which is connected in fluid flow relation between the fuel feed system (64) and the gasifier system (10) of the IGCC (62), is operable for effecting control over the amount of fuel that is fed from the fuel feed system (64) of the IGCC (62). The product gas shutoff valve (102), which is connected in fluid flow relation between the product gas cleanup system (66) and the gas turbine (70) of the IGCC (62), is operable for shutting off the flow of product gas to the gas turbine (70) of the IGCC (62).
Abstract:
A stabilized alpha metal matrix provides an improved ductility, creep strength, and corrosion resistance against irradiation in a zirconium alloy containing on a weight percentage basis tin in a range of 0.4 to 1.0 percent and typically 0.5; iron in a range of 0.3 to 0.6 percent, and typically 0.46 percent; chromium in a range of 0.2 to 0.4 percent, and typically 0.23 percent; silicon in a range of 50 to 200 ppm, and typically 100 ppm; and oxygen in a range of 1200 to 2500 ppm, typically 1800 to 2200 ppm. The high oxygen level assists in reducing hydrogen uptake of the alloy compared to Zircaloy-4, for example.
Abstract:
A high performance, multi-stage, pressurized, airblown, entrained flow coal gasifier system (10) and a method of operating such a gasifier system (10) for generating therewithin fuel gas from coal. The subject gasifier system (10) includes an outer, pressure containing vessel (14) surrounding an inner, water-cooled vessel (12) wherein the gasification reaction, through which the fuel gas is generated from coal, takes place. The inner, water-cooled vessel (12) embodies a first stage (22) within which the high temperatures required for the gasification reactions to take place as well as for slagging are generated from the combustion of char, a second stage (24) within which the char is gasified to generate the subject fuel gas, and a third stage (26) within which coal is devolatilized to produce the char for the first stage (22) and the second stage (24) and with a concomitant quenching being effected of the fuel gas as the latter flows through the third stage (26) of the inner water-cooled vessel (12).
Abstract:
A method for generating an on-line trip signal when a measured one (p1') of a plurality of operating parameters (p1, p2, p3, ...pN) which define a limit surface on a multidimensional reactor operating space, exceeds a limit value (*p1) on the limit surface. The method includes the steps of storing in an array having at least three dimensions, a set of discrete limit surface values *p1(r) of parameter p1 in ordered triplets, [*p1(r), p2(r) and p3(r)] under reference conditions in which parameters p2 and p3 vary discrtely and parameters p4 ...pN are deemed constant. While operating the reactor, the on-line values p1', p2', p3' of the parameters p1, p2 and p3 are measured. An interpolation is made among the selected triplets to estimate the surface limit value *p1' corresponding to the measured values of p2' and p3'. Preferably, the method includes measuring the operating parameters p4, p5 to obtain values p4' and p5'. The storage means includes a second array defining a quantitative relationship among the values in triplets [*p1(a), p4(a), and p5(a)]. The estimated value of *p1' is then adjusted by the step of interpolating between values of p4(a) and p5(a) based on the measured values p4', p5' to arrive at an adjsuted estimate of the power, *p = *p1' + *p1'(a) or *p1 = (*p1')(*p1'(a)).
Abstract:
A plurality of neutron flux sensors (44, 46, 48, 50) and a corresponding plurality of gamma flux sensors (62, 64, 66, 68) are distributed throughout axial zones (24, 26, 28, 30) of the core (14) at the same or closely proximate locations. A steady state comparison, or bias, between the signals of a given neutron/gamma sensor pair are monitored (314, 316), and a divergence (or convergence) can readily be detected through simple signal filtering, to detect a shift in the bias. The pattern of significant convergence and divergence throughout the core, is indicative of the thermal hydraulic stability of the core.
Abstract:
The displacement of a valve stem (16) is measured during diagnostic testing by temporarily mounting a laser head (112) on the valve body (18) or yoke (20), for generating a source laser beam (118) that reflects from a target (120) that moves with the stem. The timing of the reflected beam (132) returning to the head (112) relative to the projection of the source beam, gives an indication of the displacement of the stem.
Abstract:
An apparatus (10) for measuring an outside diameter of a cylindrical object moving along an axis (14) includes a plurality of fixed transducer pairs (12a-12h) for providing a continuous outside diameter profile of the moving cylindrical object. The sensors (12) are located in a holder (18) enveloping the cylindrical object. Temperature compensation for changes in temperature in the coupling medium include a wire reflector (50) in an ultrasonic path at a fixed distance from a face of the sensor (12). Various types of outputs, including a continuous profile of the cylindrical object are provided. A method of measuring the outside diameter of such cylindrical objects while moving is also disclosed.
Abstract:
An advanced control room complex for a nuclear power plant, including a discrete indicator and alarm system (72) which is nuclear qualified for rapid response to changes in plant parameters and a component control system (64) which together provide a discrete monitoring and control capability at a panel (14-22, 26, 28) in the control room (10). A separate data processing system (70), which need not be nuclear qualified, provides integrated and overview information to the control room and to each panel, through CRTs (84) and a large, overhead integrated process status overview board (24). The discrete indicator and alarm system (72) and the data processing system (70) receive inputs from common plant sensors and validate the sensor outputs to arrive at a representative value of the parameter for use by the operator during both normal and accident conditions, thereby avoiding the need for him to assimilate data from each sensor individually. The integrated process status board (24) is at the apex of an information hierarchy that extends through four levels and provides access at each panel to the full display hierarchy. The control room panels are preferably of a modular construction, permitting the definition of inputs and outputs, the man machine interface, and the plant specific algorithms, to proceed in parallel with the fabrication of the panels, the installation of the equipment and the generic testing thereof.
Abstract:
A tamper-proof closure (10) is inserted by means of positioning tool (20) into a nuclear fuel consolidation storage canister (30). The closure (10) includes a grooved weakened portion (44), which if it exceeds its elastic limit when the base (12) is flexed during removal attempts will indicate any attempts to remove or otherwise tamper with the thus closed canister. Locking tabs (18), on transverse legs (13 and 14) extending from base (12) are engaged in slots (40) in the wall of the opening of canister (30) when the closure (10) is in fuel storage position. Tool (20) has a portion (46) which enters a slot (48) in base (12) at 90° to its working position and then twists to engage spanning portion (42's) flanges (43) in slots of flanges (16) on the legs (13) and (14) to retract tabs (18). The base is prevented from flexing on insertion into the container opening by support it receives from portion (46).