Abstract: An electric boiler includes a conductivity control having a controller responsive to both steam pressure and electrode current. The controller is operative to open a boiler feed water discharge valve when either the steam pressure or electrode current falls below predetermined values to discharge water from the boiler for a predetermined time interval after which the controller closes the discharge valve and opens a feed water valve to initiate the delivery of feed water to the boiler chamber. When the pressure or current sensor senses the elevation of steam pressure or electrode current to second preselected levels the controller closes the feed water valve. In addition, if the sensors determine that the steam pressure or electrode current have risen to third preselective levels, a transfer valve is opened to transfer boiler water to a storage tank until the pressure or current level falls to fourth preselected levels.

Abstract: Removal of concentrated suspended particulate material from the recirculating carry-over water in a nuclear steam generator is provided by establishing a mud drum or reservoir of relatively quiescent water, permitting the concentrated solids contained therein to settle out prior to returning the water for mixing with the feedwater. Baffles in the mud drum intercept the entering carry-over water in a manner such that only a small portion of it is exchanged by the newly entering water so that, for the most part, there is sufficient residence time in a relatively quiescent environment to settle out the solids.

Abstract: A steam generator includes a tank with a water inlet valve, a steam outlet, an electric immersion heater in said tank, and a normally closed drain valve. A water level control, connected to the inlet valve and the heater, is arranged to apply power to the heater only when it is immersed, and to admit make up water into the tank as steam is used. A drain valve control is connected to said drain valve and operates to open the drain valve to flush the tank only upon starting the generator after completion of a generator cooling period sufficient to condense residual steam in the tank which follows shut down of the generator. The completion of such a cooling period is sensed by either a pressure sensitive or a temperature sensitive switch which responds to conditions in the generator. The switch is connected to the drain valve control to prevent opening of that valve should the generator not be cooled to ambient temperature.

Abstract: An apparatus and method for automatically blowing down a boiler are disclosed, wherein the discharged sediment-containing water is drawn off to an intermediate receiver or holding tank for a short interval and then sent through a heat exchanger which is isolated for the boiler. The condition of the water in the boiler is continuously monitored by conductivity sensors to begin each blowdown cycle when the conductivity reaches a predetermined level. A three-way valve connected to the bottom blowdown line of the boiler is opened automatically and the blowdown water is forced out of the boiler under the steam pressure to the receiver and sent by means of the same valve to a heat exchanger. This is accomplished by allowing steam from the boiler to enter the receiver to displace the blowdown water, and sweep non-condensibles therefrom.

Abstract: A method for removing sludge that may be deposited on a tubesheet of a steam generator comprises placement of fluid headers at the elevation of the sludge to be removed establishing a circumferential fluid stream at that elevation. A fluid lance is moved along the line between the headers emitting a pulsating fluid jet perpendicular to a line of movement of the fluid lance at an elevation substantially corresponding to the level of sludge deposits. The fluid jet forces the sludge to the periphery of the tubesheet where the sludge is entrained in and carried away by the circumferential fluid stream.

Abstract: Apparatus for removing sludge that may be deposited on a tubesheet of a steam generator comprises fluid headers at the elevation of the sludge to be removed for establishing a circumferential fluid stream at that elevation. A fluid lance is also provided for being moved along the line between the headers emitting a pulsating fluid jet perpendicular to a line of movement of the fluid lance at an elevation substantially corresponding to the level of sludge deposits. The fluid jet forces the sludge to the periphery of the tubesheet where the sludge is entrained in and carried away by the circumferential fluid stream.

Abstract: An electrode steam boiler includes a water-receiving shell and water-heating electrodes supported in the shell so as to be partially immersed in the water to be heated. The boiler also has first and second water-handling means arranged, respectively, for supplying feed water to, and withdrawing water from, the boiler shell, and a current responsive means responsive to the current flowing in one of the electrodes for actuating the two water-handling means. Finally, the boiler has means for monitoring the number of actuations in a pre-set period of at least one of the two water-handling means, and means responsive to this monitoring means for actuating a safety means when this number of actuations in a pre-set period of at least one of the water-handling means exceeds a predetermined value. The safety means may take the form of an audible and/or visual alarm or a device for shutting down the boiler.

Abstract: A tube heat exchanger having a substantially cylindrical housing, a pair of adjacent cylindrical headers disposed in the housing, and a multiplicity of downwardly extending U-shaped heat exchanger tubes connecting the headers to one another, one of the headers being an inlet header and the other thereof being an outlet header, both of the headers being connectible to pressurized water lines of a pressurized water nuclear reactor, includes a feedwater supply connected to the housing below the outlet header for supplying a quantity of feedwater into the housing up to a given level partly filling the housing during operation of the heat exchanger, the heat exchanger tubes extending upwardly from the outlet header above the given feedwater level and being formed with a U-shaped bend located above the given level.

Abstract: A vapor generating unit having a U-shaped tube bundle is provided with an orificed downcomer shroud and a fluid flow distribution plate between the lower hot and cold leg regions to promote fluid entrained sediment deposition in proximity to an apertured blowdown pipe.

Abstract: A system for removing sludge that may be deposited on a tube sheet of a steam generator. Headers are arranged at the elevation of the sludge to be removed establishing a circumferential fluid stream at that elevation. A fluid lance is moved along the line between the headers emitting a fluid jet perpendicular to the line of movement of the fluid lance at an elevation substantially corresponding to the level of sludge deposits. The fluid jet forces the sludge to the periphery of the tube sheet where the sludge is entrained in and carried away by the circumferential fluid stream.

Abstract: A combined timer, blow down warning device, chemical pump, and controller for boilers. The circuit comprises an electro-mechanical array of relays, flashing lights and alarms and an electronic tripper which operates from the rate of change in temperature in the blow down tailpipe, to turn off the lights and alarms only after a manual blow down operation has been performed.

Abstract: A system of heat exchangers for cooling process fluids. The system is particularly applicable to cooling steam generator blowdown fluid in a nuclear plant prior to chemical purification of the fluid in which it minimizes the potential of boiling of the plant cooling water which cools the blowdown fluid.

Abstract: A steam generator having a U-shaped tube bundle which extends upwardly from a tube sheet, a wrapper encircling the tube bundle, a preheater disposed on the cold leg portion of the tube bundle and a distribution plate disposed adjacent the tube sheet, the distribution plate having a large semicircular shaped opening disposed in the central portion of the hot leg and a T-shaped blowdown pipe disposed so that the cross of the "T" is disposed adjacent the tube sheet and the central portion of the semicircular opening in the distribution plate.