Abstract:
A steam generator including a steam chamber defining an enclosed fluid chamber with a plurality of tubes passing through the steam chamber, a combustion chamber defining a closed fluid chamber and an air channel coupled to a burner, and a heat transfer section defining a closed fluid chamber and an air passage in fluid communication with a vacuum source, in which the burner generates a heated air mixture, the vacuum source draws the heated air mixture from the combustion chamber air channel, through the steam chamber plurality of tubes and through the heat transfer section air passage so as to heat fluid passing through the heat transfer section, the steam chamber and the combustion chamber fluid chamber.
Abstract:
A boiler (1) for heating water to steam comprises a boiler housing (10) having a bottom wall (12), a top wall (13) and a circumferential wall (14) extending between these walls (12, 13). When the boiler (1) is mounted in a steam generating device for generating steam and supplying steam to an appliance such as a steam iron (20), the boiler (1) is given an inclined orientation. In a lower portion (13a) of the top wall (13) of the boiler housing (10), an inlet opening (15) for letting in water to a boiler space (11) which is enclosed by the boiler housing (10) is arranged. When water is supplied through the inlet opening (15), the water lands on a lower zone (14a) of the circumferential wall (14) and flows further in a downward direction, along the circumferential wall (14). As a result, the water is pre-heated when it reaches the water which is already present in the boiler space (11), and there is no danger of the steam production getting interrupted.
Abstract:
A low liquid level sensor in a hot water heating system permitting testing operability thereof in situ without draining down the system. The sensor is located in a cavity that has an opening in the bottom thereof in fluid communication with the liquid in the vessel during normal operation of the system. The end of the opening is at a lower elevation than the sensor and liquid from the vessel is in the cavity during normal operation of the system. When the liquid drops to a predetermined low level the sensor activates the safety cut-off. Valved passed means are provided exteriorly of the vessel so that a gas can be injected into the cavity to pressurize the same and drive the liquid in the cavity through the opening into the vessel simulating a low water level condition. At the simulated low water level condition operability of the sensor can be determined. Means are provided to release the gas from the cavity. The sensor is mounted by an insulator that projects into the cavity and the gas release means is spaced from the end of the cavity so that an air pocket is maintained reducing the tendency of conductive deposits to build up on the insulator. A fail safe circuit is provided avoiding malfunctioning of the cut-off safety control should there be a large build up of conductive deposits on the insulator.
Abstract:
A system and process is provided for controlling a steam generation and distribution system including a plurality of headers. Each of the headers is coupled to steam using devices such as steam turbines and steam supplying devices such as boilers. The process includes measuring the pressure at each header and when the pressure changes, identifying each path beginning at the particular header and terminating at a boiler, and determining the alteration of a boiler and any particular steam turbines required to restore the required pressure at the header while doing so at the least incremental cost.
Abstract:
A system includes the HRSG having an economizer disposed along a fluid flow path, and a drum disposed along the fluid flow path downstream of the economizer. The HRSG also includes a drum level control module configured to modulate an amount of the fluid provided to the drum along the fluid flow path and a supplemental control module configured to control an amount of the fluid in a different manner than the drum level control module. The heat recovery steam generator also includes a drum level event controller configured to monitor a rate of change of a level of the fluid in the drum. If the rate of change is over a threshold value, a signal goes to the supplemental control. If the rate of change is less than or equal to the threshold value, the signal goes to the drum level control module.
Abstract:
Aqueous working fluid (WF) steam generation system including: pressure vessel containing heat exchanger; enclosed combustion air (CA) chamber; burner; another heat exchanger outside pressure vessel; and WF conduit. Heat exchanger includes first: enclosed WF chamber having WF input and output apertures (IOA); and enclosed CA passageway communicating with CAIOA and passing through enclosed WF chamber. Enclosed CA chamber includes second: enclosed WF chamber having WFIOA; and enclosed CA passageway communicating with CAIOA. Burner is connected to second CA input aperture. Another heat exchanger includes third: enclosed WF chamber having WFIOA; and enclosed CA passageway communicating with CAIOA. WF conduit connects third WF output aperture to second WF input aperture. Second WF output aperture is connected to first WF input aperture; and second CA output aperture is connected to first CA input aperture; and first CA output aperture is connected to third CA input aperture.
Abstract:
A steam generator boiler for generating steam is connected to a supply conduit for supplying water to the boiler with a supply valve for controlling the supply of water through the supply conduit. A heater supplies heat to the boiler for generating steam with a discharge conduit for discharging excess impure water therefrom. A metering device is operatively connected to the supply conduit for regulating the flow of water to the boiler by calculating the amount of water required based on wattage or BTU's generated by the heater. A pressure switch or thermostat is provided for operating the boiler and the supply valve on the supply conduit for supplying water to the boiler to permit water to be added every time the heater is energized. In addition, a heat exchanger is provided for receiving discharged heated water from the steam generator and preheating water supplied to the steam generator.
Abstract:
A control for a water heater is provided that comprises a pressure switch for sensing a predetermined level of airflow sufficient for maintaining proper burner operation, and a temperature sensing means for sensing the temperature of the water in the tank. The control further comprises a processor for controlling the operation of the burner to maintain the water temperature above a predetermined value. When the processor receives a signal from the pressure switch indicating an insufficient level of airflow, the processor shuts down the burner and subsequently attempts to restart the burner. The processor will also lock-out further burner operation after a predetermined number of consecutive shut downs occurs before the water is heated to a desired temperature during a single call for heating.
Abstract:
A feedwater control system considering a pressure drop of feedwater control valve in a nuclear power plant and a control method therefor are provided. In the feedwater control system, a first detection unit includes: a flow error signal generator for generating a flow error signal corresponding to a difference between a steam flow signal and a feedwater flow signal; and a water level correction error signal generator for generating a water level correction error signal corresponding to a sum of a water level measurement signal and the flow error signal. A second detection unit includes: a pressure drop sensor unit for detecting a pressure difference between front and rear portions of at least one feedwater control valve among the main feedwater control valves and the downcorner feedwater control valves and generating a pressure drop signal corresponding to the detected pressure difference; a pressure drop setup value signal generator for generating a pressure drop setup value signal corresponding to a previously set pressure drop setup value of the feedwater control valves; and a pressure drop error signal generator for comparing the pressure drop signal with the pressure drop setup value signal and generating a pressure drop error signal. A control unit controls the main feedwater pump based on a correction control signal output from the correction control signal generator.