Abstract: A steam generator having a heat transfer tube group formed of a plurality of U-shaped heat transfer tubes; an annular channel formed to cover the circumference of the heat transfer tube group; the annular channel having an opening that communicates with the heat transfer tube group; a water supply unit disposed at an upper portion of the annular channel and supplies water to a descending-side portion; a steam/water separator disposed above the heat transfer tube group; and an air bubble removing member for removing air bubbles provided in the annular channel.

Abstract: A system for generating steam for a turbine of an electric generator includes a superheater that receives steam from a boiler and that superheats the steam. All or a portion of the superheated steam from the superheater is then passed through a heat exchanger to transfer some of the heat energy in the superheated steam to a flow of water. This reduces a temperature of the superheated steam to a temperature that is suitable for the turbine. The water heated in the heat exchanger can be condensed water that has already passed through the turbine, and the water heated in the heat exchanger can be routed to the boiler, where it is re-cycled back into steam.

Abstract: A control system for maintaining a desired heat exchanger outlet flue gas temperature across a range of boiler loads. The heat exchanger includes a plurality of tubular configurations in heat exchange contact with the flue gas with each tubular configuration having a separate feedwater inlet. Flue gas temperature control is achieved by modulating the feedwater flow rates through the tubular configurations. In a system having two tubular configurations, the overall heat transfer capacity of the heat exchanger may be reduced to maintain the desired heat exchanger outlet flue gas temperature by reducing feedwater flow through one tubular configuration and overflowing the other, while maintaining the total flow of feedwater through the heat exchanger substantially constant.

Abstract: A gas temperature control system for maintaining a desired economizer outlet gas temperature across a range of boiler loads comprises a plurality of tubular configurations having surfaces that are in contact with the flue gas. Each tubular configuration, preferably, comprises a plurality of serpentine or stringer tubes arranged horizontally or vertically back and forth within the economizer, and each tubular configuration having a separate feedwater inlet. Heat transfer from the flue gas is accomplished by controlling the feedwater flow rates through the tubular configurations. In a temperature control system having two tubular configurations, the overall heat transfer capacity of the economizer may be reduced to maintain the desired economizer outlet gas temperature during low boiler loads by reducing feedwater flow through one tubular configuration and by overflowing the other tubular configuration, such that total flow of feedwater through the economizer is maintained substantially constant.

Abstract: A boiler for making super heated steam by indirect heat exchange of water against a hot gas, said boiler being a vertically oriented vessel comprising a spirally formed conduit around the vertical axis of the vessel, which vessel is provided with an inlet for hot gas fluidly connected to the lower end of the conduit for upwardly passage of hot gas through the spirally formed conduit, an outlet for cooled gas fluidly connected to the upper end of the conduit, an inlet for fresh water and a vessel outlet for super heated steam, said vessel further provided with a water bath space in the lower end of the vessel and a saturated steam collection space above said water bath space, said spirally formed conduit comprising of a spirally formed evaporating section located in the water bath space and a spirally formed super heater section at the upper end of the vessel, wherein the conduit of the super heater section is surrounded by a second conduit forming an annular space between said super heater conduit and said se

Abstract: The invention relates to an arrangement in a recovery boiler, into which spent liquor to be combusted and combustion air are fed, the arrangement comprising superheaters in the upper part of the recovery boiler for recovering heat. Instead of screen tubes the invention is provided with a superheater formed of horizontal elements.

Abstract: A furnace wall comprises: a furnace wall bottom part composed of furnace wall tubes having upward-spiraled fluid passages; a nose part which has nose wall tubes disposed in a middle part of a furnace rear wall adjoining the furnace wall bottom part; and a screen part having screen tubes, wherein the terminal parts of the furnace wall tubes are located lower than the nose part. Consequently, the drain generated in the nose wall tubes while the operation of the boiler is suspended can naturally fall inside the furnace wall tubes located lower than the nose part, and in a case where the header is connected with the terminal parts of the furnace wall tubes, the drain generated in the nose wall tubes can naturally fall inside the header.

Abstract: The invention relates to a method and a steam generator for generating steam, in particular ultrapure steam, by reacting a stoichiometric mixture comprising a fuel, in particular hydrogen, and an oxidizing agent, in particular oxygen, and injecting water into the hot reaction gases, which is distinguished by a high purity of the steam generated.

Abstract: A method for positioning superheaters (2, 3, 4, 5) in biomass burning steam generators, and a steam generator. The steam generator comprises a combustion chamber (1), a flue gas duct (6), a steam circuit (7), and the superheaters (2, 3, 4, 5) positioned for minimizing corrosion at a high temperature. The steam generator is fitted with at least two superheaters (2, 3, 4, 5), whose positioning in the flue gas duct (6) and serial arrangement in the steam circuit (7) are effected in such a way that the superheater's or superheaters' heat transfer surface has its surface temperature remaining below the melting point of KOH, 406° C. (corresponds to a steam temperature of about 350-380° C.) down to the point in the flue gas duct (6), at which the flue gases' temperature has fallen to 750° C. While the flue gases are within the range of less than 750° C.

Abstract: A continuous flow steam generator with a double-flue construction has a vertical gas flue with an ascending conduction of fuel gas. The combustion chamber rear wall is inclined inwards and towards the combustion chamber in an upper part region and thereby forms, with the bottom of an adjoining horizontal gas flue, a nose which projects into the combustion chamber. Some steam generator tubes of the lower part region of the combustion chamber rear wall are led upwards, uninclined, as supports for the combustion chamber rear wall, as far as a supporting structure located outside the conduction of the fuel gas.

Abstract: A system for maintaining an optimal flue gas inlet to a boiler mounted SCR assembly in the flue of the boiler is accomplished by mixing the normal inlet feedwater to an economizer of the boiler with near saturation water from downcomers of the boiler to thereby raise the temperature of the flue gas passing across the economizer and raising the SCR inlet to the desired optimal SCR operation temperature.

Abstract: An exhaust heat recovery boiler in which an exhaust gas discharged from a gas turbine into a boiler duct to recover a heat of the exhaust gas and ammonia is injected to and mixed with the exhaust gas to reduce nitrogen oxide contained in the exhaust gas, the exhaust heat recovery boiler comprising: a boiler duct of a horizontal installation type having an inner hollow portion along which an exhaust gas flows from an upstream side to a downstream side; a superheater; an evaporator; a denitration reactor; and an economizer, which are disposed inside the boiler duct in this order from the upstream side to the downstream side of the exhaust gas flow therein. A drum is disposed outside the boiler duct and connected to the evaporator and a downcomer pipe extending from the drum into the boiler duct.

Abstract: The steam generator comprises a cylindrical outer jacket (2) arranged with its axis vertical, a bundle wrapper (4) arranged coaxially with respect to the outer jacket and a space (9) in which feed water can flow between the bundle wrapper (4) and the outer jacket (2) or a guide skirt (8, 8a). A water supply device (10) placed towards the top of the space (9) in which the feedwater flows comprises a torus-shaped manifold (12), the upper wall of which is traversed by a number of flow openings (18) distributed in the circumferential direction of the manifold (12). A feed pipe (13) opens into the manifold and the feedwater is guided by a guide device towards the annular flow space (9). Radial dividing walls (19a, 19b, 19c, 19d) are arranged transversely in a water flow space delimited between the manifold (12) and the guide device (14).

Abstract: A bundled-tube heat exchanger of the vertical arrangement type has a gas inlet chamber and a gas outlet chamber. These gas chambers are connected by gas transfer tubes. The gas transfer tubes are surrounded by cooling medium tubes within a housing chamber. Each of the cooling medium tubes opens out into a respective connecting chamber that is formed between the casing chamber, the gas inlet chamber, and the gas outlet chamber. A gas transfer tube that is open to the casing chamber connects the casing chamber to a connecting chamber.

Abstract: A steam generating heat exchanger (2) for cooling a high pressure, hot gas laden with molten ash particles comprising an inverted U-shaped pressure containment structure (4,6,8) having various heat exchange means disposed therein. The heat exchanger is formed of a first vertically elongated cylindrical pressure containment vessel (4) housing a radiant cooling chamber (12) therein, a second vertically elongated cylindrical pressure containment vessel (6) housing a convective cooling chamber (30) therein, and a pressure containment pipe (8) connecting the second pressure containment vessel (6) to the first pressure containment vessel (4) and housing therein a water-cooled duct (26) connecting the gas outlet of the radiant cooling chamber (12) disposed within the first pressure containment vessel (4) to the gas inlet of the convective cooling chamber (30) disposed within the second pressure containment vessel (6).