Abstract: A boiler unit comprises an enclosure including: a first circuit of a first fluid heat exchange medium, the first circuit having a heating device to heat the first medium, a boost heat exchanger, a valve and a first manifold; a second circuit of a second heating system fluid heat exchange medium, the second circuit having a flow and return port of the boiler unit, a second manifold and said boost heat exchanger for exchange of heat between said first and second heat exchanger media when said valve is open; a space in the enclosure receiving an auxiliary unit to be driven substantially exclusively by said first fluid heat exchange medium; and a boiler control unit to control operation of the heating device according to heat demand of the heating device and otherwise irrespective of the auxiliary unit when connected; and an organic rankine cycle (ORC) unit comprising: a third fluid heat exchange medium circuit, the circuit including a condenser adapted for connection to said second manifold to provide heat to sa

Abstract: A waste heat steam generator for a gas and steam turbine power plant is provided. The generator has economizer, evaporator and superheater heating surfaces which form a flow path and through which a flow medium flows. An overflow line branches off from the flow path and leads to injection valves arranged downstream at a flow side of a superheater heating surface in the flow path. The overflow line permits a brief power increase of a downstream steam turbine without resulting in an excessive loss in efficiency of the steam process. The brief power increase is permitted independently of the type of waste heat steam generator. The branch location of the overflow line is arranged upstream of an evaporator heating surface at the flow medium side and downstream of an economizer heating surface.

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 steam generator for producing superheated steam in a waste incineration plant, includes a boiler housing having a combustion chamber with walls having an evaporator. The evaporator has tubes carrying water and being acted upon by heat energy released during incineration of waste, for producing superheated steam. A wall superheater for increasing temperature of the superheated steam includes a plurality of tubes in a wall of the boiler housing for carrying superheated steam being protected against flue gas from an incineration process by plate-like elements formed of a corrosion-proof material. The boiler housing includes an evaporator housing section having the water-carrying tubes and a wall-superheater housing section spatially separated from the evaporator housing section and having the superheated steam-carrying tubes. The wall-superheater housing section is movable relative to and disposed downstream of the evaporator housing section in flue gas flow direction.

Abstract: A small supercritical once-through steam generator (OTSG) includes a radiant section with a furnace coil, and a convection section downstream of the radiant section that includes a superheater which is fluidically connected to the furnace coil. Optionally, the OTSG is devoid of a steam separator. An economizer can also be included downstream of the superheater. Supercritical steam can be generated using the OTSG, for use, among other things, in enhanced oil recovery applications.

Abstract: Disclosed is a coal boiler that makes it possible to reduce the height of the boiler and shorten the period of construction. The coal boiler includes a first furnace in which a combustion gas generated by burning coal and air ascends; a second furnace in which the combustion gas supplied from the first furnace flows downward; and a heat recovery area in which the combustion gas supplied from the second furnace flows upward.

Abstract: The invention relates to a fossil-energy heated continuous steam generator, whereby the at least one combustion chamber, viewed in the flow direction of the hot gases, is divided into at least two throughflow segments, formed by evaporator heating surfaces, whereby the evaporator heating surfaces each comprise steam generation tubes welded to each other in a gastight manner and pressurized in parallel with a flow medium. According to the invention, said generator is suitable for operation with high fresh steam parameters, such as for example, steam temperatures of approximately 700° C., with a simple construction and particularly simple assembly, whereby a throughflow segment, arranged after the first through flow segment, viewed in the direction of flow of the hot gases, forms the first evaporator stage for the flow medium, such that the injection of particularly cold flow medium can occur in the region of maximum heating.

Abstract: A furnace of a boiler for a power plant includes an outer water tube section adapted to receive water from the outside and heat the water into hot water (including steam); and an inner water tube section adapted to receive water from the outside and heat the water into hot water (including steam) while allowing the water to be moved upwardly. The outer water tube section is formed in a shape gradually increasing or substantially uniform in diameter from the bottom toward the middle portion M, and gradually decreasing, increasing and decreasing again in diameter from the middle portion M toward the top, and the inner water tube section is formed in a shape gradually decreasing and increasing in diameter from the bottom toward the middle portion M, and gradually decreasing, increasing and decreasing again in diameter from the middle portion M toward the top.

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 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: A saturated steam generator which is provided with a heat source for heating water to generate saturated steam and which can be small-sized. A saturated steam generator for generating saturated steam by heating water with superheated steam resulting from being superheated in a heat transmission tube (16) inserted into a heat storage tank (10), characterized by the provision of a saturated steam generator tank (12), wherein in the heat storage tank (10), disposed in a heat storage section composed by having a solid heat storage material and a liquid heat storage material filled therein are a heat transmission tube (16) and a heater (44), which heats the solid heat storage material and the liquid heat storage material, it being arranged that superheated steam resulting from passing through the heat transmission tube (16) is used as a heat source to heat stored water (22) so as to generate saturated steam.

Abstract: This invention provides a superheated steam apparatus that is capable of efficiently heating water to generate superheated steam, and to perform a process such as sterilization utilizing this superheated steam while keeping the loss of heating energy to a minimum.

Abstract: A steam generator, in particular a waste-heat steam generator, includes first and second evaporator heating surfaces located in an elongate gas flue for hot gas. A first supply line for feed water is throughflow-connected on an inlet side to the first evaporator heating surface, while the second evaporator heating surface is throughflow-connected on an inlet and an outlet side to a low-pressure drum. The low-pressure drum is provided with a second supply line for feed water. The first supply line has a first treatment point and the second supply line a second treatment point. Each of the treatment points serves for adding and/or extracting chemicals for water treatment, so that each evaporator heating surface can receive only feed water which is conditioned according to regulations applying to that evaporator heating surface. A method for operating the steam generator is also provided.

Abstract: The invention concerns a boiler comprising at least a first heat exchanger (10) with its inlet connected to a water supplying duct (18) and its outlet connected, through a first regulating valve (30) to a steam turbine, either directly, or through a second heat exchanger (12). During the starting phase the regulating valve (30) is closed and as long as the fluid at the first heat exchanger (10) outlet is a mixture of water and steam, all the water is transformed into steam by condensation and the regulating valve (30) is opened only when the fluid at the first evaporator outlet is pure steam.

Abstract: A method and a device for using excess heat of flue gas that is not required for operating a flue gas desulfurization device of a power plant is presented. Before being introduced into the flue gas desulfurization device. The flue gas is guided through preheaters for heating the combustion air and an electrostatic filter. The combustion air preheating step is achieved with two air preheaters, one arranged upstream of the electrostatic filter and one arranged downstream of the electrostatic filter. A partial flue gas stream is branched off at least before the first air preheater arranged upstream of the electrostatic filter. The partial flue gas stream is used to generate steam.

Abstract: A heat recovery steam generator (HRSG) which contains multiple superheater and reheater tube units, each unit including an upper and lower header connected pressure-tightly together by a plurality of vertically-oriented tubes provided in alternate parallel banks, with the tubes of adjacent units being provided in an internested arrangement. Each superheater and reheater unit contains primary straight tubes and secondary bent tubes which are offset from the primary straight tubes in a direction perpendicular to the upper and lower headers and parallel to the direction of hot gas flowing transversely past the internested tubes. The ratio of the number of superheater tubes to reheater tubes in each row of tubes is provided in proportion to the desired heat transfer from the hot combustion gas to the superheated or reheated steam passing through the tubes in the generator assembly.

Abstract: There is provided a waste heat recovery system characterized by a boiler assembly including a heat recovery steam generator through which exhaust gas is flowed. The boiler assembly includes a high temperature steam tube heat exchanger, or superheater, and at a location downstream therefrom a water tube boiler. An ammonia gas injector is utilized for injecting ammonia into the exhaust gas stream which injector is located upstream of the superheater and water tube boiler. Finally, there is provided a low temperature selective catalytic reduction unit located downstream of the low temperature water tube boiler or evaporator. This arrangement simplifies retrofitting of existing heat recovery systems.

Abstract: Waste heat steam generator for hot, dust-loaded gases under overpressure, with a gas feedline, with a gas exhaust line as well as with heat exchanger elements through which a coolant flows. The gas feedline is conducted inside a gas exhaust line, which opens from above into heat exchanger space which is concentrically arranged in a pressure vessel. The heat exchanger space is open at the lower end and in it the heat exchanger elements are supported. The space between the containment walls of the heat exchanger space and the pressure vessel wall at the upper end of the pressure vessel is connected to the gas exhaust line. The pressure vessel bottom in the form of a funnel is connected to an ash removal device. The containment walls of the heat exchanger space are provided with heat exchanger tubes.

Abstract: The steam generator has a combustion chamber which merges at the top into a combustion gas flue having walls in the form of evaporator tubes. A superheater tube bank is suspended in the combustion gas flue in front of the evaporator tubes. The superheater tubes are connected together in pairs to a common inlet at a lower end which passes through the evaporator tube banks while the evaporator tubes of the combustion chamber are connected in pairs to a single evaporator tube within the flue.Retaining elements are provided to form a moving connection between the superheater tubes and the evaporator tube and provision is made to compensate for differences in expansion between the superheater tubes and the evaporator tubes at the top end of the superheater tube bank.

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).

Abstract: A steam flow path arrangement for covering the walls of the rear gas pass of a steam generator. The entire flow passes down the sidewalls with a minor portion then passing up through the rear wall to a superheater inlet header at an intermediate elevation. The major portion of the flow passes up the front wall and through hanger tubes to a roof header. From there the major portion passes across the roof and down the rear wall to the superheater inlet header at the intermediate elevation.