Abstract: An inlet air filter arrangement for a gas turbine or a combustion turbine includes a housing with an inlet side and an outlet side separated by a planar tubesheet including multiple tubesheet openings. Each multiple cylindrical filter cartridge includes a symmetry axis, an open end, and a closed end. A connection assembly for each of the multiple cylindrical filter cartridges seals the open end of the cylindrical filter cartridge to the tubesheet around one of the tubesheet openings. The connection assembly includes a mainly cylindrical guide sleeve including a symmetry axis, a shell with a cylindrical external surface, an inner end attached around the tubesheet opening and an outer end at the inlet side of the housing. The shell is provided with at least two slots extending mainly helically from the outer end towards the inner end. A collar attaches to the open end of the cylindrical filter cartridge.

Abstract: A grid nozzle assembly for a fluidized bed reactor that includes a horizontally extending bottom plate, a gas plenum chamber below the bottom plate, and vertical gas pipes having a top end and extending from the gas plenum chamber upwards across the bottom plate. The assembly includes a nozzle head with a gas channel that injects fluidizing gas from one of the vertical gas pipes to the reaction chamber. A tube sleeve is adapted to be fixed by welding around the top end of the vertical gas pipe. The nozzle head and the tube sleeve have a knob and groove portion that form a twist-lock enabling quick connecting and disconnecting of the nozzle head and the tube sleeve.

Abstract: A grid nozzle assembly for a fluidized bed reactor, a fluidized bed reactor with a grid nozzle assembly, a method of mounting a grid nozzle assembly as a replacement in a fluidized bed reactor, and a method of replacing a grid nozzle assembly in a fluidized bed reactor. The reactor includes a horizontally extending bottom plate, a gas plenum chamber below the bottom plate, and vertical gas pipes having a top end and extending from the gas plenum chamber upwards across the bottom plate. The nozzle assembly includes a nozzle head with a gas channel for injecting fluidizing gas from one of the vertical gas pipes to the reaction chamber and a tube sleeve adapted to be firmly fixed by welding around the top end of the vertical gas pipe. The nozzle head and the tube sleeve form a twist-lock enabling quick connecting and disconnecting.

Abstract: A pulse cleaning filter system has a housing with an inlet side and an outlet side separated by a planar tubesheet. The housing includes multiple tubesheet openings forming multiple rows. Multiple cylindrical filter cartridges have an open end sealed around one of the tubesheet openings and a closed end at the inlet side of the housing. A filter cleaning system includes a compressed gas header extending perpendicular to a normal of the tubesheet, multiple compressed gas outlet stub pipes extending from the header, right angle pulse valves connecting each of the stub pipes to a pulse manifold pipe including a first straight portion, a ninety degree bend at the outlet side of the housing, and a second straight portion at the outlet side of the housing. A gas pulse nozzle has a main injection axis directed along the central axis of the filter cartridge.

Abstract: A method of controlling a boiler plant during a switchover period from an air-combustion mode to an oxygen-combustion mode. The method includes steps of feeding fuel into a furnace of the boiler plant at a rate determined by a fuel feeding scheme, feeding air into the furnace at a rate determined by a descending air feeding scheme, feeding substantially pure oxygen into the furnace at a rate determined by an ascending oxygen feeding scheme, and recirculating flue gas into the furnace at a rate determined by an ascending flue gas recirculating scheme. The fuel feeding scheme, the air feeding scheme and the oxygen feeding scheme are such that the fuel is combusted and the flue gas containing residual oxygen is produced. Also, the fuel feeding scheme, the air feeding scheme and the oxygen feeding scheme are such that the content of residual oxygen in the flue gas is, during at least a portion of the switchover period, greater than during any of the air-combustion mode and the oxygen-combustion mode.

Abstract: A solar heat receiver system includes multiple vertically extending solar heat receiving tubes for transferring solar heat to a heat transfer medium flowing through the solar heat receiving tubes, a rigid support structure, two first connectors to connect two spaced-apart portions of the solar heat receiving tubes to the rigid support structure so as to prevent horizontal movement of the two spaced-apart portions of the solar heat receiving tubes, and a second connector for connecting at least one intermediate portion of the solar heat receiving tubes to the rigid support structure, which intermediate portion is located between the spaced-apart portions. The second connector allows a limited amount of horizontal movement of the at least one intermediate portion of the solar heat receiving tubes due to a thermally induced bow of the solar heat receiving tubes.

Abstract: A radiant superheater arranged to hang at the upper portion of a furnace of a boiler. The radiant superheater is substantially planar and includes a first vertical pass, a first connection pass, a second vertical pass, a third vertical pass, a second connection pass, and a fourth vertical pass. Each vertical pass includes an upper end and a lower end.

Abstract: A method of selective catalytic NOX reduction in a power boiler and a power boiler with selective catalytic NOX reduction. Fuel is combusted in a furnace of the boiler and a flue gas stream that includes NOX is generated. The flue gas stream is conducted from the furnace along a flue gas channel to a stack. The flue gas stream is cooled in a heat recovery area, including an economizer section, arranged in the flue gas channel. At least a portion of the NOX is reduced to N2 in an NOX catalyst arranged in the flue gas channel downstream of the economizer section. The flue gas is further cooled and heated air is generated in a gas-to-air heater arranged in the flue gas channel downstream of the economizer section and upstream of the NOX catalyst.

Abstract: A method of providing a weld overlay structure on a heat transfer tube or a membrane surface. A first continuous bead portion of an overlay material is applied onto the heat transfer tube or membrane surface by using a weld head to melt the overlay material. A second continuous bead portion of the overlay material is applied onto the heat transfer tube or membrane surface by using a weld head to melt the overlay material, in which the second bead portion partially overlaps with the first bead portion, forming a groove between the first bead portion and the second bead portion. A third continuous bead portion of an overlay material is applied onto the heat transfer tube or membrane surface by using a weld head to melt the overlay material into the groove between the first bead portion and the second bead portion, so as to form a relatively smooth surface.

Abstract: A method of desulfurizing flue gas in connection with oxy-combustion. A sulfur containing gas flow is introduced to a flue gas desulfurization arrangement having a spray tower at its top part and a reaction tank at its bottom part, in which the reaction tank contains liquid slurry having a surface level L. Sorbent-containing liquid slurry is sprayed to the sulfur containing gas flow. Sulfur-containing molecules are allowed to be absorbed into liquid slurry droplets. The liquid slurry droplets are allowed to enter the liquid slurry in the reaction tank. Oxygen containing gas is bubbled in the liquid slurry from a gas inlet header and nozzles in the reaction tank, in which the nozzles are arranged at a certain level in the reaction tank. Sulfur-containing particulates settle in the reaction tank.

Abstract: A method of selective catalytic NOX reduction in a power boiler and a power boiler with selective catalytic NOX reduction. Fuel is combusted in a furnace of the boiler and a flue gas stream that includes NOX is generated. The flue gas stream is conducted from the furnace along a flue gas channel to a stack. The flue gas stream is cooled in a heat recovery area, including an economizer section, arranged in the flue gas channel. At least a portion of the NOX is reduced to N2 in an NOX catalyst arranged in the flue gas channel downstream of the economizer section. The flue gas is further cooled, and heated air is generated in a gas-to-air heater arranged in the flue gas channel downstream of the economizer section and upstream of the NOX catalyst. The gas-to-air heater may be a tubular air heater or a heat exchanger with a recirculating heat transfer fluid.

Abstract: A method of and a system for combusting fuel in an oxyfuel combustion boiler. Fuel is fed to a furnace of the boiler. Oxidant gas that includes a mixture of substantially pure oxygen and recycled flue gas is fed to the furnace, prior to the feeding of the oxidant gas. At least a portion of the oxidant gas is preheated to generate preheated oxidant gas. The fuel is combusted with the oxidant gas in the furnace so as to generate steam and to produce the flue gas, and at least a portion of the steam is superheated to generate superheated steam. The preheating of the at least a portion of the oxidant gas is performed by using a heat exchanger that transfers heat from a portion of the superheated steam to the oxidant gas.

Abstract: A method of controlling a boiler plant during a switchover period from an air-combustion mode to an oxygen-combustion mode. The method includes steps of feeding fuel into a furnace of the boiler plant at a rate determined by a fuel feeding scheme, feeding air into the furnace at a rate determined by a descending air feeding scheme, feeding substantially pure oxygen into the furnace at a rate determined by an ascending oxygen feeding scheme, and recirculating flue gas into the furnace at a rate determined by an ascending flue gas recirculating scheme. The fuel feeding scheme, the air feeding scheme and the oxygen feeding scheme are such that the fuel is combusted and the flue gas containing residual oxygen is produced. Also, the fuel feeding scheme, the air feeding scheme and the oxygen feeding scheme are such that the content of residual oxygen in the flue gas is, during at least a portion of the switchover period, greater than during any of the air-combustion mode and the oxygen-combustion mode.

Abstract: A circulating fluidized bed combustor arrangement includes (a) a circulating fluidized bed reactor in which (i) a combustion chamber combusts a fuel material in a suspension of solid particles of a circulating fluidized bed, (ii) a first cyclone separator arrangement receives a mixture of gases and solid particles from the combustion chamber for separating a first fraction of the solid particles from the exhaust gases, and (iii) a solid particle return system connected to the first cyclone separator returns separated solid particles to the combustion chamber, (b) a heat transfer section including a water/steam heat exchanger section arranged after the first cyclone separator arrangement in the exhaust gas flow path, (c) a heat recovery device provided in connection with the combustion chamber, the first cyclone separator arrangement and the heat transfer section being arranged for recovering heat resulting from the combustion process in the combustion chamber, (d) a selective catalytic reduction system arrang

Abstract: A wall construction for a boiler arrangement. The boiler arrangement is formed of at least a furnace and a separator. The furnace has a grid, a bottom part, and an upper part. The separator is arranged by conduits in flow communication with both the upper part and the bottom part of the furnace. The conduits, together with the separator, form an external circulation of bed material. The upper part of the furnace has four vertical walls, and the bottom part of the furnace has a height and four walls extending from the grid up to the vertical walls. The wall construction includes at least one hollow beam being attached to a wall of the bottom part of the furnace and extending substantially over the entire height of the bottom part, and the at least one hollow beam being in flow communication with the external circulation for returning bed material into the furnace.

Abstract: A method of and a plant for combusting carbonaceous fuel, the method including the steps of introducing particulate oxygen selective sorbent, such as a perovskite type material, into an adsorption reactor of the combustion plant to form a first particle bed in the adsorption reactor, fluidizing the first particle bed by an oxygen-containing first fluidizing gas to adsorb oxygen from the fluidizing gas to the sorbent, conveying oxygen-rich sorbent from the adsorption reactor to a combustion reactor of the combustion plant to form a second particle bed in the combustion reactor, fluidizing the second particle bed by an oxygen-deficient second fluidizing gas to desorb oxygen from the sorbent, so as to produce free oxygen gas, and introducing carbonaceous fuel into the combustion reactor to oxidize the fuel with the free oxygen gas.

Abstract: A method of and a power plant for generating power by combusting carbonaceous fuel with substantially pure oxygen, and a method of modifying a process of generating power by combusting carbonaceous fuel from combusting the fuel with air to combusting the fuel with substantially pure oxygen.

Abstract: Means for obtaining accurate knowledge of location and amount of fouling inside a heat exchange system, such as a boiler of a power plant, are provided. According to the invention this knowledge can be used to optimize cleaning of a heat exchange system. The system of the invention comprises: Means for measuring particles in the exhaust gas stream of the heat exchange system. These particles are at least partly released when cleaning a certain part of the heat exchange surface of the heat exchange system. Means for creating information of the fouling in an electronic memory by linking together coordinates of the part of the heat exchange surface being cleaned and the measurement data created during the cleaning of said part.