Abstract: A method of reducing sulfur dioxide emissions of a circulating fluidized bed boiler includes the steps of (a) feeding a first stream comprising a sulfur-containing carbonaceous fuel to a furnace of the boiler; (b) feeding a second stream comprising calcium carbonate to the furnace at a rate relative to the first stream such that the molar ratio of calcium in the second stream to sulfur in the first stream (the Ca/S molar ratio) is between about 1.2 and about 0.

Abstract: A method and an apparatus in a fluidized bed heat exchanger including a heat exchange chamber having a fluidized bed of solid particles, heat transfer surfaces, an inlet, and an outlet. Particles are fed through the inlet onto the upper surface of the bed of solid particles by a guiding channel. The guiding channel, which extends from above the upper surface of the bed of solid particles to the surface thereof, or to below the surface, passes the solid particles to the restricted area of the surface. The outlet is formed in the area of the guiding channel to remove particles from the area delimited by the guiding channel. Uncooled particles can thus be removed from the heat exchange chamber.

Abstract: A centrifugal separator assembly, which is attached to a fluidized bed reactor for separating solid particles from gas exhausted from a reaction chamber of the fluidized bed reactor, includes a vortex chamber. The vortex chamber is in a horizontal direction defined by vertically-extending outer walls formed of planar water tube panels, the inside of the outer walls being at least partly provided with a refractory lining and defining a gas space in the vortex chamber, where at least one vertical gas vortex is established. The separator assembly also includes at least one inlet for introducing gas into the gas space from the reaction chamber, at least one outlet for discharging purified gas from the gas space, and at least one outlet for discharging separated solid particles from the gas space.

Abstract: A power generating system having a hybrid gasification cycle, in which CO2 is recycled to a gasifier to be used as a gasification reactant and working fluid. The power generating system includes a source of fresh, pure oxygen, a gasifier, a particle separator arranged in flow connection with the gasifier, a syngas combustor, a gas turbine arranged in flow connection with the syngas combustor, a steam generator arranged in flow connection with the outlet of the gas turbine, and a gas compressor system which discharges a stream of compressed exhaust gas. A first portion of the stream of compressed exhaust gas is conducted to the gasifier to control the temperature in the gasifier, to provide CO2 and steam for gasification, and to decrease the demand for fresh, pure oxygen therein.

Abstract: A fluidized bed reactor includes at least one furnace section delimited by side walls and a bottom grid, the at least one furnace section provided for containing a bed of fluidized solid particles therein, and a supply for introducing a gas into the at least one furnace section at a level above the bottom grid. The supply includes (i) a gas source chamber, (ii) at least one opening in at least one of the side walls at a level above the bottom grid, and (iii) at least one conduit, having a first end connected to the at least one opening at a first vertical level and a second end connected to the gas source chamber for introducing gas from the gas source chamber to the at least one furnace section. The at least one conduit provides a solid flow preventing element for preventing solid particles from flowing backward from the at least one furnace section into the at least one conduit.

Abstract: A grid construction for a fluidized bed reactor, the reactor including a reaction chamber defined by substantially vertical walls, in which a fluidized bed of solid particles is maintained, and a windbox under the reaction chamber, in a lower portion of the reactor. The grid construction is positioned between the reaction chamber and the windbox and includes (a) multiple continuous nozzle lines for distributing fluidizing gas from the windbox into the reaction chamber, for suspending the fluidized bed in the reaction chamber, and (b) continuous trenches between the nozzle lines. The nozzle lines include multiple gas outlets, having a main gas flow direction, at side faces of said nozzle lines, for directing fluidizing gas jets towards an adjacent trench.

Abstract: A circulating fluidized bed reactor includes a furnace, defined by a substantially vertical and planar first wall, and a particle separator having a return duct adjacent to the first wall. In the lower part of the return duct is arranged a gas seal adjacent to a planar tube wall, which wall is the planar wall or a wall defining a space in gas flow connection with the furnace. The width of the horizontal cross section of the lower part of the return duct, measured in the direction of the first wall, is larger than its depth, measured perpendicular to the width. The gas seal includes a seal structure that includes water tubes bent from the tube wall.

Abstract: A fluidized bed reactor includes a furnace defined by side walls, a roof, and a continuous bottom, and has a solid particle bed in the furnace. Vaporizing surfaces form at least two principally vertical chambers. The chambers have a round or polygonal cross section, and extend from the bottom upwards to at least 80% of the height of the furnace. Also, the chambers are spaced away from the side walls of the furnace and are arranged separately within the furnace, for the furnace volume to be free so that the particles move even in the proximity of the chambers.

Abstract: A process for recovering metal material from waste material including organic material and metal material in the form of thin foil metal material.

Abstract: A method of and apparatus for controlling heat transfer in a fluidized bed reactor having a heat transfer chamber (312) with a bed (314) of solid particles therein, means (320,322) for introducing fluidizing gas into the heat transfer chamber for fluidizing the bed of solid particles therein and heat transfer surfaces (316) in contact with the bed of solid particles in the heat transfer chamber. Heat is transferred to said heat transfer surfaces from the solid particles. The fluidization of the bed of solid particles is varied according to a periodical function, e.g. by control means (34) periodically varying the flow velocity of fluidizing gas being introduced into the heat transfer chamber. Thereby the instantaneous heat transfer, as well as, the effective heat transfer from solid particles to the heat transfer surfaces may be controlled.

Abstract: A method and an apparatus for reducing NOx emissions in CFB reactors used for combusting fuel at atmospheric pressure. The CFB reactor includes a combustion chamber having a fluidized bed of particles therein, a particle separator section including one or more consecutive particle separators, a convection section and a clean gas duct connecting the particle separator to the convection section. The apparatus also includes a device for injecting ammonia or its precursor into the flue gases, for reducing NOx therein. The ammonia or its precursor is injected into the clean gas duct connecting the last separator to the convection section, the clean gas duct having a very small density of solid particles herein. The temperature in the clean gas duct is sufficient for NOx reducing reactions.

Abstract: An apparatus that includes (i) a centrifugal separator assembly and (ii) a fluidized bed reactor having a reactor chamber, the separator assembly being connected to the reactor and provided for separating solid particles from gas discharged from the reactor chamber. The apparatus includes planar peripheral walls defining a vortex chamber, having a rectangular cross section, the vortex chamber having an interior gas volume in which at least two vertical gas vortices can be formed, and the planar peripheral walls including a first wall portion connecting the separator assembly to the reactor chamber, at least two gas outlets, disposed one after the other in the longitudinal direction of the vortex chamber, for discharging cleaned gas from the gas volume, at least one solid particles outlet for discharging separated solid particles from the gas volume, and at least one gas inlet, arranged in the first wall portion, for introducing gas from the reactor chamber into the gas volume.

Abstract: A method of and apparatus for decreasing attack of detrimental components of solid particle suspensions on heat transfer surfaces in a heat transfer chamber in a fluidized bed reactor. The method includes introducing solid particles into a first chamber, which is a dilution chamber, on top of a bed of solid particles therein through a dilution chamber inlet disposed in an upper part of the dilution chamber, and discharging solid particles from the dilution chamber through an outlet disposed in a lower part of the dilution chamber, into a heat transfer chamber, and introducing a flushing gas into at least a portion of the dilution chamber for performing at least one of inactivating in and separating from the bed of solid particles in the dilution chamber, impurities detrimental to heat transfer surfaces in the heat transfer chamber.

Abstract: A grate construction for a fluidized bed boiler, the boiler including a furnace defined by substantially vertical walls in which a fluidized bed of solid particles is maintained, a windbox under the furnace in the lower part of the boiler, a grate construction being positioned between the furnace and the windbox and forming an upper surface of the windbox, for suspending the fluidized bed in the furnace and an outlet duct for withdrawing from the boiler solid material removed from the grate. The grate construction includes a device for distributing fluidizing air or other equivalent gas from the windbox into the furnace and a device for removing coarse solids from the grate construction.

Abstract: A method of operating a fluidized bed reactor system for reacting fuel. The method includes introducing solid material particles, fluidization medium and fuel into a reactor chamber to provide a fluidized bed therewithin, reacting the fuel material within the fluidized bed to produce exhaust gas and discharging the exhaust gas from a reactor chamber outlet, introducing the exhaust gas into a particle separator and separating solid particles from the gas in the particle separator, discharging from the particle separator gas through a gas outlet and a first flow of separated solid particles through a solid particle outlet, and cooling, in a gas cooler, the gas discharged from the separator. A second flow of solid particles is branched off from the first flow of solid particles, before or after discharging the first flow of solid particles from the particle separator.

Abstract: Method and apparatus for gasifying of a solid carbonaceous material in a fluidized bed reactor in which the solid particles entrained by the gases being removed from the upper part of the reactor are separated and returned to the lower part of the reactor. oxygenous gas is supplied into the lower part of the reactor and the non-reacted carbonaceous material separated from the gases is oxidized in the lower part of the reactor. The carbonaceous material is introduced above the oxidizing zone into a zone substantially free of oxygen and the carbonaceous material is pyrolyzed and reduced by means of the hot gases and particles rising from the lower part of the reactor.

Abstract: A pressurized fluidized bed combustion system includes a pressure vessel, a furnace section within the pressure vessel for forming high temperature, high pressure gases and for generating steam, a compressor for providing compressed combustion air for the furnace section, a filter for cleaning the high temperature, high pressure flue gases formed in the furnace section, a gas turbine for generating power from the gases formed in the furnace section and cleaned in the filter, a steam turbine cycle for generating power from the steam generated in the furnace section, a heat recovery section, connected to the steam turbine cycle, for recovering heat from the gases exhausted from the gas turbine and for supplying the heat to feedwater provided for the steam generation in the furnace section, and an inlet duct for the filter. The inlet duct is connected between a gas discharge channel in the furnace section and a gas inlet channel in the filter.

Abstract: A fluidized bed reactor including in its lower part a furnace section having a bed of fluidized solid particles, the furnace section being delimited by side walls such as external side walls and/or partition walls and a bottom grid, and a supplying device for introducing gas into the furnace section at a level above the bottom grid, the supplying device including a gas source chamber, an opening in at least one of the side walls at a level above the bottom grid, and a conduit having a first end connected to the opening and a second end connected to the gas source chamber. The conduit includes a solid flow seal preventing solid particles from flowing backwards from the furnace section into the conduit in a manner preventing or noticeably decreasing introduction of gas from the gas source chamber to the furnace section.

Abstract: An apparatus for reducing the concentration of nitrogen oxides in flue gases produced in a furnace of a combustion unit includes a device for maintaining combustion reactions in the furnace, the combustion reactions resulting in the production of hot gases containing nitrogen oxides, the hot gases flowing mainly upwardly within the furnace, internal heat transfer surfaces within the furnace for recovering heat from the mainly upward flow of hot gases, an introducer for introducing nitrogen oxides reducing agent into the upward flow of hot gases in the furnace, for reducing the concentration of nitrogen oxides in the hot gases, wherein the introducer is integrally connected to the internal heat transfer surfaces, for keeping the temperature of the reducing agent at a sufficiently low temperature level upon introduction thereof into the furnace, and for efficiently mixing the reducing agent with the upward flow of hot gases, and a discharge for discharging flue gases from the furnace.

Abstract: A power generation method includes steps of fluidizing a bed of combustible material in a furnace section to combust the combustible material, discharging a flow of high temperature flue gases and fine particulate material entrained therein from the furnace section, introducing the flow of high temperature flue gases and the fine particulate material into a flue gas temperature controller, dividing the flow of high temperature flue gases and the fine particulate material into first and second flows of flue gases in the flue gas temperature controller, decreasing the temperature of the second flow of flue gases in the temperature controller, to provide a cooled flow of flue gases, combining the first flow of flue gases and the cooled flow of flue gases in the temperature controller to provide a recombined flow of flue gases, introducing the recombined flow of flue gases and the fine particulate material entrained therein into a high temperature ceramic filter, measuring the temperature of the hot flue gases an