| FOSTER WHEELER NORTH AMERICA CORP. Patent applications |
| Patent application number | Title | Published |
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| 20120129112 | Method Of And A System For Combusting Fuel In An Oxyfuel Combustion Boiler - 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. | 05-24-2012 |
| 20110294077 | Method of Controlling a Boiler Plant During Switchover From Air-Combustion to Oxygen-Combustion - 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. The method makes it possible to reduce CO | 12-01-2011 |
| 20110265697 | Circulating Fluidized Bed Combustor and a Method of Operating a Circulating Fluidized Bed Combustor - 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 arranged in the exhaust gas flow path, after the heat transfer section, for removing NOx from the exhaust gas, (e) a device for injecting NOx reducing agent into the exhaust gases upstream of the selective catalytic reduction system, and (f) a second cyclone separator arrangement provided downstream of the first cyclone separator arrangement and upstream of the heat transfer section, in which a second fraction of the solid particles is separated form the exhaust gases. | 11-03-2011 |
| 20110226195 | Wall Construction for a Boiler Arrangement - 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. | 09-22-2011 |
