The present invention provides a circulating fluidized bed boiler, comprising: furnace side walls; a ceiling; an air distribution plate provided at a bottom of a furnace; and at least one air distribution cone provided on the air distribution plate, wherein each air distribution cone extends upwards from the air distribution plate into an interior of the furnace and has a shape gradually tapered in an extending direction, cone side walls which form the air distribution cone are provided with secondary air ports, the cone side walls are separated from the furnace side walls, and a furnace combustion space is formed and surrounded by the ceiling, the furnace side walls, the air distribution plate, and the cone side walls. The present invention further relates to an air distributor for a circulating fluidized bed boiler, the air distributor being provided on an air distribution plate of the boiler, wherein the air distributor is in a form of an air distribution cone, which extends upwards from the air distribution plate into an interior of a furnace to form a shape gradually tapered in an extending direction, and secondary air ports are formed in air distribution cone side walls forming the air distribution cone. The present invention also relates to an air distributor assembly for a circulating fluidized bed boiler.

Disclosed herein are a fluid sand falling type circulating fluidized bed boiler with a plurality of risers for preventing erosion and corrosion of water tubes and increasing combustion efficiency, and a method of operating the same. The fluid sand falling type circulating fluidized bed boiler with a plurality of risers includes a boiler section into which fuel and oxidizer are injected, a riser section connected to the boiler section so that the fuel and fluid sand supplied from the boiler section are introduced from the bottom of the riser section and flow up, and a relay section provided on the boiler section to supply the fluid sand having passed through the riser section to the boiler section, wherein the fuel is injected from the top of the boiler section and burned while flowing down therein.

A ground supported power boiler is described combining a refractory lined and insulated conical floor; an insulated cylindrical combustion chamber; a cylindrical furnace with water tube wall; a rectangular convective section; a single vertical steam drum; tangential injection of the fuel and combustion air; means for fluidizing the fuel bed; means for selectively stripping particulates from the flue gases; multi-stage particulate stripping and filtering from flue gases, means for using the walls of steam drum as steam/water droplet separator, means for recirculating and capturing heat from the flue gases; means for pressurizing the interior of the boiler above atmospheric pressure; means for heating and drying fuel prior to feeding the fuel to the boiler; means for creating hydrogen shift reaction; means for eliminating any need for sootblowing; and designed to not require the use of an induced draft fan.

The purpose of the present invention is to provide a furnace wall in which a throat section with a smaller channel diameter than other regions can be formed using all peripheral wall tubes. Provided is a furnace wall comprising: a plurality of peripheral wall tubes (142), which are disposed so as to form a cylindrical shape when aligned in one direction and through the interior of which cooling water flows; and fins (140) that connect neighboring peripheral wall tubes (142) in an airtight manner. In a throat section in which the diameter of a horizontal cross-section of the cylindrical shape is reduced in comparison to other regions, the peripheral wall tubes (142) are disposed so as to be in mutual contact and the fins (140) are disposed on the inner circumferential sides of the cylindrical shapes.

Disclosed herein are a fluid sand falling type circulating fluidized bed boiler with a plurality of risers for preventing erosion and corrosion of water tubes and increasing combustion efficiency, and a method of operating the same. The fluid sand falling type circulating fluidized bed boiler with a plurality of risers includes a boiler section into which fuel and oxidizer are injected, a riser section connected to the boiler section so that the fuel and fluid sand supplied from the boiler section are introduced from the bottom of the riser section and flow up, and a relay section provided on the boiler section to supply the fluid sand having passed through the riser section to the boiler section, wherein the fuel is injected from the top of the boiler section and burned while flowing down therein.

A particle separator module and a heat exchange chamber module connectable to a circulating fluidized bed boiler. The particle separator module includes 2N vertically aligned steam tubes, N being an integer greater than one. Each of the vertically aligned steam tubes is attached to a boiler upper portion and extends downwards to a predetermined level. Each of the 2N vertically aligned steam tubes is attached to one of N first beams. Each of the N first beams is suspended to hang in a horizontal position at the predetermined level by two adjacent steam tubes of the 2N vertically aligned steam tubes. N second beams are attached in a horizontal position to the top surface of the heat exchange chamber module, which is arranged to be suspended from the particle separator module by having each of the N second beams suspended by two adjacent beams of the N first beams.

A ground supported power boiler is described combining a refractory lined and insulated conical floor; an insulated cylindrical combustion chamber; a cylindrical furnace with water tube wall; a rectangular convective section; a single vertical steam drum; tangential injection of the fuel and combustion air; means for fluidizing the fuel bed; means for selectively stripping particulates from the flue gases; multi-stage particulate stripping and filtering from flue gases, means for using the walls of steam drum as steam/water droplet separator, means for recirculating and capturing heat from the flue gases; means for pressurizing the interior of the boiler above atmospheric pressure; means for heating and drying fuel prior to feeding the fuel to the boiler; means for creating hydrogen shift reaction; means for eliminating any need for sootblowing; and designed to not require the use of an induced draft fan.

The purpose of the present invention is to provide a furnace wall in which a throat section with a smaller channel diameter than other regions can be formed using all peripheral wall tubes. Provided is a furnace wall comprising: a plurality of peripheral wall tubes (142), which are disposed so as to form a cylindrical shape when aligned in one direction and through the interior of which cooling water flows; and fins (140) that connect neighboring peripheral wall tubes (142) in an airtight manner. In a throat section in which the diameter of a horizontal cross-section of the cylindrical shape is reduced in comparison to other regions, the peripheral wall tubes (142) are disposed so as to be in mutual contact and the fins (140) are disposed on the inner circumferential sides of the cylindrical shapes.

A watertube panel portion for a fluidized bed reactor and a corresponding method. The watertube panel portion includes multiple parallel metal tubes having a tube length L1, an outer surface, an original outer diameter OD1, and an original wall thickness WT1, and a circumferentially extending recess formed in a central portion of each of the tubes, between first and second end portions. The recess has a constant depth D that is less than the wall thickness WT1. The recess encircles the outer surface of the central portion of the metal tube. A circumferentially extending metal coating has a constant thickness of at most the depth D of the recess to blanket the recess of each of the multiple metal tubes. A fin is continuously welded between each pair of adjacent tubes.

A ground supported power boiler is described combining a refractory lined and insulated conical floor; an insulated cylindrical combustion chamber; a cylindrical furnace with water tube wall; a rectangular convective section; a single vertical steam drum; tangential injection of the fuel and combustion air; means for fluidizing the fuel bed; means for selectively stripping particulates from the flue gases; multi-stage particulate stripping and filtering from flue gases, means for using the walls of steam drum as steam/water droplet separator, means for recirculating and capturing heat from the flue gases; means for pressurizing the interior of the boiler above atmospheric pressure; means for heating and drying fuel prior to feeding the fuel to the boiler; means for creating hydrogen shift reaction; means for eliminating any need for sootblowing; and designed to not require the use of an induced draft fan.