A circulating fluidized bed (CFB) boiler has one or more bubbling fluidized bed enclosures containing heating surfaces and located within a lower portion of the CFB boiler to provide an in-bed heat exchanger (IBHX). Solids in the bubbling fluidized bed are maintained in a slow bubbling fluidized bed state by separately controlled fluidization gas supplies. The beds feature open bottom distribution grids with hoppers disposed below to collect solids. The enclosure defining the IBHX is supported from structures below the grids and the enclosure can be supported from the hoppers.

A circulating fluidized bed (CFB) boiler has one or more bubbling fluidized bed enclosures containing heating surfaces and located within a lower portion of the CFB boiler to provide an in-bed heat exchanger (IBHX). Solids in the bubbling fluidized bed are maintained in a slow bubbling fluidized bed state by separately controlled fluidization gas supplies. The beds feature open bottom distribution grids with hoppers disposed below to collect solids. The enclosure defining the IBHX is supported from structures below the grids and the enclosure can be supported from the hoppers.

Methods, devices and systems for processing of solid materials, particularly fuel material solids such as carbonaceous fuel solids such as of granular form, to provide or result in an even distribution of the solid material. Hoppers are provided with plurality of outlet orifices, each of the outlet orifices adapted to flow therethrough a combination of gas and the solid material to pneumatically convey the solid material to a distribution manifold. The distribution manifold includes a plurality of tubes with each tube having a plurality of exit orifices wherein each exit orifice passes an equal portion of the combination of the gas and the solid material.

A device with annular spouted fluidized bed can be used for carrying out the majority of the technical processes carried out in fluidized bed devices. The reaction chamber of the device has, throughout at least a part of its height, a downwardly tapering funnel shape with step-structured inner surface. The shape of the reaction chamber, together with the tangential admission thereto of fluidized and other gases, makes it possible to create, in the reaction chamber, an adjustable toroidal fluidized bed, in which the rotation rate of the particles of the material undergoing treatment can be adjusted in both horizontal and vertical planes, and also makes it possible to control the dwell time of particles of different sizes in the reaction zone, the intensity with which materials are treated, and other process parameters.

A device with annular spouted fluidized bed can be used for carrying out the majority of the technical processes carried out in fluidized bed devices. The reaction chamber of the device has, throughout at least a part of its height, a downwardly tapering funnel shape with step-structured inner surface. The shape of the reaction chamber, together with the tangential admission thereto of fluidized and other gases, makes it possible to create, in the reaction chamber, an adjustable toroidal fluidized bed, in which the rotation rate of the particles of the material undergoing treatment can be adjusted in both horizontal and vertical planes, and also makes it possible to control the dwell time of particles of different sizes in the reaction zone, the intensity with which materials are treated, and other process parameters.

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.

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.

Disclosed is a system and method for the combustion of biomass material employing a swirling fluidized bed combustion (SFBC) chamber, and preferably a second stage combustion carried out in a cyclone separator. In the combustion chamber, primary air is introduced from a bottom air box that fluidizes the bed material and fuel, and staged secondary air is introduced in the tangential direction and at varied vertical positions in the combustion chamber so as to cause the materials in the combustion chamber (i.e., the mixture of air and particles) to swirl. The secondary air injection can have a significant effect on the air-fuel particle flow in the combustion chamber, and more particularly strengthens the swirling flow, promotes axial recirculation, increases particle mass fluxes in the combustion chamber, and retains more fuel particles in the combustion chamber. This process increases the residence time of the particle flow. The turbulent flow of the fuel particles and air is well mixed and mostly burned in the combustion chamber, with any unburned waste and particles being directed to the cyclone separator, where such unburned waste and particles are burned completely, and flying ash is divided and collected in a container connected to the cyclone separator, while dioxin production is significantly minimized if not altogether eliminated. A Stirling engine along with cooling system and engine control box is integrated with the SFBC chamber to produce electricity from the waste combustion process. Residual heat in the flue gas may be captured after the combustion chamber and directed to a fuel feeder to first dry the biomass. System exhaust is directed to a twisted tube-based shell and tube heat exchanger (STHE) and may produce hot water for space heating.

Disclosed is a system and method for the combustion of biomass material employing a swirling fluidized bed combustion (SFBC) chamber, and preferably a second stage combustion carried out in a cyclone separator. In the combustion chamber, primary air is introduced from a bottom air box that fluidizes the bed material and fuel, and staged secondary air is introduced in the tangential direction and at varied vertical positions in the combustion chamber so as to cause the materials in the combustion chamber (i.e., the mixture of air and particles) to swirl. The secondary air injection can have a significant effect on the air-fuel particle flow in the combustion chamber, and more particularly strengthens the swirling flow, promotes axial recirculation, increases particle mass fluxes in the combustion chamber, and retains more fuel particles in the combustion chamber. This process increases the residence time of the particle flow. The turbulent flow of the fuel particles and air is well mixed and mostly burned in the combustion chamber, with any unburned waste and particles being directed to the cyclone separator, where such unburned waste and particles are burned completely, and flying ash is divided and collected in a container connected to the cyclone separator, while dioxin production is significantly minimized if not altogether eliminated. A Stirling engine along with cooling system and engine control box is integrated with the SFBC chamber to produce electricity from the waste combustion process. Residual heat in the flue gas may be captured after the combustion chamber and directed to a fuel feeder to first dry the biomass. System exhaust is directed to a twisted tube-based shell and tube heat exchanger (STHE) and may produce hot water for space heating.

The invention is in the technical field of bubbling fluidized bed combustion and relates to the use of ilmenite particles with an average particle size <dp> between 0.1 mm and 1.8 mm as bed material for a bubbling fluidized bed (BFB) boiler with an excess air ratio () below 1.3 and to a method for operating a bubbling fluidized bed (BFB) boiler, comprising carrying out the combustion process with a bubbling fluidized bed comprising ilmenite particles as defined in any one of claims 1 and 4-5; and setting the excess air ratio () to a value below 1.3.